New Approaches in Drinking Water and Wastewater Treatment Coagulation System: A Mini-Review

Turbidity and natural organic matters (NOMs) cause change in odor, color, and taste of drinking water as well as increasing the concern of bacterial growth in water and wastewater. This article aims to review the coagulation process and to introduce the potential approaches that can help the water and wastewater authorities to come up with the best coagulant selection. The coagulation is a physicochemical process that is used in the conventional treatment process to reduce turbidity, suspended particles, and NOMs. Aluminum sulfate (alum) and ferric chloride are the most common coagulants that are used as chemical coagulants. However, there are some health concerns associated with the residual sludge and extra dose of chemical coagulants in treated water and wastewater such as increasing risk of Alzheimer and cancer. Natural Coagulants could be an alternative to reduce the dose of chemical coagulants and residual sludge and consequently reducing the health risks. Natural coagulants are effective in reducing particles, alongside the chemical coagulants or as a stand-alone process. The multidimensional nature of choosing the best process in water and wastewater treatment makes it difficult to select the best coagulant with the minimum health risk. Therefore, we need a systematic framework for modeling the coagulation process and selecting cost-efficient coagulant(s) to reduce health risk. Mathematical modeling and health risk assessment are two of the approaches that can be used to select the optimum range and track the residual and found to be helpful for the health risk reduction