Abstract:
Ultrafiltration membranes technologies are finding increasing application in
disinfection process to improve water quality for drinking water production as a safety
and environmentally process. However the influence of water pH and bacterial
Escherichia Coli (E.coli) concentration limited the applicability of this technology
due to the fouling phenomena. The specific objectives for this study are to investigate
the effect and the optimum value of Escherichia Coli concentration and pH
parameters on the bacterium Escherichia Coli removal through the UF membrane. In
this study three different water pH6, pH7 and pH8 and bacterial E.coli concentration
log 105.1 cfu/ml, log105.7 cfu/ml and log 1o6 cfu/ml though to be in some extent
responsible for membranes fouling are evaluated. Ultrafiltration membrane with
difference composition made of polysulfone (PSF), N-metil-2-pyrolidone (NMP) and
polyvinylpyrolidone (PVP)-(13wt.%, 15wt.% and l 7wt.%) using an electrically
controlled casting machine are prepared. The membranes permeability and
performance of removing E.coli in different feed concentration and pH were
determined based on E.coli solution flux and rejection percentage. The ability
rejection of different feed concentration for each membrane shown that the lower the
bacterial solution concentration the higher the flux and bacterial rejection in the
following manners: (log105.l cfu/ml > log105.7 cfu/ml > log106 cfu/ml). The pH
adjustment could be used to control the UF fouling and bacterial rejection. The acid
pH will improve the UF performance, where this behavior is explained in term of
charge effects on membrane size. These finding suggested that the best membrane
composition is I3wt.%, with log105.l cfu/ml solution concentration with pH 6.
Besides, the higher percentage of bacterial E.coli rejection (7 log reduction value)
showed a great potential of applying UF membrane in water treatment plant.
