Comparison of fouling characteristics of two different poly-vinylidene fluoride microfiltration membranes in a pilot-scale drinking water treatment system using pre-coagulation/sedimentation, sand filtration, and chlorination.
Two pilot-scale hybrid water treatment systems using two different poly-vinylidene fluoride (PVDF) microfiltration (MF) membranes (i.e. symmetric and composite) were operated at a constant permeate flux of 104.2l m(-2)h(-1) (=2.5 md(-1)) with a pre-coagulation/sedimentation, sand filtration (SF), and chlorination to produce potable water from surface water. Turbidity was removed completely. And humic substances, Al, and Fe were removed very well by the pilot-scale membrane system. To control microbial growth and mitigate membrane fouling, a NaOCl solution was injected into the effluent from SF before reaching the two membranes (pre-chlorination). However, it adversely affected membrane fouling due to the oxidization and adsorption of inorganic substances such as Al, Fe, and Mn. In the next run, the NaOCl was introduced during backwash (post-chlorination). As compared with the result of pre-chlorination, this change increased the operating period of the symmetric and the composite membranes from about 10 and 50 days to about 60 and 200 days, respectively.
Chae
So-Ryong
SR
Department of Civil and Environmental Engineering, School of Engineering, Duke University, Durham, NC 27708, USA. srchae75@yahoo.co.kr
Yamamura
Hiroshi
H
Ikeda
Keiichi
K
Watanabe
Yoshimasa
Y
D002713:Chlorine / Q000737:chemistry*; D005374:Filtration / Q000295:instrumentation / Q000379:methods*; D008567:Membranes, Artificial; D010865:Pilot Projects; D011145:Polyvinyls / Q000737:chemistry*; D014881:Water Supply / Q000032:analysis*; D005465:Fluorocarbon Polymers
D002713:Chlorine; D008567:Membranes, Artificial; D011145:Polyvinyls; C024865:polyvinylidene fluoride; D005465:Fluorocarbon Polymers