Fouling Behavior in a High-Rate Anaerobic Submerged Membrane Bioreactor (AnMBR) for Palm Oil Mill Effluent (POME) Treatment

Abstract

The characteristics of foulant in the cake layer and bulk suspended solids of a 10 L submerged anaerobic membrane bioreactor (AnMBR) used for treatment of palm oil mill effluent (POME) were investigated in this study. Three different organic loading rates (OLRs) were applied with prolonged sludge retention time throughout a long operation time (270 days). The organic foulant was characterized by biomass concentration and concentration of extracellular polymeric substances (EPS). The thicknesses of the cake layer and foulant were analyzed by confocal laser scanning microscopy and Fourier transform infrared spectroscopy. The membrane morphology and inorganic elements were analyzed by field emission scanning electron microscope coupled with energy dispersive X-ray spectrometer. Roughness of membrane was analyzed by atomic force microscopy. The results showed that the formation and accumulation of protein EPS in the cake layer was the key contributor to most of the fouling. The transmembrane pressure evolution showed that attachment, adsorption, and entrapment of protein EPS occurred in the membrane pores. In addition, the hydrophilic charge of proteins and polysaccharides influenced the adsorption mechanism. The composition of the feed (including hydroxyl group and fatty acid compounds) and microbial metabolic products (protein) significantly affected membrane fouling in the high-rate operation.

Circular Economy Approaches in the Palm Oil Industry: Enhancing Profitability through Waste Reduction and Product Diversification

“…Anaerobic digestion technology has revolutionized the way palm oil mills manage POME, turning it into biogas and contributing to a more sustainable energy landscape [134,135]. The extraction of bioactive compounds from palm oil and its by-products has paved the way for the creation of high-value functional ingredients, while biobased chemicals and green cosmetics have emerged as sustainable alternatives in various industries [136][137][138][139][140][141].…”

Performance of a high rate two-stage anaerobic membrane bioreactor (AnMBR) for the treatment of palm oil mill effluent

“…1. It consisted of an anaerobic hydrolytic reactor (HR) and an anaerobic membrane bioreactor (AnMBR) made of polysulfone hollow fibers with a 0.025 m 2 area, which were fabricated as described in a previous study (Chaipetch et al 2021). The operational conditions are presented in Table 2.…”

“…The membrane filtration was operated under sub-critical and flux constant modes. To prevent fouling, the relaxing conditions and internal recirculation were set to be the same as the previous study (Chaipetch et al 2021). The fouling rate was determined by the ratio of flux obtained per transmembrane pressure.…”

Role of coagulation/flocculation as a pretreatment option to reduce colloidal/bio-colloidal fouling in tertiary filtration of textile wastewater: A review and future outlooks

“…Thus, in addition to the environmental impact of untreated textile industry wastewater, poorly treated effluents can affect the tertiary treatment efficiency of wastewater treatment plants (WWTPs) in terms of operational and resource costs. Particularly, these solids, organics, and bio-colloids (mostly high from the secondary effluent) in wastewater can impact tertiary filter techniques at the tertiary treatment stage, damaging them due to fouling (Chaipetch et al, 2021). Tertiary filters are the most preferable process to recover good-quality water, which feeds from secondary effluents, in wastewater treatment processes.…”