Using Pseudomonas aeruginosa PAO1 to evaluate hydrogen peroxide as a biofouling control agent in membrane treatment systems.
Hydrogen peroxide (H2O2) is widely used in water treatment for biofouling control and, in conjunction with catalysts, as a powerful oxidant for contaminant destruction. H2O2could potentially serve as an antifouling agent in reverse osmosis systems in lieu of chlorine-based disinfectants. The dependence of the biocidal efficiency of H2O2on cell density, temperature and H2O2concentration by determining the growth, attachment and viability of the model bacterium Pseudomonas aeruginosa PAO1 was studied. For controlling growth of planktonic PAO1 cells, the minimally required H2O2concentration depends on the cell density and temperature. The effect of H2O2to remove the existing biofilm was found to be effective in the presence of a high concentration bicarbonate (8·4 g l-1), which forms peroxymonocarbonate, a strong oxidant and disinfectant. Treatment with H2O2-bicarbonate reduced the density of live PAO1 cells, removed extracellular polymeric substances and lowered the average biofilm thickness while maintaining the integrity of the membrane, suggesting that this type of treatment may be a suitable 'in-place-cleaning' procedure for biofouled membranes.


CONCLUSIONS
H2O2is evaluated as a potential replacement for chlorine to control biofouling in membrane-based water treatment systems. The biocidal efficacy of H2O2was evaluated as a function of H2O2concentration, cell density and temperature using the model organism Pseudomonas aeruginosa PAO1. Results demonstrated that at low temperatures and low cell densities, bacterial growth and membrane biofouling can be prevented by low H2O2concentrations, and existing biofilms could be removed by H2O2-bicarbonate mixtures. Findings suggested that H2O2could be used as a low cost agent for prevention and controlling biofouling in reverse osmosis applications.
Department of Civil and Environmental Engineering, National University of Singapore, Singapore, Singapore.
Y
Y
Yang
Division of Environmental Engineering, Hokkaido University, Sapporo, Japan.
M
M
Kitajima
Department of Civil and Environmental Engineering, National University of Singapore, Singapore, Singapore.
T P T
TP
Pham
Department of Civil and Environmental Engineering, National University of Singapore, Singapore, Singapore.
L
L
Yu
Department of Civil and Environmental Engineering, National University of Singapore, Singapore, Singapore.|NUS Environmental Research Institute, National University of Singapore, Singapore, Singapore.
R
R
Ling
Department of Civil and Environmental Engineering, National University of Singapore, Singapore, Singapore.|NUS Environmental Research Institute, National University of Singapore, Singapore, Singapore.
K Y H
KY
Gin
Department of Civil and Environmental Engineering, National University of Singapore, Singapore, Singapore.|Department of Civil and Environmental Engineering, Stanford University, Stanford, CA, USA.
M
M
Reinhard
D018441:Biofilms / Q000187:drug effects; D057219:Biofouling / Q000517:prevention & control*; D005618:Fresh Water / Q000382:microbiology; D006861:Hydrogen Peroxide / Q000494:pharmacology*; D008567:Membranes, Artificial; D011550:Pseudomonas aeruginosa / Q000187:drug effects* / Q000254:growth & development / Q000502:physiology; D018508:Water Purification / Q000379:methods*
D008567:Membranes, Artificial; D006861:Hydrogen Peroxide

Pseudomonas
; biocides; biofilms; disinfection; membrane