Thesis - faculty.ait.ac.th - Asian Institute of Technology

Table 3.7 Characteristics of Ultrafiltration Membrane
UF Membrane Types MWCO (kDa)
Koch membrane, M-100 50
Koch membrane, K-131 10
Koch membrane, K-328 5
3.6.5 Sludge Characterization
The variation in sludge characteristics was estimated in both the reactors. The
YMBR and BMBR systems can be divided into three zones based on the membrane cycle.
Based on the membrane fouling, the sludge was sampled for analysis. Sludge properties
which were determined in both the reactors were the extra cellular polymer substances
(EPS), sludge volume index (SVI), capillary suction time (CST), MLSS and viscosity.
3.7 Ammonia Stripping Coupled Membrane Bioreactor
The membrane bioreactor was coupled with ammonia stripping to find out the
treatment efficiency of this combined treatment system. The experimental set-up consists
of two treatment systems, namely: ammonia stripping and membrane bioreactor (MBR) as
shown in Figure 3.5. Figure 3.7 show the procedure of the coupling ammonia stripping
with MBR.
The operating conditions for ammonia stripping process were based on the results
obtained from the previous experiment. Mean velocity gradient, pH and the mixing time
were based on the experimental results obtained after optimization of the ammonia
stripping conditions. The ammonia stripped leachate was used as a feed in both the YMBR
and BMBR reactors. The design of the reactors used for the experiment was similar to
bioreactor as described 3.6.2.
The HRT used in this experiment are from the results obtained after performing the
parametric studies as described in session 3.6.3. The excess sludge was periodically
withdrawn to maintain a mean biomass of 10,000 to 12,000 mg/L of MLSS. The bioreactor
was assessed in terms of the membrane performance in leachate treatment and sludge
characteristics.
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