| 摘要 |
The invention relates to a process for reprocessing waste solutions from processes in which substances are treated with the solutions, in particular flue gases are purified, and in which the waste solutions, in addition to dissolved alkali metal chlorides and sulphates and alkaline earth metal chlorides and sulphates and typical impurities, contain an organic acid in the form of a salt, in particular calcium formate, by single- or multiple-stage evaporation in vacuo with crystallization of the alkali metal chlorides and sulphates and alkaline earth metal chlorides and sulphates and subsequently separating off the crystallized solid via a separation stage. In order to eliminate the disadvantages occurring in the processes known hitherto and simultaneously reduce the costs for the consumption of chemicals (organic acid or salts thereof) and to produce a calcium chloride product as pure as possible, it is proposed that a portion of the mother liquor from the crystallization stage is returned to the treatment stage of the process, in particular into the scrubber circulation of a flue gas purification plant, or into process stages which serve the treatment stage. <IMAGE>
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