Waste water purification includes stages of electroflotation with iron dissolution, re-suspension, hydroxide precipitation and floc separation

摘要

Particles separated by flotation are freed of adherent gas bubbles. Shear forces introduced, re-suspend them in the pre-treated waste water. Metal ions are released into solution during electroflotation. By adjusting a basic pH value in solution, the ions are largely transformed into insoluble- or sparingly-soluble hydroxides, and are precipitated. Flocs formed are separated subsequently. An independent claim is included for the corresponding plant. It comprises the electroflotation reactor (2), following reactor (3), stirrer (11), pH measurement instrument (12), dosing equipment and a guide sheet (10) connected to the electroflotation reactor.