Human waste disposal in innocuous form is an ever growing problem leading to aesthetic nuisance, threat of organic pollution & several infectious diseases in epidemic proportions due to contamination of ground water and drinking water resources in highly populated and developing countries, like India. Less than 30% of Indians have access to the toilets. In rural areas about 10% of houses have toilets and rest of the people go to open defecation. Population in the cities although have better access to the toilets but only to the tune of ~70%. Untreated waste is responsible for several diseases like, dysentery, diarrhoea, amoebiasis, viral hepatitis, cholera, typhoid etc. taking the life of lakhs of children annually.
Our own Defense Research Development Organisation (DRDO) has perfected an eco-friendly bio-degradation technology for human waste disposal for armed forces deployed at high altitude locations and glaciers. The sub-zero temperature does not allow the natural biodegradation of organic matter leading to accumulation of the human waste over the years, contaminating the ice which is the only source of drinking water and poses a great health risk. Further, melted ice contaminates the rivers and other water sources and ultimately spreading the contamination downstream. DRDO developed Bio-digester technology is environmental friendly, maintenance free and efficient without depending on conventional energy sources. The effluent is odorless and gets rid-off most of the pathogens.
Hundreds of such bio-digesters have been installed at various locations in J&K, Sikkim and Arunachal Pradesh. The bio-digester technology has two components: anaerobic microbial consortium and specially designed fermentation tank. The microbial consortium has been made by acclimatization, enrichment and bio augmentation with the cold active bacteria collected from Antarctica and low temperature areas. It is composed of four clusters of bacteria belonging to hydrolytic, acidogenic, acetogenic and methenogenic groups with high efficiency of biodegradation.Fermentation tank is made of metal/ FRP and has the provision of immobilizing the bacteria in large numbers.
Subsequently, the technology has been extended to Indian Railways for on-board treatment of human waste. Hundreds of stainless steel made bio-digesters are in operation in different trains of IR. Under a Memorandum of Understanding (MoU) with Railways, it is planned to install these bio-digesters in all trains in the years to come. Lakshadweep administration had ordered 12000 bio-digesters for all houses of its ten islands. Low cost single house bio-digesters have been designed for rural sector of the country which is long-lasting, require little space, generate environment-friendly safe effluent and does not require any maintenance. Recently developed version of this technology has been named as ‘BioTank’ that is the excellent low cost alternative of the conventional septic tanks being currently used by individual houses and communities.