A process for the physical lish - chemical treatment of waste water, in particular from, for the consumption, specific surface water.

摘要

The invention concerns a method for the physico-chemical treatment of effluents in particular surface water for consumption, comprising successive steps of coagulation (A), flocculation (B) and decantation (C), a contact mass being introduced in the water coming from the coagulating step, hence during the flocculating step and this contact mass consists of part of the densified sludge derived from the decanting step and recycled in the flocculating step. This method is characterised in that it consists in injecting in the sludge recycling circuit (16) at least part of the polyelectrolyte ensuring the flocculation.