Performance and comparative assessment of DRDO bio-digesters

The research aimed to understand and evaluate whether the standardisation of DRDO biodigesters as a product across DRDO biodigester technology licensees has achieved consistency in effluent quality irrespective of the differences in licensee products in terms of factors such as materials, immobilisation matrices and designs. The research also aimed to analyse the performance of these products against the locally available onsite sludge treatment options. The DRDO biodigesters and the local alternate onsite sanitation technologies in India and Nepal were part of the study. The effluent and influent quality analysis was done for the parameters informed by the literature review. The comparison between the effluent quality was supplemented with the qualitative data collected from users and the DRDO biodigester licensees. The study has established a theory on the standardization achieved amongst DRDO biodigester products for attaining consistency in effluent quality. It was found that environment in which the biodigester work influences its effluent quality even though the standardization has been achieved. The DRDO biodigesters have shown better performance over the local alternate sanitation technologies in use especially in terms of BOD reduction and user satisfaction. The study has contributed to bridging the knowledge gap on the standardisation of the DRDO biodigester products and identified potential factors affecting biodigester effluent quality consistency.