Fuzzy optimization of electrocoagulation for oil and grease removal from palm oil mill effluent

Palm oil mill effluent (POME) is produced in significant volumes in milling operations. Its elevated levels of oil and grease endanger the environment. Various treatment technologies have been established. Most fall short in providing a method with balanced efficiency and cost-effectiveness. A viable treatment approach is electrocoagulation (EC). The optimization of its variables can lower operational costs while maximizing performance. Limited studies evaluate the removal of oil and grease from POME. Few address cost in relation to variable optimization. A multi-objective fuzzy optimization model was utilized in this study. Voltage, electrolysis time, and electrolyte amount were treated as operating parameters within a multi-objective fuzzy optimization framework. Pareto optimal solutions were derived by applying the ε-constraint method. The fuzzy optimum was determined using a max-min operator. Optimization achieved 97.54 % removal of oil and grease for 0.27 USD/g-oil and grease removed with 86.80 % satisfaction. These were obtained under 17.55 V, 2.08 h of electrolysis, and 14.10 g L −1 amount of electrolyte. The results presented fuzzy optimization as a reliable framework for determining optimal operating conditions and established EC as a sustainable treatment technology for oil and grease in POME.