Definitions of words and terms used in the gas processing industry.
For questions regarding incorrect/outdated entries or suggestion for adding additional terms, please contact Martin Erne
A number that represents the ratio of gas molar fraction to liquid molar fraction.
Refer to the definition of "vapor-liquid equilibrium ratio."
An arbitrary scale expressing the relative density of liquid petroleum products. The scale is calibrated in degrees API, calculated by the following formula: (141.5 / relative density) -131.5
When the API Gravity is greater than 10, the petroleum liquid is lighter than and floats on water; if less than 10, it is heavier than and sinks in water.
Any distillation made in accordance with an ASTM procedure. Generally, it refers to a distillation test to determine the initial boiling point, the temperature at which percentage fractionations of the sample are distilled, the final boiling point, and the quantity of residue. (For example, see ASTM method D-86.)
The results calculated from the ASTM distillation are used in subsequent calculations.
A national trade association of the petroleum industry whose members are U.S. and Canadian distributors of natural, manufactured, and mixed gases. AGA provides information on sales, finances, utilization, and all phases of gas transmission and distribution.
AGA technical standards are referenced in the contract for natural gas custody transfer and related activities.
A national trade association of the petroleum industry which is a standardizing organization for the drilling, producing, refining, transportation, and marketing segments of the industry.
API technical standards are referenced in many contracts as well as state and federal regulations.
An international organization which promotes knowledge of the materials of engineering and the standardization of specifications and methods of testing.
ASTM International test procedures are cited in many product specifications.
A liquified hydrocarbon product composed chiefly of butanes and propane.
B-P mixes that originate from a refinery, commonly contain olefins. The B-P mix commonly conforms to the specifications as defined in GPA Midstream Publication 2140.
A thin-walled flattened tube of elastic metal bent into a circular arc whose application to certain pressure gauges and thermometers depends upon the fact that increase of pressure inside the tube tends to straighten it.
The analog gauge used a Bourdon tube for pressure measurement.
A thermodynamic law which states that for an ideal gas or mixture of ideal gases at a constant temperature, the product of the absolute pressure times the volume is a constant, i.e., PV = K.
Boyle’s Law could be used at low pressure when gas is nearly ideal.
An acronym for “British thermal unit”. A measure of the quantity of energy transferred as thermal energy.
One Btu is equal to the amount of heat required to raise the temperature of one pound of water by one degree Fahrenheit.
A device that elevates gas pressure by adding kinetic energy/velocity to the gas as it flows through an impeller.
Centrifugal compressors are used in pipeline booster service where high volume and low compression ratios exist.
Half of the ideal gas law equation stating that at constant pressure the volume of a given mass of an ideal gas changes the volume proportionally with change in an absolute temperature.
Charles's law describes how gases tend to expand when heated. The following equation can be used: V2 = V1(T2/T1)
An extension of a tool designed to add torque.
Cheater pipes are sometimes prohibited by a company's safety policies.
A slang term referring to the structure of valves on a wellhead.
The technician took a sample at the Christmas tree.
A gas treatment to convert hydrogen sulfide into elemental sulfur by use of a furnace and catalyst.
Approximately 90-95% of recovered sulfur is produced by the Claus process.
The critical point for a mixture is referred to as the state of pressure and temperature at which all intensive properties of the gas and liquid phases are equal.
At the critical point on a phase envelope, the liquid and vapor phases are indistinguishable.
An amine plant using DEA for the reduction of hydrogen sulfide, carbon dioxide, carbonyl sulfide, and other acid gases from sour process streams.
The amine plant was changed from MEA to DEA to minimize corrosion.
A specific secondary amine with the chemical compound formula of HN(CH2CH2OH)2.
DEA is used to remove H2S from a sour gas and allow some CO2 to pass through treated gas.
The process of determining the volatility characteristics of a petroleum product by distilling the product through a range of temperatures.
ASTM D-86 is still referred to as the "Engler Distillation" process.
A branch of the federal government that oversees and enforces the regulation of how humans & industry interact with nature.
The Environmental Protection Agency (EPA) was established on December 2, 1970 amidst increasing public concern about the impact that human activity could have on the environment.
A mathematical formula showing the relationship between the values of the pressure, volume, and temperature for the mass quantity of a particular substance.
EOS modeling was used to estimate the volume of flash gas produced in the production separator train.
Floating production, storage, and offloading vessel used in offshore operations.
FPSOs are typically used offshore where infrastructure is not present and/or possibly cost prohibitive.
A measuring system on a gas chromatograph which ionizes the gas, collecting the ions on plates that produce an electronic signal.
The FID is used on a gas chromatograph because of its high sensitivity.
A portion of mixture of hydrocarbons usually defined by boiling range such as naptha, gas oil, kerosene, etc.
The hydrocarbon component fraction, as determined by a laboratory distillation assay of a composite sample, was found to have a high gasoline content. The hydrocarbon component fraction can be volume, mole, or mass.
The change in gas temperature which occurs when the gas is expanded from a higher pressure to a lower pressure.
Commonly referred to as "JT", the effect for most gases, except hydrogen and helium, is a cooling of the gas. This is a technique utilized when liquifying natural gas. JT can also be used as a backup for cryo-expander plants.
