Removal of heavy metals and hardness from groundwater via electro-coagulation method

Document Type : Original Research Paper

Authors

1 PhD Candidate in Civil-Water Engineering, Iran University of Science & Technology, Iran

2 Associate Professor, Faculty of Environment, University of Tehran, Iran

3 MSc. Student of Civil Engineering-Environment, Aras International Campus, University of Tehran, Iran

Abstract

Groundwater makes up an important part of global freshwater resources, though it is often threatened by overuse of natural resources along with abundant production of wastes in modern society. This study aims to investigate the removal of three heavy metals including nickel, cadmium, and lead from groundwater via electrocoagulation, a suitable method for treatment of water-soluble compounds, dealing with the impact of this process on three major groundwater parameters, namely TDS (Total Dissolved Solid), TH, and EC at a laboratory scale. The experiments have been performed using four aluminum electrodes. In this research, the efficiency of contaminants removal and the parameters of interest have been investigated under several conditions such as the distance among the electrodes, potential difference among the electrodes, and different initial concentrations of heavy metals with a detention time of 20 min. Afterwards both results and observations have been analyzed, using diagrams and data tables. Results indicate that this method has had no significant effect on TDS and EC; however, in case of TH, the removal has increased by up to 29.17%. As for the heavy metals, all three contaminants have achieved an increase of the potential difference to 15 V, a decrease in the distance among the electrodes to 2.2 cm, as well as a removal of over 90%. Furthermore, result analysis shows that this process has had a better removal efficiency, concerning lead. 

Keywords


Akhundi, A., Khodadadi Darban, A. and Ganjidoost, H. (2012). Kadmium removal from aquatic ecosystems by electrocogulation. Water and Wastewater Journal, 8, 23-31.
Asghari Moghaddam, A. (2011). Principles of groundwater quality. Tabriz University.
Brad, M., Angel, Chad V., Jarolimek, Joshua J., King, Leigh T., Hales, Stuart L., Simpson, Robert F., Jung, Simon C. (2012). Metals in the Waters and Sediments of Port Curtis, Queensland (CSIRO).
Chen, G. (2004). Electrochemical technologies in wastewater treatment. Separation and Purification Technology, 38(1), 11-41.
Daneshvar, N. (2009). Water and industrial treatment chemistry. Amidi publication.
Diels, L., Geets, J., Dejonghe, W., Van Roy, S., Vanbroekhoven, K., Szewczyk, A. and Malina, G. (2006). Heavy Metal Immobilization In Groundwater By In Situ Bio precipitation: Comments And Questions About Efficiency And Sustainability Of The Process, Proceedings of the Annual International Conference on Soils, Sediments, Water and Energy, 11, 7-15.
Ghahremai, H. and Doustmohammadi, M. (2011). Upgrading milk process effluent plants by electro coagulation. First refinery conferences on environment. Sharif University of Technology, Iran.
Hassanzadeh, R., Abbass Nezhad, A. and Hamzeh, M. (2010).Evaluation of groundwater pollution, case study: Kerman city.Environmental Studies Journal, 36(56), 101-110.
Karbassi, M., Karbassi, E., Saremi, A. and Ghorbanzadeh, H. (2010). A mount of heavy metals in Alashtar portable water resources. Lorestan Medical Journal, 12, 65-70.
Khosravi, R. and Keshmirizadeh, E. (2011). Reviewing electro coagulation process efficiency for effluent treatment. Water and Wastewater International Conference, Tehran.
Lo, C.K. and Fung, Y.S. (1992). Heavy Metal Pollution Profiles of Dated Sediment Cores from Hebe Haven, Hong Kong,Water Res. 26, 1605-1619.
Malekutian, M. and Mohammadi Senjed Kooh, S. (2014). Sirjan plain groundwater pollution study. Torbat Heydariye Medical University Journal, 2(2), 31-39.
Pais, I.J. and Jones, B.J. (1997). The Hand Book of Trace Elements. St. Luice Press, N. W., Baca, Roton, Florida.
Pirsaheb, M., Khamutian, R. and Pourhaghighat, S.R. (2015). Review of Heavy Metal Concentrations in Iranian Water Resources. International Journal of Health and Life Sciences, 35-45.
Shahriyari, T. (2015).Impacts of lead existence in aquatic waters and its removal by electro coagulation. Environmental Studies, 3(41), 711-719.
Todd, D. and Mays, L. (2005). Groundwater hydrology, 3rd edition. Wiley publication.
Younes, B., Al-Meshari, A.A. and Al-Hakeem, A. (1995). Lead concentration in breast milk of nursing mothers living in Riyadh. Annals of Saudi Medicine, 15(3), 249-251.