New Cycles for Methanol-Fuelled Gas Turbines

Abstract

Assuming that methanol is employed as fuel, the heat released from the gas turbine discharges can be used to cause an endothermic catalytic reaction: CH3 OH + H2 O + heat → 0,5 CO + 0,5 CO2 + 2,5 H2 + 0,5 H2 O; this produces a gaseous fuel, the lower heaving value of which exceeds that of methanol by 18%. Combining both steam reforming of methanol and steam injection in the combustor by using the maximum heat available in the exhaust gases, very interesting cycle characteristics can be achieved (more than 50% efficiency (LHV basis), same capital cost per kW as simple cycle gas turbine (9000E engine), low emissions of NOx and SO2). Reheating the gas during the expansion will improve the efficiency by 2–3 points allowing an increase in power output without increasing the capital cost per kW. At the end of the century, these types of cycles could be applied to all the new, non-nuclear power plants in the French energy system. The annual cumulative duration of such generators will not be greater than 2000 hours.