Pilot 6 – Anaerobic digestion with electrically conductive biofilter

Location: Kharagpur (West Bengal)
Pilot Leaders: CENTA/IITKGP
Pilot Status: Pilot Status: Pilot is ready, operation will start after receiving EC media from CENTA

Water challenge in this location: IIT Kharagpur campus and nearby states are facing water challenges where people are mostly relying on groundwater source for meeting the water demand. Also, the sanitary infrastructure in this part of country is extremely poor and most of the people are relying on septic tank for treatment of black water and effluent of the septic tank is released in the environment, leading to pollution of surface and groundwater. Hence affordable solutions need to be demonstrated for sustainable decentralized black water treatment for minimizing the water pollution and protection of public health.

Benefits of the technology: The electroconductive biofilter provides the following benefits: Simple operation, robust design, low space requirements, less energy consumption (apart from pumping if required) and zero production of sludge. The electroconductive biofilter will be followed by sand filtration (providing SS and turbidity removal) and disinfection by means of UV –lamps and electrodisinfection (low energy requirements; on site generation, no handling and storage of chemicals; low generation of trihalomethanes). Solar panels will be employed for energy supply in the disinfection unit; thus, increasing the long-term sustainability of the proposed treatment plant.

Potential for India: This system can either be used as secondary or tertiary treatment as an add-on to existing treatment plants, or in combination with e.g. an UASB reactor as in this pilot for complete treatment of blackwater. As outlined earlier, there is a high need of simple and robust wastewater treatment system and therefore this system has a high potential for application in India.

Scope of replication/upscaling across India: As the technology will be locally constructed and implemented as a post treatment of an existing UASB reactor (which also was locally built as part of the Saraswati project) there is a great potential for replication and up-scaling of both the combined package of UASB reactor and post treatment as proposed in this pilot, and the post treatment as an add-on to existing blackwater treatment plants.

Main outcomes: Reuse of the final effluent obtained for irrigation, gardening, flushing, etc.