Biogas-linked Toilets

Biogas-linked Toilets

Context: Despite cultural, technical and other challenges, Kolhapur makes progress in adoption of biogas-linked toilets

More on the News:

• 25% of the toilets in Maharashtra’s Kolhapur district are linked to biogas units that convert the waste to fuel while tackling faecal sludge on the spot.
• This is significant given that in general in India, there is a taboo attached to using human excreta to generate biogas, which is then used in cooking.

Biogas:

• Biogas is based upon the use of dung to produce gas which is used as domestic fuel, especially in rural areas
• Biomass has always been an important energy source for the country considering the benefits it offers. It is renewable, widely available, carbon-neutral and has the potential to provide significant employment in the rural areas
• The technique is based on the decomposition of organic matter in the absence of air, to yield gas consisting of methane(55%) and Carbon Dioxide(45%), which can be used as source of energy.
• Procedure to make Biogas
• A typical biogas plant in India has cow dung as its main feedstock and consists of three parts – an inlet from where dung mixed with water is fed, a digester, and an outlet connected to a slurry collection tank. The human toilet is directly connected to the digester via a PVC pipeline and does not require manual handling.
• The increased pressure from the gas forces out the slurry, the by-product of the process, into the slurry storage tank. The slurry, retained in the digester for 20-30 days, decomposes most pathogens and weed seeds, making nitrogen-rich manure.
• Biogas is derived from waste, unlike bioethanol or bio-diesel, so it does not involve competition with land and biodiversity for food products.
• It can be used as cooking and lighting fuel; and the left over slurry serves as an enriched manure
• This has taken deep roots in India, as it has higher thermal efficiency when compared with Kerosene, firewood, dung and charcoal
• About 32% of the total primary energy use in the country is still derived from biomass and more than 70% of the country’s population depends upon it for its energy needs.

Schemes:

• Biomass power & cogeneration programme: is implemented with the main objective of promoting technologies for optimum use of country’s biomass resources for grid power generation. Biomass materials used for power generation include bagasse, rice husk, straw, cotton stalk, coconut shells, soya husk, de-oiled cakes, coffee waste, jute wastes, groundnut shells, saw dust etc.
• Ministry of Drinking Water & Sanitation has launched the GOBAR (Galvanizing Organic Bio-Agro Resources) – DHAN scheme to convert organic waste, especially cattle waste, to biogas and organic manure for use in rural areas.