| 摘要 |
<p>PURPOSE:To attain high desulfurization efficiency by recovering the waste gas primarily desulfurized in a furnace and coal ash drawn out of a boiler after primary desulfurization in a spray dryertype desulfurizer and carrying out secondary desulfurization in the desulfurizer. CONSTITUTION:A small amt. of a desulfurizing agent (e.g. limestone) and coal grains are fluidized in a coal-fired fluidized-bed combustion boiler 1 in the primary desulfurization stage. In the secondary desulfurization stage, the dust discharged from the boiler 1 after primary desulfurization, the coal ash drawn out of the boiler, etc., are recovered in a spray dryer-type desulfurizer 6, and the unreacted Ca source contained in the dust and coal ash is utilized in the desulfurizer 6. Consequently, the amt. of desulfurizing agent to be used for the primary desulfurization is reduced, and the combustion in the pressure fluidized-bed combustion boiler and atmospheric fluidized-bed combustion boiler is stabilized. Further, the unreacted Ca source from the primary desulfurization is effectively utilized, and high desulfurization efficiency is attained.</p> |
