Environmental protection application of electrochemical water-treatment

Electrochemical technology  is applied  to environmental water-treatment, it is mainly used in waste-water pretreatment and advanced treatment, as shown in Figure1.At present, The electrocatalytic oxidation technology of Fengyuan company is mainly used for organic removing and modification and the removing of the color and odour. For example, The advanced treatment of biochemical effluent from landfill leachate, pretreatment of landfill leachate membrane concentrate, pretreatment and advanced treatment of nitrobenzene chemical wastewater and advanced treatment and modification of pharmaceutical waste-water .

                                  figue1. The application of electrochemical water-treatment technology

     The principle of electrochemical water treatment technology is mainly based on electrochemical reactions. The common electrochemical reaction is shown in Figure 2.,which are mainly divided into anode reactions, cathode reactions, and particle motion. The core process of anode reaction is that the anode captures the electrons of the reactants near the anode region and occurs an oxidation reaction. The core process of cathode reaction is that the reactant near the cathode region captures the electrons of the cathode and occurs the reduction reaction. The core process of the particle motion is the migration of charged particles and neutral polarization, and  migaration and adsorption occur.

Figue2. Electrochemical reaction

Based on the different electrochemical reactions, different electrochemical water treatment technologies can be generated, as shown in Figure3. Electrochemical technologies based on anode reactions mainly include electrocatalytic oxidation technology, type III electric Fenton technology, and electroflocculation technology. Electrochemical technologies based on cathodic reactions mainly include I/II electro-Fenton technology, micro-electrolysis, electro-floating, electrodeposition, and electro-catalytic reduction,etc. Electrochemical technologies based on particles motion is mainly include electrodialysis, electrodeioinzation, and electrosorption.

 Figure 3 . Electrochemical water treatment technology derived from electrochemical reactions

Different technologies play different roles in environmental protection water treatment, as shown in Figure4.  Electrocatalytic oxidation technology, electrocatalytic reduction, micro-electrolysis, electro-Fenton technology,micro-electrolysis-Fenton technology,etc,mainly used for the degradation and modification of organic pollutants in wastewater. Electrodialysis, electro-deionization, electro-adsorption,and electrodeposition technologies are mainly used to remove inorganic salts and heavy metals in wastewater;  electro-flocculation and electro-floating technologies are mainly used  to remove suspended matter in wastewater and demulsification of emulsions and separation.

                                              Figure 4  Scope of different electrochemical technologies.