Coal mining involves the extraction of solid mineral resources in underground and open-pit mines, and activities such as sorting, washing, briquetting, etc. that result in marketable products.
Methane is a greenhouse gas which is 21 times more potent than CO2. Whilst operating a coal mine methane gas is released into the mineshaft. To avoid an explosive atmosphere the mines have to be vented. This leads to ventilation air methane (VAM), which can be transformed to CO2 in order to earn carbon credits. For this application Dürr LTB Ecopure® RTO regenerative thermal oxidiser technology is a proven solution, able to run “autothermally” (i.e. without any additional fuel) at low methane concentrations. The carbon credits generated ensure a relatively short payback period.
Rising energy prices and the discovery of large reserves of natural gas in shale formations (shale gas), particularly in the USA, have created a whole new industry sector dedicated to the extraction of the deep-lying unconventional gas fields by hydraulic fracturing (fracking).
Aside from the much-debated overall environmental impact of the fracking industry, the drilling and fracturing process and associated site operations also produce emissions of VOC – principally BTEX (benzene, toluene, ethylene, xylene) compounds – and methane (which is typically flared-off). Subject to site conditions, RTO technology offer one a potential way to control the VOC – typically a combination of polynuclear aromatic hydrocarbons (PAH) and harzardous air pollutants (HAP).