With China as a major coal producer, the annual output ranks first in the world. Coal has always dominated China's primary energy production and consumption structure. It is predicted that by 2020, coal will account for 60% of China's primary energy production and consumption structure. Around, even by 2050 will still account for more than 50%. However, due to the complexity of natural conditions, the geological conditions and operating environment of coal mining in China are relatively harsh, which makes the mining personnel in a difficult environment. As the mining depth increases, the coal output increases sharply, and the safety investment and safety are safe. The technical, safety equipment and safety management are not in place, and the safety production situation of China's coal mines is very serious.
It is estimated that the economic losses caused by coal mine accidents each year will reach more than 5 billion yuan. In addition, indirect economic losses such as personnel disability, occupational diseases and suspension of work due to coal mine accidents are even more difficult to estimate. From Table 1-1, it can be seen that there are no more than 100 coal mine accidents per year, resulting in more casualties and hundreds of millions of property losses. Since 2013, the death rate per million tons has been 0.293, and it has dropped to 0.3 for the first time in history. Below, although the death rate per million tons in 2017 was 0.106, it is about several times that of advanced countries compared with advanced coal-producing countries.
It is obvious in Table 1-1 that gas accidents (including gas ventricle, gas combustion, gas explosion, gas outburst) in these accidents have always occupied a large proportion, and the mortality caused is extremely high. Coal mine gas has a great impact on the safety of production. The threat is also the main cause of disasters in coal mining enterprises, and it is the most prominent problem in coal mine safety production. Coal dust and toxic and harmful gases in the underground gas environment are the accomplices of gas accidents. Therefore, studying the underground gas environment detection and safety assessment is of great significance to the safe production of coal mines.