FREMGANGSMAATE FOR AA GJENVINNE KJEMIKALIER I KJEMIKALIEGJENVINNINGSSYSTEMER MED HOEYT INNHOLD AV KLORIDER VED NATRIUMBASERTE MASSEFREMSTILLINGSPROSESSER.

摘要

A process is provided for the separation of sodium chloride in the sodium chemicals recovery stage of sodium-based pulp manufacturing processes so as to maintain a low sodium chloride content in the recycled sodium chemicals, comprising the steps of treating an aqueous sodium chloride-containing solution with carbon dioxide gas, thereby forming a saturated sodium bicarbonate solution; precipitating sodium values of the solution as sodium bicarbonate while retaining sodium chloride in solution; separating such sodium bicarbonate; withdrawing the residual aqueous sodium chloride-containing solution from the process; and recycling the separated sodium bicarbonate.