| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide an operation method of a waste gas treatment apparatus for removing dioxins by realizing an optimum operation temperature so as to demonstrate stable performance. SOLUTION: Hydrochloric acid concentration of a waste gas is lowered to a specified level in a lime spray tower and sprayed lime together with ash is collected by a dust collector. Then, waste gas temperature is controlled to a temperature of 120-160 deg.C by a heat exchanger and is guided into an adsorption tower filled with granular active carbon in order that SO2 and dioxins are adsorbed by the granular active carbon. NOx is decomposed by NH3 introduced into a flue of the heat exchanger and a part of it together with dust is filtered and removed as NH4 Cl by the active carbon in the adsorption tower. Then, the active carbon which has adsorbed SO2 , dioxins and HCl is guided into a desorption tower, and the SO2 is desorbed, the dioxins are decomposed and the HCl is desorbed and the active carbon which has undergone desorption and regeneration is separated into granular active carbon, dust and active carbon powder by a sieving device. The granular active carbon is returned to the adsorption tower, desorbed gas is returned to the lime spray tower so as to be desalted and the SO2 is fixed by the lime, and the dust and active carbon powder are returned to a furnace or the lime spray tower.</p> |
