| abstract |
(57) [Summary] PROBLEM TO BE SOLVED: COD component, fluorine, etc. from waste water of a wet flue gas desulfurization unit that absorbs and removes sulfur compounds in coal combustion exhaust gas. Heavy metals and the like are efficiently and sufficiently removed. SOLUTION: A COD component decomposition step 1 in which an oxidizing agent is added to waste water to decompose a nitrogen-sulfur-containing compound and then decompose and remove an excess oxidizing agent with a reducing agent, a chelating agent for collecting heavy metals, An aluminum compound and a pH adjusting alkali agent are added to precipitate and separate a solid containing fluorine and heavy metals (A) 2; and sodium carbonate and a pH adjusting alkali agent are added, and calcium is added. Precipitation step (B) 3 for precipitating and separating solids containing fluorine and fluorine, and contacting with activated carbon to form organic CO 2 Activated carbon adsorption step 7 for adsorbing and removing the D component, and after contacting with a fluorine adsorbing resin to adsorb and remove the remaining fluorine, A method for treating flue gas desulfurization wastewater, comprising: a fluorine adsorption step 8 of adjusting the pH to 5.8 to 8.6 with an alkali agent. |