Anaerobic treatment of low-strength wastewater (India)

CPCB 2021 Data shows that only 28% of urban India’s wastewater is being treated and remaining get discharged directly to the environment with partial or no treatment which will further pollute the fresh water sources. Therefore, the selection of technologies become very much important to suit the local conditions and with low operation and maintenance requirement become crucial. Anaerobic treatment technology comes with advantages of no aeration requirement, less sludge production, and efficient resource recovery has received much attention as an alternative process. This study focuses on understanding the applicability of anaerobic treatment for low strength wastewater, such as domestic sewage and greywater. Based on the literature review and access to the implemented sites and data, UASB, anaerobic baffled reactor and anaerobic filters are studied under this study. From case studies, its concluded that the anaerobic treatment modules like anaerobic baffled reactors and anaerobic filters are capable of achieving organic load (BOD and COD) reduction from 75-90%. The removal of nutrients (N and P) is limited, majorly aims at organic removal. Hence, advanced treatment technology needs to be added in series with the anaerobic process to achieve complete N and P removal.