METHOD OF CAUSTIFICATION OF GREEN LIQUOR Russian patent published in 2018 - IPC D21C11/00 

FIELD: technological processes.

SUBSTANCE: method of causticizing green liquor in the sulfate or craft process of cellulose production, in which green liquor, consisting of an aqueous solution of sodium carbonate as the main component and sodium sulphide, is admixed in an apparatus for slacking lime with calcium oxide and in causticizer (10) is converted to an aqueous suspension, containing sodium hydroxide and calcium carbonate as the main components, this suspension is filtered on first filter (19) and then two to three times after dilution with water in dilution tank (21, 25) to separate the solids suspended therein is sent through additional filters (22, 26) and filtered, according to the invention, carbon dioxide is added into an aqueous suspension after the first separation of calcium carbonate as the main component and calcium oxide as a by-product component at least during dilution in dilution tank (18, 21, 25) and, in particular, in this dilution tank or tanks (21, 25) before second and/or third filter (22, 26).

EFFECT: method for causticizing green liquor in the sulfate or craft process of cellulose production is proposed.

13 cl, 2 dwg, 2 ex, 2 tbl