Anaerobic baffled reactor coupled with membrane bioreactor treating tannery wastewater

Abstract

Tannery wastewater contains high levels of the organic, inorganic, nitrogenous compound, suspended solids, dissolved solids, and other contaminants (Sulfide, chromium). Anaerobic Baffled Reactor-Membrane Bioreactor (ABR-MBR) system has been introduced as a promising technology for domestic wastewater treatment thanks to its sufficient organic treatment and low energy requirement. This work aimed to evaluate the performance and fouling behavior of the ABR-MBR system for tannery wastewater treatment during 60 d of operation. The ABR system was operated at an organic loading rate (OLR) of 3 kgCOD/m3. d while a low flux of 0.75 LMH was retained in the MBR. The results showed that the total COD removal was 89 ± 1% while the NH4+- N removal ranged from 28 to 33%. The fouling rate of MBR was from 5.14 to 6.18 kPa/d. The fouling degree became severe and this fact could be due to some matters: i) wastewater containing high salinity concentration (around 14,600 mg/L), ii) operation at high MLSS in MBR (over 10,000 mg/L), iii) and a short period of aeration time (1–3 min run: 7–9 min relaxation). Overall findings highlighted that the proposed ABR-MBR process could favor minimizing organic matter significantly.

Keywords

• Anaerobic baffled reactor
• Membrane filtration
• Tannery wastewater
• Membrane fouling