Target of 95% Recovery in NEWater Production by using CDI based Process for RO Brine Treatment
In Singapore, NEWater is the product of a multiple barrier water reclamation process from secondary treated domestic effluent using MF/UF-RO and UV technologies. More than 20% brine is generated from the RO process. To increase the water recovery and treat the RO brine, a Capacitive Deionization (CDI) process with biological activated carbon (BAC) as pre-treatment was developed and tested with the treatment capacity up to 5,000 L d-1. The results show that ion concentrations in CDI product were quite low except SiO2. RO permeate (CDI product as feed) was of good quality including low SiO2 comparing with NEWater. It could be beneficial to use a dedicated RO operated at optimum conditions with better performance to recover the water. It was observed that the type of pre-treatment, the feed water chemistry and the cleaning technique and chemicals played important role in the sustainable operation. Enhanced pre-treatment and lowering pH could minimize the fouling. The CDI pressure increased faster with high TOC feed. BAC was able to achieve 15–27% TOC removal of RO brine; about 40% of TOC removal could be achieved when combined with membrane filtration. To control the organic fouling of CDI cells, 60% TOC removal could be the setting point for activated carbon regeneration or replacement. CDI had a water recovery of at least 80%, so CDI based RO brine treatment could improve overall water recovery of NEWater production over 90%. The CDI cells had energy consumption about 0.7 kwh m-3. It was found that organic fouling was the major cause of CDI pressure increase. Sustainable operation especially organic fouling control and effective cleaning is being investigated.
No Reference information available - sign in for access.
No Citation information available - sign in for access.
No Supplementary Data.
No Article Media
Document Type: Research Article
Publication date: 2009-01-01
More about this publication?
- Proceedings of the Water Environment Federation is an archive of papers published in the proceedings of the annual Water Environment Federation® Technical Exhibition and Conference (WEFTEC® ) and specialty conferences held since the year 2000. These proceedings are not peer reviewed. A subscription to the Proceedings of the Water Environment Federation includes access to most papers presented at the annual WEF Technical Exhibition and Conference (WEFTEC) and other conferences held since 2000. Subscription access begins 12 months after the event and is valid for 12 months from month of purchase. A subscription to the Proceedings of the Water Environment Federation is included in Water Environment Federation (WEF) membership.
WEF Members: Sign in (right panel) with your IngentaConnect user name and password to receive complimentary access. Access begins 12 months after the conference or event
- Subscribe to this Title
- Membership Information
- About WEF Proceedings
- WEFTEC Conference Information
- Learn about the many other WEF member benefits and join today
- Ingenta Connect is not responsible for the content or availability of external websites