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

摘要

PURPOSE: To recover valuables such as vanadium, ammonia or the like from collected ash and waste drain water to regenerate the same in high purity while reducing the vol. of formed sludge to enable stable operation. ;CONSTITUTION: After collected ash (b) is mixed with waste drain water (a) to be slurried and reduced in vol., a reducing agent C such as a ferrous salt reducing pentavalent vanadium to tetravalent vanadium in order to recover vanadium of the formed slurry is added to the slurry and an alkali agent such as magnesium hydroxide and/or aq. ammaonia are further added to adjust the pH of the slurry to 3-9 to precipitate tetravalent vanadium as tetravalent vanadium hydroxide. The precipitate (c) containing precipitated vanadium hydroxide in high concn. is separated and calcium hydroxide is further added to the separated soln. containing no vanadium hydroxide to adjust the pH of the separated soln. to 9-12 to form magnesium hydroxide and moisture is evaporated by distillation to concentrate the separated soln. When calcium hydroxide is added, the ammonium ion in the soln. is recovered as aq. ammonia.;COPYRIGHT: (C)1996,JPO