One of the technical visits will be to the Chennai/Koyambedu Water Reclamation Plant, a 40,000 m3/day (RO permeate) multiple barrier facility, which supplies highly purified reclaimed water to different industrial clients such as the automotive industry.
The plant is considered to be part of the critical infrastructure, as it helps to both save freshwater sources and secure the industrial water supply. It has been operated successfully by the Chennai- based WABAG company since the end of last year and even during the current Covid-19 crisis (since March), the supply of high-quality water to industry has been maintained without interruption.
Chennai/Koyambedu Water Reclamation Plant - Capacity: 40,000 m3/d highly purified reclaimed water for industrial purposes.
The process consists of pre-treatment with chlorine dioxide dosing (pre-disinfection and pre-oxidation in the equalization tank) and dual media rapid gravity filtration, polishing by basket strainers (50 µm), ultrafiltration, cartridge filtration (5 µm), reverse osmosis and ozone (O3) disinfection of the RO permeate. The major design parameters/standards are the TDS and silica concentrations, which amount to 1,500 mg/L and 40 mg/L respectively in the source water (secondary effluent from the Koyambedu Sewage Treatment Plant), and 70 mg/L and 5 mg/L respectively in the RO permeate (reclaimed product water).
Technical Visit 2
Indirect Potable Reuse Pilot Facility
Based on a detailed study, design and engineering approval by IIT Madras, Chennai Metropolitan Water Supply and Sewerage Board (CMWSSB) has established a Tertiary Treatment plant with 10 MLD capacity at Nesapakkam. The plant consists of a secondary treatment stage based on SBR followed by three stages of physical filtration including ultrafiltration membranes. The tertiary treatment involves three stages of disinfection with pre-chlorination, UV and advanced oxidation with ozone treatment. The purified recycled water is blended with Porur Lake water, which is used for drinking water production in a treatment plant consisting of coagulation/flocculation, DAF, multi-grade filtration, activated carbon filtration and disinfection by chlorine).
Simplified Pilot Plant Process Flow Diagram
Pilot Plant – Arial View
Multi Grade Filters
Bio-Monitoring
Augmentation of Lake Water with Purified Recycled Water