又爽又黄又无遮挡网站,亚洲国产福利一区二区三区,小雪第一次交换又粗又大老杨 ,欧美aaaaxxxxx精品

Natural gas industry

Natural gas industry

Natural gas is stored in underground porous rock formations, including oilfield gas, gas field gas, coalbed methane, mud volcanic gas, and biogenic gas, with a small amount also originating from coal seams. It is a high-quality fuel and chemical raw material. Natural gas is mainly used as fuel and can be used to manufacture carbon black, chemicals, and liquefied petroleum gas. Propane and butane produced from natural gas are important raw materials for modern industry. Natural gas is mainly composed of a mixture of gaseous low molecular hydrocarbons and non hydrocarbon gases.