Properties Of Natural Gas

Kian Petroleum Company is an international specialized petrochemical company producing various petroleum products such as diesel , Hydrocarbon , etc

Hydrocarbon content

Natural gas is a hydrocarbon mixture consisting primarily of saturated light paraffins such as methane and ethane, both of which are gaseous under atmospheric conditions. The mixture also may contain other hydrocarbons, such as propane, butane, pentane, and hexane. In natural gas reservoirs even the heavier hydrocarbons occur for the most part in gaseous form because of the higher pressures. They usually liquefy at the surface (at atmospheric pressure) and are produced separately as natural gas liquids (NGLs), either in field separators or in gas processing plants. Once separated from the gas stream, the NGLs can be further separated into fractions, ranging from the heaviest condensates (hexanes, pentanes, and butanes) through liquefied petroleum gas (LPG; essentially butane and propane) to ethane

This source of light hydrocarbons is especially prominent in the United States, where natural gas processing provides a major portion of the ethane feedstock for olefin manufacture and the LPG for heating and commercial purposes

Nonhydrocarbon content

Other gases that commonly occur in association with the hydrocarbon gases are nitrogen, carbon dioxide, hydrogen, and such noble gases as helium and argon. Nitrogen and carbon dioxide are noncombustible and may be found in substantial proportions. Nitrogen is inert, but, if present in significant amounts, it reduces the heating value of the mixture; it must therefore be removed before the gas is suitable for the commercial market. Carbon dioxide is removed in order to raise heating value, reduce volume, and sustain even combustion properties

Often natural gases contain substantial quantities of hydrogen sulfide or other organic sulfur compounds. In this case, the gas is known as “sour gas.” Sulfur compounds are removed in processing, as they are toxic when breathed, are corrosive to plant and pipeline facilities, and are serious pollutants if burned in products made from sour gas. However, after sulfur removal a minute quantity of a noxious mercaptan odorant is always added to commercial natural gas in order to ensure the rapid detection of any leakage that may occur in transport or use