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The Datong Coal Mine Group, in the city of Datong, Shanxi province, has seen a breakthrough in thick coal layer mining, a major problem, Datong Daily reported, on Nov 28, explaining that the project is expected to compete for this year's National Progress in Science and Technology Award.

The project involved an industrial test of the ability to mine about 20 meters underground for the first time in the world and solved many technological problems, including wall rock control, maintaining a mine tunnel far below ground, gas gushing out, and ensuring a safe, efficient mining.

Research began in 2010, led by the coal group team, with support from the Science and Technology Ministry and China National Coal Association. A first trial, at the Tashan Coal Mine, in Datong, was 18.44 meters blow ground, and had an average output above 11 million tons annually. After that, the technology was applied at other sites in the city, and from 2011 to 2013, total production increased to more than 80 million tons, and output value to 25 billion yuan ($4 billion).

The city has long being China's largest coal producer, with resources dating to the Jurassic age mostly depleted, pushing miners to dig into the Carboniferous layers of around 300 to 360 million years ago, which have a complicated structure with an average thickness of 18 meters, making it impossible to use the technology that was applied at that time.

So, 15 research institutes and equipment manufacturers set up a research team for the crucial technology project as part of the 11th Five-year Plan (2006-210). This is the largest research program the coal industry has seen since the founding of the People's Republic of China. In the process, they got 83 patents, wrote six monographs and 237 essays and dealt with occupational standards, independent intellectual property rights, and advanced mining techniques and facilities.