Formulation and Evaluation of Alum: Cassava Peel Starch (CPS) Dual Coagulant System for Enhanced Turbidity Removal and Cost Efficiency in Water Treatment

Abstract

Clean water is becoming an urgent need due to increased pollution and exposure to the environment. The requirement for chemical coagulants to treat water rises in proportion to the level of impurities, leading to many setbacks that negatively impact day-to-day consumer use. Despite the fact that natural-based coagulants offer an environmentally friendly alternative, they do not perform better than conventional chemical coagulants. To surpass this limitation, the combination of chemical and natural coagulants has been proposed as a viable option. In this study, the effectiveness of Aluminium Sulphate (Alum), Cassava Peel Starch (CPS), and a dual coagulant system (Alum:CPS) in improving turbidity removal is explored. The objectives are to (i) compare the turbidity removal efficiency of chemical and dual coagulants, (ii) determine the optimum coagulant dosage through the Jar Test, and (iii) conduct the cost-benefit analysis of the coagulant systems. Sungai Penchala water samples were analyzed based on Malaysia’s National Water Quality Standards (NWQS) in considering selected parameters for the coagulants effectiveness evaluation. The Jar Test was employed to compare the turbidity removal efficiency of Alum, CPS, and Alum:CPS. Results indicated that the optimal doses of Alum, CPS, and Alum:CPS were 25 mg/L, 100 mg/L, and 80%:20% (20 mg/L:20 mg/L), respectively. The highest turbidity removal efficiencies achieved were 80.22% for Alum, 54.25% for CPS, and 91.25% for the dual coagulant system. The Alum:CPS combination exhibited improved turbidity reduction compared to individual coagulants. Furthermore, in the water treatment plant being studied, Alum:CPS exhibited both higher cost and maximum effectiveness, leading to 1.2 times greater cost-benefit ratio than Alum alone. These findings suggest that dual coagulant systems represent an effective approach to enhancing water treatment efficiency without compromising economic viability.