| 摘要 |
<p>PURPOSE:To attain the re-utilization of ammonia in waste water and to dispense with a waste water treating apparatus, by finely pulverizing the waste liquid from a wet exhaust gas treating apparatus by pressurized ammonia gas before injecting the same into the upstream side of a dry dust collection apparatus. CONSTITUTION:The waste liquid sent to a spray water tank 41 from a cooling and absorbing tower 108 is injected into the exhaust gas 2 of a heavy oil firing boiler 1 by an NH3 injection apparatus 27 while finely pulverized by pressurized NH3 gas 40. The dry solid substance or soot such as (NH4)2SO4 formed by the reaction with SO3 in the exhaust gas is collected by a dry dust collection apparatus 3. Subsequently, the exhaust gas 5 is heat exchanged with purified exhaust gas 9 and, thereafter, guided to the cooling and absorbing tower 108 where SOx and soot are absorbed and removed by a washing solution of limestone. The slurry containing CaSO3 is sent to an oxidizing tower 16 to form a gypsum slurry and gypsum 20 is separated by a solid-liquid separator 19. A part of the filtrate 21 is sent to the cooling and absorbing tower 108 and the remainder is supplied to the spray water tank 41 while a valve 39 is adjusted by a detector 37 and a regulation meter 38 so as to make the concn. of the suspended substance constant.</p> |
