Effluent Treatment Plant consists of Electrocoagulation which is having pairs of metal sheets called electrodes, which are arranged in pairs of two anodes and cathodes. Using the principles of electrochemistry, the cathode is oxidized (loses electrons), while the water is reduced (gains electrons), thereby making the wastewater better treated. When the cathode electrode makes contact with the wastewater, the metal is emitted into the apparatus.

When this happens, the particulates are neutralized by the formation of hydroxide complexes for the purpose of forming agglomerates. These agglomerates begin to form at the bottom of the tank and can be siphen  out  through  filtration.  However, when one considers an electro coagulation-flotation apparatus, the particulates would instead float to the top of the tank by means of formed hydrogen bubbles that are created from  the anode. The floated particulates can be skimmed from the  top of the tank. 

Since  the  ECF  reactor  is more effective and can  be,  one must  consider  the following  inputs  or variables :

wastewater  type, pH,  current  density,  type of  metal  electrodes (aluminum,  steel,  iron), number of electrodes, size of electrodes, and configuration of metals. These variables would affect the overall treatment time, kinetics, and also the removal efficiency measured.

Further the attached image is self-explanatory about the Electro Coagulation.