Kim, S. L., J. Paul Chen, Y. P. Ting. WASTEWATER RECLAMATION: MEMBRANE OPERATION IN THE TREATMENT OF SECONDARY EFFLUENT
Department of Chemistry and Environmental Engineering, National University of Singapore, 10 Kent Ridge Crescent, Singapore, sg, 119260, Singapore (checjp@nus.edu.sg)
Membrane applications in wastewater reclamation are challenged by high fouling potential of secondary effluent used as feed. Feed pretreatment and membrane cleaning were studied as preventive measures against membrane fouling in wastewater reclamation application.
Three pretreatment systems were investigated for a reverse osmosis (RO) unit treating secondary effluent. They were (i) membrane ultrafiltration (UF), (ii) dual media filtration and granular activated carbon adsorption without and (iii) with addition of organic flocculant. Results showed that UF provided the best pretreatment for the RO unit amongst three pretreatment systems.
Physical and chemical membrane cleaning methods were studied and optimised using fractional factorial and techniques such as regression analysis and surface response contour plots. Results suggested that physical cleaning should be implemented for UF and RO every 30 min and 6 hr respectively. Efficiency of chemical cleaning was affected by temperature and concentration of high pH cleaning solution and backwash after chemical clean.