The effects on treatment efficiency of membrane modüle shapes, fiber ranges and biogas spargingi in the submerged anaerobic membrane bioreactor

MBRs are being increasingly used for wastewater treatment that requires excellent effluent quality, e.g., water reuse or water recycling. MBRs allow high concentrations of mixed liquor suspended solids (MLSS) and low production of excess sludge; enable high removal efficiency of biological oxygen demand (BOD) and chemical oxygen demand (COD), and water reclamation. In this thesis, the aim was to study the feasibility of submerged anaerobic membrane bioreactors (SAnMBRs) for synthetic wastewater treatment, quantifying the specific chemical parameters removal efficiency and biogas production. In addition reactor sludge properties and relations between membrane module shapes and biogas sparking were evaluated in submerged anaerobic bioreactor. Some parameters such as COD, solids, alkalinity, volatile fatty acids (VFA), total phosphorus (TP), total nitrogen (TN), and sulfate were measured periodically. Results of the analysis were indicated the of COD removal efficiency of permeate 95-98% with a value around 40-280 mg/l. During the operation the removal efficiencies of COD, SO4= , TOC were 95-98%, 15-70% and 96-98%, respectively. The removal efficiency of volatile suspended solids (VSS) was over 97-98%. A great rate of total suspended solids (VSS) was found to be included dissolved solid. It was found that optimum performance was with pH in the range of 6.3 and 8.45. Alkalinity and VFA values in the reactor were around 1500-3500 mg/L as CaCO3 and 80-180 mg HoAc/L, respectively. VFA/alkalinity ratio was below to 0.1 for all experimental conditions. A high COD removal efficiency was achieved, and the biogas which has a good quality performed. The during operation biomass concentrations were maintained in the range of 5.6-9.2 g/L. Results also show that the application of anaerobic membrane bioreactors is an efficient way to retain specific bacteria that can be a key factor for the treatment of wastewaters under mesophylic conditions. In this study, it was concluded that negligible effects of membrane geometric forms on removal efficiency. However , biogas sparging was slightly effective on performance of submerged anaerobic membrane bioreactors. Key words: Submerged anaerobic membrane bioreactor, wastewater treatment, biogas sparging, membrane geometry, methane production.