SYSTEM FOR TREATING COAL GASIFICATION WASTEWATER, AND METHOD FOR TREATING COAL GASIFICATION WASTEWATER

摘要

Treating coal gasification wastewater to remove a cyan compound, a fluorine compound, a selenium compound, ammonia nitrogen and a COD component contained in the coal gasification wastewater to achieve satisfactory quality of treated water, to reduce the content of a toxic substance in produced sludge, and disposes waste materials easily. The system is equipped with a high-temperature alkaline chlorination treatment unit for decomposing at least a cyan compound, ammonia nitrogen and a COD component by such a high-temperature alkaline chlorination treatment that an oxidizing agent is added and the reaction is carried out under warmed conditions; a fluorination treatment unit for removing at least a fluorine compound by a coagulation-sedimentation treatment and/or an adsorption treatment; and a selenium treatment unit for removing a selenium compound that the selenium compound is reduced and then the reduced selenium compound is removed and/or an adsorption treatment.

主权项

1. A coal gasification wastewater treatment system for treating coal gasification wastewater containing a cyanide compound, a fluorine compound, a selenium compound, ammoniacal nitrogen, and a COD component, the coal gasification wastewater treatment system comprising:
(1) a cyanide/ammonia/COD treatment unit for decomposing at least the cyanide compound, the ammoniacal nitrogen, and the COD component using a high-temperature alkaline chlorination treatment in which an oxidant is added to be reacted while being heated, (2) a fluorine treatment unit for removing the fluorine compound using at least one of a coagulation sedimentation treatment and an adsorption treatment, and (3) a selenium treatment unit for removing the selenium compound by reducing the selenium compound, and then applying at least one of a removal-by-reduction treatment and an adsorption treatment to remove the reduced selenium compound, wherein the fluorine treatment unit and the selenium treatment unit are arranged downstream of the cyanide/ammonia/COD treatment unit.