Fly ash is a by-product of coal combustion in thermal power plants which is classified as hazardous waste and a serious threat to environment. The study was conducted to determine the potential and examine the efficacy of electro kinetic technique (EKT) using variables like pH, total dissolved solids (TDS), e concentration of chlorides (Cl-), sodium (Na+),magnesium (Mg2+), potassium (K+), ammonia (NH3+) and calcium (Ca2+) on fly ash as a low-cost treatment for enhancing the use of fly ash in a more sustainable manner. The probability of removing heavy metals and chlorides from fly ash suspended in water using electro dialysis was studied as they are highly dependent on pH and conductivity of the fly ash. The voltage gradient and duration indicated significant effect in the change of pH values showing a range from 4.6 to 7.7 at cathode and anode respectively, while the Total dissolves solids (TDS) varying from 72.33±5.6 to 146±5.4 showed the enhanced availability of ions post electro dialysis. In terms of chlorides, Cl- the content was observed to be 265.06 mg/l which was high enough to cause corrosion problems in later stages of reuse of fly ash. The concentration of cations like Na+, K+, NH3+, Mg2+, Ca2+ were observed to be notably influenced by the duration of study and pH in electro dialysis. The experimental results of the study showed that the proposed technique based on the fundamentals of electro kinetics and dialysis could efficiently improve the remediation process which would remove metals by converting them to available form in fly ash.
Electro kinetics, Electro migration, Fly ash, Redox reaction, Total Dissolved Solids
Lima, A. T., Ottosen, L. M., and Ribeiro, A. B. (2012). Assessing fly ash treatment: Remediation and stabilization of heavy metals. Journal of Environmental Management, 95: S110-S115.
Ferreira, C., Ribeiro, A., and Ottosen, L. (2003). Possible applications for municipal solid waste fly ash. Journal of hazardous materials, 96(2-3): 201-216.
Pedersen, A. J., Ottosen, L. M., and Villumsen, A. (2005). Electro dialytic removal of heavy metals from municipal solid waste incineration fly ash using ammonium citrate as assisting agent. Journal of Hazardous Materials,122(1-2): 103-109.
Ottosen, L. M., Lima, A. T., Pedersen, A. J., and Ribeiro, A. B. (2006). Electro dialytic extraction of Cu, Pb and Cl from municipal solid waste incineration fly ash suspended in water. Journal of Chemical Technology and Biotechnology: International Research in Process, Environmental and Clean Technology, 81(4): 553-559.
Lima, A. T., Ottosen, L. M. and Ribeiro, A. B. (2009). Electro remediation of straw and co-combustion ash under acidic conditions. Journal of Hazardous Materials, 161(2-3): 1003-1009.
Acar, Y. B., and Alshawabkeh, A. N. (1996). Electro kinetic remediation. I: pilot-scale tests with lead-spiked kaolinite. Journal of Geotechnical Engineering, 122(3): 173-185.
Puppala, S. K., Alshawabkeh, A. N., Acar, Y. B., Gale, R. J., and Bricka, M. (1997). Enhanced electro kinetic remediation of high sorption capacity soil. Journal of Hazardous Materials, 55(1-3): 203-220.
Hansen, L. (2000). Treatment of aqueous solutions polluted with heavy metals in connection with electro dialytic soil remediation (Doctoral dissertation, Ph. D. thesis, Techncial University of Denmark, Denmark).
Mahzuz, H. M. A., and Hasan, M. J. (2020). Compressive strength enhancement of concrete using fly ash as a partial replacement of fine aggregate and model development. International Journal of Materials and Structural Integrity, 14(1): 44-53.
Gupta, V., Pathak, D. K., Siddique, S., Kumar, R. and Chaudhary, S. (2020). Study on the mineral phase characteristics of various Indian biomass and coal fly ash for its use in masonry construction products. Construction and Building Materials, 235: 117413.
Huang, T., Li, D., Kexiang, L., and Zhang, Y. (2015). Heavy metal removal from MSWI fly ash by electro kinetic remediation coupled with a permeable activated charcoal reactive barrier. Scientific Reports, 5: 15412.
Ribeiro, A. B., Rodriguez-Maroto, J. M., Mateus, E. P., Velizarova, E., and Ottosen, L. M. (2007). Modelling of electro dialytic and dialytic removal of Cr, Cu and As from CCA-treated wood chips. Chemosphere, 66(9): 1716-1726.
He, X., Yao, B., Xia, Y., Huang, H., Gan, Y., and Zhang, W. (2020). Coal fly ash derived zeolite for highly efficient removal of Ni2+ in waste water. Powder Technology, 367: 40-46.
Elicker, C., Sanches Filho, P. J., and Castagno, K. R. L. (2014). Electro remediation of heavy metals in sewage sludge. Brazilian Journal of Chemical Engineering, 31(2): 365-371.
Meer, I. and Nazir, R. (2018). Removal techniques for heavy metals from fly ash. Journal of Material Cycles and Waste Management, 20(2): 703-722.
Ferreira, C., Jensen, P., Ottosen, L., and Ribeiro, A. (2005). Removal of selected heavy metals from MSW fly ash by the electro dialytic process. Engineering Geology, 77(3-4): 339-347.
Pereira, C. M., Neiverth, C. A., Maeda, S., Guiotoku, M., and Franciscon, L. (2011). Complexometric titration with potentiometric indicator to determination of calcium and magnesium in soil extracts¹. Revista Brasileira de Ciência do Solo, 35(4): 1331-1336.
Weibel, G., Eggenberger, U., Kulik, D. A., Hummel, W., Schlumberger, S., Klink, W., ... and Mäder, U. K. (2018). Extraction of heavy metals from MSWI fly ash using hydrochloric acid and sodium chloride solution. Waste Management, 76, 457-471.
Kim, K. J., Cho, J. M., Baek, K., Yang, J. S., and Ko, S. H. (2010). Electro kinetic removal of chloride and sodium from tidelands. Journal of applied electrochemistry, 40(6), 1139-1144.
Rutigliano, L., Fino, D., Saracco, G., Specchia, V., & Spinelli, P. (2008). Electro kinetic remediation of soils contaminated with heavy metals. Journal of Applied ElectroChemistry, 38(7): 1035-1041.
Matsumoto, N., Uemoto, H., & Saiki, H. (2007). Case study of electrochemical metal removal from actual sediment, sludge, sewage and scallop organs and subsequent pH adjustment of sediment for agricultural use. Water Research, 41(12): 2541-2550.
Zayas, T., Rómero, V., Salgado, L., Meraz, M., & Morales, U. (2007). Applicability of coagulation/flocculation and electrochemical processes to the purification of biologically treated vinasse effluent. Separation and Purification Technology, 57(2): 270-276.
This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.
This work is licensed under Attribution-NonCommercial 4.0 International (CC BY-NC 4.0) © Author (s)