Coal-Fueled Diesel Engine Development Update at GE Transportation Systems

The U.S. Department of Energy is sponsoring a General Electric Company development program for using coal-water slurry (CWS) to power a diesel engine and to test it in a locomotive. The first locomotive system test was successfully completed in 1991 on GE/TS test track. The first-phase coal-fueled 12-cylinder diesel engine used in the locomotive test employed a modified positive displacement fuel injection system and developed 2500 hp in the engine laboratory. The final phase all electric controlled fuel injection equipment (FIE) diesel engine has completed individual component development phases. Combustion research evaluated a broad range of CWS fuels with different source coals, particle sizes, and ash contents. The electronic controlled FIE single cylinder test engine yielded 99.5 percent combustion efficiency. Envelop filters and copper oxide sorbent have been chosen to clean up the engine emissions after extensive evaluation of various hot gas cleaning methods. The projected removal rate of particulate is 99.5 percent and that of SO₂ is 90 percent. Over ten diamond insert injector nozzles performed well on the test engines. A bench test of one nozzle has been run for over 500 engine equivalent hours without significant wear. Tungsten carbide (WC) coated piston rings and cylinder liners were identified to be effective in overcoming power assembly wear. A matrix of WC spray parameters were investigated, and the best process was used to apply coatings onto full scale rings and liners. These and other test parts are currently running in two coal fuel operated cylinders on a converted eight-cylinder endurance test engine. All of these developed technologies will be applied onto the second phase engine and be used in the final phase locomotive test. An economic analysis was also completed on a concept locomotive design. Additional equipment cost and the level of diesel fuel price to repay the investment were analyzed. Thus the economic environment for the commercialization of the modern coal fueled locomotive is defined.