الفهرس 
Water reuse in EgyptOnly 14 pages are availabe for public view
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Abstract
In the present study, the use of submerged membrane
bioreactor (SMBR) for municipal wastewater reclamation
has been investigated. The most common configurations
namely; hollow fiber (HF) and flat sheet (FS) were used. To
develop optimum operating conditions, two bench-scale modules
were used; HF SMBR and FS SMBR. The systems were operated
and fed continuously with real wastewater from a near-by
municipal wastewater treatment facility.
The impact of changing the most influential operational
parameters such as hydraulic retention time (HRT), sludge
retention time (SRT) and organic loading rate (OLR) on the
performance of the two modules was the main focus of the
present study. The results obtained indicated that the two
modules could ensure a very good quality effluent, regardless of
the variations in raw wastewater strength and HRTs. Chemical
oxygen demand (COD) and biological oxygen demand (BOD)
removal rates above 90% were achieved. Residual suspended
solids were below detectable limits. The membranes trapped
significant proportions of the pathogenic organisms. At the same
time, HRT was found to be a key parameter for fouling.
Monitoring the Trans membrane pressure (TMP) indicated that
membrane fouling can be reduced by operating the HF SMBR at
low permeate flux or longer HRT. Changing the SRT from 30d
to 40d and then to 60d did not affect organic compounds removal in terms of COD and BOD removal. Also, complete nitrification
has been reported for the three tested SRTs. However, increasing
SRT has led to an increase in the rate of membrane fouling. Total
fouling resistance (RT) increased from 0.28 x 1013 to 0.4 x 1013
m-1d by increasing SRT from 30 to 60 d. Doubling the applied
OLR from 3.48 to 6.6 kg COD/m3d exerted negative impact on
the nitrification process.