Optimization of Oil Palm Empty Fruit Bunch Fiber Composition as an Adsorption Unit in Palm Oil Mill Effluent Treatment

Abstract

The large volume of waste generated by the palm oil industry in Indonesia, consisting of approximately 23% Oil Palm Empty Fruit Bunches (OPEFB) and 65% Palm Oil Mill Effluent (POME), presents a significant environmental challenge. Waste reduction was conducted by integrating a physical process (adsorption using OPEFB) with a biological process (modified AnRBC) for POME treatment. The composition of OPEFB (spikelet and stalk) in the adsorption unit and the HRT in the AnRBC unit were varied. The 75:25 (spikelet:stalk) composition achieved the highest O&G removal efficiency (50.44%), while 25:75 showed the highest SCOD removal (8.09%). Kinetic modeling indicated that the Pseudo-First-Order (PFO) model outperformed other models, supported by higher Pearson correlation. Validation using actual effluent data confirmed its suitability, with Spearman’s Rho showing weak to strong correlations and ANOVA revealing no significant differences. The PFO model further demonstrated that the 75:25 composition had higher adsorption capacity (69.563 mg/g O&G; 223.335 mg/g SCOD), while the 25:75 composition had higher adsorption rates (0.219 1/d O&G; 0.008 1/d SCOD).