Glossary

Abbreviation for one thousand cubic meters.

The process of removing vapors from a stream of natural gas by passing the natural gas through liquids or chemicals which have a natural attraction to the vapors to be removed from the stream.

The hydrogen sulfide (H2S) and/or carbon dioxide (CO2) contained in or extracted from natural gas or other streams.

The process of removing natural gas liquids from a stream of natural gas by passing the natural gas through granular solids which have a natural attraction to the liquids to be removed from the stream.

The process of apportioning the total volume (or value) of produced hydrocarbons to the wells that flow through a gathering system or to a common delivery point (CDP).

A Hydrocarbon density scale, beginning at 7 (the densest) and running through 52 (the lease dense). It is an inverse measure of a petroleum liquid’s density relative to that of water (also known as specific gravity).

Natural gas from an oil well. Also called casinghead gas.

Refining process that szeparates light hydrocarbons from crude oi.

The pressure exerted on the earth by the earthÕs atmosphere.Ê A pressure of 760 mm of mercury, 29.92 inches of mercury, or 14.696 psia is used as a standard for some measurements.Ê The various state regulatory bodies have set other standards for use in measuring the legal volume of natural gas that is sold or processed.Ê Atmospheric pressure may also refer to the absolute ambient pressure at any given location.

A unit of liquid volume measurement in the petroleum industry that equals 42 U.S. gallons for petroleum or natural gas liquid products, measured at 60 degrees Fahrenheit and at an equilibrium vapor pressure.

Abbreviation for barrel.

One billion standard cubic feet or one thousand MMcf or one million Mcf.

A liquefied hydrocarbon product composed primarily of butanes and natural gasoline.

Barrel of Oil Equivalent — the amount of energy produced by gas equated to oil; generally held to be 1:6.

The an ideal gas law where at constant temperature, the volume of an ideal gas is inversely proportional to its absolute pressure..

A liquefied hydrocarbon product composed primarily of butanes and propane.

Base sediment and water; the sediment and water that accumulates at the bottom of an oil tank.

Abbreviation for British Thermal Unit which is the amount of heat necessary to raise one (1) pound of pure water from fifty-nine (59) degrees Fahrenheit to sixty (60) degrees Fahrenheit at a specified constant pressure.

A numerical representation of the heating value of natural gas which may be calculated or presented to indicate varying relationships (e.g., the number of Btu contained in one standard cubic foot or the number of MMBtu contained in one Mcf of gas.Ê The factor for a given relationship will vary depending upon whether the gas is ÒdryÓ or ÒsaturatedÓ.

The pressure at which gas will begin to form into a liquid at a given temperature.

A normally gaseous paraffin compound having the chemical formula of C4H10.

see Normal Butane.

A standard abbreviation for Methane.

A standard abbreviation for Ethane.

A standard abbreviation for Propane.

A standard abbreviation for Pentanes Plus (IC5, NC5 and C6+).

A standard abbreviation for Hexane Plus.

An apparatus that is used to empirically determine the heating value of a combustible material.

A heavy colorless gas having the chemical formula of CO2, which is commonly referred to as dry ice when in its solid form.

Natural gas that is produced from oil wells along with crude oil.

A standard abbreviation for Cubic foot.

An analytical instrument that separates mixtures of substances into identifiable components by means of chromatogophry.

A technique for separating a mixture into individual components by repeated adsorption and desorption on a confined solid bed used for analysis of natural gas and natural gas liquids.

Compressed Natureal Gas

A standard abbreviation for Carbon Dioxide.

Production of hydrocarbons from multiple producing wells, zones or horizons into a single tank or meter that must be allocated to different owners due to differing ownership.

A factor usually expressed as ÒzÓ which gives the ratio of the actual volume of gas at a given temperature and pressure to the volume of gas when calculated by the ideal gas law without any consideration of the compressibility factor.

The liquid formed by the condensation of a vapor or gas; specifically, the hydrocarbon liquid separated from natural gas because of changes in temperature and pressure when the gas from the reservoir was delivered to the surface separators.Ê Condensate remains a liquid at atmospheric temperature and pressure.

A gas processing plant which is capable of producing natural gas liquids products, including ethane, at very low operating temperatures.

The terminal in Oklahoma at which crude oil prices are quoted.

The unit of heat energy equivalent to one million British thermal units (BTU), or an MMBTU.

The temperature at any given pressure at which liquid initially condenses from a gas or vapor.Ê It is specifically applied to the temperature at which water vapor starts to condense from a gas mixture (water dew point) or at which hydrocarbons start to condense (hydrocarbon dew point).

Abbreviation for Decatherm, equivalent to one MMBtu.

Hydrocarbon liquid that separates in a pipeline transporting gas from the well casing, lease separation, or other facilities and drains into equipment from which the liquid can be removed.

The heating value of a cubic foot of natural gas that does not contain a significant moisture (water) content.

Natural gas that either (1) does not contain a significant moisture (water) content, or (2) does not contain significant amounts of liquefiable hydrocarbons.Ê Gas in this second definition preferably should be called lean gas.

A liquefiable hydrocarbon product consisting primarily of ethane and propane.

A normally gaseous paraffin compound having the chemical formula of C2H6.

The initial party to purchase crude oil or natural gas from a producer. Ultimately responsible for taxes and revenue / royalty distribution.

Gas vapors released from a stream of natural gas liquids as a result of an increase in temperature or a decrease in pressure.

The process of separating a steam of natural gas liquids into its separate components.

A standard abbreviation for Cubic Foot.

An abbreviation for one gallon.

A facility that takes natural gas, removes impurities and separates the hydrocarbons into their various components.

The separation of components by absorption, adsorption, refrigeration or cryogenics from a stream of natural gas for the purpose of making salable liquid products and for treating the residue gas to meet required specifications.

Measure of the volume of gas produced along with oil from the same well.

Pipelines that collect gas and oil from more than one location and deliver it to a central facility or delivery point.

An abbreviation for gigajoule, equivalent to one thousand megajoules or one billion joules.

Gallons per Mcf, the number of gallons of a particular component per Mcf.

The heating value measured in a calorimeter when the water produced during the combustion process is condensed to a liquid state.Ê The heat of condensation of the water is included in the total measured heat.

A standard abbreviation for Hydrogen Sulfide.

The amount of heat developed by the complete combustion of a unit quantity of a material.Ê Heating values for natural gas are usually expressed as the Btu per Cf of gas at designated conditions (temperature and pressure) and either on the dry or water saturated basis.

The portion of a hydrocarbon mixture having the highest boiling point.Ê Hexanes or heptanes and all heavier hydrocarbons are usually the heavy ends in a natural gas stream.

A terminal in Loiusiana at which natrual gas prices are quoted.

The portion of a hydrocarbon fluid mixture or the last component of a hydrocarbon analysis which contains the hexanes (or heptanes) and all hydrocarbons heavier than the hexanes (or heptanes).

See Gross Heating Value.

Organic compounds including oil and gas.

A flammable, very poisonous and corrosive gas with a markedly disagreeable odor, having the chemical formula of H2S that is a contaminant in natural gas and natural gas liquids.

A standard abbreviation for Isobutane.

A standard abbreviation for Isopentane.

Elements or compounds not acted upon chemically by the surrounding environment.Ê Nitrogen and carbon dioxide are examples of inert components in natural gas.Ê Inerts dilute the natural gas and since they do not burn or combust, have no heating value.

A hydrocarbon of the paraffin series having a chemical formula of C4H10 and having its carbon atoms branched.

A hydrocarbon of the paraffin series having a chemical formula of C5H12 and having its carbon atoms branched.

The International System unit of electrical, mechanical, and thermal energy.Ê A unit of electrical energy equal to the work done when a current of 1 ampere is passed through a resistance of 1 ohm for 1 second.Ê A unit of energy equal to the work done when a force of 1 newton acts through a distance of 1 meter.

The portion of a liquid hydrocarbon mixture having the lowest boiling points which are easily evaporated.

The low molecular weight hydrocarbons such as methane, ethane, propane and butanes.

The components of natural gas that may be recovered as liquid products.

The light hydrocarbon portion of natural gas that is predominantly methane and which has been liquefied.

Predominantly propane or butane separately or in mixtures that are maintained in a liquid state under the pressure within the confining vessel.

Abbreviation for Liquefied Natural Gas.

See Net Heating Value.

Abbreviation for Liquefied Petroleum Gas.

Abbreviation for one thousand cubic feet.Ê A standard unit for measuring or expressing the volume of a thousand cubic feet of gas for which the pressure and temperature conditions for the standard measurement must be defined.

The first member of the aliphatic hydrocarbon series having the chemical formula of CH4.Ê Natural gas is primarily composed of Methane.

That part of the energy industry engaged in the gathering, processing, marketing and transportation of hydrocarbons.

Abbreviation for megajoule, equivalent to one million joules.

One million Btus.

One million standard cubic feet or one thousand Mcf.

The number of molecules of an inert or hydrocarbon component contained in a sample of natural gas, or natural gas liquid, expressed as a percentage of the total molecules in the sample.

A standard abbreviation for Nitrogen.

Natural gas liquids are those hydrocarbons liquefied at the surface in field facilities or in gas processing plants and include propane, butane and natural gasoline.

A mixture of hydrocarbons, mostly pentanes and heavier, extracted from natural gas, which meets vapor pressure and other specifications.

A standard abbreviation for Normal Butane.

A standard abbreviation for Normal Pentane.

The heating value measured in a calorimeter when the water produced during the combustion process is not condensed.

A standard abbreviation for Natural Gas Liquids.

The process of placing a bid to a pipeline to deliver or take a certain amount of natural gas for a specific period.

An aliphatic compound of the paraffin series having the chemical formula of C4H10 and having all of its carbon atoms joined in a straight chain.

A hydrocarbon of the paraffin series having a chemical formula of C5H12 and having all its carbon atoms joined in a straight chain.

A standard abbreviation for oxygen.

A type of meter used to measure gas where the gas passes through an orfice plate, and the differential pressure is used to calculate the amount of gas flow.

Abbreviation for Pounds per Square Inch Absolute.Ê Absolute pressure is the sum of Atmospheric Pressure plus Gauge Pressure.

See Normal Pentane.

A hydrocarbon mixture consisting mostly of normal pentane and heavier components.

The process of matching a gas nomination with actual flow. The goal is to avoid pipeline pentalties for under or over producing by borrowing or purchasing gas from or lending or selling gas to other producers or gatherers.

Liquid hydrocarbons that have condensed from gas to liquid as a result of changes in pressure and temperature as gas flows in a pipeline.Ê Pipeline condensate only remains as a liquid under high-pressure conditions and would vaporize at atmospheric pressure.

The amount or inventory of hydrocarbons in a pipeline between the receipt and delivery points in a gathering system. Also called Line Fill.

The tool inserted into a pipeline that travels the length of the pipeline pushed by hydrocarbon flow, used to remove liquids or other objects which could obstruct flow.

All liquid hydrocarbons and other products (including sulfur and excluding residue gas) recovered in a gas processing plant.

The contractual, regulatory or standard ambient pressure at which natural gas is measured or sampled expressed in psia (pounds per square inch absolute).

Paying a gas royalty owner based on actual production or entitlement and reconciling and settling the delta.

A normally gaseous paraffin compound having the chemical formula of C3H8.

Natural gas that has not been processed.

A mixture of natural gas liquids that has not been fractionated or separated into its various components.

The portion of natural gas remaining in a gaseous state after recovery of certain components through gas processing.

Natural gas which, based on its content of liquefiable hydrocarbons, is suitable for processing in a gas plant for recovery of plant products.

The heating value of natural gas that is saturated with water vapor.

Supervisory Control and Data Access – a technique to remotely monitor and control a well.

Abbreviation for one standard cubic foot, a measurement of a gas volume at a contractual, regulatory or standard specified temperature and pressure.

The reduction in volume and/or heating value of a natural gas stream due to extraction or removal of some of its components.

Natural gas that has a high concentration of H2S.

A pale, yellow, non-metallic chemical element that may be found in a gas stream and which needs to be removed or reduced from the gas stream for corrosion control or health or safety reasons.

Crude oil having a sulfur content less than 0.5 percent (by weight).

The right of a producer or royalty owner to take physical possession of their share of oil or gas and sell it for their own account.

A gas contract in which a purchaser must pay even if they don’t fulfill the volumetric requirement of the contract.

Trillion Cubic Feet

The content of liquefiable hydrocarbons in a volume of natural gas determined from tests or analyses of the gas.

The part of the energy industry concerned with the finding and extraction of oil and gas.

A hydrocarbon of the paraffin series having a chemical formula of C5H12 and having all its carbon atoms joined in a straight chain.

Natural gas that contains either (1) a significant amount of liquefiable hydrocarbons, or (2) a significant amount of moisture (water).