HYDERABAD: The Hyderabad Metropolitan Water Supply and Sewerage Board (HMWS&SB) has initiated what has come to be known as the “Circular Economy” by selling sludge, methane gas, and plastic waste generated from the STPs, and converting them into value-added products, besides finding a use for the treated water.
The Water Board aims to achieve the circular economy’s objectives which will help generate revenue for STPs. It has also planned to install screw turbines to generate hydel power and recycle plastic waste.
To take forward the circular economy initiatives, the Water Board has proposed to set up a “Circular Economy Cell ‘’ in the HMWS&SB head office at Khairatabad which will be headed by the Chief General Manager to expedite the implementation of CE. The CE is for recovering resources from wastewater, sludge, gas, and silt and creating new revenue streams by selling energy, water, and fertilisers to cover operating costs. Sources said that at present HMWS&SB is maintaining as many as 20 STPs with a total 714.3 MLD capacity installed at different locations in the city.
Further, another 31 STPs are taken up in Greater Hyderabad limits. On their completion, another 1259.50 MLD of treated wastewater will be available for reuse. HMWS&SB has proposed to engage an agency for marketing and distributing the treated wastewater to potential users to generate some revenues for the maintenance of the STPs.
About 70 tonnes of sludge is being generated at the existing 20 STPs. It is being handed over to the private agencies @ Rs 560/ MT. The agencies process this sludge and convert it into city compost and market it in collaboration with Rashtriya Chemicals and Fertilisers for agricultural purposes.
This activity has so far generated about Rs 63 lakh. Treated wastewater is supplied to WIPRO, NCC Ltd and other agencies for road works and also for gardening at Raj Bhavan, Shilparamam, Botanical Gardens and plantations on road medians by GHMC. The treated wastewater is being sold at Rs 12 per KL and an amount of Rs 20 lakh has already been realised.
Meanwhile, the Water Board has appointed M/s.NCPE as consultants for preparation of DPR for identification of potential users for reuse of treated wastewater in Hyderabad Urban Agglomeration (HUA). They have already submitted the draft DPR. The Board held an interactive session last month with potential users and stakeholders on the usage of treated wastewater for various purposes.
About 7000 cum/per day of methane gas is generated at Amberpet and Nagole STPs. A licenced agency has been engaged to process the raw gas and convert it into Compressed Biogas which will be supplied to HPCL/IOCL/BPCL/similar petroleum companies, for utilisation in automobiles. The agency is in the process of setting up the processing and bottling plant at STPs.
HMWS&SB has invited Expression of Interest (EoI) proposals to hire the agencies to recycle the silt generated at STPs and sewer lines and conversion into value-added products such as paver blocks, kerb stones, and so on. This apart, the HMWS&SB has planned to install screw turbines for hydel power generation at Amberpet and Nagole where STPs release treated water into River Musi at a steep gradient, officials said.