DEODORIZER PRODUCED BY USING FERRIC HYDROXIDE-CONTAINING WET NEUTRALIZED SLUDGE AS PRODUCTION RAW MATERIAL, AND METHOD FOR PRODUCING THE SAME

摘要

PROBLEM TO BE SOLVED: To provide a liquid deodorizer produced by using ferric hydroxide-containing wet neutralized sludge as an iron production raw material, which deodorizer can be suitably used for the storage of concentrated sludge or the like forming hydrogen sulfide, which is a malodorous substance, in a high concentration in treatment facilities for wastewater, such as municipal sewage, or their incidental facilities or the like, and to provide a method for producing the same.;SOLUTION: The liquid deodorizer is produced by using the ferric hydroxide-containing wet neutralized sludge, which is formed when an acidic waste liquid containing an iron compound is neutralized, as the production raw material. The production method of the liquid deodorizer includes mixing the sludge with nitric acid having a concentration of ≥20 wt.% in an NO₃/Fe molar ratio of 3.0-6.0 and dissolving the sludge by heating at a temperature of 60-100°C for 1-12 hours. The liquid deodorizer is an aqueous solution containing 7-35 wt.% of ferric iron in terms of Fe₂O₃, having the NO₃/Fe molar ratio in the range of 3.0-6.0 and having an SO₄ concentration of ≤1.6 wt.%.;COPYRIGHT: (C)2012,JPO&INPIT