摘要 |
FIELD: water-supply engineering. ^ SUBSTANCE: invention relates to methods of removing hardness salts from regenerates and can be used in water treatment processes in heat-and-power engineering, chemical, petrochemical, food, and other industries provided with ion-exchange water-desalting filters. Method is accomplished by precipitation of hardness salts involving recycle of precipitate treated by alkali solution followed by passage of supernatant through H-cationite filter. Treated precipitate accumulated in preceding settling cycles is recycled into regenerate and settling-subjected solution is passed through cationite filter to produce purified sulfuric acid further used for regeneration of H-cationite filters in water-treatment cycle. Precipitate is treated with alkaline regenerate from OH-anionite filters or with alkali solution obtained from electrolysis of regenerates with pH not below 11. Amount of regenerate introduced into accumulator-settler should be at least 20 kg/m3. ^ EFFECT: excluded liming procedure, preserved initial (after regeneration of filters) content of sulfate ions in sulfuric acid, reduced consumption thereof during preparation of regeneration solution, and excluded discharge of sulfate ions unto water objects. ^ 3 cl, 2 ex |