Anaerobic Dynamic Membrane Bioreactors (AnDMBRs): Are They an Efficient Way to Treat High-Strength Wastewater?

Abstract

This study assesses the impact of hydraulic retention time (HRT) on the performance of an anaerobic dynamic membrane bioreactor (AnDMBR) system using a carbon fabric membrane for treating high-strength wastewater. The evaluation of AnDMBR performance encompasses the removal of soluble chemical oxygen demand (sCOD), biogas/methane production, and membrane fouling. The average influent sCOD concentration was 11,814 +/- 1064 mg/L, with two HRT applications at 8 and 5 days and high biomass concentration (MLVSS 14,600 +/- 500 mg/L). An impressive sCOD removal efficiency exceeding 98% was achieved throughout the operation period. The AnDMBR system exhibited the highest biogas production, reaching 4.33 +/- 0.51 L/day, with a methane content of approximately 67.77 +/- 2.9% during the 5-day HRT stage. Transmembrane pressure (TMP) increased gradually at the 8-day HRT stage, leading to membrane fouling, whereas fouling occurred more rapidly at the 5-day HRT stage. Biomass analysis showed minimal variations in MLVSS, extracellular polymeric substance (EPS), and soluble microbial product (SMP) concentrations (protein and carbohydrate) across both HRT application stages. This study suggests that the AnDMBR system can be adopted effectively for treating high-strength wastewater, maintaining high COD removal efficiency and biogas production with 5-day HRT.