Evaluating Fertilizer-Drawn Forward Osmosis Performance in Treating Anaerobic Palm Oil Mill Effluent

Abstract

Fertilizer-drawn forward osmosis (FDFO) is a potential alternative to recover and reuse water and nutrients from agricultural wastewater, such as palm oil mill effluent that consists of 95% water and is rich in nutrients. This study investigated the potential of commercial fertilizers as draw solution (DS) in FDFO to treat anaerobic palm oil mill effluent (An-POME). The process parameters affecting FO were studied and optimized, which were then applied to fertilizer selection based on FO performance and fouling propensity. Six commonly used fertilizers were screened and assessed in terms of pure water flux (Jw) and reverse salt flux (JS). Ammonium sulfate ((NH4)2SO4), mono-ammonium phosphate (MAP), and potassium chloride (KCl) were further evaluated with An-POME. MAP showed the best performance against An-POME, with a high average water flux, low flux decline, the highest performance ratio (PR), and highest water recovery of 5.9% for a 4-h operation. In a 24-h fouling run, the average flux decline and water recovered were 84% and 15%, respectively. Both hydraulic flushing and osmotic backwashing cleaning were able to effectively restore the water flux. The results demonstrated that FDFO using commercial fertilizers has the potential for the treatment of An-POME for water recovery. Nevertheless, further investigation is needed to address challenges such as JS and the dilution factor of DS for direct use of fertigation.

Effects of Critical Operation and Cleaning Parameters on Performances and Economic Benefits of Biogas Slurry Concentration by Forward Osmosis Membrane

“…In addition, in the process of biogas slurry concentration, the fouling of the FO membrane will reduce its concentration efficiency. Herein, recovery of the FO membrane with simple method is beneficial to reduce the cost of FO technology for biogas slurry concentration [ 14 ]. The filtration efficiency of the entire FO membrane system can be improved by optimizing the operating parameters; the membrane flux of the fouled membrane can be restored by membrane cleaning and prolonging the service life of the membrane [ 15 ].…”