| 摘要 |
PROBLEM TO BE SOLVED: To permit sending of gas, having the optimum temperature, into a bag filter and a catalyst tower by a method wherein the waste gas of the outlet port of a boiler and the exhaust gas of a hot-water generating boiler are cooled to a specified temperature while gas, discharged out of a bag filter, is reheated to another specified temperature and refuse in the gas is decomposed to remove the same under catalyst. SOLUTION: A waste heat recovering boiler 2, arranged in the rear stage of a combustion furnace 1, generates hot-water or steam by effecting heat exchange between exhaust gas of 800 deg.C or higher and cold water to regulate the temperature of the exhaust gas so as to become lower than 250 deg.C. Heat exchange between the exhaust gas of the boiler 2 and waste gas discharged out of a bag filter 5 is effected in a heat exchanger 3 whereby the exhaust gas is cooled to about 250-220 deg.C or preferably to 200 deg.C or lower. On the other hand, the gas, discharged out of the bag filter 5, is passed through a pipeline installed in the heat exchanger 3 whereby the gas is reheated to about 160-180 deg.C or preferably 200 deg.C. The reheated gas enters into a catalyst tower 6 and denitration as well as the removal of dioxins are effected in the catalyst tower 6. |
