Effect of sludge pretreatment on the performance of anaerobic/anoxic/oxic membrane bioreactor treating domestic wastewater

• Published in: International journal of environmental science and technology (Tehran) Vol. 8; no. 2; pp. 281 - 290
• Main Authors: Rajesh Banu, J, Uan, D.K, Kaliappan, S, Yeom, I.T
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Center for Environment and Energy Research and Studies (CEERS) 01-03-2011; Springer-Verlag; Springer Nature B.V
• Subjects: Aquatic Pollution; Earth and Environmental Science; Ecotoxicology; Environment; Environmental Chemistry; Environmental Science and Engineering; Membrane bioreactor; Membrane reactors; Sludge; Sludge reduction; Soil Science & Conservation; Thermochemical pretreatment; Transmembrane pressure; Waste Water Technology; Water Management; Water Pollution Control; Water treatment; Sludge reduction; Membrane bioreactor; Thermochemical pretreatment; Transmembrane pressure
• ISSN: 1735-1472; 1735-2630
• DOI: 10.1007/BF03326216

In the present study, two bench-scale anaerobic/ anoxic/ oxic submerged
membrane bioreactors were used to study the effect of thermochemical
sludge disintegration system on the excess sludge production. Among the
two membrane bioreactors, one was named experimental membrane
bioreactor and another one was named as control membrane bioreactor,
where a part of the mixed liquor was treated with thermo chemical and
was returned back to membrane bioreactor. Thermo chemical digestion of
sludge was carried out at fixed pH (11) and temperature (75 °C)
for 24 % chemical oxygen demand solubilization. The other one was named
control membrane bioreactor and was used as control. The reactors were
operated at three different mixed liquor suspended solids range
starting from 7500 mg/L to 15000 mg/L. Both the membrane bioreactors
were operated at a flux of 17 LMH over a period of 240 days. The
designed flux was increased stepwise over a period of one week. During
the 240 days of reactor operation, both the membrane bioreactors
maintained relatively constant transmembrane pressure. The sludge
digestion had no impact on chemical oxygen demand removal efficiency of
the reactor. The results based on the study indicated that the proposed
process configuration has potential to reduce the excess sludge
production as well as it didn't detoriate the treated water quality.