Patent · US Expired

Continuous process for producing granular calcium hypochlorite particles

US4504457A · kind A · utility

2Cited by
9References
8Claims
0Family size

Assignee

Inventor

Key dates

Filing dateSep 30, 1982
Grant dateMar 12, 1985
Priority date
Expiry dateSep 30, 2002

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC01B11/068
  • WIPO fieldMaterials, metallurgy
  • WIPO sectorChemistry

Abstract

A continuous process for producing granular calcium hypochlorite particles comprises admixing lime and an aqueous liquid in a mixing zone to form a lime slurry. The lime slurry is fed into a crystallizing zone along with a calcium hypochlorite-containing liquid to produce a slurry of coarse dibasic calcium hypochlorite crystals and to elutriate a fines slurry from the crystallizing zone. The coarse dibasic calcium hypochlorite crystals are separated from a dibasic hypochlorite mother liquor and fed to a chlorinating zone. Reaction of the coarse dibasic calcium hypochlorite crystals with a chlorinating agent is conducted to produce a slurry of hemibasic calcium hypochlorite crystals. The slurry is fed to a separator to separate a hemibasic hypochlorite mother liquor from the hemibasic calcium hypochlorite crystals. Hemibasic calcium hypochlorite crystals are chlorinated in the presence of an alkali metal hydroxide to produce an aqueous paste of calcium hypochlorite dihydrate which is sprayed into a heated zone to evaporate water and produce granular calcium hypochlorite particles. The novel process of the present invention can employ low grade limes where fine particles including di…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.