Dust collection ash of heavy oil fuel kindling boiler and hybrid manipulation manner null

摘要

PROBLEM TO BE SOLVED: To provide an efficient mixing treatment method of collected ash generated from the dust collector of the exhaust gas of a boiler using heavy oil as fuel and waste water generated from an exhaust gas desulfurizer. ;SOLUTION: The collected ash (b) of the exhaust gas from a boiler and the desulfurization waste water (a) from a wet exhaust gas desulfurizer 9 are mixed and a reducing agent is added to the resulting mixture to reduce pentavalent vanadium to tetravalent vanadium and magnesium hydroxide and/or aq. ammonia is added to the obtained mixed soln. to adjust the pH thereof to 3-9 to separate formed high concn. vanadium-containing precipitate and calcium hydroxide and/or calcium oxide is further added to the separated soln. (h) to adjust the pH thereof to 9-12 and this soln. is distilled to recover aq. ammonia k' and calcium sulfate and magnesium hydroxide (g) in the distilled residual soln. are separated to obtain a slurry based on calcium sulfate and this slurry is supplied to the wet exhaust gas desulfurizer 9 to recover gypsum.;COPYRIGHT: (C)1998,JPO