HYGAS

Coal gas is a term referring to town gas made from coal. Town gas is a more general term referring to all manufactured gas produced for sale to consumers and municipalities. Note: the terms - manufactured gas, syngas (SNG), hygas, and producer gas - are also common in some countries.Prior to the development of natural gas supplies and transmission, in both the United States and Great Britain, during 1940s and 1950s, virtually all fuel and lighting gas used in these countries was manufactured from coal. Depending on the processes used for its creation, coal gas is a mixture of caloric gases: hydrogen, carbon monoxide, methane, and volatile hydrocarbons with small amounts of noncaloric gases carbon dioxide and nitrogen as impurities. Coal gas plants, especially those that operated historically, are most commonly referred to today by environmental professionals, and within the utility industry, as Manufactured Gas Plants or "MGPs."
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