Gas Turbine Systems Designed for Coal Water Slurries
Numerous attempts have been made during the past two decades to develop advanced power generation systems which could burn coal or coal-derived fuels both economically and in an environmentally acceptable manner. Although much valuable technology has been derived from these programs, commercially viable power generation alternatives have not yet appeared. One prospective way to expedite the commercialization of advanced coal-fired power systems is to meld the latest gas turbine technology with the emerging technology for producing slurries of water and ultra clean coal. This paper describes a DOE-sponsored program to identify the most attractive gas turbine power system that can operate on slurry fuels. The approach is to use slurries produced from finely ground (<10 microns) coal powder from which most of the ash and sulfur has been removed. The gas turbines will incorporate a rich-burn, quick-quench combustor to minimize conversion of fuel-bound nitrogen to NOx, advanced single crystal alloys with improved hot corrosion resistance and strength, advanced metallic and ceramic coatings with improved erosion and corrosion resistance, and more effective hot section cooling. Two different power plant configurations are covered: a large (nominally 400 MW) combined cycle plant designed for base load applications; and a small (nominally 12 MW) simple-cycle plant designed for peaking, industrial, and cogeneration applications.