| 摘要 |
<p>PURPOSE:To recover boronic compounds in a waste discharged gas in a reutilizable form and eliminate the waste liquor in the stack gas desulfurization by the wet lime gypsum method, by adding lime to a liquor discharged form the system to the outside thereof, and spray-drying the resultant mixture. CONSTITUTION:A discharged gas 1 is humidified and cooled in a spray dryer 2, passed through a cyclone 3 and further humidified and cooled with water spray, introduced into an absorbing column 4, brought into contact with a circulating absorbing solution to remove SOx, dust and boronic compounds therefrom. The gas is then passed through a demister 5 and expelled as a clean gas. The circulating absorbing solution is partially taken out by the liquid level control, sent to an oxidizing apparatus 6, and sulfuric acid is added to the absorbing solution to treat and oxidize the unreacted Ca with air and convert the CaSO3 into gypsum. The slurry taken out of the oxidizing apparatus 6 is passed through a storage tank 7 and separated into the gypsum 9 and a filtrate in a separator 8. The resultant filtrate containing the boronic compounds is stored in a preparation tank 10 temporarily. Slaked lime or quick lime is added to the filtrate during the storage to adjust the pH. The filtrate after the adjustment is spray-dried by the heat of the discharged gas 1 in a dryer 2 to recover a solid containing the boronic compounds.</p> |
