Low BTU Fuels for Gas Turbines

Abstract

The current shortage of conventional gas turbine fuels has created the need for new sources of “clean” fuel. One of the most promising new fuels is low Btu gaseous fuel, such as produced by air injected coal or oil gasifiers or other chemical processes. The various sources of low Btu fuels and their combustion characteristics are discussed. To burn many of the low Btu fuels in the 100–300 Btu/scf range necessitates certain design modifications to the gas turbine originally optimized for high energy fuels. The extent of the modification depends greatly on the low Btu fuel. The impact of low Btu fuels on the gas turbine thermodynamic cycle performance and environmental performance is very encouraging. From the environmental viewpoint, low Btu fuels promise to be “clean” fuels while providing increased output at higher thermal cycle efficiencies than achieved with conventional fuels.