| 摘要 |
PROBLEM TO BE SOLVED: To obtain a highly concentrated sulfuric acid without the necessity to use a sulfur oxide absorbent and a large-scale desulfurization installation by introducing an exhaust gas containing a sulfur oxide into an absorption column and spraying water to the exhaust gas to increase the moisture content of the exhaust gas and cool it, and further subjecting the exhaust gas to a desulfurization reaction while water is supplied to an active carbon fiber layer. SOLUTION: An exhaust gas containing a sulfur oxide discharged from a boiler 1 is cooled by a gas-gas heater 3 and dust is removed from the exhaust gas by a dust collector 4. Next the gas is sucked by a fan 2 to be introduced into an absorption column 6 through an introduction aperture 5 located at the lower part of the column 6. After that, water is sprayed to the exhaust gas from a water sprayer 7 in the absorption column 6 to increase the moisture content of the exhaust gas and cool it, and the gas is made to pass through an active carbon fiber layer 8 for desulfurization reaction and take its ascent. In this case, the water is supplied to the layer 8 from a water supplier 9 so that the water is left adhering to the surface of active carbon fibers. Thus it is possible to turn SO2 contained in the exhaust gas to SO3 by oxidation and at the same time, process SO3 into sulfuric acid (H2 SO4 ). Next the sulfuric acid is made to drop from the layer 8 to be recovered and is sent under pressure by a pump 10 to a sulfuric acid storage tank 11. |
