| 摘要 |
The recovery of sulphur values from a flue gas at 800-1000 DEG F containing solid particles entrained therein, SO2, SO3, O2 and water vapour, said flue gas having been produced by the combustion with air of solid-particle-producing, sulphur-containing fuel and containing 0.15-0.2% by volume SO2, comprises separating entrained solid particles to yield a flue gas containing less than 0.01 grain of solids per s.c.f. of gas, contacting the resulting substantially solids-free flue gas at 750-900 DEG F. with a U2O5-containing catalyst suitable to oxidize SO2 to SO3 in the presence of O2, reducing the temperature of the resulting treated gas to below the dew point of H2SO4 present, e.g. 160-280 DEG F. to effect reaction of SO3 with H2O and recovering the resulting condensed H2SO4. The separation of entrained particles may be effected by passing the gas through a filter or cyclone separator and then an electrostatic gas-solids separation zone. The catalyst is preferably in the form of a permeable mass or shallow bed. The water vapour content of the flue gas is preferably in stoichiometric excess with respect to the sulphur oxide content of the flue gas for the production of H2SO4 therefrom. The flue gas may be produced by the combustion of coal, lignite, hard and soft coal, distillate and residual fuel oils useful for power generation. The flue gas typically contains 0.006% by volume SO3 and 0.20% SO2, the other constituents being CO2, CO and N2. |
