Char Burning MHD Systems

This paper indicates the levels of plant thermal efficiency that might be anticipated from three MHD systems (two burning char and oxygen, one burning char and air) featuring reaction of the char and CO₂ leading to a CO-rich gas that would then be oxidized to give a virtually ash-free working fluid. The plants analyzed also featured recirculation of combustion products, somewhat analogously to the semiclosed gas-turbine cycle. Since the gaseous working medium might be quite free from ash constituents if this method of reacting the fuel is successful, rather high air preheat temperatures obtained in regenerative heaters might prove feasible. A further finding is that, if chemical regeneration is employed by reacting the fuel with the gases exhausting from the generator efficiencies in the 55 to 57 percent range may be realized with relatively moderate preheat temperatures.