| 摘要 |
<p>PROBLEM TO BE SOLVED: To prevent the formation of dioxins by effectively cooling the waste gas from an electric furnace, etc., without causing the deposition/accumulation of dust in a dust and the clogging of a bag filter at an early stage. SOLUTION: A pump rotation number is changed by a control circuit 4 by interposing an inverter device 3 to regulate the spray water quantity supplied to a spray cooling column 1. The spray water quantity, the waste gas quantity flowing into the spray cooling column 1 and the waste gas quantity flowing out from the spray cooling column 1 are detected respectively by each flow rate detector 51, 52 and 53. The control circuit 4 calculates the waste gas quantity flowing out from the spray cooling column 1 from the spray water quantity to be supplied and the flowing in waste gas quantity, assuming that all spray water quantity is evaporated, and the spray water quantity is reduced while the detected effluent waste gas quantity is lower than the calculated effluent waste gas quantity and the spray water quantity is increased when the detected effluent waste gas quantity becomes equal with the calculated effluent waste gas quantity.</p> |
