Biodigester Technology for Effective and Ecofriendly Decomposition of Nightsoil

Abstract

Adequate sanitation and hygiene practices are essential for maintaining the good health. In developing countries, rapid increase in population and urbanization has put tremendous pressure on the existing infrastructure related to the sanitation, thereby necessitating development of more effective technologies. Among the sanitation practices, proper disposal of human excreta assumes much significance as it is one of major sources of human pathogens. Various technological solutions are available for treatment of human fecal matter. Employing the principles of anaerobic biodegradation, biodigester technology has been developed by Defence R&D Organisation, India, for effective decomposition of human fecal matter under varied geoclimatic conditions. The present article deals with the biodigester technology, its uses, and possible impacts on overall sanitation scenario in India. Chemistry and biology of anaerobic degradation of nightsoil using a unique anaerobic microbial inoculum and a bioreactor are also discussed. In addition, we highlight the factors governing the biodegradation efficiency, effluent quality as well as possible recycling/reuse of water and harvesting, and use of methane generated from it. Also, based on the critical and in-depth analysis of existing scientific information, we further deliberate on future prospects of this technology for sustainable and ecofriendly treatment of nightsoil in developing countries.