Coal is a solid combustible mineral gradually formed by ancient plants buried underground through complex biochemical and physical-chemical changes.
Coal is called black gold and industrial food. Since18th century, it has been one of the main energy sources used in the human world. Since the 2 1 century, although the value of coal is not as good as before, it is still one of the indispensable energy sources for our human production and life for a long time. The supply of coal is also related to the stability of China industry and even the whole society. Coal supply security is also the most important link of energy security in China.
History:
Although the important position of coal has been replaced by oil, it will inevitably decline for a long time because of the gradual depletion of oil. Due to the huge coal reserves and the rapid development of science and technology, new technologies such as coal gasification have matured and been widely used.
According to the different original materials and conditions of coal formation, coal in nature can be divided into three categories, namely humus coal, residual humus coal and sapropelic coal.
China is the first country in the world to use coal. Coal handicrafts were found in Xinle ancient cultural site in Liaoning, and coal cakes were also found in gongyi city, Henan.