| 摘要 |
<p>PURPOSE:To enable an efficient treatment of a waste liquid in a flue gas treatment apparatus by injecting a controlled amount of a circulating liquid into an upper stream of a dry dust collector so as to collect dried solid materials, while the flue gas undergoes a dry dust collection and wet treatments and the absorbing liquid is supplied to a cooling tower and an absorption tower. CONSTITUTION:A flue gas 2 from a boiler 1 is sent to a dry dust collector 3 to have soot and dust removed. A dedusted gas 5 is next introduced into a cooling tower 6 by way of a gas heater 33, wherein halides, soot and dust are removed, then introduced into an absorption tower 6 to have SOX removed and discharged as a clean flue gas 9. A washing liquid in the cooling tower 6 is circulated through a circulating line 11 and a part of the circulating gas is sent to a neutralizing tank 25, wherein gypsum is formed by an alkali reagent from a line 24. A slurry formed in the tank is sent to an evaporator 27 by way of a line 26, wherein the slurry is evaporated and dried, and dry materials formed are collected by the dry dust collector 3. Under these circumstances, a take-out quantity of the circulating liquid is controlled by a valve 41 so that a lowering of the flue gas temperature becomes 4-8 deg.C by a signal 39 sent to a controller 40 concerning a boiler load or a flow rate of flue gas.</p> |
