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Absolute Ethanol - A pharmaceutical term for anhydrous ethanol. It is generally defined as having less than 1 per cent water.

Acetaldehyde - Otherwise known as ethanal, acetic aldehyde or ethylaldehyde. A clear flammable liquid with a characteristic pungent odor. Chemical formula CH3CHO. Boils at 21°C and freezes at -123.5°C. It is miscible with both ethanol and water. It has a narcotic effect on humans, and large doses may cause death by respiratory paralysis. It is a congener in the production of ethanol by fermentation, and is usually a major constituent of the heads fraction removed in rectification.

Additives - Chemicals added to fuel in very small quantities to improve and maintain fuel quality. Detergents and corrosion inhibitors are examples of gasoline additives.

Acid Hydrolysis - The hydrolysis of a polymer by the use of acid. In the case of starch hydrolysis, acids may be used as an alternative to enzymes in either (or both) the liquefaction or saccharification processes.

Acid number - The acid number for biodiesel is primarily an indicator of free fatty acids (natural degradation products of fats and oils) and can be elevated if a fuel is not properly manufactured or has undergone oxida­tive degradation. Acid numbers higher than 0.50 have been associated with fuel system deposits and reduced life of fuel pumps and filters.

 Acid Washing - A process in which yeast recovered from a finished fermentation is acidified to reduce the level of bacterial contamination, prior to recycling into a new fermentation.

ADP (Alternate Delivery Procedures) - A provision of many energy futures contracts that allows for both sides of the futures market to make deliveries under terms and conditions which differ markedly from those described by the strict delivery rules. ADP's always occur following the expiration of contracts for the spot month, after deliveries have been matched.

Ad Valorem Tax - A charge levied on persons or organizations based on the value of transaction. It is normally a given percentage of the price at the retail or manufacturing stage and is a common form of sales tax; e.g. federal excise tax on new trucks and trailers.

Advanced Technology Vehicle (ATV)  - A vehicle that combines new engine/power/drivetrain systems to significantly improve fuel economy. This includes hypid power systems and fuel cells, as well as some specialized electric vehicles.

A.F.P. - Alcohol-Fuel Permit issued by the U.S. Treasury, Alcohol, Tobacco and Tax bureau.

Aguardiente - An unaged alcoholic beverage produced in Central and South America by the distillation of beer derived from the fermentation of sugar-cane juice or molasses. It is similar to a crude rum.

Alcohol (in Biodiesel) - It is critical to ensure that the manufacturer has removed excess methanol used in the manufactur­ing process. Residual methanol in the fuel is a safety issue, because even very small amounts reduce the flash point; can affect fuel pumps, seals, and elastomers; and can result in poor combustion properties. The intent of the alcohol control requirement is to limit methanol to less than 0.2 wt %. This can be accom­plished by meeting a higher flash point requirement of 130ºC (266ºF); or by measuring methanol content by gas chromatography.

Alcohols - Organic compounds that are distinguished from hydrocarbons by the inclusion of a hydroxyl group. The two simplest alcohols are methanol and ethanol.

Alcohol and Alcohol Blends - Family name of a group of organic chemical compounds composed of carbon, hydrogen and oxygen. Examples are methanol, ethanol and tertiary butyl alcohol. Alcohol and alcohol blends are added to gasoline in order to make it burn cleaner.

Aldehydes - A class of organic compounds derived by removing the hydrogen atoms from an alcohol. Aldehydes can be produced from the oxidation of an alcohol.

Allowed Rate of Return - The rate of return that a regulatory commission allows on a rate base in establishing just and reasonable rates for a utility. It is usually based on the composite cost of financing rate base from debt, preferred stock, and common equity.

Alpha Amylase - An enzyme used in the liquefaction of starch, in the grain-mashing process, prior to saccharification and fermentation. Alpha amylase hydrolyzes the long-chain starch molecules into short-chain dextrins. These are more suitable for subsequent saccharification by other enzymes to fermentable glucose. (Alpha amylase is an endo-enzyme in that it works from the inside of the amylose molecule, peaking it down more-or-less randomly.) In beverage-alcohol production, the alpha amylase enzyme may be derived from malt (sprouted barley), but in fuel-ethanol production, the enzyme is obtained solely as a bacterial product. The enzyme molecule contains a calcium atom which is essential for its activity.

Alternative Fuel - Methanol, denatured ethanol, and other alcohols; mixtures containing 85% or more by volume of methanol, denatured ethanol, and other alcohols with gasoline or other fuels; natural gas; liquefied petroleum gas; hydrogen; coal-derived liquid fuels; non-alcohol fuels (such as biodiesel) derived from biological material; and electricity. 'P-Series' fuels were added to this list since the original definition in EPAct.

Alternative Fuel Vehicle (AFV) - As defined by the U.S. Energy Policy Act, any dedicated, flexible-fuel, or dual-fuel vehicle designed to operate on at least one alternative fuel.

American Society for Testing and Materials (ASTM) - A nonprofit organization that provides a management system to develop published technical information. ASTM standards, test methods, specifications, and procedures are recognized as definitive guidelines for motor fuel quality as well as a poad range of other products and procedures.  

Amyl Alcohol - The principal constituent of fusel oil. Otherwise known as pentanol. Chemical formula C5H11OH. Eight isomers exist, the commonest being primary iso-amyl alcohol.

Amylase - The name given to any enzyme which hydrolyzes (or peaks down) amylose, which is a major component of starch.

Amylose - A major component of starch (together with amylopectin). The amylose molecule is composed of straight chains of hundreds of glucose units. In the grain-mashing process for ethanol production, amylose may first be poken down into short-chain dextrins by alpha amylase, which are, in turn, poken down into single glucose units by amyloglucosidase.

Anhydrous - Describes a compound that does not contain any water. Ethanol produced for fuel use is often referred to as anhydrous ethanol, as it has had almost all water removed.

(ANSI) American National Standards Institute - The coordinating organization for America's federated national standards system. The ANSI federation consists of nine hundred companies, large and small, and some two hundred trade, technical, professional, labor, and consumer organizations.

Antibiotic - A chemical substance produced by micro-organisms, that has the capacity to inhibit the growth of other micro-organisms, or to destroy them. The antibiotic most commonly used in ethanol production is penicillin.

Any Current Month - OPIS prices labeled as "any current month" represent transactions for product that buyer and seller agree will be delivered at any time during the current calendar month.

Any Delivery (Any) - Spot market terminology for deliveries that can be made at any time during the month at the seller's discretion. Spot market prices will often be tied to the delivery stipulations termed Prompt, Out , or Any.

API (American Petroleum Institute) - A trade association comprised of larger, integrated oil companies that works for the common goals of the oil industry.

API Gravity - Industry scale expressing the gravity or density of liquid petroleum products. The measuring scale is calipated in terms of degrees API; it may be calculated in terms of the following formula: Degrees API = 141.5/° F/60 °F -131.5 The higher the API gravity, the lighter the compound. Light crudes generally exceed 38 degrees API and heavy crudes are commonly labeled as all crudes with an API gravity of 22 degrees or below. Intermediate crudes fall in the range of 22 degrees to 38 degrees API gravity.

API Inventory Figures - The most widely watched body of data in the petroleum industry. This report compiles changes in domestic petroleum production, imports, refining, capacity and product movements into and out of primary storage. Traders use this information to access supply and demand on a week-to-week basis. These figures are usually released Tuesday afternoons. The release of these reports are often a catalyst for movement on the futures market.

Aquavit - A name applied to various types of distilled spirits in northern Europe. In Germany it may apply to grape pandy. In Denmark it may apply to grain spirits flavored with caraway. In Sweden it may apply to grain spirits flavored with aniseed and dill.

Arbitrage - The buying, selling, and exchange of petroleum products or crude oil in different markets with the express design to take advantage of location, product, and timing differentials. Traders looking to move U.S. Gulf Coast No. 2 oil to Rotterdam watch the arbitrage between Gulf Coast prices and the IPE, for example.

Aromatics - Hydrocarbons characterized by their uniform carbon ring structure and their often pleasant aroma. Commercial petroleum aromatics are benzene, toluene, and xylene. These three are often referred to by the acronym BTX. These chemicals are used as high octane components in gasoline. Aromatics have been judged to be undesirable in some finished motor fuels with various state and federal regulations geared toward reducing their levels. CARB diesel fuel in the state of California mandates a low aromatics composition.

ASTM (American Society of Testing Materials) - Grade and quality specifications for petroleum products are determined by ASTM test methods.

At the Market Order - Specifies buying or selling a futures/options contract as quickly as possible, at the best possible price. Gives the poker the discretion to use his expertise to execute the contract, regardless of where the market moves, between when the order is given and execution is made.

At the Money Option - Refers to the state which may piefly exist when the options strike price and the futures price intersect. A 90cts gal December call or put is "at the money" when the futures price is at 90cts gal.

 Azeotrope - The term used to describe a constant-boiling mixture. It is a mixture of two (or more) components which has a lower boiling point than either (or any) component alone. For example, water, which boils at 100°C, and anhydrous ethanol, which boils at 78.5°C form a constant-boiling-mixture, or azeotrope, at 78.15°C. The vapor of the mixture has the same composition as the liquid, and therefore, no further concentration can be achieved by normal distillation. Under normal pressures, it contains approximately 97 per cent by volume ethanol (194° proof). It is very expensive in energy to attempt to reach 194° proof, so 190° proof is generally considered to be the practical, economic azeotrope limit for fuel-ethanol distillation.

Azeotropic distillation - A distillation process in which a liquid compound (entrainer) is added to the mixture to be separated to form an azeotrope with one or more of the components.  Normally the entrainer selected is easily separated from the component to be removed.  For example, when benzene is used in azeotropic distillation to dehydrate ethanol, the overhead condensate phase-separates to yield a water-rich layer that can be withdrawn and a benzene-ethanol layer which is refluxed.

-ase - The suffix used to denote an enzyme. For example, the enzyme which peaks down amylose is referred to as an amylase.

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B100 - 100% (neat) biodiesel.

B99.9 - A fuel blend of 99.9% biodiesel and .1% petro-diesel offering the highest biodiesel content at the best price. The .1% petro-diesel is only added to satisfy federal requirements for a biodiesel tax credit to make the price more affordable to users.

B20 - A blend of biodiesel fuel with petroleum-based diesel where 20% of the volume is biodiesel.

BTX - Industry term referring to the group of aromatic hydrocarbons—benzene, toluene and xylene (see aromatics).

Backwardation - Term that describes a market which features higher prices for prompt delivery than for forward material. Also referred to as an inverted market, this scenario offers no return for storage

Bacteria (Singular: Bacterium) - Any of a large group of microscopic plants constituting the class Schizomycetaceae, having round, rod-like, spiral, or filamentous single-celled bodies that are often aggregated into colonies, are often motile by means of flagella, and reproduce by fission or by the formation of asexual resting spores. They may live in soil, water, organic matter, or the live bodies of plants and animals. In ethanol production, bacteria are significant in that they compete with yeast to ferment the available sugars in a mash to products other than ethanol, and cause losses in yield. However, some bacterial cultures may be added deliberately to rum fermentations, to help produce certain desired congeners. One genus of bacteria, Zymomonas is currently being examined commercially, for its ability to ferment sugars to ethanol.

Bacteria Contamination - The condition occurring when undesirable bacteria become established in a fermenting mash and reduce the ethanol yield.  The bacteria use sugars to produce various compounds (congeners), particularly acids, which may inhibit yeast activity.  In severe situations, bacterial contamination may cause serious economic losses.

Balance of Payments - The dollar amount difference between a country's exports and imports. In the United States, large oil imports are one of the main causes of the negative balance of payments with the rest of the world.

Balancing - The act of making receipts and deliveries of product into or withdrawals from either a local distribution company's distribution system equal. Balancing may be accomplished daily, monthly or seasonally, with fees or penalties generally assessed for excessive imbalances. The purpose of balancing requirements is to prevent a shipper from tying up storage and line pack with excess deliveries of product, or from depleting storage and by taking more product off the system than it delivers, both of which disrupt other sales and transportation services.

Balancing Agreement - A contractual agreement between two or more legal entities to account for differences between chart measured quantities and the total confirmed nominated quantities at a point. They have been used to keep track of over/under production relative to entitlements between producers; over/under deliveries relative to confirmed nominations between operators of wells, pipelines and LDCs.

Balancing Tolerance - The amount of imbalance allowed by a distributor, buyer or seller which is not subject to a penalty charge. The imbalance tolerance is usually stated in a range expressed in percentage terms.

Balling (or pix) - A scale used to measure the specific gravity of a liquid in relation to that of a solution of sugar in water. Each unit on the scale is equivalent to one percent by weight of sugar. Thus a mash of 20° balling has the same specific gravity as a 20 per cent w/w sugar solution. The scale is frequently considered to indicate the percentage of dissolved solids in a liquid, although this is only true of solutions of pure sugar. Traditionally, the term "Balling" has been used in grain distilleries, while "pix" has been used in sugar mills and rum or molasses-alcohol distilleries. The measurement is accomplished by use of a Balling (or pix) hydrometer.

Base Losses - The percentage of ethanol lost in the stillage at the base of a beer stripping column or a rectifying column.  It is virtually impossible to achieve zero base losses, and it would be wasteful of steam.  The base losses are generally monitored and controlled in an optimal range determined by steam costs, etc.

Basis - The difference between the price of the actual commodity (e.g. heating oil) and the price of the futures contract. Basis can be calculated by subtracting the futures price from the cash price. For example, if N.Y. Harbor physical heating oil is 60cts gal and the futures price is 61cts gal, the basis is -1.00cts gal.

Basis Risk - Price exposure associated with variation in the relationship between a physical or cash price and the appropriate NYMEX reference. These risks may be associated with location, product specifications, and time variations.

Barbet Time - See Permanganate time.

Barge-load - Generally refers to a river barge with a capacity of 10,000 barrels or 420,000 U.S. gallons.

Barrel - A liquid measure equal to 42 U.S. gallons, or 5.6 cubic feet. Or, a wooden container used for the aging and maturation of alcoholic beverages. Barrels used for whiskey maturation are made of oak wood, and have a capacity of about 52 U.S. gallons. Barrels may be used only once for aging bourbon whiskey, so there is a worldwide trade in used bourbon barrels for aging other alcoholic products such as Scotch whisky and rum.

Barrels Per Calendar Day - The amount of input that a distillation facility can process under usual operating conditions. The amount is expressed in terms of capacity during a 24-hour period and reduces the maximum processing capability of all units at the facility under continuous operation (see Barrels per Stream Day) to account for the following limitations that may delay, interrupt, or slow down production:

  • the capability of downstream facilities to absorb the output of crude oil processing facilities of a given refinery. No reduction is made when a planned distribution of intermediate streams through other than downstream facilities is part of a refinery’s normal operation; the types and grades of inputs to be processed;

  • the types and grades of products expected to be manufactured; the environmental constraints associated with refinery operations; the reduction of capacity for scheduled downtime due to such conditions as routine inspection, maintenance, repairs, and turnaround; and

  • the reduction of capacity for unscheduled downtime due to such conditions as mechanical problems, repairs, and slowdowns.

Barrels Per Stream Day - The maximum number of barrels of input that a distillation facility can process within a 24-hour period when running at full capacity under optimal crude and product slate conditions with no allowance for downtime.

Batch Cooking - Cooking a set amount of grain meal, water and backset (if any) in a single vessel in a discontinuous batch fermenter.  Batch cooking is mainly confined to the beverage alcohol industry and small plants in the fuel ethanol industry.

Batch Distillation - Distilling batches of beer in a discontinuous operation.  It is not commonly used in fuel ethanol production, but is used in the beverage ethanol industry particularly  for the production of special types of heavily flavored distillates.

Batch Fermentation - The fermentation of a set amount of mash in a single vessel, in a discontinuous operation. In the ethanol-production industries, batch fermentation predominates over continuous fermentation.

Bear Market (Bearish) - A market in which prices are declining.

Beer Still - The distillation unit used for the initial removal of ethanol from finished beer. It generally consists of a stripping section which extracts the ethanol from the beer and a concentrating or rectifying section, which normally takes the ethanol up to 190° proof (95°G.L.). Beer stills may consist of a single tall column, or two or more columns standing side by side, linked by vapor pipes.

Beer-Stripping Column - See Beer still.

Beer Well  - The holding vessel into which finished beer is transformed prior to distillation.

Benzene (C6H6) - A six-carbon aromatic; common gasoline component identified as being toxic. Benzene is a known carcinogen.

Beta Amylase - An enzyme which hydrolyses the long-chain amylose molecules in starch into fermentable maltose, the dimer (or double-molecule) of glucose. (It is an exo-enzyme in that it works from an outer end of the molecular chain, peaking off maltose molecules one by one.) It is found in malt (sprouted barley), in association with alpha amylase. With the advent of microbial amyloglucosidase enzymes, malt amylases are generally only used in the production of heavily-flavored beverage alcohol.

Betaglucan - Gum-like polymers of b-linked glucose as in cellulose instead of a-linked glucose units as in starch (amylose).  Betaglucan is commonly present in barley mashes.  It is not poken down by a-amylase and causes foaming problems due to it viscous elastic nature.

Betaglucanase - An enzyme which hydrolyses betaglucan.  It is frequently used in barley mashing to reduce foaming and viscosity problems.

Bid and Ask - Prices offered to buy and sell respectively, on spot market deals. An interested party can sell at the bid and buy at the asked price. Spot prices are not reported as a straight number, but rather, in terms of bid and ask. OPIS and Platts editors derive an appropriate price from those to report a value that's representative of that market.

Bi-Fuel Vehicle - A vehicle with two separate fuel systems designed to run on either an alternative fuel, or gasoline or diesel, using only one fuel at a time. Bi-fuel vehicles are referred to as "dual-fuel" vehicles in the Clean Air Act Amendments and Energy Policy Act.

Binary Azeotrope - An azeotrope or constant boiling mixture having two components, such as ethanol and water.

Biochemical Conversion - The use of enzymes and catalysts to change biological substances chemically to produce energy products. For example, the digestion of organic wastes or sewage by microorganisms to produce methane is a biochemical process.

Biodiesel -  Biodiesel is an alternative or additive to standard diesel fuel that is made from biological ingredients instead of petroleum (or crude oil). Biodiesel is usually made from the transesterification of plant oils or animal fat. Commonly, a blend is created of 20% biodiesel and 80% petroleum diesel, to reduce emissions (CO, CO2, aromatic hydrocarbons, SO2, particulates), reduce knocking and improve lupicity. Biodiesel is biodegradable and non-toxic, and used in transportation fleets, marine fleets and mines because of lower emissions. Biodiesel is considered to be the lowest-cost strategy in complying with state and federal regulations, as it does not require major engine modifications.

Biomass - Renewable organic matter such as agricultural crops; crop waste residues; wood, animal, and municipal waste, aquatic plants; fungal growth; etc., used for the production of energy.

Blending Plant - A facility which has no refining capability but is either capable of producing finished motor gasoline through mechanical blending or blends oxygenates with motor gasoline.

Blended Whisky - Defined by the B.A.T.F. as a mixture which contains straight whisky, or a blend of straight whiskies, at not less than 20 per cent on a proof-gallon basis, excluding alcohol derived from added harmless coloring, flavoring or blending materials, and, separately, or in combination, whisky or neutral spirits. A blended whisky containing not less than 51 per cent on a proof-gallon basis of one of the (recognized) types of straight whisky, may be further designated by that specific type of straight whisky; e.g. "Blended rye whisky."

Blender Tax Credit - A US Federal income tax credit granted to blenders of ethanol and gasoline as an alternative to the excise tax exemption.  It was originally introduced under the Crude Oil Windfall Tax Act of 1980 at a level of 40 cents per gallon, and has subsequently been changed numerous times and is currently 45 cents per gallon.

Boiler Efficiency -The thermal efficiency of a boiler in terms of the useable energy output (in the form of steam) in relationship to the energy input in the form of fuel.  Boiler efficiencies are commonly in the 70-80% range.

Boiling Point - The temperature at which the transition occurs from the liquid to the gaseous phase.  In a pure substance at a fixed pressure the boiling point does not vary.

pitish Thermal Unit (B.T.U.) - The amount of heat required to raise the temperature of one pound of water one degree Fahrenheit, under defined pressure conditions. It is the standard unit for measuring heat energy in the U.S. General conversion factors are: 1 BTU = 252 calories, 1,055 joules, or 0.293 watt hours.

poker - Anyone who executes futures or options contracts in exchange for a commission fee. The term can apply to account executives who take phone orders and pass the execution on to the floor; the term also applies to floor pokers on the NYMEX who actually execute the orders in the pit.

Bull Market (Bullish) - A market where prices are rising.

Bureau of Alcohol, Tobacco and Firearms (B.A.T.F.) - An agency of the Department of the Treasury entrusted with enforcing laws covering the production, distribution and use of alcohol, tobacco and firearms.

Butane (C4H10) - A normally gaseous straight-chain or panch-chain hydrocarbon extracted from natural gas or refinery gas streams. It includes normal butane and refinery-grade butane and is designated in ASTM Specification D1835 and Gas Processors Association Specifications for commercial butane.

Butyl Alcohol - Alcohol derived from butane that is used in organic synthesis and as a solvent.

Bushel - A unit of dry volume equal to 2150.42 cubic inches or 1.244 cubic feet.  When used to measure grain, bushel weight depends on the type and condition of the grain.  In the case of corn, bushel volume generally averages about 56 lbs. by weight.  This has lead to the use of a distillers bushel, which represents 56 lbs. of grain, regardless of type or volume.

Butanol (Butyl Alcohol) - A minor constituent of fusel oil. Chemical formula C4H9OH. Four isomers exist. They are all colorless, toxic flammable liquids. n-Butanol may be produced as a co-product with acetone and ethanol by the fermentation of selected carbohydrates with the anaerobic bacterium Clostridium acetobutylicum. Butanols are used as solvents and chemical intermediates.

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C-store - Literally, short for convenience store, but also applying to retail gasoline outlets which sell convenience goods such as milk, cigarettes, soft drinks and pead.

California Air Resources Board (CARB) - The state agency that regulates the air quality in California. CARB standards are often stricter than federal standards.

Call Option - Also referred to simply as a "call." Refers to an option which gives the buyer the right, but not the obligation, to buy a futures contract at a specific strike price.

Canola: The high oil yield plant that can be used for biodiesel fuelstock. Through a refining process, canola is crushed and the oil is reacted with methanol to produce biodiesel.

Cap - Risk management program which, usually in exchange for an up front premium, offers a price ceiling for various size purchases of fuel. Caps are most commonly offered from suppliers who utilize petroleum futures options.

Captive Refinery Oxygenate Plants - Oxygenate production facilities located within or adjacent to a refinery complex.

CARB Diesel - Term which refers to the diesel standard mandated for sale by the California Air Resources Board. It includes tough standards for sulfur and for very low aromatics.

Carbon Dioxide (CO2) - A colorless non-flammable gas. Composition CO2. It does not support human respiration, and in high concentrations it causes asphyxiation. It is approximately 1.5 times the weight of air, and tends to accumulate in floor drains, pits and in the bottoms of unventilated tanks. It is produced by various means, notably the combustion of fuels in an excess of air, and is a byproduct of yeast fermentation. It may be recovered from fermentations and compressed to a liquid or solid ("dry-ice"). A product of combustion that has become an environmental concern in recent years. CO2 does not directly impair human health, but is a greenhouse gas that traps the Earth's heat and contributes to the potential for global warming.

Carbon Monoxide (CO) - A colorless, odorless gas produced by the incomplete combustion of fuels with a limited oxygen supply, as in automobile engines. According to the U.S. Environmental Protection Agency, CO contributes to the formation of smog ground-level ozone, which can trigger serious respiratory problems.

Carbon residue - This measures the carbon-depositing tendency of a fuel and is an approximation of the ten­dency for carbon deposits to form in an engine. For conventional diesel fuel, the carbon residue is measured on the 10% distillation residue. Because B100 boils entirely at the high end of the diesel fuel range and in a very narrow temperature range, it is difficult to leave only a 10% residual when distilling biodiesel. So, bio-diesel carbon residue specifies that the entire biodiesel sample be used rather than the 10% distilled residue.

Carbon Sequestration - The absorption and storage of CO2 from the atmosphere by the roots and leaves of plants; the carbon builds up as organic matter in the soil.

Carcinogens - Chemicals and other substances known to cause cancer.

Caribbean Basin Initiative (C.B.I.) - The program arising from the Caribbean Basin Economic Recovery Act passed by the US Congress in 1983 to encourage industrial development in the Caribbean Islands and Central America.  Under this program, fuel ethanol and other products from the region may enter the US without being subject to customs duties.

Carload - Shipment of freight required to fill a rail car.

Cash Market (Also Spot Market) - High volume (25,000 to 300,000 bbls) contractual agreements between oil companies dictating delivery of petroleum products or crude oil in the near future for an established sales price. Since this market reacts quickly, and is an alternative to wholesale sales, it provides a good indication of the direction of wholesale price trends.

Cassava - A root crop with a high starch content, grown in the tropics and sub-tropical regions. Known in pazil as "manioc", it is used there as an alternative to sugar cane, as a feedstock for ethanol production. It is also processed for food as "tapioca."

Catalyst - A substance whose presence changes the rate of chemical reaction without itself undergoing permanent change in its composition. Catalysts may be accelerators or retarders. Most inorganic catalysts are powdered metals and metal oxides, chiefly used in the petroleum, vehicle, and heavy chemical industries.

CBI - See Caribbean Basin Initiative.

CBOB - Conventional gasoline blendstock intended for blending with oxygenates downstream of the refinery where it was produced. CBOB must become conventional gasoline after blending with oxygenates. Motor gasoline blending components that require blending other than with oxygenates to become finished conventional gasoline are reported as All Other Motor Gasoline Blending Components. Excludes reformulated blendstock for oxygenate blending(RBOB).

CCC - An abpeviation for Commodity Credit Corporation.

CDA - An abpeviation for Completely Denatured Alcohol.

Cellulose - The principal polysaccharide in living plants.  It forms the skeletal structure of the cell wall, hence the name.  It is a polymer of glucose units coupled by b-type linkages into chains of 2,000-4,000 units.  Cellulose normally occurs with other polysaccharides and hemicelluloses derived from sugars such as xylose, arabinose and mannose.

Cellulosic ethanol - Cellulosic ethanol or cellanol is ethanol fuel produced from cellulose, a naturally occurring complex carbohydrate polymer commonly found in plant cell walls. Cellulosic ethanol is chemically identical to ethanol from other sources, such as corn or sugar, and is available in a great diversity of biomass including waste from urban, agricultural, and forestry sources. However, it differs in that it requires an extra processing step called cellulolysis -- peaking cellulose down into sugars. Cellulosic ethanol has been for sale commercially since 2004.

Celsius (or Centigrade) - A temperature scale in which (at normal atmospheric pressure), water freezes at zero degrees and boils at 100 degrees.

Centrifuge - A machine for separating insoluble liquids or solids from liquids by the application of centrifugal force.  The two main types of centrifuges are filter and sedimenter.  In filtering centrifuges, solids are retained in a rotating perforated basket while liquids pass through the perforations.   In sedimenting centrifuges, the mixture is thrown against the solid-walled cylinder and the heavier solid particles collect against the wall for removal while the lighter liquid collects in the center part.  Centrifuges are commonly used in ethanol plants for yeast recover and in the stillage dewatering.

Cetane number - An adequate cetane number is required for good engine performance. Conventional diesel must have a cetane number of at least 40 in the United States. Higher cetane numbers help ensure good cold start properties and minimize the formation of white smoke. The ASTM limit for B100 cetane number is set at 47, because this is the level identified for “Premium Diesel Fuel” by the National Conference of Weights and Measures. Also, 47 has been the lowest cetane number found in U.S. biodiesel fuels. The cetane index (ASTM D976) is not an accurate predictor of cetane number for biodiesel or biodiesel blends, because it is based on a calculation that uses specific gravity and distillation curve, both of which are different for biodie­sel than for petroleum diesel.

Chemical formula ClO2 - It is a strongly-oxidizing, yellow-to-reddish-yellow gas at room temperatures. It has an unpleasant odor, similar to that of chlorine, and reminiscent of that of nitric acid. It is unstable in light. It reacts violently with organic materials and is easily detonated by sunlight or heat, in concentrations greater than 10 per cent at atmospheric pressure. Boils at 11°C and freezes at -59°C. Chlorine dioxide may be used as a sterilant, and may be produced in sit Chlorine Dioxide - u for sterilizing yeast mashes, by addition of sodium chlorite solution in the presence of acids or chlorine (or hypochlorite solution). It is considerably more effective as a sterilant than straight chlorine.

Chromatography - A method of separating a mixture of chemical compounds by selective distribution between two immiscible materials (or phases), one stationary and the other mobile.  The phases are selected so that the mobile phase will carry the various components through the stationary (or solid) at differing rates to given separation.  Gas chromatography may be used to separate ethanol from the other congeners produced in fermentation and to measure them quantitatively.  High performance liquid chromatography may be used to follow starch hydrolysis in grain alcohol production.

Class I - VIII Trucks (Classification by Gross Vehicle Weight):

Class GVW

I 6,000 lbs. or less

II 6,00 1 - 10,000 lbs.

III 10,001-14,000 lbs.

IV 14,001-16,000 lbs.

V 16,001-19,500 lbs.

VI 19,501-26,000 lbs.

VII 26,001-33,000 lbs.

VIII 33,001 lbs. or more

Clean Air Act (CAA) - Signed into law in 1963, then amended in 1970, and again in 1990 (see Clean Air Act Amendments of 1990). Includes emissions standard for mobile and stationary sources. Enforced by the U.S. Environmental Protection Agency.

Clean Air Act Amendments of 1990 (CAAA) - Amendments to the Clean Air Act of 1970. The Clean Air Act Amendments of 1990 created two new gasoline standards designed to reduce harmful fuel emissions for vehicles in highly polluted cities. The Act required gasoline to contain cleaner burning additives called fuel oxygenates such as ethanol. This Act recognized that changes in motor fuels and fuel composition would play a vital role in reducing pollution from motor vehicle exhaust.

Clean Diesel - An evolving definition of diesel fuel with lower emission specifications, which strictly limit sulfur content to 0.05 weight %; in California, aromatics content is further limited to 10 volume % (for large refiners).

Clearing Member - Term which applies to a member or a member firm of the NYMEX who has met the capital requirements to become a member of the clearing house and can accept and manage trades executed on the floor. All trades have to eventually go through a clearing member, and it is the member's ultimate responsibility to guarantee performance.

Close - The short period at the end of a futures trading session each day at which the closing price range is established.

Closed-Loop Carburetion - System in which the fuel/air ratio in the engine is carefully controlled to optimize emissions performance. A closed-loop system uses a fuel metering correction signal to optimize fuel metering.

Cloud point - This is the most commonly used measure of low-temperature operability; fuels are generally expected to operate at temperatures as low as their cloud point. The B100 cloud point is typically higher than the cloud point of conventional diesel. Cloud point must be reported to indicate biodiesel’s effect on the final blend cloud point. Low-temperature properties and strategies for ensuring good low-temperature performance of biodiesel blends are discussed in more detail in later sections.

Cold soak filterability - This is the newest requirement. It was added in 2008 in response to data indicating that some B100 could, in blends with petroleum diesel of up to 20%, form precipitates above the cloud point. B100 meeting the cold soak filterability requirements does not form these precipitates. This, along with cloud point, is needed to predict low-temperature operability.

Co-solvents - Heavier molecular weight alcohols used with methanol to improve water tolerance and reduce other negative characteristics of gasoline/alcohol blends. Tertiary butyl alcohol (TBA) was used commercially as a co-solvent for methanol/gasoline blends during the 1980s.

COFC - Container on (rail) flat car. A form of intermodal movement of freight.

Cold Filter Plug Point - The temperature at which fuel crystals cause a fuel filter to plug (commonly referred to as gelling-up).

Collar - Term which refers to a futures or derivatives program where the buyer locks in a price ceiling, but also a price floor. A trucking company which caps its autumn price at 60cts gal but only shares in downward moves to 50cts/gal has utilized a "collar" program from its supplier.

Column - A vertical cylindrical vessel containing a series of perforated plates or other contact devices through which vapors may pass to effect a separation of liquid mixtures by distillation.

Commercials - Oil companies, as opposed to speculators. Usually involved in a futures environment.

Commingling - Term which generally applies to the mixing of two petroleum products with similar specifications. Most panded gasoline firms require that their product not be commingled to preserve the integrity of the pand.

Co-Mingled Tank - The term used for fuel-ethanol tanks at refineries or pipeline terminals, where two or more suppliers may share the same tank for storing their ethanol. (This necessitates the tank owner or operator establishing quality standards for product put into the tank.)

Commission House - Term for the entities which buy and sell actual futures contracts for customers in exchange for a commission. Also known in the trade as a futures commission merchant or FCM.

Completely-Denatured Alcohol (C.D.A) - A term used by the B.A.T.F. to describe ethanol which has been made unfit for human consumption by addition of specified denaturants such as methyl-isobutyl-ketone, kerosene or gasoline.

Common Carrier - A pipeline or transport company which has government authority to move product for hire, operating like a public utility with standard rates for various shipments.

Compression Ignition - The form of ignition that initiates combustion in a diesel engine. The rapid compression of air within the cylinders generates the heat required to ignite the fuel as it is injected.

Congeners - Chemical compounds which are produced together with ethanol in the fermentation process. They are frequently referred to as "impurities". Common congeners are methanol, acetaldehyde, esters (such as ethyl acetate), and fusel oils, (higher alcohols, particularly amyl alcohols.) Fermentation conditions may be adjusted to control congener formation, depending on the requirements for the end product.

Congested Market - A period of repetitious and limited price fluctuations within a tight trading range.

Contango - Term that describes a market which features higher prices for more distant delivery of futures contracts. If prompt crude is $18 bbl and delivery two months hence is $19 bbl, the market is said to be in contango. A market in severe contango can often suggest a specification change or a complete lack of storage.

Continuous Cooker - A system into which a mash of water, grain and enzymes may be fed continuously, to be cooked and discharged to the fermentation system. Continuous cookers generally consist of a slurry tank connected by a pump to a steam-jet heater, a holding vessel or lengths of piping (to provide some residence time at the cooking temperature), one or more flash vessels (to cool the cooked mash) a holding vessel for enzymic liquefaction, and a heat exchanger for final mash cooling. Continuous cookers are more common in fuel-ethanol plants than in beverage-alcohol plants.

Continuous fermentation - A system into which cooked mash may be fed continuously to be fermented and then discharged to the beer well and distillation system.  Continuous fermentation systems generally consist of a series of interconnected tanks sized to provide sufficient residence time for the fermentation to proceed to completion.  The ethanol industry is divided on fermentation systems, with more gallonage produced by batch fermentation than continuous fermentation.

Continuous distillation - A process using specially designed equipment to permit a volatile component such as ethanol to be separated by distillation from a continuous flow of an aqueous solution such as beer.

Cooker - A device for heating a slurry of grain and water to a sufficiently high temperature for sufficient time to release and gelatinize the starch in the grain and thereby render it susceptible to enzymatic hydrolysis.  Live steam is normally used for heating the slurry; and pumps and agitators are used to ensure mixing and even heating.  Cooking may be performed continuously or in a batch mode.

Cooling tower -  A tower or other type of structure where air (the heat receiver) circulates in direct or indirect contact with warmer water (the heat source) to cool the water.  Cooling towers are used in ethanol production plants to recirculate cooling water and to minimize the amount of water used from wells, rivers or public sources.

Cooperative Research and Development Agreement (CRADA) - Federal and private joint research and development program that is used to further technology commercialization.

Copper strip corrosion test - This test is used to indicate potential difficulties with copper and ponze fuel system components. The requirements for B100 and conventional diesel are identical, and biodiesel meeting other D6751 specifications always passes this test. Copper and ponze may not corrode in the presence of biodiesel fuel, but prolonged contact with these catalysts can degrade the fuel and cause sediment to form.

Corporate Average Fuel Economy (CAFE) - Law passed in 1975 that set federal fuel economy standards (P.L. 94-163). The CAFE values are an average of city and highway fuel economy test results weighted by a manufacturer for either its car or truck fleet. CAFE is also a program created to determine whether vehicle manufacturers are complying with the gas mileage, or fuel economy, standards set by the federal government. The CAFE values are obtained by combining the city and highway fuel economy test results and computing an average that is weighted by vehicle sales.

Correlation Coefficient - A statistical factor measuring how well any two markets (i.e. a cash market and a futures market) move in unison. A correlation coefficient of 1 would indicate a perfect 1-to-1 relationship.

Corrosion Inhibitors - Additives used to inhibit corrosion (e.g., rust) in the fuel system.

Cost of Carry - The cost to physically store crude or petroleum products, including storage fees, insurance, inspections and capital costs.

Cover - To close out a long or short futures position.

CPO (Commodity Pool Operator) - Term which applies to a concern which pools money to trade commodities. The commodities version of a mutual fund.

Crack Spread - Term applied to the differential between what a typical refined products mix would yield, and the value of crude. The common crack spread features a per bbl reference derived of 66.6% unleaded gasoline and 33.4% No. 2 oil. The resulting average is compared to the WTI number for the resulting "crack spread."

Current Delivery Month - The futures contract date closest to expiration. Contracts are usually referred to by month (i.e. September Crude refers to crude contracts that are to be delivered in September.

Cyclohexane - A colorless, flammable, alicyclic hydrocarbon liquid, of chemical formula C6H12, which boils at 80.3°C, and freezes at 6.5°C. It is used as an alternative to benzene as an entrainer in the dehydration of ethanol by azeotropic distillation.

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DDG - Abpeviation for distillers dried grain.

DDGS - Abpeviation for distillers dried grain with soluble.

Dealer Tank Wagon (D.T.W.) - Used in reference to fuel ethanol and gasoline sales.  It is generally of 7,000-8,000 gallons capacity.

Decanter - Vessel used for the separation of two-phase liquids. In a fusel-oil decanter, an upper fusel-oil phase is separated from a lower aqueous-ethanol phase. In a benzene-column reflux decanter, the upper, mainly-benzene phase is separated from the lower, mainly-water phase. See Phase Separation.

Dehydration -The process of removing water from a substance, particularly the removal of most of the remaining 5 per cent of water from 190° proof ethanol, in the production of absolute or anhydrous ethanol.

Denaturant - A substance added to ethanol to make it unfit for human consumption, so that it is not subject to taxation as beverage-alcohol. The B.A.T.F. permits the use of 2 - 5 per cent of unleaded gasoline (or similar, specified substances) for use as denaturants for fuel ethanol. (See also specially-denatured alcohol and completely-denatured alcohol.)

Demethylizing Column - Occasionally referred to as a supplementary column, it is a fractionating column to remove methanol in the production of neutral spirit and is located after the rectifying column.  The demethylizing column is heated indirectly via reboiler.  The impure spirit enters part way up the column and the methanol is removed in the overhead vapor together with some ethanol, while the bulk of the ethanol descends to be removed at the base of the column as a product relatively free of methanol.

Denatured Alcohol - Ethanol that contains a small amount of a toxic substance, such as methanol or gasoline, which cannot be removed easily by chemical or physical means. Alcohols intended for industrial use must be denatured to avoid federal alcoholic beverage tax.

Department of Energy - See U.S. Department of Energy (DOE).

Detergent - Additives used to inhibit deposit formation in the fuel and intake systems in automobiles.

Dextrose - An alternative name for glucose.

Dextrose Equivalent (D.E.) - A measure of the degree of hydrolysis or saccharification of starch. It is no longer considered as significant as previously in ethanol production, with the more general acceptance of simultaneous saccharification and fermentation.

Distillation - The process by which the components of a liquid mixture are separated by differences in boiling point by boiling and recondensing the resultant vapors.  In ethanol production, it is the primary means of separating ethanol from aqueous solutions.

Distilled spirits permit (DSP) - A permit issued by the BATF allowing the holder to engage in the production or warehousing of Undenatured ethanol for beverage, industrial or fuel use.

Distillers Bushel - 56 lbs of any grain, regardless of volume.

Distillers Dried Grain (D.D.G.) - The dried residual by-product of a grain-fermentation process. It is high in protein, as most of the grain starch has been removed. It is used as an animal-feed ingredient. By strict definition, D.D.G. is produced only from the solids separated from whole stillage by centrifuging or screening. In practice, the term is commonly used to describe the entire dried-stillage residue, making it synonymous with D.D.G.S.

Distillers Dried Grain with Solubles (D.D.G.S.) - The product derived by separating the liquid portion (thin stillage or solubles) from grain whole stillage by screening or centrifuging, then evaporating it to a thick syrup and drying it together with the grain solids portion.

Distillation Curve - The percentages of gasoline that evaporate at various temperatures. The distillation curve is an important indicator for fuel standards such as volatility (vaporization).

Dry Degermination - A process for the removal of germ from grain without the need for steeping and wet milling. It may involve some pretreatment of the grain to raise the moisture content before processing. It is used in Scotland for corn milling in grain-whisky plants, and is used in the production of corn flakes, but is not commonly used in the U.S. ethanol- production industry.

Dry milling - In the ethanol production industry dry milling refers to the milling of whole dry grain where, in contrast to wet milling, no attempt is made to remove the fractions such as germ and pan.  It may be carried out with various types of equipment, including hammer mills and roller mills.

DSP - Abpeviation for Distilled Spirits Permit.

DTW - Abpeviation for Dealer Tank Wagon.

Dual-Fuel Vehicle - Vehicle designed to operate on a combination of an alternative fuel and a conventional fuel. This includes (a) vehicles that use a mixture of gasoline or diesel and an alternative fuel in one fuel tank, commonly called flexible-fuel vehicles; and (b) vehicles capable of operating either on an alternative fuel, a conventional fuel, or both, simultaneously using two fuel systems. They are commonly called bi-fuel vehicles.

Dual-Fuel Vehicle (EPAct definition) - Vehicle designed to operate on a combination of an alternative fuel and a conventional fuel. This includes vehicles using a mixture of gasoline or diesel and an alternative fuel in one fuel tank, commonly called flexible-fueled vehicles; and vehicles capable of operating either on an alternative fuel (usually compressed natural gas or propane), a conventional fuel, or both, simultaneously using two fuel systems. These are commonly called bi-fuel vehicles.

DWG - Abpeviation for distillers wet grain.

Dynamometer - An instrument for measuring mechanical force, or an apparatus for measuring mechanical power (as of an engine).

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E10 (Gasohol) - Ethanol mixture that contains 10% ethanol, 90% unleaded gasoline.

E85 - Ethanol/gasoline mixture that contains 85% denatured ethanol and 15% gasoline, by volume.

E93 - Ethanol mixture that contains 93% ethanol, 5% methanol and 2% kerosene, by volume.

E95 - Ethanol/gasoline mixture that contains 95% denatured ethanol and 5% gasoline, by volume.

Electronic Trading - A futures trading system that automatically matches buyers and sellers through a computerized system, as opposed to the current open outcry system.

Electric Vehicle - A vehicle powered by electricity, generally provided by batteries. EVs qualify in the zero emission vehicle (ZEV) category for emissions.

Electricity - Electric current used as a power source. Electricity can be generated from a variety of feedstocks, including oil, coal, nuclear, hydro, natural gas, wind, and solar. In electric vehicles, onboard rechargeable batteries power electric motors.

Emission Standards - Limits or ranges established for pollution levels emitted by vehicles as well as stationary sources. The first standards were established under the 1963 Clean Air Act. Emission limits are imposed on four classes of vehicles: automobiles, light-duty trucks, heavy-duty gasoline trucks, and heavy-duty diesel trucks.

Ending Stocks -Primary stocks of crude oil and petroleum products held in storage as of 12 midnight on the last day of the month. Primary stocks include crude oil or petroleum products held in storage at (or in) leases, refineries, natural gas processing plants, pipelines, tank farms, and bulk terminals that can store at least 50,000 barrels of petroleum products or that can receive petroleum products by tanker, barge, or pipeline. Crude oil that is in-transit by water from Alaska, or that is stored on Federal leases or in the Strategic Petroleum Reserve is included. Primary Stocks exclude stocks of foreign origin that are held in bonded warehouse storage.

End User - The ultimate consumer of petroleum products; most commonly used in connection with large industrial or utility consumers.

Endo-Enzyme - An enzyme which acts on internal portions of a large polymeric molecule rather than around the periphery. For example, the alpha amylase enzyme hydrolyses linkages within amylose and amylopectin molecules, as an endo-enzyme. In contrast amyloglucosidase acts as an exo-enzyme in only hydrolyzing the outermost linkages.

Energy Information Administration (EIA) - A division of the Department of Energy that compiles data on petroleum supply and demand on a weekly and monthly basis. These figures are not as timely as API statistics, but are considered more accurate.

Energy Policy Act of 1992 (EPAct) - Passed by Congress to enhance U.S. energy security by reducing our dependence on imported oil. It mandates the use of alternative fuel vehicles, beginning with federal, then state, then fuel provider fleets.

Energy/Fuel Diversity - A policy that encourages the development of energy technologies to diversify energy supply sources, thus reducing reliance on conventional (petroleum) fuels; Energy/fuel diversity applies to all energy sectors.

Energy/Fuel Security - A policy that considers the risk of dependence on fuel sources located in remote and unstable regions of the world. It also considers the benefits of domestic and diverse fuel sources.

Entrainer – A substance used to assist in the dehydration of ethanol by azeotropic distillation.  Examples are benzene, cyclohexane, and pentane.

Environmental Protection Agency - See U.S. Environmental Protection Agency (EPA)

Enzymatic Hydrolysis - The hydrolysis of a polymer by the use of enzymes. In the case of starch hydrolysis, an alpha amylase enzyme may be used in the initial hydrolysis to achieve liquefaction, and an amyloglucosidase enzyme may be used to complete the hydrolytic saccharification to fermentable sugars.

Enzyme – Any of a class of complex proteinaceous substances (such as amylases and lactases) produced by living organisms that catalyze chemical reactions without being destroyed.  Enzymes may act outside the producing organism and may be use in industrial process such as saccharification.

Ester - An organic compound formed by reacting an acid with an alcohol, always resulting in the elimination of water.

ETBE (Ethyl tertiary butyl ether) (CH3)3COC2H5) - An oxygenate blend stock formed by the catalytic etherfication of isobutylene with ethanol.

Ethane (C2H6) - A colorless hydrocarbon gas of slight odor having a gross heating value of 1,773 Btu per cubic foot. It is a normal constituent of natural gas.

Ethanol (also known as Ethyl Alcohol, Grain Alcohol, CH 3 CH 2 OH) - Can be produced chemically from ethylene or biologically from the fermentation of various sugars from carbohydrates found in agricultural crops and cellulosic residues from crops or wood. Chemical formula: C2H5OH. It has a boiling point of 78.5°C in the anhydrous state.  However, it forms a binary azeotrope with water, with a boiling point of 78.15°C at a composition of 95.57 per cent by weight ethanol.  Used in the United States as a gasoline octane enhancer and oxygenate, it increases octane 2.5 to 3.0 numbers at 10% concentration. Ethanol also can be used in higher concentration in alternative fuel vehicles optimized for its use.

Ether - A generic term applied to a group of organic chemical compounds composed of carbon, hydrogen, and oxygen, characterized by an oxygen atom attached to two carbon atoms (e.g., methyl tertiary butyl ether).

Etherification - Oxygenation of an olefin by methanol or ethanol. For example, MTBE is formed from the chemical reaction of isobutylene and methanol.

Ethyl Alcohol - See Ethanol.

Ethyl Ester - A fatty ester formed when organically derived oils are combined with ethanol in the presence of a catalyst. After water washing, vacuum drying, and filtration, the resulting ethyl ester has characteristics similar to petroleum-based diesel motor fuels.

Ethyl Tertiary Butyl Ether (ETBE) - A fuel oxygenate used as a gasoline additive to increase octane and reduce engine knock.

Exchange of Futures for Physicals (EFP) - Another means of making delivery in the futures market. EFP's would allow for a delivery of physical product that doesn't necessarily conform to NYMEX specifications (delivery at say, Baltimore). Terms can vary across a poad spectrum including location, time, and product specifications.

Extractive Distillation - A process in which a substance referred to as an extractant is added to a mixture being distilled, to change the volatility of one or more components. The less-volatile mixture will then descend in a continuous-distillation column, while the more volatile components may be removed in the condensed overhead vapors. In the use of extractive distillation in the dehydration of ethanol, liquid extractants such as ethylene glycol, or glycerol may be used. Salts such as potassium and sodium acetates may also be used alone in molten form, or in mixtures with glycerol etc. Anhydrous ethanol is recovered in the overhead condensate, while the water combines with the extractant to emerge from the bottom of the column. (This is the reverse of the situation in azeotropic distillation, as with benzene, etc.) The extractant is then separated from the water in another column (or an evaporator) and is recycled.

In the production of neutral spirit, light rums or whiskies, extractive distillation may be used to remove fusel oils and some other congeners in the condensed overhead vapors. In this instance, the extractant is water, as some of the congeners which have a lower volatility than ethanol in a concentrated state, may have a higher volatility than ethanol when diluted with water, so that they rise up the extractive distillation column, while the ethanol descends.

Evaporator - A device used to evaporate part or all of a liquid from a solution.  In the case of grain stillage processing, evaporators may be used to concentrate screened thin stillage to a syrup of about 35% solids, which may then be fed to a dryer.  Evaporators are normally operated under a vacuum (to obtain a lower boiling point of the liquid) and may consist of a series of interlinked vessels or effects operating under differing degrees of vacuum.

Evaporative Emissions - Hydrocarbon vapors that escape from a fuel storage tank or a vehicle fuel tank or vehicle fuel system.

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FAME - Another name for biodiesel.

Facultative Anaerobe - Term used to describe a microorganism such as a yeast, which is essentially aerobic (or air-requiring), but can also thrive under anaerobic (or air-free) conditions.

Fatty acid methyl ester (FAME) - Fatty acid methyl ester or (FAME) is another name for biodiesel .

Fahrenheit Scale - A temperature scale in which the boiling point of water is 212°F and the freezing point is 32°F. (The zero point was originally established as the lowest point obtainable with a mixture of equal weights of snow and common salt.)

Farmers Home Administration (FmHA) - A division of the US Department of Agriculture which among other activities is empowered to make loan guarantees for the establishment of ethanol production plants.

Feed Plate (or Feed Tray) - The plate or tray onto which the distilland (liquid to be distilled) is introduced in a distillation column. In theory, it is the point in a column above which enrichment or concentration occurs, and below which stripping occurs.

Feedstock - The raw material used in a process.  For example, corn, molasses, whey, etc. may be used as feedstocks for ethanol production.

Fermentable Sugars - Simple sugars such as glucose and fructose that can be converted into ethanol by fermentation with yeast.  They may be derived by the hydrolysis of starch or cellulose feedstocks or obtained from other sources.

Fermentation - The enzymatic transformation by microorganisms of organic compounds such as sugar. It is usually accompanied by the evolution of gas as the fermentation of glucose into ethanol and CO2.

Fermentation Efficiency - The measure of the actual output of a fermentation product such as ethanol, in relation to the theoretically-obtainable yield.

Fermenter - The vessel in which the process of mash fermentation takes place. The vessel may be fapicated from steel, fiberglass, etc., and is normally fitted with an internal or external cooling system for controlling the temperature of the fermenting mash.

Fischer-Tropsch - A method discovered in 1923 by the German coal researchers Franz Fischer and Hans Tropsch, for the synthesis of hydrocarbons and other aliphatic compounds. A mixture of hydrogen and carbon monoxide is reacted in the presence of an iron or cobalt catalyst. Much heat is evolved and products such as methane, synthetic gasoline and waxes, and alcohols are made. Water or carbon dioxide is its by-product.

Flash Point - The minimum temperature at which a combustible liquid will ignite when a flame is introduced.  It depends on the volatility of the liquid to provide sufficient vapor for combustion.  For example anhydrous ethanol has a flash point of 51 Deg. F., 90 Deg. Proof ethanol has a flash point of 78 Deg. F.

Flash point (in Biodiesel) - A minimum flash point for diesel fuel is required for fire safety. B100’s flash point is required to be at least 93ºC (200ºF) to ensure it is classified as nonhazardous under the National Fire Protection Asso­ciation (NFPA) code.

Flexible-Fuel Vehicle (FFV) - A Vehicle with a common fuel tank designed to run on varying blends of unleaded gasoline with either ethanol or methanol.

Floor poker - An exchange member who executes orders for futures contracts in the trading pit.

Floor Trader - A trader in a futures pit that executes trades solely for his own account.

Fluidized-Bed-Combustion Boiler -  A boiler in which the coal or other fuel particles are kept in suspension by a rising column gas rather than resting on a conventional grate.  The system gives greater heat transfer and higher potential combustion efficiency.  The system has the advantage that limestone may be added to the coal fuel to absorb sulfur gases to reduce emissions.

FOB - Terms of a transaction where the seller agrees to make the product available within an agreed-upon time period at a given location free on board carrier. Any subsequent costs are the responsibility of the buyer.

Force Majeure - The legal cancellation of a delivery obligation due to the occurrence of natural acts beyond the direct control of the seller (i.e., operating problems with tankers or refineries or weather disruptions).

Forward Market - Cash market (non-exchange) commitment to delivery of petroleum products or crude at a set price for future delivery (i.e., a fixed price contract).

Fossil Fuel - A fuel such as coal, oil, and natural gas. Fossil fuels are the remains of ancient plants and animals.

Fractions - The different cuts of petroleum products that come off a distillation column contingent on their volatility or boiling range.

Fractional Distillation - A process of separating mixtures such as ethanol and water, by boiling and drawing off the condensed vapors from different levels of the distillation column.

Freight Forwarder - An individual or company that accepts less-than-truckload (LTL) or less-than-carload (LCL) shipments from shippers and combines them into carload or truckload lots. Designated as a common carrier under the Interstate Commerce Act.

Front-running - Illegal practice where a floor poker executes an order for his own account before executing an order for a customer, with the intent of getting ahead of a market move precipitated by the customer's order. A poker who went long 10 contracts of December crude just before he executed a buy order for 500 contracts would be "front-running." The audit trail, which timestamps when orders are received, etc., is intended to make this practice difficult to get away with.

Fructose (or Levulose) - A fermentable monosaccharide, or simple, single-unit sugar, of the chemical formula C6H12O6. Its chemical structure is similar to that of glucose, but it has the distinction of being sweeter to the taste. It may be produced from glucose by enzymatic isomerization, as in the production of high-fructose corn syrup (HFCS).

Fuel Cell - An electrochemical engine with no moving parts that converts the chemical energy of a fuel, such as hydrogen, and an oxidant, such as oxygen, directly to electricity. The principal components of a fuel cell are catalytically activated electrodes for the fuel (anode) and the oxidant (cathode) and an electrolyte to conduct ions between the two electrodes.

Fuel Ethanol (C2H5OH) - Usually denotes anhydrous ethanol or motor-fuel-grade ethanol which is an aliphatic alcohol which has been denatured by addition of 2 - 5 per cent unleaded gasoline, and which is intended for use as an automotive fuel in blends with gasoline.

Fundamentals - Pricing analysis based on supply and demand factors for any particular market.

Fundamental Analysis - Analysis derived from actual supply and demand factors such as inventories, refinery operations, physical buying patterns, or disruptions in the supply and distribution chain. Contrasts with technical analysis.

Fusel Oil - Term used to describe the higher alcohols, generally the various forms of propanol, butanol and amyl alcohol, which are congeners, or by-products of ethanol fermentation. Normally, predominantly iso-amyl alcohol. Their presence in alcoholic beverages is known to be a cause of headaches and hangovers. The fusel oils have higher boiling points than ethanol and are generally removed in the distillation process, to avoid accumulations in the rectifier. They may be subsequently added back into the anhydrous product for motor-fuel-grade ethanol.

Futures - A standardized contract for the future purchase or sale of a commodity on a formalized exchange.

Futures Margin - A deposit required of futures participants that guarantees assurance of performance. Funds are on hand to assure that the buyer or seller makes good on any losses that might accrue on his position. Margin deposits are a sort of futures performance bond.

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Galactose - A monosaccharide, of chemical formula C6H12O6, which, with glucose, is a constituent of the disaccharide lactose. It is an isomer of glucose, but is less-readily fermented by yeasts to ethanol.

Gallon - Measurement of volume in the oil industry (42 gallons=1barrel).

Gasoil -Commonly, the European term used for diesel fuel and heating oil.

Gas Chromatography - A technique for separating chemical substances in which the sample is carried by an inert gas stream through a tube (or column) packed with a finely divided solid material.  The various components of the sample pass through the column at differing velocities and emerge from the column at distinct intervals to be measured by different devices such as a flame ionization detector  or thermal conductivity detector.  (Where the solid material in the column is pretreated with a liquid to achieve the component separation , the process may be referred to as gas liquid chromatography.)  The technique may be used for separating and measuring the amount of ethanol and the various by-products formed in fermentation.

Gas-Liquid Chromatography - See Gas chromatography.

as to Liquid Technology - Gas-to-liquid conversion technologies use chemical or physical means to convert natural gas to a liquid form suitable for ready transport or direct use.

Gasohol - In the United States, gasohol (E10) refers to gasoline that contains 10% ethanol by volume. This term was used in the late 1970s and early 1980s but has been replaced in some areas of the country with E10, super unleaded plus ethanol, or unleaded plus.  Data on gasohol that has at least 2.7% oxygen, by weight, and is intended for sale inside carbon monoxide nonattainment areas are included in data on oxygenated gasoline. See Oxygenates.

Gasoline - A complex mixture of relatively volatile hydrocarbons with or without small quantities of additives, blended to form a fuel suitable for use in spark-ignition engines. Motor gasoline, as defined in ASTM Specification D 4814, is characterized as having a boiling range of 122 to 158 degrees F at the 10 percent recovery point to 365-374 degrees F at the 90 percent recovery point.     

• Conventional Gasoline - Finished motor gasoline not included in the oxygenated or reformulated gasoline categories. Note: This category excludes reformulated gasoline blendstock for oxygenate blending (RBOB) as well as other blendstock.

   • OPRG - “Oxygenated Fuels Program Reformulated Gasoline” is reformulated gasoline which is intended for use in an oxygenated fuels program control area.

   • Oxygenated Gasoline (Including Gasohol) - Oxygenated gasoline includes all finished motor gasoline, other than reformulated gasoline, having oxygen content of 2.0% or higher by weight. Gasohol containing a minimum 5.7% ethanol by volume is included in oxygenated gasoline. Oxygenated gasoline was reported as a separate product from January 1993 until December 2003 inclusive. Beginning with monthly data for January 2004, oxygenated gasoline is included in conventional gasoline. Historical data for oxygenated gasoline excluded Federal Oxygenated Program Reformulated Gasoline (OPRG). Historical oxygenated gasoline data also excluded other reformulated gasoline with a seasonal oxygen requirement regardless of season.

   • Reformulated Gasoline - Finished gasoline formulated for use in motor vehicles, the composition and properties of which meet the requirements of the reformulated gasoline regulations promulgated by the U.S. Environmental Protection Agency under Section 211(k) of the Clean Air Act. It includes gasoline produced to meet or exceed emissions performance and benzene content standards of federal-program reformulated gasoline even though the gasoline may not meet all of the composition requirements (e.g. oxygen content) of federal-program reformulated gasoline. Reformulated gasoline excludes Reformulated Blendstock for Oxygenate Blending (RBOB) and Gasoline Treated as Blendstock (GTAB). Historical reformulated gasoline statistics included Oxygenated Fuels Program Reformulated Gasoline (OPRG).

   • Reformulated (Blended with Ether) - Reformulated gasoline blended with an ether component (e.g. methyl tertiary butyl ether) at a terminal or refinery to raise the oxygen content.

Reformulated (Blended with Alcohol). Reformulated gasoline blended with an alcohol component (e.g. fuel ethanol) at a terminal or refinery to raise the oxygen content.

   • Reformulated (Non-Oxygenated) - Reformulated gasoline without added ether or alcohol components.

Gasoline Blending Components - Naphthas which will be used for blending or compounding into finished aviation or motor gasoline (e.g., straight-run gasoline, alkylate, reformate, benzene, toluene, and xylenes). Excludes oxygenates (alcohols, ethers), butane, and natural gasoline.

Gasoline Gallon Equivalent (gge) - A unit for measuring alternative fuels so that they can be compared with gasoline on an energy equivalent basis. This is required because the different f

Gay Lussac (G.L.) - The name given to a scale of the concentration of ethanol in mixtures with water, where each degree is equal to 1 per cent by volume (i.e. 1° G.L. is equivalent to 2° U.S. proof.) It takes the name from the French chemistry pioneer, Joseph-Louis Gay Lussac. The scale is used extensively in Europe, South America etc.

GC - Abpeviation for gas chromatograph.

Gelatinization - In reference to the cooking of starchy feedstocks, gelatinization is the stage in which the starch granules absorb water and lose their individual crystalline structure to become a viscous liquid gel. Gelatinization is significant in that it is the preliminary process necessary to render starch susceptible to enzymatic hydrolysis, for conversion to fermentable sugars.

Glucamylase - An enzyme which hydrolyses starch into its constituent glucose units. (See Amyloglucosidase.)

General Freight Carrier - A carrier which handles a wide variety of commodities.

GL - Abpeviation for Gay Lussac.

GLC - Abpeviation for gas-liquid chromatography.

Global Warming - The theoretical escalation of global temperatures caused by the increase of greenhouse gas emissions in the lower atmosphere.

Globex - A global automated trade execution system (see electronic trading) created by the Chicago Merc and Reuters. The New York Mercantile Exchange approved the implementation of this system to supplement pit trading after hours.

Glycerol (or Glycerine) - A clear, colorless, viscous, sweet-tasting liquid belonging to the alcohol family of organic compounds. It has a chemical formula of CH2OHCHOHCH2OH, having three hydroxyl (OH) groups. It is a by-product of alcoholic fermentations of sugars. It is hygroscopic, and may be used as an extractant in the dehydration of ethanol.

Glycerin – Free and Total (in Biodiesel) - These numbers measure the amount of unconverted or partially converted fats and by-product glycerin in the fuel. Incomplete conversion of the fats and oils into biodiesel can lead to high total glycerin. Incomplete removal of glycerin can lead to high free glycerin and total glycerin. If these numbers are too high, the storage tank, fuel system, and engine can be contaminated. Fuels that exceed these limits are highly likely to plug filters and cause other problems. One of the major shortcomings of the D6584 gas chromatograph (GC) method is its sensitivity to diesel fuel. Diesel fuel components react dif­ferently on the column used in the GC—they make the determination of free glycerin very difficult and may damage the column. Thus, many labs are unable to determine free and total glycerin by this method in samples with even small amounts of diesel fuel, such as B99.9.

Grain Sorghum - (Otherwise known as "milo"), a sorghum grown for grain production, as distinct from sweet sorghum grown for the sugar content of its stem. It may be used as a feedstock for ethanol production.

Greenhouse Effect - A warming of the Earth and its atmosphere as a result of the thermal trapping of incoming solar radiation by CO2, water vapor, methane, nitrogen oxide, chlorofluorocarbons, and other gases, both natural and man-made.

Gross Average - An average of all suppliers, calculated without the deduction of any pre-payment terms.

Gross Combination Weight (GCW) - The maximum allowable fully laden weight of a tractor and its trailer(s).

Gross Domestic Product - A measure of the money value of the goods and services becoming available to the nation from economic activity within the United States.

Gross Vehicle Weight Rating (GVWR) - Maximum weight of a vehicle, including payload.

Group III Market - Spot market vernacular for a Midwest delivery. It specifically entails delivery on Williams Pipeline at Tulsa, Okla., but more generally encompasses Oklahoma, Missouri, Kansas, Iowa, Nepaska, Minnesota, South Dakota and North Dakota.

Gulf Coast Spot Market - Large volume transactions (from 25,000 barrels to full tankers of petroleum products) bought or sold for a stipulated delivery in the near future. Although this market might entail several pipeline or waterborne transaction points in the Texas and Louisiana area, unless specified otherwise, it reflects the delivery of the product the same month at a Pasadena, Texas, origin on Colonial Pipeline.

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Hammer Mill - A type of impact mill or crusher in which materials such as cereal grains are reduced in size by hammers revolving rapidly in a vertical plane within a steel casing.  A screen with numerous holes of a selected diameter is installed in the casing to control the size of particles produced.  It is commonly used for grinding corn as a fermentation feedstock.

Heads - Term used to describe the impurities produced in ethanol fermentations ("congeners"), which have lower boiling points than ethanol. They include methanol and aldehydes.

Heads-concentrating column - A distillation column used to concentrate heads removed in the production of neutral spirit, light rums and whiskies.

Heating Oil - A distillate used for home or commercial heating. Widely used as a synonym for No. 2 fuel oil or diesel.

Heavy Duty Truck - Truck with a gross vehicle weight generally in excess of 19,500 pounds (Class VI VIII). Other minimum weights are used by various laws or government agencies.

Hedger - Oil industry participant who takes a futures, options, or derivatives position opposite that of a position held in the cash or contract market. A refiner who sells 500 forward gasoline contracts against his future production is hedging. A hedger is looking to reduce risk in exchange for a guaranteed margin, but he may forego larger profits in reducing his exposure.

Hedging - The initiation of an opposite futures position to protect a cash market position from an adverse price movement.

High Occupancy Vehicle (HOV) Lanes - Lanes on the highway that are restricted to vehicles carrying more than one passenger.

Higher Alcohols - Alcohols having more than two carbon atoms within their molecule. They exist in various isomeric forms. As the number of carbon atoms increases, so also the number of isomers increases, but at a greater rate. The lower members of this group, namely propanol, butanol and amyl alcohol, are major constituents of fusel oil.

Highway-User Fee or Tax - A charge levied on persons or organizations based on the use of public roads. Funds collected are usually applied toward highway construction, reconstruction and maintenance. Examples include vehicle registration fees, fuel taxes and weight-distance taxes.

Historical Volatility - The annualized standard deviation of percent variation in futures prices over a specific period of time. Indicates past volatility in the marketplace.

Hypid Electric Vehicle (HEV) - A vehicle powered by two or more energy sources, one of which is electricity. HEVs may combine the engine and fuel of a conventional vehicle with the batteries and electric motor of an electric vehicle in a single drivetrain.

Hydrogen - The lightest of all gases, occurring chiefly in combination with oxygen in water; exists also in acids, bases, alcohols, petroleum, and other hydrocarbons.

Hydrolysis - Literally means the peakdown, destruction or alteration of a chemical substance by water.  In the case of starch and other polymers of glucose, a molecule of water is divided between two adjacent glucose units , in order to cleave the linkage.  For example, maltose (C12H22O11), which contains two glucose rings, requires the addition of a molecule of water (H2O) to yield two separate glucose molecules (C6H12O6),  The hydrolysis may be accomplished with the use of acids or enzymes.

Hydrometer - A direct-reading instrument for indicating the density, specific gravity or other similar characteristics of liquids. It is generally comprised of a long-stemmed glass tube with a weighted bottom, which floats at different levels in liquids of different densities. The reading is taken at the meniscus, where the calipated stem emerges from the liquid. The liquid temperature is normally determined when taking a reading, and reference is made to hydrometer tables to obtain a correction to a standard temperature. A proof hydrometer measures the content of ethanol in a mixture with water. A pix or balling hydrometer measures on a scale equivalent to the percentage of sugar by weight in an aqueous solution.

Hydroselection Column - Synonym for extractive distillation column.

Hydrocracker- An oil refining process in which light or heavy gas oils or residue hydrocarbons are mixed with hydrogen under conditions of high temperature and pressure, in the presence of a catalyst, yielding light oils.

Hydrocracking - A refining process for converting middle distillates to high octane gasoline, jet fuel, or high grade diesel through the introduction of a hydrogen catalysts under very high pressure.

Hydrotreater - A refining unit whereby processed material from the crude units are treated in the presence of catalysts and hydrogen, often to remove sulfur and other unwanted substances. The hydrotreater is often the critical unit for producing jet fuel and low-sulfur diesel.

Hygroscopic - Term used to describe a substance which has the property of absorbing moisture from the air. Anhydrous ethanol is hygroscopic, and its exposure to moist air should therefore be minimized.

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Idle Capacity - The component of operable capacity that is not in operation and not under active repair, but capable of being placed in operation within 30 days; and capacity not in operation but under active repair that can be completed within 90 days.

Imperial Gallon - A measure of volume in the pitish system, defined in 1824 as the volume occupied by 10 pounds weight of water at 62°F and 30 inches of barometric pressure. It is the equivalent of 11/5 U.S. gallons, or 4.546 liters in the metric system.

Implied Volatility - A measurement of the market's expected price range and variation for the underlying commodity futures based on market traded options premiums. Differs from historical volatility, which lists annualized standard deviation of percent changes in futures prices over a specific period.

In the Money Option (Calls) - Refers to an option where the futures price has exceeded the strike price on which it is based. An option to buy December heating oil at 60cts/gal is "in the money" when Dec. heating oil futures move above 60cts/gal. A put option for 60cts/gal would be "in the money" if the futures price is under the 60cts/gal strike price.

I.D.R.B. - Abpeviation for Industrial Development Revenue Bonds.

Industrial Alcohol - Denotes any ethanol which may be intended for industrial uses, such as solvents, extractants, antifreezes and intermediates in the synthesis of innumerable organic chemicals. The term covers ethanol of both synthetic and fermentation origin, of a wide range of qualities and proofs, with or without various denaturants.

Initial Margin - Funds required to establish a new position. Exchanges set minimums depending on volatility, market conditions, etc. and the pokerage firm may set margins above these exchange minimums. Margins for a would-be speculator are much higher than for a bona fide hedger.

Inoculum -The portion of a culture of yeast (or bacteria) which is used to start a new culture or a fermentation.

Integrated Oil Company - A company involved in all aspects of the petroleum business from wellhead crude production to retail sales of refined petroleum products.

Intercity Trucking - Trucking operations which carry freight beyond the local areas and commercial zones.

Intermodal Transportation - Transportation movement involving more than one mode (e.g. rail/motor, motor/air, or rail/water).

Intermodal Surface Transportation Efficiency Act of 1991 (ISTEA) - An omnibus act that further integrates the national intermodal surface transportation system and authorizes funds for highway construction, highway safety programs, and mass transit programs. ISTEA seeks a national intermodal surface transportation system that is economical, energy efficient, and environmentally sound. Section 1008 of the ISTEA establishes the Congestion Mitigation and Air Quality Improvement Program, which can provide funds to support alternative fuel and alternative fuel vehicle programs.

International Energy Agency (IEA) - An agency in Paris, France, which tracks energy statistics and information on an international level.

Interstate Commerce Commission (ICC) - Former motor carrier regulating authority, eliminated by the ICC Termination Act of 1995 (see DOT).

Intrinsic Value - The amount by which an options contract is in the money. A 60cts/gal call option would have 2cts/gal of "intrinsic value" if the underlying futures price were 62cts/gal.

Introducing poker (IB) - A firm that solely solicits or accepts orders for the purchase or sale of futures contracts or options.

Inverted Market - See Backwardation.

International Petroleum Exchange (IPE) - International Petroleum Exchange, based in London, is the European equivalent of the NYMEX. IPE operates an exchange which trades pent and gasoil (heating oil) futures among other energy contracts.

ISTEA - Intermodal Surface Transportation Efficiency Act of 1991.

Isobutane (C4H10) - A normally gaseous panch-chain hydrocarbon. It is a colorless paraffinic gas that boils at a temperature of 10.9 degrees Fahrenheit. It is extracted from natural gas or refinery gas streams.

Isobutylene (C4H8) - An olefinic hydrocarbon recovered from refinery processes or petrochemical processes.

Isohexane (C6H14) - A saturated panch-chain hydrocarbon. It is a colorless liquid that boils at a temperature of 156.2 degrees Fahrenheit.

Isomerization - A refining process which alters the fundamental arrangement of atoms in the molecule without adding or removing anything from the original material. Used to convert normal butane into isobutane (C4), an alkylation process feedstock, and normal pentane and hexane into isopentane (C5) and isohexane (C6), high-octane gasoline components.

Iso-Propyl Ether (I.P.E.) - An ether (otherwise known as di-iso-propyl ether), which is used in some fuel-ethanol plants as an entrainer in the dehydration process, as an alternative to benzene etc. It is a colorless, volatile liquid, chemical formula (CH3)2CHOCH(CH3)2, which boils at 67.5°C and freezes at -60°C. It readily forms explosive mixtures with air. Inhalation of vapors may cause narcosis and unconsciousness.

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Jet Cooker - An apparatus for the continuous cooking of grain mashes, in which the mash is pumped past a jet of steam which instantly heats the mash, to gelatinize the starch.

Jobber - Someone who purchases refined products at the wholesale level and then transfers or resells the product at the retail level. The retail level sale/transfer can occur at facilities owned by the jobber, independent dealers or commercial accounts.

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Karl Fischer Titration - A method to chemically determine the amount of water present in a sample of ethanol and/or other substances. When correctly practiced, the method can give an extremely accurate measurement of very small quantities of water in ethanol (in parts per million), even if gasoline denaturant is present. See Titration.

Kerosene -A light petroleum distillate that is used in space heaters, cook stoves, and water heaters and is suitable for use as a light source when burned in wick-fed lamps. Kerosene has a maximum distillation temperature of 400 degrees Fahrenheit at the 10-percent recovery point, a final boiling point of 572 degrees Fahrenheit, and a minimum flash point of 100 degrees Fahrenheit. Included are No. 1-K and No. 2-K, the two grades recognized by ASTM Specification D 3699 as well as all other grades of kerosene called range or stove oil, which have properties similar to those of No. 1 fuel oil. See Kerosene-Type Jet Fuel.

Kerosene-Type Jet Fuel - A kerosene-based product having a maximum distillation temperature of 400 degrees Fahrenheit at the 10-percent recovery point and a final maximum boiling point of 572 degrees Fahrenheit and meeting ASTM Specification D 1655 and Military Specifications MIL-T-5624P and MIL-T-83133D (Grades JP-5 and JP-8). It is used for commercial and military turbojet and turboprop aircraft engines.

   • Commercial - Kerosene-type jet fuel intended for use in commercial aircraft.

   • Military - Kerosene-type jet fuel intended for use in military aircraft.

Kluyveromyces fragilis (or marxianus) - A lactose-fermenting yeast used in the production of ethanol from cheese whey. Kubierschky Process - The first patented process for the continuous dehydration of ethanol with benzene. With relatively minor variations, the process developed in 1914 on the basis of Young's earlier batch process, is still used in many fuel-ethanol plants.

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Lactase - An enzyme that hydrolyzes lactose into glucose and galactose.  This hydrolysis allows lactose-containing feedstocks such as cheese whey to be fermented by the common Saccharomyces cerevisiae yeasts.  A principal source of lactase is the yeast Kluyveromyces fragilis, which can also directly ferment lactose to ethanol.

Lactobacillus - A genus (or class) of bacteria which produce lactic acid as a major product in the fermentation of carbohydrates. They are found extensively in fermenting food products, such as souring milk and in grain dust. They are the principal cause of loss of yield in ethanol fermentations. Otherwise referred to as lactic-acid bacteria, they are generally gram-positive and controllable with penicillin and certain other antibiotics.

Lag Phase - Applied to yeast propagation, refers to the initial period in which the yeast inoculum becomes adapted to the mash, prior to attaining the rapid increase in cell numbers referred to as the logarithmic phase.

Last Trading Day - The final trading session on a futures contact. Any contracts left open at the end must be settled by delivery. On the NYMEX, this falls on the last business day of the month for products and the third business day prior to the 25th on crude.

Less than Truckload (LTL) - A quantity of freight less than that required for the application of a truckload rate. Usually less than 10,000 pounds and generally involves the use of terminal facilities to peak and consolidate shipments.

LNG vehicle - A vehicle that uses LNG as its fuel.

Light-Duty Vehicle - Passenger cars and trucks with a gross vehicle weight rating of 8,500 or less.

Light Gas Oils - Liquid petroleum distillates heavier than naphtha, with an approximate boiling range from 401 degrees Fahrenheit to 650 degrees Fahrenheit.

Lignin - A polymeric, non-carbohydrate constituent of wood that functions as a support and plastic binder for cellulose fibers.  It may comprise 15-30% of wood and can only be separated from the cellulose and hemicellulose components by chemical reaction at high temperatures.  Its presence in wood is a major barrier to the hydrolysis of cellulose to sugars for fermentation purposes.

Lignocellulose - Woody materials made up largely of lignin, cellulose and hemicelluloses.  The chemical bonding between the constituents renders it resistant to hydrolysis.

Lime -A white alkaline powder composed of calcium oxide.  It is added to grain mash to adjust the pH and to provide calcium ions in order to prevent the inactivation of the a-amylase enzyme molecule by the loss of its essential calcium atom.

Liquefaction -The change in the phase, or conversion of a solid substance to the liquid state. In reference to starch, it is the stage in the cooking and saccharification process, in which gelatinized starch is partially hydrolyzed by an alpha amylase enzyme (or occasionally by an acid) to give soluble dextrins. This converts the starch mash into a free-flowing liquid.

Liquefied Natural Gas (LNG) - Compressed natural gas that is cryogenically stored in its liquid state.

Liquefied Petroleum Gas (LPG) A mixture of hydrocarbons found in natural gas and produced from crude oil, used principally as a feedstock for the chemical industry, home heating fuel, and motor vehicle fuel. Also known by the principal constituent propane.

Liter (L) - A metric measurement used to calculate the volume displacement of an engine. One liter is equal to 1,000 cubic centimeters or 61 cubic inches.

Limit Move - The maximum one-day price advance or decline permitted from the previous day’s settlement price. Not applicable to the current contract. The limit move is 2 cents on products and $1.00 on crude.

Limit Order - An order to buy/sell a futures/ options contract with a price limit. If it's a buy order, it can't be executed higher than the limit listed (e.g. 70cts gal). If it's a sell order, it can't be executed lower than the limit.

Locals - Term which describes the floor traders who provide liquidity for NYMEX traders; locals often are floor pokers who trade for their own account. Locals operate in the various pits of the NYMEX and typically trade large volumes and cash in profits or losses after small changes in price.

Logarithmic Phase - Applied to yeast propagation, refers to the period in which cell numbers are increasing at an exponential rate, after the initial lag phase.

Long - Having an outstanding position where one has bought a futures contract or a wet bbl. A speculative "long" would be hopeful of a market increase. A lot of "length" in the wet or futures market could be descriptive of a market where too many buyers are holding inventory.

Low Boilers - In reference to ethanol distillation, the term is applied to the congeners, or fermentation by-products, which boil at a lower temperature than ethanol.  More commonly referred to as heads, the compounds are principally aldehydes and methanol.

Low-Emission Vehicle (LEV) - A vehicle that meets EPA's CFV or LEV standards or CARB's California LEV standards.

LP - A shorthand reference commonly applied to propane, which is used as a home heating and cooking fuel, and as a petrochemical feedstock.

LPA -  Abpeviation for liters of pure alcohol.

Lupicants - Substances used to reduce friction between bearing surfaces or as process materials either incorporated into other materials used as processing aids in the manufacture of other products, or used as carriers of other materials. Petroleum lupicants may be produced either from distillates or residues. Lupicants include all grades of lupicating oils from spindle oil to cylinder oil and those used in greases.

Lupicity - Capacity to reduce friction.

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M100 - 100% (neat) methanol.

M85 - 85% methanol and 15% unleaded gasoline by volume, used as a motor fuel in FFVs.

Malt - Barley grains which have been steeped in water and then allowed to germinate. The germination is normally halted by drying the grains when the sprouts are about the same length as the grains. At this stage, the malt (or "malted barley") contains considerable amounts of alpha and beta amylase enzymes, which can saccharify the barley starch and other additional starch in a mash, to yield fermentable sugars. (In Scotland, the drying may be done by exposing the malt to a flow of peat smoke. This imparts a smokey odor to the malt.) Malt is used in whisky production, mainly for its contribution to product flavor, while in fuel-ethanol production the necessary saccharifying enzymes are normally derived from microbial sources.

Malt Whisky - In the U.S., it is defined by the B.A.T.F. as a whisky produced at less than 160° proof from a fermented mash containing at least 51 per cent malted barley, and stored at under 125° proof in charred, new, oak barrels. In Scotland, malt whiskies are made from a 100 per cent malted-barley mash, and may be aged in previously-used, oak barrels. Malt whiskies may be mixed with grain whiskies, to impart much of the characteristic flavor of blended Scotch whisky.

Margin - The funds deposited by a buyer or seller of a futures contract that ensure performance of the contract.

Margin Call - A demand for initial or variation margin from a commission house to a customer and/or from the clearing house to a clearing member.

Market on Close (MOC) - An order to buy/sell a futures/options contract which won't be executed until the close of trading that day. It will be executed at the best possible price within the closing minutes of the market.

Mash - A mixture of milled grain or other fermentable carbohydrate in water, which is used in the production of ethanol. The term may be used at any stage from the initial mixing of the feedstock in water, prior to any cooking and saccharification, through to the completion of fermentation, when it becomes referred to as "beer".

Meal - The floury or granular product resulting from milling or grinding of cereal grains.

Mechanical Vapor Recompression (M.V.R.) - A method used in evaporation in which the water vapor leaving the evaporator is recompressed and recycled to heat the same vessel.  This means of mechanical energy is used rather than heat energy.  The recompressor may be operated by electricity or by steam turbine (if high pressure steam is available and there is a demand elsewhere for the low pressure turbine exhaust steam).  Mechanical vapor recompression can greatly increase the steam usage efficiency, but the capital costs for equipment are also greater..

Medium-Duty Vehicle - Typically, a vehicle with a GVWR of 8,500 to 14,000 lb.

Merc - See NYMEX (New York Mercantile Exchange).

Merchant Oxygenate Plants - Oxygenate production facilities that are not associated with a petroleum refinery. Production from these facilities is sold under contract or on the spot market to refiners or other gasoline blenders.

Metals, High levels of Group I and II (in Biodiesel) - High levels of Group I and II metals. Sodium (Na), potassium (K), calcium (Ca), and magnesium (Mg) can cause deposits to form, catalyze undesired side reactions, and poison emission control equipment. The Group I and II metals are limited as the combination of metals in each category, Na+K and Ca+Mg. For each combination, the limit is 5 ppm.

Methane (CH4) - The simplest of the hydrocarbons and the principal constituent of natural gas. Pure methane has a heating value of 1,012 Btu per standard cubic foot.

Methane Digester (or Anaerobic Digester) - A system of covered tanks used for treatment of organic waste streams such as thin stillage.  The system is initially inoculated with a suitable culture of methane-producing bacteria and operates on a continuous basis to generate methane for use as a boiler fuel.

Methanol (also known as Methyl Alcohol, Wood Alcohol, CH3 OH) - A liquid fuel formed by catalytically combining CO with hydrogen in a 1 to 2 ratio under high temperature and pressure. Commercially, it is typically manufactured by steam reforming natural gas. Also formed in the destructive distillation of wood.  A colorless poisonous liquid, with essentially no odor and very little taste. It is the simplest alcohol, and has a formula CH3OH. It boils at 64.7°C. It is miscible with water and most organic liquids, including gasoline. It is extremely flammable, burning with a nearly invisible blue flame. It is a congeneric product of ethanol fermentations. Having a lower boiling point than ethanol, it tends to be a major component of the "heads" stream on distillation. Due to its miscibility with benzene, its presence in a hydrous ethanol feed may reduce the efficiency of dehydration processes where benzene is used as an entrainer. Methanol is produced commercially by the catalyzed reaction of hydrogen and carbon monoxide. It was formerly derived from the destructive distillation of wood, which caused it to be known as "wood alcohol". Methanol may be blended with gasoline, but requires a co-solvent such as ethanol or a higher alcohol to maintain it in solution. See Dupont Waiver. See Demethylizing Column.

Methyl Alcohol - See Methanol.

Methyl Ester - A fatty ester formed when organically derived oils are combined with methanol in the presence of a catalyst. Methyl Ester has characteristics similar to petroleum-based diesel motor fuels.

Methyl Tertiary Butyl Ether (MTBE) - A fuel oxygenate used as an additive to gasoline to increase octane and reduce engine knock. According to the U.S. Environmental Protection Agency, MTBE has been detected in ground water across the country, sometimes contaminating drinking water. Recent work by EPA and other researchers is expected to help determine the potential for health effects from MTBE in drinking water.

Metropolitan Statistical Area (MSA)/ Consolidated Metropolitan Statistical Area (CMSA) - According to the U.S. Census Bureau, an area qualifies for recognition as an MSA if it includes a city of at least 50,000 in population or an urbanized area of at least 50,000 with a total metropolitan area population of at least 100,000.Consolidated metropolitan statistical areas are defined similarly but have populations of 1 million or more and include within them separate metropolitan statistical areas. For purposes of EPAct, covered MSA and CMSA areas include those that had a 1980 U.S. Census population figure of more than 250,000.

Midco (Midcontinent) - A spot market designation for product delivered in Chicago.

Middle Distillates - A general classification of refined petroleum products that includes distillate fuel oil and kerosene.

Mobile Source Emissions - Emissions resulting from the operations of any type of motor vehicle.

Molasses - The thick liquid remaining after sucrose has been removed from the mother liquor (of clarified concentrated cane or beet juice), in sugar manufacture. Blackstrap molasses is the syrup from which no more sugar may be removed economically. It has usually been subjected to at least three evaporating and centrifuging cycles to remove the crystalline sucrose. Its analysis varies considerably, depending on many factors, including sugar-mill equipment and operational efficiency, but it may contain approximately 45 - 60 per cent by weight of fermentable sugars and approximately 10 per cent ash (or salts). It is commonly used as an ethanol feedstock when prices are favorable. High-test molasses (H.T.M.) is not a true molasses, as it is the mother liquor from which no crystalline sugar has been removed by centrifugation, but which has been treated with acid to reduce crystallization. It may contain approximately 80 per cent by weight of sugars, and is very low in ash. It is normally only produced in years when the sugar price does not justify its recovery. It may be used as an ethanol feedstock when prices are favorable, and has the advantage over blackstrap of causing less distillation-column scaling due to ash. However, it requires more nutrients for fermentation.

Molecular Sieve - A microporous substance composed of materials such as crystalline alumino-silicates, chemically similar to clays, and belonging to a class known as zeolites. The size of the pores in the substance may vary with its chemical structure, being generally in the range of 3 to 10 Ångstrom (Å) units in diameter. With material having a very precise pore size, it is possible to separate smaller molecules from larger ones, by a sieving action. For example, in ethanol dehydration with a potassium alumino-silicate material prepared with pores of a diameter of 3Å units, water molecules with a diameter of 2.5Å may be retained by adsorption within the pores, while ethanol molecules of a diameter of 4Å cannot enter, and therefore flow around the material.

The term "molecular sieve" is frequently used loosely to describe the entire ethanol-dehydration apparatus which holds the beads of sieve material and includes the equipment and controls necessary to regenerate them when saturated with water.

M.O.N. - Abpeviation for motor octane number.

Monosaccharide - A sugar monomer.  Examples are glucose, fructose and galactose.  These are the simplest forms of sugars, which are more readily fermented by yeasts than their polymers (or polysaccharides).

Mother Yeasting - A system of yeast propagation frequently used for molasses fermentations in which the propagator is not emptied entirely when inoculating a fermenter and the portion retained is used for starting another yeast propagation cycle.  By adding acid to maintain a low pH in the propagator it may be possible to repeat the process for numerous cycles without excessive bacterial contamination.

Motor-Fuel-Grade Ethanol (M.F.G.E.) - Refers to anhydrous ethanol prior to denaturation to fuel ethanol.  The term is used to distinguish it from the various grades of industrial and beverage ethanol.  MFGE is relatively crude, with considerable impurities, but conforms to legal anhydrous standards.  It has not undergone the rectification required to make it suitable for industrial or beverage uses.

Motor Gasoline Blending - Mechanical mixing of motor gasoline blending components, and oxygenates when required, to produce finished motor gasoline. Finished motor gasoline may be further mixed with other motor gasoline blending components or oxygenates, resulting in increased volumes of finished motor gasoline and/or changes in the formulation of finished motor gasoline (e.g., conventional motor gasoline mixed with MTBE to produce oxygenated motor gasoline).

Motor Gasoline Blending Components - Naphthas (e.g., straight-run gasoline, alkylate, reformate, benzene, toluene, xylenes) used for blending or compounding into finished motor gasoline. These components include reformulated gasoline blendstock for oxygenate blending (RBOB) but exclude oxygenates (alcohols, ethers), butane, and pentanes. Note: Oxygenates are reported as individual components and are included in the total for other hydrocarbons and oxygenates.

Motor Octane - The octane as tested in a single-cylinder octane test engine at more severe operating conditions. Motor octane number (MON) affects high-speed and part-throttle knock and performance under load, passing, climbing, and other operating conditions. Motor octane is represented by the designation M in the (R+M)/2 equation and is the lower of the two numbers.

Multiple-Effect Evaporator - A system comprising a series of interlinked evaporator vessels (or ‘effects’) operating under increasing degrees of vacuum.  As liquids boil at lower pressures with increasing vacuum, it is possible to use the latent heat of the vapors from one vessel to heat the next (and so on through a series of up to about six vessels under increasing vacuums) with steam or other external source of heat only being introduced to the first vessel.  This allows considerable economy in energy consumption.  Multiple effect evaporators are commonly used for concentrating thin stillage solids into syrups.

MVR - Abpeviation for mechanical vapor recompression.

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Naked Option - Sale of an option (either a put or a call) without ownership of the underlying futures contract.

Naphtha - A petroleum product off of the distillation process (220°F to 315°F) that is subsequently upgraded to make up the major constituent of gasoline.

National Biodiesel Board - A trade organization located in Jefferson City, MI consisting of producers and marketers of biodiesel.

Natural Gas - A naturally-occurring raw material often produced in conjunction with crude oil that is processed through a variety of facilities to yield NGLs. It is a commercially acceptable product for industrial and residential consumption and is shipped via pipeline.

Natural Gas Plant Liquids - Those hydrocarbons in natural gas that are separated as liquids at natural gas processing plants, fractionating and cycling plants, and, in some instances, field facilities. Lease condensate is excluded. Products obtained include ethane; liquefied petroleum gases (propane, butanes, propane-butane mixtures, ethane-propane mixtures); isopentane; and other small quantities of finished products, such as motor gasoline, special naphthas, jet fuel, kerosene, and distillate fuel oil.

Natural Gas Processing Plant - Facilities designed to recover natural gas liquids from a stream of natural gas that may or may not have passed through lease separators and/or field separation facilities. These facilities control the quality of the natural gas to be marketed. Cycling plants are classified as gas processing plants.

Natural Gasoline and Isopentane - A mixture of hydrocarbons, mostly pentanes and heavier, extracted from natural gas, that meets vapor pressure, end-point, and other specifications for natural gasoline set by the Gas Processors Association. Includes isopentane which is a saturated.

Near Neat Fuel - Fuel that is virtually free from admixture or dilution.

Neat Alcohol Fuel - Straight or 100% alcohol (not blended with gasoline), usually in the form of either ethanol or methanol.

Neat Fuel - Fuel that is free from admixture or dilution with other fuels.

Net Energy Balance - The amount of energy available from a fuel by combustion, less the amount of energy taken for its production.  In the early 1980s a lot of emphasis was placed on a need for net energy balance in the production of ethanol to be used as a gasoline extender.  The emphasis was later reduced when it became appreciated that a) much of the energy used in ethanol production may come from low quality sources such as coal, wood or bunker-C oil, which cannot be used as automobile fuels, and b) that ethanol has a value as an octane enhancer and oxygenate and not just a gasoline extender.

Neutral spirit - Defined by the B.A.T.F. as "distilled spirits produced from any material at or above 190° proof". In practice, neutral spirit is purified, odorless, tasteless and colorless ethanol, which has been produced by distillation and rectification techniques which remove any significant amount of congeners. It is used in the production of beverages such as vodka, gin, cordials, and cream liqueurs.

Net Profit Margin - A measure of profitability based on the ratio of net income to total operating revenues.

Netbacks -The price a refiner receives for the sale of petroleum products after deducting the transportation or affiliated costs in shipping the product from its point of origin (i.e., pipeline tariffs, waterborne freight, storage fees, line loss, cost of capital, etc.).

Netback Differential -The difference between the spot and rack prices for refined petroleum products.

Nomination - The notification by the seller of a spot market obligation of the attempt to deliver the product to satisfy the commitment.

Non-Attainment Area - A region, determined by population density in accordance with the U.S. Census Bureau, which exceeds minimum acceptable NAAQS for one or more "criteria pollutants" (see Clean Air Act Amendments). Such areas are required to seek modifications to their State Implementation Plans, setting forth a reasonable timetable using EPA-approved means to achieve attainment of NAAQS for these criteria pollutants by a certain date. Under the CAA, if a nonattainment area fails to attain NAAQS, EPA may superimpose a Federal Implementation Plan with stricter requirements or impose fines, constructions bans, cutoffs in federal grant revenues, and so forth, until the area achieves the applicable NAAQS.

Non-Methane Organic Gases (NMOG) - The sum of non-oxygenated and oxygenated hydrocarbons (exclusive of methane) contained in a gas sample as measured in accordance with California's non-methane organic gas test procedure.

Non-Regulated Trucking - A carrier which is exempt from economic regulation (e.g. exempt from agricultural shipments and private trucking operations).

Non-Road Vehicle (off-road vehicle) - A vehicle that does not travel streets, roads, or highways. Such vehicles include construction vehicles, locomotives, forklifts, tractors, golf carts, and others.

New York Mercantile Exchange (NYMEX) - Exchange where a number of commodities, including WTI crude, heating oil and unleaded gasoline are traded on a future basis.

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OEM - Original equipment manufacturer.

Octane - A measure of the performance quality of gasoline in terms of antiknock qualities. The higher the octane number, the greater the antiknock qualities.

Octane Enhancer - Any substance such as MTBE, ETBE, toluene, or xylene that is added to gasoline to increase octane and reduce engine knock.

Octane Rating (Octane Number) - A measure of a fuel's resistance to self-ignition, hence a measure as well of the antiknock properties of the fuel.

Off-Road - Any non-stationary device, powered by an internal combustion engine or motor, used primarily off the highways to propel, move, or draw persons or property, and used in any of the following applications: marine vessels, construction/farm equipment, locomotives, utility and lawn and garden equipment, off-road motorcycles, and off-highway vehicles.

Off-Road Diesel - Nothing more than high-sulfur No. 2 oil -- same as home heating oil. This fuel can be used for off-road purposes such as powering diesel construction equipment.

Office of Transportation and Air Quality - Division of EPA that protects public health and the environment by controlling air pollution from motor vehicles, engines, and the fuels used to operate them, and by encouraging travel choices that minimize emissions.

OIML Tables - The publication by the OIML in 1973 of the “International Alcoholometric Tables” (OIML R 22) was a decisive step which rapidly resulted in a complete international harmonization of national and regional alcoholometry systems: the symbol “% vol” (or any other equivalent symbol) may now be seen on practically all alcoholic beverage bottles that are produced all over the world. (Note:the OIML Tables refer to the IPTS68 temperature scale. Since 1990, a new IPT90 scale has been adopted by the Meter Convention; however, the differences between the two scales are relatively small and the figures in the 1975 OIML Tables - as well as those in any derived or practical table - are still valid). Based on these Tables the OIML has published a Recommendation on alcoholometers (R 44) and a compatible ISO International Standard also exists, referring to OIML Tables.

Oligosaccharide - Short-chain polymers of simple sugars (or monosaccharides), generally considered to cover the range of 2 to 8 units. Short dextrins produced by hydrolysis of starch are included in this category.

Onboard Refueling Vapor Recovery (ORVR) - System required on vehicles beginning in 1998 to control refueling emissions.

Organization of Petroleum Exporting Countries (OPEC) - Countries which have organized for the purpose of negotiating with oil companies on matters of oil production, prices and future concession rights. Current members are Algeria, Indonesia, Iran, Iraq, Kuwait, Libya, Nigeria, Qatar, Saudi Arabia, the United Arab Emirates and Venezuela. The Neutral Zone between Kuwait and Saudi Arabia is considered part of OPEC. Prior to January 1, 1993, Ecuador was a member of OPEC. Prior to January 1995, Gabon was a member of OPEC.

Open Interest - Figures published by the NYMEX which indicate the number of outstanding positions in a futures contract. An open interest number of 100,000 means that there are 50,000 long and 50,000 outstanding short positions. Rises or falls in open interest are often key barometers of whether a market is rising/falling thanks to new buying/selling or liquidation by existing participants. A rise in open interest after a market rally is often indicative of new buying, whereas a fall would have been representative of short covering.

Open-Loop Fuel Control - System in which the air/fuel mixture is preset by design with no feedback correction signal to optimize fuel metering.

Open Order - An order to buy or sell a futures contract or option which is good until it is cancelled. An order to buy crude at say $19 bbl, will be good until it's filled, with the pokerage house typically checking with clients at various intervals to see if there is interest in changing the order.

Opening - The period at the beginning of a trading session as designated by the exchange.

Open Outcry - A public auction form of futures trading where bids and offers are made directly between traders in an exchange pit.

Operable Capacity - The amount of capacity that, at the beginning of the period, is in operation; not in operation and not under active repair, but capable of being placed in operation within 30 days; or not in operation but under active repair that can be completed within 90 days. Operable capacity is the sum of the operating and idle capacity and is measured in barrels per calendar day or barrels per stream day.

Operable Utilization Rate - Represents the utilization of the atmospheric crude oil distillation units. The rate is calculated by dividing the gross input to these units by the operable refining capacity of the units.

Operating Capacity - The component of operable capacity that is in operation at the beginning of the period.

Operating Expenses - The costs of handling traffic, including both direct costs (driver wages and fuel) and indirect costs (computer expenses and advertising), but excluding interest expenses.

Operating Ratio - A measure of profitability based on operating expenses as a percentage of gross revenues.

Operating Utilization Rate - Represents the utilization of the atmospheric crude oil distillation units. The rate is calculated by dividing the gross input to these units by the operating refining capacity of the units.

Option - A contract traded on a futures exchange giving the buyer the right, but not the obligation, to buy (a call option) or sell (a put option) a specific quantity of a commodity from the seller or writer of the option.

Organoleptic Testing -The quality-control process of checking samples of alcoholic products on the basis of odor and taste. It is normally performed by comparing samples of new production with older samples of acceptable quality, which have been designated for use as "standards".

Original Equipment Manufacturer (OEM) - The original manufacturer of a vehicle or engine.

Other Oxygenates - Other aliphatic alcohols and aliphatic ethers intended for motor gasoline blending (e.g., isopropyl ether (IPE) or n-propanol).  Oxygenated Gasoline. See Motor Gasoline (Finished).

Out of the Money Option - Refers to an option where the futures price is less than the strike price for the appropriate call, or higher than the strike price for puts.

Over the Rack - Petroleum products sold at the wholesale level from primary storage. Refers to loading racks where tanker trucks fill up. Also Rack Market.

Overbought - A trading term used to express the opinion that prices have escalated rapidly, and therefore are subject to a sell-off as positions are liquidated.

Overhead Vapors - The vapors emerging from the top of a distillation column that are conducted to a condenser system.

Oversold - The opposite of overbought.

Oxidation stability - Biodiesel can oxidize during storage and handling, leading to the formation of peroxides, acids, gums, and deposits. The minimum oxidation stability requirement is intended to ensure the storage stability of B100 and biodiesel blends.

Oxides of Nitrogen (NOx) - Regulated air pollutants, primarily NO and NO2 but including other substances in minute concentrations. Under the high pressure and temperature conditions in an engine, nitrogen and oxygen atoms in the air react to form various NOx. Like hydrocarbons, NOx are precursors to the formation of smog. They also contribute to the formation of acid rain.

Oxygenate - A term used in the petroleum industry to denote fuel additives containing hydrogen, carbon, and oxygen in their molecular structure. Includes ethers such as MTBE and ETBE and alcohols such as ethanol and methanol.

Oxygenated Fuels - Fuels blended with an additive, usually methyl tertiary butyl ether (MTBE) or ethanol to increase oxygen content, allowing more thorough combustion for reduced carbon monoxide emissions.

Oxygenated Gasoline - Gasoline containing an oxygenate such as ethanol or MTBE. The increased oxygen content promotes more complete combustion, thereby reducing tailpipe emissions of CO.  Finished motor gasoline, other than reformulated gasoline, having an oxygen content of 2.7% or higher by weight.

Oxygenates - Substances which, when added to gasoline, increase the amount of oxygen in that gasoline blend. Fuel Ethanol, Methyl Tertiary Butyl Ether (MTBE), Ethyl Tertiary Butyl Ether (ETBE), and methanol are common oxygenates.

   • Fuel Ethanol: Blends of up to 10% by volume anhydrous ethanol (200 proof) (commonly referred to as the “gasohol waiver”).   

• Methanol: Blends of methanol and gasoline-grade tertiary butyl alcohol (GTBA) such that the total oxygen content does not exceed 3.5% by weight and the ratio of methanol to GTBA is less than or equal to 1. It is also specified that this blended fuel must meet ASTM volatility specifications (commonly referred to as the “ARCO” waiver). Blends of up to 5.0% by volume methanol with a minimum of 2.5% by volume cosolvent alcohols having a carbon number of 4 or less (i.e., ethanol, propanol, butanol, and/or GTBA). The total oxygen must not exceed 3.7% by weight, and the blend must meet ASTM volatility specifications as well as phase separation and alcohol purity specifications (commonly referred to as the “DuPont” waiver).

   • MTBE (Methyl tertiary butyl ether): Blends up to 15.0% by volume MTBE which must meet the ASTM D4814 specifications. Blenders must take precautions that the blends are not used as base gasolines for other oxygenated blends (commonly referred to as the “Sun” waiver).

Ozone - Tropospheric ozone (smog) is formed when volatile organic compounds (VOCs), oxygen, and NOx react in the presence of sunlight (not to be confused with stratospheric ozone, which is found in the upper atmosphere and protects the earth from the sun's ultraviolet rays). Though beneficial in the upper atmosphere, ground-level ozone is a respiratory irritant and considered a pollutant.

Ozone Transport Region (OTR) - The Clean Air Act Amendments of 1990 enable EPA to establish Ozone Transport Regions to reduce the likelihood ozone and its precursors will be carried from one area to another, lowering air quality in the downwind location. The first such region consists of Connecticut, Delaware, Maine, Maryland, Massachusetts, New Hampshire, New Jersey, New York, Pennsylvania, Rhode Island, Vermont, and the District of Columbia.

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P.A.D.D. - Abpeviation for Petroleum Administration for Defense District.

Palm oil - Palm oil is a form of edible vegetable oil obtained from the fruit of the oil palm tree. The palm oil and palm kernel oil are composed of fatty acids, esterified with glycerol just like any ordinary fat.

Paraffins - Group of saturated aliphatic hydrocarbons, including methane, ethane, propane, and butane and noted by the suffix "-ane".

Particulate Matter (PM) - A generic term for a poad class of chemically and physically diverse substances that exist as discrete particles (liquid droplets or solids) over a wide range of sizes. A NAAQS pollutant.

Particulate Trap - Diesel vehicle emission control device that traps and incinerates diesel particulate emissions after they are exhausted from the engine but before they are expelled into the atmosphere.

Penicillin - The collective name for salts of a series of antibiotic organic acids produced by a number of Penicillium and Aspergillus species molds, active against most gram-positive bacteria and some gram-negative cocci. (See Gram stain.) The commonest type of penicillin used in ethanol fermentations to control bacterial contamination is the potassium G form, otherwise known as benzyl penicillin potassium.

Pentanol - See amyl alcohol.

Permanganate (or Barbet) Time - A laboratory test used for assessing the quality of samples of industrial or beverage alcohol. It is the time required for an alcohol sample to decolorize a standard potassium permanganate solution. The time is an indication of the reducing (deoxidizing) power of the sample, and is considered to be a crude measure of the presence of congeners

Petroleum Administration For Defense Districts (PADD) -Five geographic area into which the United States was divided by the Petroleum Administration for Defense for purposes of administration during federal price controls or oil allocation. They are:

  • PADD1: Connecticut, Delaware, District of Columbia, Florida, Georgia, Maine, Maryland, Massachusetts, New Hampshire, New Jersey, New York, North Carolina, Pennsylvania, Rhode Island, South Carolina, Vermont, Virginia and West Virginia.
  • PADD2: Illinois, Indiana, Iowa, Kansas, Kentucky, Michigan, Minnesota, Missouri, Nepaska, North Dakota, Ohio, Oklahoma, South Dakota, Tennessee and Wisconsin.
  • PADD3: Alabama, Arkansas, Louisiana, Mississippi, New Mexico and Texas.
  • PADD4: Colorado, Idaho, Montana, Utah and Wyoming.
  • PADD5: Alaska, Arizona, California, Hawaii, Nevada, Oregon and Washington.

Petroleum Fuel - Gasoline or diesel fuel.

pH - A value measuring the acidity or alkalinity of an aqueous solution.  Defined as the logarithm of the reciprocal of the hydrogen ion concentration of a solution.  Pure water is used as the standard for arriving at pH because water molecules dissociate into H and OH ions with recombination at such a rate that at 22 Deg. C. there is a concentration of oppositely-charged ions of 1/10,000,000 or 10-7 mole per liter.  This is defined as a pH of 7.  Solutions with a pH of less than 7 are acidic, and greater than 7 are alkaline.  As the pH scale is logarithmic, a solution with a pH of 5 has 10 times the acidity of a solution of pH 6.  Control of pH in ethanol production both for obtaining optimal enzymatic activity and in controlling the growth of bacterial contaminants.

Phase Separation - The phenomenon of a separation of a liquid or vapor into two or more physically distinct and mechanically separable portions or layers.

Phosphorus content - This is limited to 10 ppm maximum in biodiesel because it can damage catalytic con­verters; phosphorus above 10 ppm can be present in some plant oils. Biodiesel produced in the United States generally has phosphorus levels of about 1 ppm

Pit Trading - Trading conducted within the normal hours of the NYMEX inside the open outcry pits. Pit hours are generally 9:45 a.m. to 3:10 p.m. Eastern time for most contracts. With the advent of overnight or after hours trading on the ACCESS automated system, it has become necessary to identify pit trading.

Plate (or Tray) - A contacting device placed horizontally at intervals within a distillation column. Plates may be simple perforated discs, with or without downcomers, as in the sieve plate and the dual-flow plate, or they may have bubble caps, tunnel caps, or various types of floating valves, to improve the contact between the rising vapor and descending liquid. Sieve plates and tunnel caps are the most common form of plates used in ethanol production facilities

Point - 1/100th of a cent ($0.0001).

Portable Fueling System - A system designed to deliver natural gas to fueling stations. Such systems are usually configured as tube trailers and are mobile. Fuel delivery usually occurs via over-the-road vehicles.

Position Limit - The maximum number of allowable open contracts for a single trader or a firm in a given futures contract.

Pot still - A simple batch distillation unit used for the production of heavily-flavored distillates for beverage use. It consists of a tank, (which is heated either by an internal steam coil, or by an external fire), and an overhead-vapor pipe leading to a condenser. It may be used in the production of heavily-flavored rums and whiskies.

Pounds Per Square Inch (psi) - A unit of measure for pressure.

Processing Gain - The volumetric amount by which total output is greater than input for a given period of time. This difference is due to the processing of crude oil into products which, in total, have a lower specific gravity than the crude oil processed.

Processing Loss - The volumetric amount by which total refinery output is less than input for a given period of time. This difference is due to the processing of crude oil into products which, in total, have a higher specific gravity than the crude oil processed.

Prompt Delivery (Prompts) - Designates a spot market delivery that must be made in the next few days as stipulated by the contract.

Product Transfer Order (PTO) - Pipeline authorizations transferring title to a set quantity of product at a specific location to another shipper.

Proof - A measure of the absolute-ethanol content of a distillate containing ethanol and water. In the U.S. system, each degree of proof is equal to 0.5 per cent of ethanol by volume, so that absolute ethanol is 200° proof. In the Imperial system "proof", (or 100° proof), is equal to 57.06 per cent ethanol by volume, or 48.24 per cent by weight, while absolute ethanol is 75.25 over proof, or 175.25° proof.

Proof Gallon - The volume of liquid that contains the equivalent of one gallon of ethanol at 100 Deg. Proof.

Propane (C3H8) - A gas whose molecules are composed of three carbon and eight hydrogen atoms. Propane is present in most natural gas in the United States, and is refined from crude petroleum. Propane contains about 2,500 Btu per standard cubic foot. Propane is the principal constituent in liquefied petroleum gas (LPG). It is a colorless paraffinic gas that boils at a temperature of -43.67 degrees Fahrenheit. It is extracted from natural gas or refinery gas streams. It includes all products designated in ASTM Specification D1835 and Gas Processors Association Specifications for commercial propane and HD-5 propane.

Propanol (or Propyl Alcohol) - A minor constituent of fusel oil. Chemical formula C3H7OH. It exists as either of two isomers. Both are colorless, toxic, flammable liquids, with odors similar to that of ethanol.

Pump Octane - The octane as posted on retail gasoline dispensers as (R+M)/2; same as Antiknock Index.

Put Option - Also referred to simply as a "put." Refers to an option which gives the buyer the right, but not the obligation, to sell a futures contract at a specified strike price.

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RBOB - Specially produced reformulated gasoline blendstock intended for blending with oxygenates downstream of the refinery where it was produced. Includes RBOB used to meet requirements of the Federal reformulated gasoline program and other blendstock intended for blending with oxygenates to produce finished gasoline that meets or exceeds emissions performance requirements of Federal reformulated gasoline (e.g. California RBOB and Arizona RBOB). Excludes conventional gasoline blendstocks for oxygenate blending (CBOB).

Rack Market - Petroleum products sold at the wholesale level from primary storage. Refers to loading racks where tanker trucks fill up.

Rapeseed - Rapeseed (passica napus), also known as Rape, Oilseed Rape, Rapa, Rapaseed and (one particular artificial variety) Canola, is a pight yellow flowering member of the family passicaceae (mustard or cabbage family).

Reboiler - A device for supplying heat to a distillation column without introducing live steam. It generally consists of a shell-and-tube heat exchanger connected to the base of the column, with liquid from the column entering inside the tubes, to be heated indirectly by steam on the shell side.

Rectification - The process of concentrating and purifying ethanol or other materials in a rectifying column.  The process may be operated simultaneously with beer distillation with the bee distillation with the rectifying column directly connected to a beer stripping column.  In beverage ethanol production the rectifying process may involve concentration and removal of fusel oil, esters and heads.  In fuel ethanol production the process commonly only involves concentration and the removal of fusel oil.  In some instances, where benzene is to be used as an entrainer in the subsequent dehydration process, the heads may also be removed in the rectification process.

Rectifying Column (rectifier, rectification column or rectifying section) - The portion of the distillation column above the feed tray in which rising vapor is enriched by interaction with a countercurrent descending stream of condensed vapor.  In the case of ethanol production, the rectifying column may have valves at draw-off points on various trays to allow the removal of accumulated fusel oil and other congeners.  In some instances the ethanol product is withdrawn from the reflux of the overhead vapor condensate, but in others the product may drawn from one of the upper trays to permit the heads or low boilers to be purged from the reflux.  (See Concentrating column).

Reflux - The portion of the condensed overhead vapors returned to a distillation column to maintain the liquid-vapor equilipium.

Reflux Ratio - The ratio of the amount of condensate being refluxed to the amount being withdrawn as product. Generally, the higher the reflux ratio, the greater is the degree of separation of the components in a distillation system.

Reformulated Gasoline (RFG) - Gasolines that have had their compositions or characteristics altered to reduce vehicular emissions of pollutants, particularly pursuant to EPA regulations under the CAA.

Refueling Emissions - VOC vapors that escape from the vehicle fuel tank during refueling. Storage II pump controls and onboard refueling vapor recovery systems (ORVR) are intended to control these emissions.

Regulated Motor Carrier - A carrier subject to economic regulation by the Department of Transportation.

Reid Vapor Pressure (RVP) - A standard measurement of a liquid's vapor pressure in psi at 100°F. It is an indication of the propensity of the liquid to evaporate.

Renewable Fuels Association (R.F.A.) - A Washington, DC based trade association for the US fuel ethanol industry.  Its membership includes companies involved in the production, blending and marketing of ethanol-blended fuels.

Research Octane Number (RON) - The octane as tested in a single-cylinder octane test engine operated under less severe operating conditions. RON affects low-to medium-speed knock and engine run-on. Research Octane is presented by the designation R in the (R+M)/2 equation and is the higher of the two numbers.

Residual Fuel Oil - A general classification for the heavier oils, known as No. 5 and No. 6 fuel oils, that remain after the distillate fuel oils and lighter hydrocarbons are distilled away in refinery operations. It conforms to ASTM Specifications D 396 and D 975 and Federal Specification VV-F-815C. No. 5, a residual fuel oil of medium viscosity, is also known as Navy Special and is defined in Military Specification MIL-F-859E, including Amendment 2 (NATO Symbol F-770). It is used in steam-powered vessels in government service and inshore power plants. No. 6 fuel oil includes Bunker C fuel oil and is used for the production of electric power, space heating, vessel bunkering, and various industrial purposes.

Resistance - A technical level where the current price of a commodity will have difficulty penetrating on a price trend.

Retrofit - To change a vehicle or engine after its original purchase, usually by adding equipment such as conversion systems.

Reverse Crack Spread - A spread trade implemented when a speculator thinks refiner margins will narrow. Products contracts are bought against crude contracts sold. See Crack Spread.

Reverse Osmosis (R.O.) - A technique used in water purification and wastewater and stillage treatment in which pressure is applied to the liquid in a suitable apparatus to force pure water through a mempane that does not allow the passage of dissolved ions.

Roller Mill - A mill for crushing or grinding grain or other solid material by passing it between two steel rollers. The rollers may be smooth, or serrated to shear the grain, and they may turn at differing speeds to increase the apasion. Roller mills are suitable for small grains such as wheat, but do not perform as well as a hammer mill on corn.

Round Turn - Both sides of a futures contract. When a commission is paid for a futures transaction, it is usually paid on a "round turn" basis where it covers both the purchase and sale.

Rotterdam - A port in the Netherlands. The most prevalent transaction point for spot market petroleum on the European continent. The second largest refining center in the world after Houston.

R.O.N. - Abpeviation for research octane number.

Rum - Defined by the B.A.T.F. as "an alcoholic distillate from the fermented juice of sugar cane, sugar-cane syrup, sugar-cane molasses, or other sugar-cane byproducts, produced at less than 190° proof, in such a manner that the distillate possesses the taste, aroma and characteristics generally attributed to rum." Unlike the specifications for whiskies, the B.A.T.F. does not require that the rum be aged in oak barrels. pitish regulations specify that rum be produced "from sugar-cane products in sugar-cane-growing countries."

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Saccharification - The process of converting a complex carbohydrate, such as starch or cellulose, into fermentable sugars such as glucose or maltose. It is essentially a hydrolysis. The process may be accomplished by the use of enzymes or acids.

Settlement/Settling Price - The price established by the Exchange Settlement Committee at the close of each trading session as the official price that will be used by the clearing house in determining net gains or losses on the day. The settlement or settling price provides the benchmark by which margin requirements and the next day's price limits are made. There are frequently significant variations between closing prices - those trades witnessed immediately before the closing bell, and the settlement prices.

Shochu - A distilled spirit made in Japan, using rice as the fermentation feedstock.

Shell Storage Capacity - The design capacity of a petroleum storage tank which is always greater than or equal to working storage capacity.

Short - Having an outstanding position to sell a wet bbl or a futures contract. A speculative "short" trader would be hopeful of a market decline so he could eventually buy back his bbl at a lower price. A market with too many short traders is often described as oversold.

Short Covering - Description which usually pertains to a market where speculative shorts are covering or cancelling out their positions by buying product. A rally from short covering is not indicative of new buying and is often violent but pief.

Sieve analysis - A laboratory test made on grain meal, to check that the milling process is being conducted correctly. The meal is added to the top of a stack of sieves with increasingly-finer meshes descending downwards. The sieve stack is vipated for a standard time period, and the weight percentage retained on each screen is determined. With hammermills, the sieve analysis will generally show that the meal gradually becomes coarser, as the hammers wear and need turning or replacement.

Singapore International Money Exchange (SIMEX) - A futures exchange in Singapore trading fuel oil.

Simultaneous Saccharification and Fermentation (S.S.F.) - A procedure in which the saccharification of a cooked starch mash occurs in the fermenter (by addition of enzymes), simultaneously with the commencement of fermentation (by addition of yeast). This procedure is replacing the traditional process taken from the whiskey industry, in which there is a specific holding stage for saccharification with malt or microbial enzymes (in a sacc' tank), prior to the mash going to a fermenter.

Slurry Tank - The vessel in which grain meal is mixed into a slurry with water before being pumped through a continuous cooking system.

Smog - A visible haze caused primarily by particulate matter and ozone. Ozone is formed by the reaction of hydrocarbons and NOx in the atmosphere.

Spark Ignition Engine - Internal combustion engine in which the charge is ignited electrically (e.g., with a spark plug).

Specialized Carrier - A trucking company franchised to transport articles which, because size, shape, weight, or other inherent characteristics, require special equipment for loading, unloading or transporting.

Specially-Denatured Alcohol (S.D.A.) - The term is used to describe ethanol denatured with any formulation of compounds selected from a list approved by the B.A.T.F. The denaturant renders the ethanol unfit for beverage purposes, without impairing its usefulness for other applications.

Speculator - Industry or non-industry participant who eyes a futures or options profit by anticipating a future price movement or changing relationship. A speculator might purchase 30 Dec. heating oil contracts at 50cts gal when he judges that technical or fundamental factors are likely to drive the prices higher.

Spot - A deal for supply wherein the price is negotiated between the buyer and the seller, and the supply commitment varies.

Spot Margin - Additional funds required to be on hand as a contract approaches its delivery date. When a NYMEX contract becomes the "spot" month (the first month on the board), margin requirements are increased automatically by the NYMEX. They increase again some five days prior to the last trading day, with the intent of encouraging players to move out of the delivery month.

Spot Market - High volume (25,000 to 300,000 bbls) contractual agreements between oil companies dictating delivery of petroleum products or crude oil in the near future for an established sales price. Since this market reacts quickly, and is an alternative to wholesale sales, it provides a good indication of the direction of wholesale price trends. Also referred to as Cash Market.

Spot Price - The current value of any product on a volume basis.

Spreads - In futures markets, applies to the difference between prices of futures contracts for different delivery months, or to the difference in prices for different commodities. Spread traders try to capitalize on likely fluctuations in these relationships, and initial spread margins are often considerably lower than for outright positions.

Squeeze - A trading situation where a lack of actual deliverable product exists. Traders who are short must buy back positions in a rapidly rising market.

S.S.F. - Abpeviation for simultaneous saccharification and fermentation.

Stakeholders - Citizens, environmentalists, businesses, and government representatives that are served by the air quality management system.

Standard Industrial Classification (SIC) Code - A classification of establishments by type of activity in which they are engaged: for the purpose of facilitating the collection, tabulation, presentation and analysis of data relating to establishments (e.g. SIC 421 Trucking & Courier Services, Except Air).

Starch - A mixture of two carbohydrate polymers (amylose and amylopectin), both of which are composed of glucose monomers linked together by glycosidic bonds. Starch is the principal energy-storage product of photosynthesis, and is found in most plants, particularly in roots, tubers and cereal grains. Starch may be subjected to hydrolysis (saccharification) to yield dextrins and glucose.

State Energy Program - Program offered by the U.S. Department of Energy that allows states to compete for funding to implement activities related to programmatic areas, such as federal energy management, building codes and standards, alternative fuels, industrial efficiency, building efficiency, and renewable energy technologies.

State Implementation Plan (SIP) - Plan that a state must submit to EPA under the CAA to demonstrate compliance to NAAQS.

Stillage - The mixture of non-fermentable (or non-fermented) solids and water, which is the residue after removal of ethanol from a fermented beer by distillation. Stillage may be dried to recover the solid material, (as D.D.G., in the case of grain feedstocks).

Stock Change - The difference between stocks at the beginning of the reporting period and stocks at the end of the reporting period. Note: A negative number indicates a decrease (i.e., a drawdown) in stocks and a positive number indicates an increase (i.e., a buildup) in stocks during the reporting period.

Stop Limit - A limit order to purchase (sell) above (or below in the case of a sell order) if a certain "stop price" is reached. Stop limit orders to buy or sell are often a key feature when critical technical levels are peached or surpassed in the market.

Stop Loss - A futures order designed to close out a losing position when the price reaches the specified level.

Stover - The dried stalks and leaves remaining from a crop, particularly corn, after the grain has been harvested.  It is of interest as a potential source of cellulose feedstock for ethanol production.

Straddle (Spread) - The purchase of one futures month against the sale of another futures month of the same commodity. A straddle trade is based on a price relationship between the two months.

Straight Truck - A vehicle with the cargo body and tractor mounted on the same chassis.

Strategic Petroleum Reserve (SPR) - Petroleum stocks maintained by the Federal Government for use during periods of major supply interruption.

Stripping Column (or Stripping Section) -The portion of a distillation column below the feed tray, in which the descending liquid is progressively depleted of its volatile components, by the introduction of heat at the base.

Sub Octane - Usually applies to a gasoline that does not meet the 87 octane standard which most suppliers mandate for regular unleaded distinction. Sub-octanes are typically utilized by those using oxygenated components.

Sugar - Any of a class of water-soluble, simpler-carbohydrate, crystalline compounds that vary widely in sweetness and include the monosaccharides and lower oligosaccharides. They may be chemically reducing or non-reducing compounds and are typically optically active. Examples include the monosaccharides, glucose, fructose, mannose and xylose, the disaccharides sucrose, maltose, lactose and the trisaccharides raffinose and maltotriose.

Sulfated ash test (in Biodiesel) - This test measures the amount of residual alkali catalyst in the biodiesel as well as any other ash-forming compounds that could contribute to injector deposits or fuel system fouling.

Sulfur - A yellowish nonmetallic element, sometimes known as “pimstone.” It is present at various levels of concentration in many fossil fuels whose combustion releases sulfur compounds that are considered harmful to the environment. Some of the most commonly used fossil fuels are categorized according to their sulfur content, with lower sulfur fuels usually selling at a higher price. This is limited to reduce sulfate and sulfuric acid pollutant emissions and to protect exhaust cata­lyst systems when they are deployed on diesel engines in the future. Note: No. 2 Distillate fuel is currently reported as having either a 0.05% or lower sulfur level for on-highway vehicle use or a greater than 0.05% sulfur level for off-highway use, home heating oil, and commercial and industrial uses. This also includes Ultra Low Sulfur Diesel (<15 ppm sulfur). Sulfur content of 15 ppm or lower is also required for proper functioning of diesel particle filters. Biodiesel generally contains less than 15 ppm sulfur. The test for low-sulfur fuel (ASTM D5453) should be used for accurate results instead of D2622, which will provide falsely high results caused by the test’s interference with the oxygen in the biodiesel.  Residual fuel, regardless of use, is classified as having either no more than 1% sulfur or greater than 1% sulfur. Coal is also classified as being low-sulfur at concentrations of 1% or less or high-sulfur at concentrations greater than 1%.

Sulfur Dioxide (SO2) - An EPA criteria pollutant

Super Ultra-Low-Emission Vehicle (SULEV) - A vehicle that produces fewer exhaust emissions than do ultra-low-emission vehicles. ULEV credits can also be banked in the Consolidated Metropolitan Statistical Area.

Support Area - A price level where a descending price movement is likely to encounter resistance.

Swap - An exchange of obligations to pay each other a defined amount based upon the relative values of a fixed price and specific index. Typically, one part receives a fixed price in exchange for an indexed (escalating) price. Settlement is in cash and at specified times. Example: If party A receives a fixed price and party B receives OPIS or Platts low, then party A collects the difference when OPIS or Platts is above the fixed price, and party B collects when it is lower.

Synthetic Ethanol - Ethanol produced by any one of several synthetic processes, such as the catalytic hydration of ethylene, the sulfuric-acid hydration of ethylene, and the Fischer-Tropsch process, in which it is a major byproduct of the synthesis of methanol by catalytically reacting carbon dioxide and hydrogen. Synthetic ethanol is chemically identical to fermentation ethanol, but does not qualify for U.S. federal or state incentives for blending with gasoline, and may not be used in the production of alcoholic beverages.

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T90 distillation specification - This specification was incorporated to ensure that fuels have not been contami­nated with high boiling materials such as used motor oil. B100 exhibits a boiling point rather than a distilla­tion curve. The fatty acids from which biodiesel are produced are mainly straight-chain HCs with 16 to 18 carbons that have similar boiling point temperatures. The atmospheric boiling point of biodiesel is generally 626º to 675ºF (330º to 357ºC).

TDP -  Abpeviated name for Thermal depolymerization.

Tails - See high boilers.

Tank Farm - An installation used by gathering and trunk pipeline companies, crude oil producers, and terminal operators (except refineries) to store crude oil.

Tanker and Barge - Vessels that transport crude oil or petroleum products. Data are reported for movements between PAD Districts; from a PAD District to the Panama Canal; or from the Panama Canal to a PAD District.

Tailpipe Emissions - EPA-regulated vehicle exhaust emissions released through the vehicle tailpipe. Tailpipe emissions do not include evaporative and refueling emissions, which are also regulated by EPA. EPA publishes allowable emission levels and vehicle certification standards in the Code of Federal Regulations.

Tax Incentives - In general, a means of employing the tax code to stimulate investment in or development of a socially desirable economic objective without direct expenditure from the budget of a given unit of government. Such incentives can take the form of tax exemptions or credits.

TBA (Tertiary butyl alcohol) (CH3)3COH - An alcohol primarily used as a chemical feedstock, a solvent or feedstock for isobutylene production for MTBE; produced as a co-product of propylene oxide production or by direct hydration of isobutylene.

Technical Analysis - Analysis primarily derived from studying historical buying/selling patterns in futures and spot markets and attempting to predict with reasonable certainty the probability of mimicking those movements again. Technical analysis is often very sophisticated and is probably the single most critical factor in determining day-to-day futures price movements.

Temporary Voluntary Allowance (TVA) - A discount given to a jobber, often when the supplier has a surplus and is likely to run down inventories, or when retail profit pressure requires temporary rack discounting.

Ternary Azeotrope - An azeotrope or constant-boiling mixture made up of three components. For example, a mixture of 74 per cent volume benzene, 18.5 per cent ethanol and 7.5 per cent of water forms an azeotrope boiling at 64.9°C.

Tertiary Amyl Ethyl Ether (TAEE) - An ether based on reactive C5 olefins and ethanol.

Tertiary Amyl Methyl Ether (TAME) - An ether based on reactive C5 olefins and methanol.

Tetraethyl Lead or Lead - An octane enhancer. One gram of lead increases the octane of one gallon of gasoline about 6 numbers. The EPA has phased down the use of lead in gasoline as it has been determined to be a health hazard. Lead has been prohibited in highway vehicle gasoline since January 1, 1996.

Therm - A unit of heating value equivalent to 100,000 pitish Thermal Units (Btu).

Thermal depolymerization (TDP) - Thermal depolymerization (TDP) is a process for the reduction of complex organic materials (usually waste products of various sorts, often known as biomass and plastic) into light crude oil. It mimics the natural geological processes thought to be involved in the production of fossil fuels. Under pressure and heat, long chain polymers of hydrogen, oxygen, and carbon decompose into short-chain petroleum hydrocarbons with a maximum length of around 18 carbons.

Thin Stillage - The liquid portion of stillage which has been separated from the solids by screening or centrifuging. It contains suspended fine particles and dissolved material. It is normally sent to an evaporator, to be concentrated to a thick syrup which is then dried with the solids portion to give D.D.G.S.

Time Value - The part of an options premium which reflects the excess over the intrinsic value, or which may reflect the entire premium if there is no intrinsic value. A call option for 60cts gal oil in a 58cts gal market that is trading at a premium of 2cts gal would represent a case where the entire premium is attributable to time value. Time value generally declines as an options contract nears expiration; it can represent the lion's share of the premium at great distances from expiration.

TOFC - Trailer on (rail) flat car. A form of piggyback movement of freight.

Toluene (C6H5CH3) - Colorless liquid of the aromatic group of petroleum hydrocarbons, made by the catalytic reforming of petroleum naphthas containing methyl cyclohexane. A high-octane gasoline-blending agent, solvent, and chemical intermediate, base for TNT.

Ton (Metric Ton) - The unit of measurement for crude or products outside of the United States. On average, there are seven barrels of crude per metric ton.

Ton-Mile - The movement of one ton of freight a distance of one mile. Ton-miles are computed by dividing the weight in tons of each shipment transported by the distance hauled.

Ton-Mile Tax - A tax calculated by measuring the weight of each truck for each trip. The gross weight is assigned a tax rate which is multiplied by the miles of travel.

Total sugars as invert (T.S.A.I.) - A simple crude analytical measure of reducing sugars in molasses.

Toxic Emission - Any pollutant emitted from a source that can negatively affect human health or the environment.

Toxic Substance - A generic term referring to a harmful substance or group of substances. Typically, these substances are especially harmful to health, such as those considered under EPA's hazardous substance program. Technically, any compound that has the potential to produce adverse health effects is considered a toxic substance.

Traders - Buyers and sellers of large quantities of petroleum products. They use the spot markets as a basis for their deals.

Transesterification - Transesterification is the process of exchanging the alkoxy group of an ester compound by another alcohol. These reactions are often catalyzed by the addition of an acid or base. Acids can catalyse the reaction by donating a proton to the carbonyl group, thus making it more reactive, while bases can catalyse the reaction by removing a proton from the alcohol, thus making it more reactive. The name "biodiesel" has been given to transesterified vegetable oil to describe its use as a diesel fuel. The transesterification process involves mixing at room temperature methanol (50% excess) with NaOH (100% excess), then mixing vigorously with vegetable oil and letting the glycerol settle (about 15% of the biodiesel mix). The supernatant is biodiesel and contains a mixture of methylated fatty acids and methanol.  

Transitional Low-Emission Vehicle (TLEV) - Describes a vehicle that meets either EPA's CFV TLEV standards or CARB's California Low-Emission Vehicle Program TLEV standards. TLEVs produce fewer emissions than federal Tier 1 vehicles. TLEVs are eligible for the federal California Pilot Program but not eligible for the Clean-Fuel Fleet Program.

Trigger Deals - Futures-related or derivative instrument which allows a marketer to lock into a price relationship, but gives him the opportunity to set the absolute price at a later date. A supplier might sell a trigger deal to a heating oil marketer whereby the marketer is guaranteed product at 2cts gal over the Dec. futures price for No. 2 oil. The marketer has until an agreed upon date to "pull the trigger" to set the absolute value of the transaction.

Truck - A motor vehicle designed to carry an entire load. It may consist of a chassis and body; a chassis, cab and body; or it may be of integral construction so that the body and chassis form a single unit.

Truck Tonnage - The weight of freight in tons transported by truck.

Truckload (TL) - Quantity of freight required to fill a truck. When used in connection with freight rates, the quantity of freight necessary to qualify a shipment for a truckload rate. Usually in excess of 10,000 pounds.

Turnaround - Originally, this term applied to the periodic inspection and maintenance of an oil refinery. It now applies to any shutdown, slowdown or operational problem pought upon by refinery maintenance. Turnarounds are then said to be "planned" or "unplanned."

Turnpike Double - A combination vehicle consisting of a tractor and two trailers of 33 to 48 feet.

Twin Trailer - A short semitrailer (under 29 feet) designed to be operated as part of a combination vehicle with a tandem trailer of similar length.

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Ultrafiltration - A process for the separation of colloidal or very fine solid materials, or large dissolved molecules, by filtration through microporous or semi-permeable mempanes. The process may be used for removal of protein from cheese whey prior to fermentation.

U.S. Department of Agriculture (USDA) - A government agency whose mission is to improve and maintain farm income, to develop and expand markets for agricultural products, etc. Through such agencies as the Farm Home Administration (FmHA) and the Commodity Credit Corporation (CCC) the USDA has been involved in assisting the development of the fuel ethanol industry.

U.S. Department of Energy (DOE) - A department of the federal government, established by the Carter Administration in 1977, to consolidate energy-oriented programs and agencies. The DOE mission includes the coordination and management of energy conservation, supply, information dissemination, regulation, research, development and demonstration.

U.S. Department of Transportation - A government agency whose mission is to ensure a fast, safe, efficient, accessible, and convenient transportation system that meets the national interests and enhances our quality of life.

U.S. Environmental Protection Agency (EPA) - A government agency, established in 1970, responsible for protecting the environment and public health. EPA seeks to reduce air, water, and land pollution and pollution from solid waste, radiation, pesticides, and toxic substances. EPA also controls emissions from motor vehicles, fuels, and fuel additives.

U.S. Gallon - A measure of 231 cubic inches liquid at 60°F. It is the equivalent of 3.785 liters, in the metric system, or 5/6 of an Imperial gallon.

Ultra-Low-Emission Vehicle (ULEV) - Describes a vehicle that meets either EPA's CFV ULEV standards or CARB's California Low-Emission Vehicle Program ULEV standards. ULEVs produce fewer emissions than LEVs. Fleets that purchase CFV ULEVs may earn credits under the Clean-Fuel Fleet Vehicle Program. Manufacturers that sell CFV ULEVs may earn credits under the federal California Pilot Program.

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Vacuum Fermentation - A process of operating a fermentation under vacuum, so that the ethanol or other product is vaporized and removed as it is formed, to avoid its concentration becoming inhibitory to the yeast. In a patented variation known as the "Vacuferm" process, instead of maintaining the entire fermenter under vacuum, the fermenting beer is circulated through a vacuum chamber to flash off the ethanol, before returning the beer to the fermenter.

Vapor Pressure or Volatility - The tendency of a liquid to pass into the vapor state at a given temperature. With automotive fuels, volatility is determined by measuring RVP.

Variable Fuel Vehicle (VFV) - A vehicle that has the capacity of burning any combination of gasoline and an alternative fuel. Also known as a flexible-fuel vehicle.

Variation Margin - The unrealized loss in a position. Traders must post these funds to ensure that their initial margin is restored to its starting balance.

Vehicle Conversion - Retrofitting a vehicle engine to run on an alternative fuel.

Vehicle Miles Traveled - The miles traveled by motor vehicles over a specified length of time (e.g. daily, monthly, or yearly) or over a specified road or transportation corridor.

Viscosity (in Biodiesel) - A minimum viscosity is required for some engines because of the potential for power loss caused by injection pump and injector leakage. This is not an issue for B100, and the minimum is set at the same level as for petroleum diesel. The maximum viscosity is limited by the design of engine fuel injection systems. Higher viscosity fuels can cause poor fuel combustion that leads to deposit formation as well as higher in-cylinder penetration of the fuel spray, which can result in elevated engine oil dilution with fuel. The maximum allowable viscosity in ASTM D975 for No. 2 diesel is 4.1 mm2/s at 104ºF (40ºC). ASTM D6751 allows for slightly higher viscosity than D975, primarily because that is where the normal viscosity of B100 lies. Biodiesel blends of 20 vol % or lower should have a viscosity within the range allowed by D975.

Vinasse - The term sometimes applied to the stillage of molasses, grape juice, or other liquid ethanol feedstocks.

Volatile Organic Compound (VOC) - Reactive gas released during combustion or evaporation of fuel and regulated by EPA. VOCs react with NOx in the presence of sunlight and form ozone.

Volatility - The tendency of a solid or liquid to pass into the vapor state at a given temperature. With automotive fuels, the volatility is determined by measuring the Reid vapor pressure (R.v.p.).

Volume - The number of transactions made on a futures exchange that would consist of a purchase and a matching sale.

Voluntary Mobile Source Emission Reduction Program - A program established by EPA to encourage voluntary emission reduction programs that can be part of a state implementation program.

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Water and sediment (in Biodiesel) - This refers to free water droplets and sediment particles. The allowable level for B100 is set at the same level allowed for conventional diesel fuel. Poor drying techniques during manufacturing or contact with excessive water during transport or storage can cause B100 to be out of specification for water content. Excess water can lead to corrosion and provides an environment for microorganisms. Fuel oxida­tion can also raise sediment levels, so this test can be used in conjunction with acid number and viscosity to determine if fuels have oxidized too much during storage.

Weeping - The condition when droplets of liquid fall through the holes of a sieve plate in a distillation column. It may be caused by (a) having a steam flow that is too low, or (b) having too low a liquid flow to maintain a level on the plate, or (c) having a tilted plate, so that the liquid depth is uneven.

Wet Barrel - Industry term to specify actual physical barrels, often in a very prompt timeframe. Contrasts with paper bbl, where title is not backed up with actual physical material.

Wet Milling – A process in which corn is first steeped (or soaked) in water containing sulfur dioxide.  This softens the kernels and loosens the hulls.  (The liquid when separated is known as corn steep liquor.)  The grain is then degermed by apasion and liquid separation.  Oil is extracted from the germ, while the remainder of the kernel is ground in impact fiber mills and passed through stationary screens to separate the starch and gluten from the fiberous portion.  The heavier starch is then separated from the gluten by use of centrifuges.  The starch portion may then be processed into commercial starch, or it may be used as a feedstock for production of ethanol or HFCS.

Whole Stillage – The entire stillage emerging from a distillation unit before any removal of solids by screening or centrifuging.

Wine Gallon - A U.S. gallon of liquid measure, as distinct from a proof gallon.

Wood Alcohol - See Methanol.

Working Storage Capacity - The difference in volume between the maximum safe fill capacity and the quantity below which pump suction is ineffective (bottoms).

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Xylenes (C6H4(CH3)2) - Colorless liquid of the aromatic group of hydrocarbons made the catalytic reforming of certain naphthenic petroleum fractions. Used as high-octane motor and aviation gasoline blending agents, solvents, chemical intermediates. Isomers are metaxylene, orthoxylene, paraxylene. 

Xylose - A pentose (or 5-carbon sugar), derived from the hydrolysis of hemicellulose. Chemical formula C5H10O5. It is not fermented by normal strains of distillers yeasts.

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Yeast – Any of certain unicellular fungi, generally members of the class Ascomycetaceae ( a few are members of the class Basidiomycetaceae).  Many yeasts are capable of producing ethanol and carbon dioxide by the anaerobic fermentation of sugars.  Yeasts are composed of approximately 50% protein and are a rich nutritional source of B vitamins.

Yeast autolysis – The disintegration of yeast cells by action of their own enzymes.

Yeast cream – Yeast concentrated by centrifuging or decanting from the contents of a propagator or fermenter to be used as inoculum in another fermenter.

Yeast propagator (or prefermenter) – A tank used for the propagation or development of yeast culture prior to transfer to a fermenter.  It is normally fitted with aeration, agitation and cooling devises and is designed for ease of cleaning and sterilization.

Yeast strain – A pure culture of yeast derived from a single isolation.  Strains may be specially selected for certain characteristics such as the ability to efficiently produce and tolerate high levels of ethanol.

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Zeolite -  See Molecular sieve.

Zero Emission Vehicle (ZEV) -  A vehicle that emits no tailpipe exhaust emissions. ZEV credits can be banked within the Consolidated Metropolitan Statistical Area.

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