METHOD FOR COMPENSATING SODIUM LOSS AT PULP MILL, METHOD AND SYSTEM FOR PRODUCING BLEACHED PULP Russian patent published in 2023 - IPC D21C11/00 

FIELD: chemical production.

SUBSTANCE: invention is related to a method for compensating sodium replenishment chemicals for sodium losses caused by leaks in a pulp mill that uses the kraft process to produce pulp. Said pulp mill includes a sulphur conversion unit that is fed with kraft sulphur compounds to convert said sulphur compounds to oxidized sulphur compounds, said process comprising using sodium sulphate or sodium carbonate, or mixtures thereof, as the main replenishing chemical to produce feed sodium replenishing chemicals containing less than 5 mol.% sodium hydroxide, and at least part of the sulphur contained in the replenishing chemical with sodium sulphate, are used to produce oxidized sulphur compounds in the specified plant for converting sulphur compounds.

EFFECT: invention makes it possible to use a smaller amount of replenishing sodium hydroxide to compensate for sodium losses, reduce the discharge of fly ash into the environment, and also produce more sulfuric acid for both internal and external use.

35 cl, 1 dwg