Fugitive coal mine methane emissions at five mining areas in China

Large quantities (about 28 billion m3) of methane are released to the atmosphere every year from coal-mining activities around the world. This methane represents not only a significant greenhouse gas that is contributing to global temperature change, but is also a wasted energy resource. China, the largest coal producer in the world, is responsible for over 50% of the total global release of methane-containing ventilation air from coal mines. A mine site investigation methodology was developed for collecting reliable methane emission data from coal mines. Five main coal-mining areas in China were studied and specific data were collected from two mines in each of the five mining groups. Information such as coal and methane reserves, ventilation air released, methane concentration and methane release rates were collected. Future development plans were evaluated and used to estimate potential future emissions. It was determined that most of the methane generated in the five mining areas is currently released to the atmosphere.

► Coal mine production and methane data were collected from five mining areas in China. ► More than 15 billion m3 of methane are emitted by Chinese coal mines. ► Over 80% (∼14.7 billion m3) originates from air vented from mines. ► Methane levels in ventilated air are often too low to be used commercially.