Maturation of the basic technical knowledge base relating to coal processing, handling, and combustion; materials of construction; and systems design of gas turbines has provided an opportunity to revisit the concept of direct coal firing in a gas turbine. The U.S. Department of Energy (DOE) initiated a scoping program beginning in 1983, and based on promising results has recently entered into a second significant phase of research and development that will lead to proof of concept within 5 years. Four major turbine manufacturers are participating with the DOE along with numerous universities, independent R&D labs, and the national laboratories. Expenditures in the tens of millions of dollars range are expected.
Results to date are very encouraging with respect to gas turbine combustion designs, including slagging, nonslagging, and staged (rich/lean) configurations; deposition phenomena and control; particulate removal; alkali release and control; SOx control; and NOx control.
Systems studies by the leading U.S. locomotive manufacturers and the DOE have been completed. They indicate that a coal-fired gas turbine in a locomotive is a viable option worthy of further development with the promise that it will be economically competitive with oil-fired diesel/electric systems and with coal-fired diesels. These alternate options are being explored in a separate part of DOE/industry programs. This paper addresses the progress made in key technology areas and the economic benefits that will exist if these technology developments bear fruit.