PROCESS FOR CALCIUM HYPOCHLORITE

摘要

C-8392 AN IMPROVED PROCESS FOR CALCIUM HYPOCHLORITE A process for producing neutral calcium hypochlorite which comprises reacting an aqueous slurry of lime containing insoluble impurities with chlorine in a first crystallizer to form a first slurry of dibasic calcium hypochlorite crystals and insoluble impurities in a calcium chloride mother liquor. The insoluble impurities are separated from the first slurry of dibasic calcium hypochlorite crystals by employing separation means fox classifying solids with respect to particle size. Dibasic calcium hypochlorite crystals are then separated from the calcium chloride mother liquor and admixed with an alkali metal hypochlorite and recycle dibasic calcium hypochlorite crystals in a mixing zone to form a mixing zone slurry. The mixing zone slurry is reacted with chlorine to form a paste of neutral calcium hypochlorite. The paste is separated into a cake of neutral calcium hypochlorite and a paste liquor and the cake of neutral calcium hypochlorite recovered. The paste liquor is reacted with lime in a second crystallizer to form a second slurry of dibasic calcium hypochlorite crystals in a mother liquor. The dibasic calcium hypochlorite crystals are separated from dibasic mother liquor and returned to the mixing zone as recycle dibasic calcium hypochlorite. The novel process can employ low quality lime as it effectively removes insoluble impurities The process also efficiently recovers calcium and hypochlorite values from process streams.