Investigation of PO43- Removal in Aerated and Unaerated High Fe EAF-Slag Filter System
Keywords:Adsorption, PO43- removal, adsorption, electric arc furnace slag, pH, rock filters.
AbstractPhosphorus in wastewater is one the main culprit which accelerates eutrophication in waterbody if it is not being treated properly. Steel slag filter emerged as one alternative treatment for wastewater. However, the variousness of metal oxides including Fe in steel slag will affect the phosphorus removal efficiency. Thus, this study was conducted to investigate the ability of a series of lab-scale high Fe electric arc furnace (EAF- slag) column filters in removing PO43- from synthetic wastewater. The systems were operated under aerated and unaerated within acidic and alkaline conditions. Synthetic wastewater contained 25 mg/L was prepared as the feed and monitored weekly basis for the PO43- removal efficiency and the total metals (Ca, Fe, and Mg) concentrations in the effluents. The results show that both aerated and unaerated high Fe EAF-slag filter systems have high PO43- removal efficiency under acidic condition, which unaerated system performed slightly better. It can be observed that unaerated systems performed better in removing PO43- at acidic and neutral pH values but not at extremely high pH. As for the PO43- removal mechanism was achieved by adsorption and precipitation at acidic pH and the concentration of Ca, Mg and Fe in effluents was related to the PO43- removal efficiency at different pH values.
 Ansari, A. A., & Gill, S. S. (2014) Eutrophication: Causes, consequences and control: Volume 2. 1â€“262.
 Johansson-Westholm, L. 2006. Substrates for Phosphorus Removalâ€“potential Benefits for On-site Wastewater Treatement?. Water Resources. 40: 23-36.
 Barca, C., Meyer, D., Liira, M., Drissen, P., Coemau, Y., Andres, Y., Chazarenc, F. 2014. Steel Slag Filters to Upgrade Phosphorus Removal in Wastewater Treatment Plants: Removal Mechanisms and Performance. Ecological Engineering. 68: 214-222.
 Barca, C., Troesch, S., Meyer, D., Drissen, P., Andres, Y., Chazarenc, F. 2013. Steel Slag Filters to Upgrade Phosphorus Removal in Constructed Wetlands: Two Years of Field Experiments. Environmental Science Technology. 47: 549-556.
 Hamdan, R., Mara, D. 2013. Study of In-filter Phosphorus Removal Mechanisms in an Aerated Blast Furnace Slag. International Journal of Research in Engineering and Technology. 2(8); 130-136.
 Scholz, M. (2006). Wetland systems to control urban runoff. Elsevier, Oxford,UK.
 Gerardi, M.H. (2006). Wastewater bacteria. John Wiley and Sons, Inc., New York.
 Han, C., Wang, Z., Yang, W., Wu, Q., Yang, H., Xue, X. 2016. Effects of pH on Phosphorus Removal Capacities of Basic Oxygen Furnace Slag. Ecological Engineering. 89:1-6.
 Wifert, P., Kumar, P. S., Korving, L., Witkamp, G., Loosdrecht, M.C.M. 2015. The Relevance of Phosphorus and Iron Chemistry to the Recovery of Phosphorus from Wastewater: A Review. Environmental Science and Technology. 49: 99400-9414.
 Xue, Y., Hou, H., Zhu, S. 2009. Characteristics and Mechanisms of Phosphate Adsorption onto Basic Oxygen Furnace Slag. Journal of Hazardous Materials.162: 973-980.
 Vohla,C., Koiv, M., Bavor, H. J., Chazarenc,F., Mander, U. 2011. Filter Materials for Phosphorus Removal from Wastewater in Treatment Wetlands- A Review. Ecological Engineering. 37: 70-89.
 Bowden, L. I., Jarvis, A. P., Younger, P. L., Johnson, K. L. 2009. Phosphorus Removal from Waste Waters Using Basic Oxygen Steel Slag. Environmental Science Technology. 43: 2476-2481.
 Zhong, B., Stanforth, R., Wu, S. Chen, J. P. 2007. Proton Interaction in Phosphate Adsorption onto Goethite. Journal of Colloidal Interfacial Science. 308: 40-48.
 Weng, L., Van Riemsdijk, W. H., Hiemstra, T. 2012. Factors Controlling Phosphate Interaction with Iron Oxides. Journal of Environmental Quality. 41: 628-635.
 Klimeski, A., Chardon, W. J., Turtola, E., Uusitola, R. 2012. Potential and Limitations of Phosphate Retention Media in Water Protection: A Process-based Review of Laboratory and Field-scale Tests. Agricultural and Food Science. 21: 206-223.