There are three main successive stages to the ECF process:

1) Coagulant formation by electrolytic oxidation of the sacrificial electrode

2) Destabilization of contaminants, suspension of particles and breakage of emulsions

3) Aggregation of destabilized phases to form flocs. Although these principles are general, the technology must be optimized for each different application.

Major factors determining the performance of ECF include the biomass concentration, electrical conductivity, current/voltage, materials of electrodes, etc., in addition to the design of the chamber and overall design and operation conditions of the system. In general, some rules can be provided about the use of ECF for microalgae biomass. The application of ECF to the separation of microalgae produced in freshwater is much more difficult than when produced in brackish water or seawater because low electrical conductivity increases the energy consumption. To process microalgae cultures with low biomass concentration, increases the energy required per kg of biomass mass unit. To reduce the energy consumption the voltage must be reduced as much as possible while maintaining the biomass recovery, for that, the selection of the right materials for electrodes is a key factor, whereas the current will be a function of the design of the chamber/electrodes. The material of electrodes should not be toxic to the valorization of biomass, as well as safe for the cultivation of microalgae when reusing the supernatant, economical and with high efficiency of electro-separation. A common electrode material is an iron (Fe) which has been extensively studied. Current density is influenced by the contact surface of the electrode with the crop, which will determine the electrode cell configuration relative to the culture volume of microalgae to be processed.

:Advantages

• It can lead to better quality effluent
• Metals can be recovered from the solution
• It only requires a low level of electrical current