| 摘要 |
<p>PROBLEM TO BE SOLVED: To suppress the concentration of hydrogen chloride in exhaust gas and adjust the pH of fly ash captured from exhaust gas in an appropriate range.SOLUTION: An exhaust gas treatment apparatus comprises a hydrated lime supply device 14 supplying hydrated lime to exhaust gas, a fly ash treating agent supply device 16 supplying a fly ash treating agent containing a ferrous salt to exhaust gas, a filter 10 capturing fly ash in exhaust gas, a fly ash treatment apparatus 18 kneading the captured fly ash with hydrated lime and the fly ash treating agent, a hydrogen chloride concentration detector 20 detecting a concentration of hydrogen chloride after filtration, a hydrogen chloride concentration controller 22 causing the hydrated lime supply device 14 to supply hydrated lime so that the detected concentration of hydrogen chloride approaches a target value and a fly ash treatment controller 24 determining the amount per unit time of the fly ash treating agent supplied for neutralization of unreacted hydrated lime on the basis of the detected concentration of hydrogen chloride and the amount per unit time of hydrated lime supplied and causing the fly ash treating agent supply device 16 to supply the fly ash treating agent by the determined supply amount.</p> |
