Method for treating a salt solution using multistage separation processes, and treatment system for this purpose

2:

• The method as claimed in claim 1, wherein the preliminary classifying device comprises a sorting spiral, wherein the removal of the kainite from the crystallizate suspension is performed by a preliminary removal process which is based on the particle size of the kainite, by the sorting spiral.

3:

• The method as claimed in claim 1, wherein the preliminary classifying device comprises a hydrocyclone, wherein the removal of the kainite from the crystallizate suspension is performed by a preliminary removal process which is based on the particle size of the kainite, by the hydrocyclone.

4:

• The method as claimed in claim 1, wherein the preliminary classifying device comprises an up-current classifier, wherein the removal of the kainite from the crystallizate suspension is performed by a preliminary removal process which is based on the particle size of the kainite, by the up-current classifier.

5:

• The method as claimed in claim 1, wherein a kainite-enriched fraction is transferred from the preliminary classifying device into a thickening device, in which liquid is taken off from the kainite-enriched fraction, so that a useful kainite fraction is taken out from the thickening device.

6:

• The method as claimed in claim 5, wherein the kainite-reduced fraction, before or in the flotation device, is supplied with an anionic flotation assistant and/or a kainite concentrate is taken out from the flotation device and supplied to the useful kainite fraction.

7:

• The method as claimed in claim 1, wherein a flotation residue comprising halite and sylvine is taken out from the flotation device and supplied to a further flotation device, in which a proportion of sylvine is removed from the flotation residue.

8:

• The method as claimed in claim 7, wherein the flotation residue from the flotation device, before or in the further flotation device, is supplied with a cationic flotation assistant.

9:

• The method as claimed in claim 7, wherein a sylvine-reduced and halite-enriched first fraction and a sylvine-enriched and halite-reduced second fraction are removed from the further flotation device, and/or the sylvine-enriched and halite-reduced second fraction is supplied via a return line to the useful kainite fraction and/or the sylvine-enriched and halite-reduced second fraction is supplied to a further, secondary treatment method.

10:

• A treatment system for implementing a method as claimed in claim 1, comprising:
• a preliminary classifying device and a flotation device downstream of the preliminary classifying device, and/or
• a further flotation device downstream of the flotation device.

11:

• The method as claimed in claim 6, wherein the anionic flotation assistant is a sulfated fatty acid or alkali metal salt thereof.

12:

• The method as claimed in claim 8, wherein the cationic flotation assistant is a primary amine.

13:

• The treatment system as claimed in claim 10, wherein the preliminary classifying device comprises at least one selected from the group consisting of a sorting spiral, a hydrocyclone, and an up-current classifier.

14:

• The treatment system as claimed in claim 10, wherein the treatment system further comprises a thickening device.