Ore Mining of Coal

The mining of coal is one of the most arduous tasks, and greater efforts are being made to improve working conditions. Due to the different depths of burial of coal resources, the mining method is generally corresponding to the mine mining (deeper burial) and open-pit mining (shallower burial) points. Among them, the proportion of resources that can be mined in the total resources in the proportion of size, is an important indicator of the advantages and disadvantages of the mining conditions, China can be open cast reserves accounted for only 7.5%, the United States 32%, Australia 35%; mine mining conditions are good or bad and the amount of gas in the coal mine inversely proportional to the proportion of gas in China's coal mines, high gas and gas protruding mines accounted for more than 40%. China's coal mining is dominated by shaft mining, which is used in Shanxi, Shandong, Xuzhou and the northeast of China, as well as open-pit mining, such as Shuozhou Pingshuo Coal Mine, the country's largest open-pit coal mine.

More than two-thirds of underground coal production is mined by the room-and-pillar method using continuous mining machinery. Continuous mining machines with tungsten alloy drills break coal from the surface one face to the other before transporting it to cars waiting to be picked up and delivered to conveyor belts to be transferred to the surface. The miner advances a short distance, stops moving and then the support is put in place. This process is repeated until the seam is mined. No blasting is used.

Another underground coal mining method, longwall mining, accounts for about twenty percent of production. This method uses a cutting machine that spans 400 to 600 feet across the coal seam (longwall). This machine has a rotating cylinder tungsten drill bit that cuts down the coal, which is then fed into a conveyor system that brings it out of the mine. The roof is supported by large steel supports that are attached to the machine. As the machine pushes forward, the roof support also moves forward. Nearly 80 % of coal mining can be done using this method.

The remaining eleven percent of underground production is by the traditional dynamite method of mining, where the coal is removed after blasting.

Coal can create asphalt, gas, coal tar and coke

Coal is used as a raw material and is dry distilled in closed ovens (known as coking ovens) at 1,200 degrees Celsius, which results in coal coke with a very high level of fixed carbon content, commonly known as coke