According to Baidu Encyclopedia, the main raw materials of cement are limestone, gypsum, fly ash, clay and iron slag. Coal and petroleum are energy sources, and coal ash, water and carbon dioxide remain after coal combustion; Petroleum refines gasoline, diesel oil, etc. Water and carbon dioxide are produced after combustion.

Petroleum refers to the mixture of natural gaseous, liquid and solid hydrocarbons. Petroleum is divided into crude oil, natural gas, natural gas liquid and natural tar, but it is customary to use "oil" as the definition of "crude oil".