RTM-led process fixes lower STP operating costs and improve treatment reliability.
The clients are a gated community with 228 apartments located at Chennai. A 200 KLD Sewage Treatment Plant (STP) was operational there as the STP treated water was designed to be reused for toilet flushing and gardening. But the challenges in improving and maintaining the STP’S performance was leading to poor quality treated water and sky rocketing water charges.
Challenge
The quality of recycled water was poor due to improper sewage treatment process, leading to treatment efficiency of only 30%. The disinfection was improper and the final treated water was odorous. Issues with frequent equipment failure resulted in high operational cost. Other issues faced at site include excessive sludge due to the absence of a sludge drying bed at Site.
Solution
In August 2018, Greenvironment installed the RTM system, an Internet of Things based solution, to troubleshoot issues and improve STP performance at the site. Using real time data from the RTM system, Greenvironment analyzed key performance parameters and recommended process corrections. The team replaced the raw sewage transfer pump with a 5HP cutter pump instead of a 2HP submersible pump. This upgrade increased flow rates, reduced operating hours, and supported energy conservation. The team also modified the piping from the collection tank to the aeration tank to maintain the batch cycle within the required timeline. Greenvironment replaced the pressure sand filter and activated carbon filter media due to poor filtration and treated water discoloration. To improve filtration efficiency and extend media life, the team changed the backwash line from filter feed water to treated water. The team installed sludge drying beds to enable effective removal of excess sludge. The site now repurposes the dried sludge as fertilizer for landscaping. Greenvironment also implemented an automatic ORP based chlorine dosing system to achieve consistent and reliable disinfection. These process improvements now allow the STP to produce treated water suitable for toilet flushing and gardening reuse.
Outcome
The RTM has helped to reduce the operating cost of the STP from Rs 55/KL to Rs 30/KL because of higher efficiency of the plant.
Rs 40 Lakhs annual Saving on fresh water bill