A. Fakhru'L-razi et Mjmm. Noor, Treatment of palm oil mill effluent (POME) with the Membrane Anaerobic System (MAS), WATER SCI T, 39(10-11), 1999, pp. 159-163
One of the major difficulties in anaerobic wastewater treatment processes i
s the need to retain a sufficient quantity of active biomass in the anaerob
ic reactor. The use of membranes to achieve external solid/liquid phase sep
aration will result in the retention of the biomass at the surface of the m
embranes. In this study, the Membrane Anaerobic System (MAS) was used to tr
eat industrial wastewater from a palm oil mill. The MAS was subjected to in
creasing organic loading rates (OLR) and a total of six steady states were
attained. The first steady state influent COD concentration was 39,910 mg/l
increasing to the final or sixth steady state COD concentration of 68,310
mg/l. The efficiency of COD removal was between 91.7 to 94.2 percent with a
n average HRT of 3.03 days. The maximum OLR applied during the sixth steady
state was 21.7 kgCOD/m(3)/d. The reactor mixed liquor suspended solids (ML
SS) was between 50,000 to 57,000 mg/l while the percentage of the mixed liq
uor volatile suspended solids (MLVSS) was between 74 to 82 percent. A cross
flow ultrafiltration (UF) module was used to filter the final effluent and
simultaneously retain biomass in the anaerobic reactor. A clear final efflu
ent was produced but membrane flux rate deterioration was observed due to m
embrane fouling. Membrane fouling could be minimised with faster crossflow
feed velocities and regular membrane flushing. (C) 1999 Published by Elsevi
er Science Ltd on behalf of the IAWQ. All rights reserved.