Application of salt extracted peanut seeds in the pretreatment of palm oil mill effluent (POME)

Abstract

This paper presents a study on the effectiveness of salt extracted peanut seeds after oil extraction as a novel coagulant for turbidity, total suspended solids (TSS) and chemical oxygen demand (COD) removal in palm oil mill effluent (POME) pretreatment process. The coagulation activity was investigated for the peanuts seeds after its oil extraction. The active coagulation component was extracted using three different concentrations of sodium chloride (NaCl), namely 0, 1 and 2 mol/l. The initial turbidity, TSS and COD of POME were found to be 11,684 NTU, 22,784 and 63,955 mg/l, respectively. The results show that extraction of coagulation active component from peanut seeds using NaCl improved the removal efficiency of the tested constituents. Accordingly, the higher NaCl concentration resulted in a low optimum dosage of peanut seeds and higher removal of turbidity, TSS and COD. Peanut seeds extracted with 2 mol/l reduced TSS to 1,218 mg/l (94.7% removal). On the other hand, peanut seeds extracted with distilled water (0 mol/l) reduced TSS to 2,175 mg/l (90% removal). Analysis of the present results and their comparison with the literature indicate that the coagulation activity of the peanut cake could be due to its protein component.