摘要 |
FIELD: chemistry. ^ SUBSTANCE: waste water is treated in two steps. First, waste water is treated with lime milk to pH 7.5-8.0. After separation of the precipitate, barium carbonate is added to the clarified water and the obtained suspension is held while stirring until conversion thereof to barium sulphate. After the exchange reaction, barium sulphate precipitate is separated from water. ^ EFFECT: invention enables purification of acidic waste water from heavy metal sulphates lower than the maximum allowable concentration values and sharply reduce residual salt content in the purified water, which enables recycling of the purified water into the production cycle. ^ 1 tbl, 1 ex |