Chementator: Coal-Mine Vent Air

Megtec Systems (Glen Waverly, Victoria, Australia; edlinks.chemengonline.com/6902-542) has announced the first power plant fueled by methane emissions from coal-mine ventilation air. Traditionally, CH₄ released during coal excavation requires dilution in ventilation air because it is explosive at concentrations between 5 and 15%; and, typically, the gas is kept at below 1% for safety. Using a proprietary regenerative thermal oxidizer, the Megtec plant can run a 6-MW turbine on "high-grade," super-heated steam generated from the combustion of 0.9% methane-content air. The technology allows Megtec’s clients, BHP Billiton (Melbourne, Victoria, Australia), to claim carbon credits equivalent to their mine’s reduced exhaust CH₄ — a greenhouse gas 20 times more potent than CO₂.