Electrocoagulation for wastewater treatment

Electrocoagulation is an alternative method for wastewater treatment. It consists of a destabilization process of water contaminants that are already in suspension, emulsified or dissolved by action of a low voltage, direct electric current and by the action of sacrificial metallic electrodes, usually aluminum or iron.

Electrocoagulation is a compact device, which operates continuously, by means of a specially designed reactor where metal plates or metallic electrodes are placed to produce electrocoagulation. This process generates a high level of cations that destabilize residual pollutants from water, forming complex hydroxides, which are capable of adsorption producing aggregates (flocs) with contaminants. On the other hand, gas forms generating turbulence and pushes floc produced towards the surface.

Another phenomenal benefit of the electrocoagulation process is chemical oxidation that oxidizes metals and non-toxic pollutants as well as substantially degrading the COD / BOD.

Following the electrocoagulation process, waste an aqueous form composed of chemical species of iron bound to arsenic is obtained. This waste must be treated by conventional techniques to separate the most water possible and obtain an easy to manage byproduct with the least possible volume.

Electrocoagulation is a simple operation that requires relatively simple equipment. Because the flocs formed by electrocoagulation contain little surface water, are acid-resistant and are more stable, they can therefore more easily be separated by filtration. Moreover, it is a low-cost technology, which requires low investment and maintenance.

Besides being a technique for treating wastewater, electrocoagulation has also become a very interesting process to be utilized prior to reverse osmosis since it facilitates the process of desalination of water to be treated.