摘要 |
A continuous process for the combustion of solid fuels under conditions such that flue gas is essentially free of particulates and oxides of sulfur and nitrogen. Fuel is charged as an aqueous slurry and additional water condensed from the flue gas may be recycled to the pressurized combustion zone. Combustion is promoted both by water vapor and alkali added with the fuel slurry, while the alkali serves also to neutralize and remove sulfur in completely oxidized, or sulfate, form. Heat of combustion raises the temperature of the reactants above the critical temperature of water, forming a hot fluid from which useful heat is transferred. Under the pressure of the system, heat recovery results in condensation of water, retaining and slurry product ash and providing recycle water, which helps to control reaction temperature as well as to promote the combustion.
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