CHLORINE BYPASS EXHAUST GAS TREATMENT METHOD AND CHLORINE BYPASS SYSTEM

摘要

PROBLEM TO BE SOLVED: To stably treat a chlorine bypass exhaust gas while suppressing equipment cost to be low.SOLUTION: While a part G1 of a combustion gas is cooled, extraction is performed from a kiln exhaust gas flow passage from the tail of a cement kiln 2 to the lowermost cyclone, and chlorine bypass dust D5 is recovered from extraction gases G3, G4. The gas G5 after the recovery is added with a powdery desulfurizing agent DA, and before the gas G6 after the addition of the desulfurizing agent is joined to the exhaust gas system of a cement firing apparatus, dust is removed from the gas after the addition of the desulfurizing agent. It is possible that a part of the dust removal dust D6 is added to the gas after the recovery of chlorine bypass dust as a part of the desulfurizing agent, and is added to cement. It is possible that, after the recovery of the chlorine bypass dust, the concentration of SOin the gas before and after the addition of the desulfurizing agent is measured, and the addition amount of the desulfurizing agent can be controlled in accordance with both SOconcentrations.SELECTED DRAWING: Figure 1