Thirteen people have now been confirmed dead, and another three are still missing following an explosion at a coal mine in Henan Province, China, on Saturday 13 January 2023. The incident happened at 2.55 pm local time, when 425 people were below ground at the Pingdingshan Tian'an Coal Mining Co's No 12 Mine in the city of Pingdingshan, and is reported to have been caused by a gas outburst. A group of miners rescued from a refuge close to the site of the explosion some hours after the explosion were treated for mild oxygen starvation, but all are expected to make a full recovery.
Coal is formed when buried organic material, principally wood, in heated and pressurised, forcing off hydrogen and oxygen (i.e. water) and leaving more-or-less pure carbon. Methane is formed by the decay of organic material within the coal. There is typically little pore-space within coal, but the methane can be trapped in a liquid form under pressure. Some countries have started to extract this gas as a fuel in its own right. When this pressure is released suddenly, as by mining activity, then the methane turns back to a gas, expanding rapidly causing, an explosion. This is a bit like the pressure being released on a carbonated drink; the term 'explosion' does not necessarily imply fire in this context, although as methane is flammable this is quite likely.
Fire is much feared in coal mines due to this combination of flammable gas and solids, with methane and coal dust both potentially explosive when they come into contact with naked flames. To make matters worse, the limited oxygen supply in mines often means that such fires will involve incomplete combustion, in which all the oxygen is used up, but instead of forming carbon dioxide forms the much more deadly carbon dioxide, with potentially lethal consequences for anyone in the mine.
As coal is comprised more-or-less of pure carbon, and therefore reacts freely with oxygen (particularly when in dust form), to create carbon dioxide and (more-deadly) carbon monoxide, while at the same time depleting the supply of oxygen. This means that subterranean coal mines need good ventilation systems, and that fatalities can occur if these break down.
Despite attempts to modernise its energy network, China is still reliant on coal for much of its energy, with 400 000 tonnes of coal mined in China in July 2023, and over 200 million tonnes of coal imported each year, most of it from Indonesia, Australia, South Africa, the United States, and Russia. China has been trying to reduce its dependence on foreign coal by expanding its own coal industry with new mines, but this has come at the cost of more accidents within the industry.
China gains 70% of its energy from coal-burning power stations, which places the country under great pressure to maintain coal supplies. This has led to a poor safety record within the mining sector, particularly in the private sector, where there is a culture of seeking quick profits in poorly regulated (and sometimes officially non-existent) mines. However, the Chinese authorities have been making efforts to remedy this situation, introducing safety regulations and closing (or at least attempting to close) mines that fail to comply. Annual deaths in Chinese mines have steadily fallen from 6995 in 2002 to 245 in 2022 (the latest year for which statistics are available).
Rescue attempts at the Pingdingshan No 12 mine are being co-ordinated by local authorities, with operations at all Pingdingshan Tian'an Coal mines having been suspended due to the high number of accidents which have happened at mines run by the company recently.
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