Coal is known as black gold and the food for industry. It has been one of the main energy sources used by the human world since the 18th century. Since the beginning of the 21st century, although the value of coal has not been as high as before, coal is still an indispensable source of energy for our human production and life for a long time to come, The supply of coal is also related to the stability of the development of China's industry and even the entire society, and the safety of coal supply is also an important part of China's energy security.