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What is Gas Condensate?

Gas Condensate is a low-density mixture of hydrocarbon liquids that are present as gaseous components in the raw natural gas produced from many natural gas fields. Some gas species within the raw natural gas will condense into a liquid state if the temperature is reduced to below the hydrocarbon dew point temperature at a set pressure.

The natural gas condensate is also referred to as simply condensate, or gas condensate, or sometimes natural gasoline because it contains hydrocarbons within the gasoline boiling range. Raw natural gas may come from any one of three types of gas wells:

Crude oil wells: Raw natural gas that comes from crude oil wells is called associated gas. This gas can exist separate from the crude oil in the underground formation, or dissolved in the crude oil. Condensate produced from oil wells is often referred to as lease condensate.

Dry gas wells: These wells typically produce only raw natural gas that does not contain any hydrocarbon liquids. Such gas is called non-associated gas. Condensate from dry gas is extracted at gas processing plants and, hence, is often referred to as plant condensate.

Condensate wells: These wells produce raw natural gas along with the natural gas liquid. Such gas is also called associated gas and often referred to as wet gas.

 

Composition

There are many condensate sources worldwide and each has its own unique gas condensate composition. However, in general, gas condensate has a specific gravity ranging from 0.5 to 0.8, and is composed of hydrocarbons such as propane, butane, pentane, hexane, etc. Natural gas compounds with more carbon atoms (e.g. pentane, or blends of butane, pentane and other hydrocarbons with additional carbon atoms) exist as liquids at ambient temperatures. Additionally, condensate may contain additional impurities such as:

 

Hydrogen sulfide (H2S)

This traditionally also called mercaptans (denoted as RSH, where R is an organic group such as methyl, ethyl, etc.)

Carbon dioxide (CO2)

Straight-chain alkanes having from 2 to 12 carbon atoms (denoted as C2 to C12)

Cyclohexane and perhaps other naphthenes

Aromatic (benzene, toluene, xylenes, and ethylbenzene)

Drip gas

Drip gas, so named because it can be drawn off the bottom of small chambers (called drips) sometimes installed in pipelines from gas wells, is another name for natural-gas condensate, a naturally occurring form of gasoline obtained as a byproduct of natural gas extraction. It is also known as condensate, natural gasoline, casing head gas, raw gas, white gas and liquid gold. Drip gas is defined in the United States Code, of Federal Regulations as consisting of butane, pentane, and hexane hydrocarbons. Within set ranges of distillation, drip gas may be extracted and used to denature fuel alcohol. Drip gas is also used as a cleaner and solvent as well as a lantern and stove fuel.