Electrocoagulation Water Treatment System
The electrocoagulation water treatment system process is based on valid scientific principles involving responses of water contaminants to strong electric fields and electrically induced oxidation and eduction reactions. This process is able to take out over 99 percent of some heavy metal cations and also able to precipitate charged colloids and remove significant amounts of other ions, colloids, and emulsions. Electrocoagulation water treatment system is based on the reactive anodes principle. It is a question of generating metallic cations (Al3+ or Fe3+) in wastewater by imposing a D.C. current between the electrodes. These cations act as a coagulant and lead to the destabilization of suspended particles and colloidal structure.
During the treatment, electrolysis reactions between the electrodes make it possible to produce micro bubbles. These finely divided bubbles drag suspended matter with them as they rise to the surface: hydrocarbons, oils, greases and colloids. At the end of the process, treated and decontaminated water is obtained. Electrocoagulation water treatment system is a technology that can be useful to all industries generating mineral or organic pollution. This Technology is ideally suitable for treating Textile Dyes Effluent
Electrocoagulation is the process of destabilizing suspended, emulsified or dissolved contaminants in an aqueous medium by introducing an electrical current into the medium. The electrical current provides the electromotive force to drive the chemical reactions. When reactions are driven or forced, the elements or compounds will approach the most stable state. Generally, this state of stability produces a solid that is either less colloidal and less emulsified (or soluble) than the compound at equilibrium values. As this occurs, the contaminants form hydrophobic entities that precipitate and can easily be removed by a number of secondary separation techniques.
Electrocoagulation is an Unique and Latest technology successfully implemented in Developed and Developing Countries. The Advantages of electrocoagulation water treatment system ETP are as follows.
No addition of Chemicals, Lime or Ferric.
Very Low Operating Cost.
Less requirement of Space and Civil Construction.
Easy to maintain and operate.
Colour Removal more than 95%.
Electrocoagulation Water Treatment Process
Electrochemical techniques are important for the treatment of Textile wastewater because they present high efficiency, easy operation and environmental compatibility; this process involves in sit generation of coagulants by electrolytic oxidation of a sacrificial anode (iron) by applying a direct current. The most widely used electrode materials in electro coagulation process are iron. The hydrolyzed iron ions can form long chains of Fe-O-Fe-OH which may chemically adsorb a large amount of contaminating .For most applications a proper removal of all impurities ( Physical, biological and Dissolved impurities) of the water reused, is required.
After biological treated water is secondary clarifier and remove suspended particles and fed in to electrocoagulation water treatment system. The electro coagulation process works at input feed PH is 6.0 to 8.0 and conductivity >2000 milligrams/litre. Before and after were monitored for color, turbidity, pH and chemical oxygen demand reduction efficiency. Normally electro coagulation process reduces COD 50 to 60 % from input COD of electrocoagulation water treatment system process .
- Dissolution of metal ions from an electrode by applied potential.
- Simultaneous evolution of H2 gas bubbles.
- Destabilisation of suspension coagulation.
- H2 bubbles promote flotation, but also sedimentation may occur.
- Pair(s) of Fe or Al parallel plate electrodes separated by a few mm.
Electrocoagulation Chemical reaction
Main reactions occurring at the electrodes are:
In addition, Fe3+ and OH- ions generated at electrode surfaces react in the bulk waste water to form ferric hydroxide:
The iron hydroxide flocs act as adsorbents and /or traps for pollutants and so eliminate them from solution.
Overall, compared to conventional methods of treating wastewater involving physical and biological processes, electrocoagulation water treatment system is generally considered far more effective in removing pollutant. Not only that, it is also compact and space-saving and while there are arguments in terms of cost calculation, but however, to most experts’ opinion, it is actually cheaper to maintain in the long run.
Electro coagulation process (using iron electrodes) is a reliable, efficient and cost- effective method. quickest removal rate with the lowest cost.
Before start up EC PROCESS the operator must check EC input effluent PH ,it should be always greater than 6.5 and less than 8.5.
EC operates at PH 6.5 TO 8.5 .
Every day before start up, EC the operator must clean EC skid with HCl. The operator should maintain the PH of the diluted Acid as less than 2.0. If the cleaning acid PH greater than 2.0, must drain old acid(high PH acid > 2.0) and fill new hydro choleric acid and clean EC skid.
Every day The operator’s every one hour once give air circulation in to EC SKID .
Before start EC skid the operator must prepare poly electrolyte dosing chemical.
The operator must dose poly electrolyte 2 to 2.5 ppm in EC outlet water.
Every day The operator always take chemical stock list and material stock list (EC PLATES ).
If EC plant stop, the operator must drain EC skid water and well rinse EC SKID with treated water .
Every day the operators note EC voltage and current value and record it separate log sheet.
The operator every one hours once check EC TREATED WATER QUALITY. if water quality is not good increase current value and set correct current value. IF treated water more green color present reduced EC skid current value and set correct current value.
Every day once the operator must prepare poly electrocoagulation water treatment system dosing. Normally 5 to 7 days once the operators must change used cleaning acid or Acid PH greater than 2.0 change the cleaning acid. When EC PLATE changing period the operator must note EC plates are sited in the mounding grid properly. It is very essential for any textile industry.