The Chemically enhanced process is considered to be a physicochemical technology for domestic wastewater treatment. The objective of this paper is to improve the efficiency of primary treatment processes and reducing the Hazardous Material and cost of the secondary treatment stage either by eliminating a biological treatment, where conditions and standards allow or by reducing the secondary treatment requirements. Analysis of physicochemical parameters as well as the treatment efficiency of aluminum sulfate (alum), ferric chloride (FeCl3), lime (CaO), and seawater was used. The effect of pH and the coagulant dosages were studied as well as mixing and settling time. Conditions were optimized according to the removal efficiencies measured in terms of reduction in the concentration of total suspended solids (TSS), biological oxygen demand (BOD5), and chemical oxygen demand (COD). The optimum COD removal % was achieved at a settling time of 20 minutes, while at pH~6, alum gave a high turbidity % removal of approximately 90% at the dose of 70 mg/l. FeCl3 gave a high turbidity % removal of approximately 95% at the dose of 40 mg/l. Turbidity removal and TSS removal gave a similar pattern at a settling time of 10-20 minutes, where best results were achieved. The results also showed that at pH~4, FeCl3 gave high COD% removal of approximately 90% at the dose of 40 mg/l. By studying the effect of stirrers’ speed (rpm), the results showed that an increase in the mixing intensity, above 80 rpm decreases the removals of COD, Turbidity and TSS when using alum as a coagulant.
Ji, J., Qiu, J., Wai, N., Wong, F., & Li, Y. (2010). Influence of organic and inorganic flocculants on physical–chemical properties of biomass and membrane-fouling rate. Water Research, 44(5), 1627-1635. doi: 10.1016/j.watres.2009.11.013
Wang, C., Dai, J., Shang, C., & Chen, G. (2013). Removal of aqueous fullerene nC60 from wastewater by alum-enhanced primary treatment. Separation and Purification Technology, 116, 61-66. doi: 10.1016/j.seppur.2013.05.035
Sahu, O., & Chaudhari, P. (2013). Review on Chemical treatment of Industrial Waste Water. Journal of Applied Sciences and Environmental Management, 17(2). doi:10.4314/jasem.v17i2.8
Lin, L., Li, R., Yang, Z., & Li, X. (2017). Effect of coagulant on acidogenic fermentation of sludge from enhanced primary sedimentation for resource recovery: Comparison between FeCl 3 and PACl. Chemical Engineering Journal, 325, 681-689. doi:10.1016/j.cej.2017.05.130
Ayoub, M., Afify, H., & Abdelfattah, A. (2017). Chemically enhanced primary treatment of sewage using the recovered alum from water treatment sludge in a model of hydraulic clari-flocculator. Journal of Water Process Engineering, 19, 133-138. doi:10.1016/j.jwpe.2017.07.014
Chakraborty, D., Karthikeyan, O. P., Selvam, A., & Wong, J. W. (2018). Co-digestion of food waste and chemically enhanced primary treated sludge in a continuous stirred tank reactor. Biomass and Bioenergy, 111, 232-240. doi:10.1016/j.biombioe.2017.06.002
Mosquera, M. (2014). Chemical precipitation and treatment control parameters in wastewater treatment: University of Stavanger, Norway.
Bratby, J. (2006). Coagulation and Flocculation in Water and Wastewater Treatment. IWA Publishing.
Mahmoud, E. K. (2013). Application of cement kiln dust for chemically enhanced primary treatment of municipal wastewater. Desalination and Water Treatment, 52(25-27), 4698-4704. doi:10.1080/19443994.2013.810384
Mouri, G., Takizawa, S., Fukushi, K., & Oki, T. (2013). Estimation of the effects of chemically-enhanced treatment of urban sewage system based on life-cycle management. Sustainable Cities and Society, 9, 23-31. doi:10.1016/j.scs.2013.02.003
Zhao, Q., Zhong, H., Wang, K., Wei, L., Liu, J., & Liu, Y. (2013). Removal and transformation of organic matters in domestic wastewater during lab-scale chemically enhanced primary treatment and a trickling filter treatment. Journal of Environmental Sciences, 25(1), 59-68. doi:10.1016/s1001-0742(12)60039-4
Pasqualino, J. C., Meneses, M., Abella, M., & Castells, F. (2009). LCA as a Decision Support Tool for the Environmental Improvement of the Operation of a Municipal Wastewater Treatment Plant. Environmental Science & Technology, 43(9), 3300-3307. doi:10.1021/es802056r
He, Q., Wang, H., Xu, C., Zhang, J., Zhang, W., Zou, Z., & Yang, K. (2016). Feasibility and optimization of wastewater treatment by chemically enhanced primary treatment (CEPT): a case study of Huangshi. Chemical Speciation & Bioavailability, 28(1-4), 209-215. doi:10.1080/09542299.2016.1247657
Hahn, M. J., & Figueroa, L. A. (2015). Pilot scale application of anaerobic baffled reactor for biologically enhanced primary treatment of raw municipal wastewater. Water Research, 87, 494-502. doi:10.1016/j.watres.2015.09.027
Mbamba, C. K., Lindblom, E., Flores-Alsina, X., Tait, S., Anderson, S., Saagi, R., Jeppsson, U. (2019). Plant-wide model-based analysis of iron dosage strategies for chemical phosphorus removal in wastewater treatment systems. Water Research. doi:10.1016/j.watres.2019.01.048
Mona A Abdel-Fatah, Marwa M Elsayed, Gh A Al Bazedi, S I Hawash (2016). Sewage Water Treatment Plant Using Diffused Air System. Journal of Engineering and Applied Sciences, Vol. 11(17): pp 10501-10506.
This work is licensed under a Creative Commons Attribution 4.0 International License.
The names and email addresses entered in this journal site will be used exclusively for the stated purposes of this journal and will not be made available for any other purpose or to any other party.
Submission of the manuscript represents that the manuscript has not been published previously and is not considered for publication elsewhere.