Process for recovery of chemicals from pulping waste liquor

Abstract From the Canadian patent

Abstract of the Disclosure:, A process for recovery of chemicals from a sodium sulfite pulping waste: liquor is disclosed in which a smelt obtained from the waste liquor is introduced into an aqueous slurry containing solidified smelt while make up water and a weak aqueous slurry are supplied to effect incompletely dissolving the smelt into the aqueous slurry to maintain the content of total solid and the temperature of the slurry at constant levels, the resulting aqueous slurry is subjected to a solid-liquid separation to obtain a wet cake having the molar ratio of S/Na20 substantially equal to that of the smelt, the wet cake is mixed with hot particles of sodium carbonate and sodium …