创新能源与研究

抽象的

An Overview of Coal energy

Markus Kraft

Coal is a combustible black or brownish black sedimentary stone framed as rock layers called coal seams. Coal is generally carbon with variable amounts of different components, mostly hydrogen, sulfur, oxygen, and nitrogen. Coal is formed when dead plant matter rots into peat and is changed over into coal by the heat and pressure of deep burial over millions of years. Vast deposits of coal start in previous wetlands called coal woods that covered a significant part of the Earth's tropical land regions during the late Carboniferous (Pennsylvanian) and Permian times. However, numerous critical coal deposits are more younger than this and orginated from the Mesozoic and Cenozoic times.