The physico-chemical treatment consists in the removal of contaminants in suspension through the addition of chemicals, forming insoluble compounds and, consequently, that can be removed by physical separation processes. They can be arranged in: - Physical - chemical methods. - Dissolved air flotation.

Physical-Chemical Methods

Physical-chemical methods are varied and applied to remove specific contaminants present in water and / or effluents. This stage of the treatment is dimensioned through the use of reactors in which the chemical agents stimulated by the physical action (agitation and mixing) are applied. According to the industrial activity generation regime are configured with the continuous treatment regime or by batch. The steps are composed: Coagulation step: addition of chemicals with rapid agitation to increase the contact between molecules through chemical reactions. Flocculation stage: In this stage slow mixing occurs which will provide the formation of particles called flakes, more dense than water. Decantation step: it is a process of physical separation the molecules with greater weight than the water are decanted and removed for pressing process moved to the pressing process. 

Dissolved air flotation

They have the steps of coagulation and flocculation, but these occur in the pipes, which increases the efficiency in the chemical reaction (agitation and mixing). In the stage of physical separation occurs through the insufflation of dissolved air adjusted to the particle sizes, increasing its thrust and causing its ascent.