Midstream

Midstream Glossary

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For questions regarding incorrect/outdated entries or suggestion for adding additional terms, please contact Martin Erne

Term
Definition
Common Use Examples
looping

Adding piping with a connection to an existing line at each end.

looping
Adding piping with a connection to an existing line at each end.

make-up gas

(1) In contractual terms, the amount of gas delivery specified for which a buyer has paid for but not taken. (2) In gas processing, the amount of gas required to keep the inlet volume or energy whole at the outlet. This is typically defined by contract or regulation. (3) In gas analysis, the additional carrier gas added upstream of the detector to achieve optimal flow

make-up gas
(1) In contractual terms, the amount of gas delivery specified for which a buyer has paid for but not taken. (2) In gas processing, the amount of gas required to keep the inlet volume or energy whole at the outlet. This is typically defined by contract or regulation. (3) In gas analysis, the additional carrier gas added upstream of the detector to achieve optimal flow

marketable gas

Gas, which meets the purchaser's specifications.

marketable gas
Gas, which meets the purchaser's or the transporter's specifications.

mercaptan

Any of a series of compounds of the general formula RSH, analogous to the alcohols and phenols, but containing sulfur in place of oxygen. "R" in the formula above represents the hydrocarbon radical. I.e., methyl-, ethyl-, propyl-, etc.

mercaptan
Any of a series of compounds of the general formula RSH, analogous to the alcohols and phenols, but containing sulfur in place of oxygen. "R" in the formula above represents the hydrocarbon radical. I.e., methyl-, ethyl-, propyl-, etc.

methane

The lightest member of the aliphatic hydrocarbon series, with a chemical formula of CH4.

methane
The lightest member of the aliphatic hydrocarbon series, with a chemical formula of CH4.

methanol (methyl alcohol)

The lightest alcohol, having the chemical formula CH3OH.

methanol (methyl alcohol)
The lightest alcohol, having the chemical formula CH3OH.

methyl mercaptan
A colorless, flammable, gas compound of disagreeable odor.

mist extractor

Vessel internals which remove free liquid from gas.

mist extractor
Vessel internals which remove free liquid from gas.

modular plant

A gas processing facility built primarily in off-site shops on fabricated skids and shipped to the facility site upon completion.

modular plant
A facility built primarily in off-site shops on fabricated skids and shipped to the facility site upon completion.

mole percent
A unit of concentration representing the number of molecules of a component in a mixture relative to the total number of molecules in the mixture, expressed as a percentage.

molecular sieves

Synthetic zeolites packaged in bead or pellet form.

molecular sieves
Synthetic zeolites packaged in bead or pellet form.

naphtha
A mixture of hydrocarbons, mostly pentanes and heavier, with a maximum final boiling point of about 400oF.

naptha

A mixture of hydrocarbons, mostly pentanes and heavier, with a maximum final boiling point of about 400oF.

natural gas

A hydrocarbon mixture that exists in a vapor phase consisting of primarily methane and commonly includes various amounts of other hydrocarbons, carbon dioxide, nitrogen, hydrogen sulfide, and/or helium.

natural gas
A hydrocarbon mixture that exists in a vapor phase consisting of primarily methane and commonly includes various amounts of other hydrocarbons, carbon dioxide, nitrogen, hydrogen sulfide, and/or helium.

natural gas liquids (NGLs)
Liquid-phase hydrocarbons primarily derived from a natural gas stream.