The Effectiveness of Electrocoagulation Process for the Removal of Cadmium from Water

Document Type : Research Paper

Authors

1 Grad. M.Sc. Student of Civil and Environmental Eng., Tarbiat Modares University, Tehran

2 Assoc. Prof., Dept. of Eng., Tarbiat Modares University, Tehran

3 Prof. of Environmental Eng., Dept. of Eng., Tarbiat Modares University, Tehran

Abstract

The presence of toxic heavy metals in industrial wastewaters and its discharge into the sewage system is one of the most environmental problems. In this research, electrocoagulation method was used to remove cadmium as a toxic heavy metal from aqueous phase. The important parameters wich affect the removal of cadmium from wastewater such as the electrode type, area of the electrode, distance between electrodes, voltage, intial concentreation of cadmium and the pH were examined.  Six electrodes with aluminum and iron types were employed with the areas of 2352, 3360, 4200 cm2. The distance between electrodes  were chosen to be 1, 2, 3 cm, respectively. The experimental results indicated that optimum condition was obtained with high surface area of the electrodes of 4200, distance of 1cm, entrance power of 185, residence of time of 40 minutes and pH of enfluent of 10.25. Results showed that change in initial cadmium concentration reduced its removel.

Keywords


1- Mardan, S., Tofighi, H., and Ahmadzadeh S. (2008). Removal of heavy metals from industrial wastewater, Iran Smal Industries and Industrial Park Organization (ISIPO) Pub., Tehran. (In Persian)
2- Derk, P. (1999). Guide to electrochemical technology, Southampton University Electrosynthesis Company, Inc., Southampton.
3- Alloway, B.J., and Axres, D.C. (1997). Chemical principles of environmental pollution, Chapman & Hall, Inc. London.
4- Patter Som, J.W. (1985). Industrial wastewater treatment technology, 2nd Ed., Butter Worth Publishers, USA.
5- Comninellis, C. (1992). “Eletrochemical treatment of wastewater containing Phenol.” Process Safe Environmental Protection, 70(4), 219-224.
6- Vigo, F., Avalle, L., and Paz, M. (1983). “Disposal of vegetation water from olive oil mills, study of electrochemical oxidation.” Riv. Ital. Sostanze Grasse, 60 (3), 125-131. (in Italian)
7- Tunturin, P.J. (1996). “Electrochemical treatment of process wastewater containing colloidal particles.” International Chemical Engineering, 16 (2), 222-228.
8- Vlyssides, A., Gisrailides, C.J., Loizidous, M., Karvouni, G., and Mourafeti, V. (1997). “Electrochemical treatment of vinasse from beet molasses.” Water Science and Technology, 36 (2-3), 271-278.
9- Huang, G.G., and Shou, S.S. (2001). “Comparison of a novel electro-fenton method with fenton ,s reagent in treating a highly contaminated wastewater.” Water Science and Technology, 143 (2), 17-24.
10- Masters, G.M. (2005). Introduction to environmental enginereeng and science, 2nd Ed., Prentice- Hall of India, New Delhi.
11- Echenfelder, W.W., and Cecil, L.K. (2002) Applications of new concepts of physical-chmical wastwater treatment, TN: Pergamon Press, Inc., Vanderbilt University, Nashville.
12- Joneidi Jafari, A. (2004). “Simulataneous removal of copper and 2, D4- dichlorophenal from industrial water through combined photo electrochemical degredation.” J. of Environmental Studies, 33, 1-7. (In Persian)
13- Samarghandi, M.R., Zarabi, M., Safari, G., Shirzad, M., Gharibi, H., and Dheikh Mohammadi, A. (2009). “Study of electro-coagolation for phosphate removal from aqueous solution.” 12th Conf. of National  Environmental Health, Tehran, 18-27. (In Persian)
14- Rahmani, A., and Samarghandi, M.R. (2007). “Electrochemical removal of COD from effluents.” J. of Water and Wastewater, 64, 9-20. (In Persian)
15- Mollah, M., Morkovsky, P., Gomes, J., Kesmez, M., Parga, J., and Cocke, D. (2004). “Fundamentals, present and future perspectives of electrocoagulation.” J. of Hazardous Materials 114, 199-210.
16- Holt, P.K., Barton, G.W., and Mitchell, C.A. (2006). “The future for electrocoagulation as a localiced water treatment technology.” Chemosphere, 23 (2), 355-367.
17- Rich, L.G. (1999). Mixed – liquor recycle (MLR) Lagoon nitrification system, Technical Note Number 7, Department of Enviromental Engineering and Science, Clemsom University, USA.
18- Chen, G. (2004). “Electrochemical technologies in wastewater treatment.” Separation and Purification Technology, 38, 11-41.
19- Janssen, L.J.J., and Koene, L. (2002). “The role of electrochemistry and electrochemical technology in environmental protection.” Chemical Engineering, 85 (2-3), 137-146.
20- Bazrafshan, A., Mahvi, A.H., Mesdaghinia, A.R., Nasseri, S., and Vaezi, F. (2007). “Study of electro coagulation with Alumina electrodes for Cr removal.” 10th Conf. of Environmental Health, Hamedan, 35-38. (In Persian)