From trash to cash: Unlocking the hidden potential of animal waste

Seetha Gopalakrishnan
Friday, December 19, 2014 - 11:58

It is a well known fact that India is a treasure trove of livestock. The total output from livestock products exceeds that of grain production. But, milk, meat and skin are not the only precious resources available. 

With over 512.05 million cows, buffaloes, donkeys, mules, sheep and pigs in the country, it is interesting to note that precious animal waste is usually not paid as much attention.
Wealth from waste
Traditionally, Indian farmers have incorporated waste recycling in their everyday lives. Cattle dung is used as manure and so is the urine. More recently bio-gas plants have come up in many parts of the country, but it would not be inaccurate to state that animal waste generated on a daily basis is not used to its maximum potential.
The Total Sanitation Campaign (TSC) identified the potential that lays hidden in animal waste and set aside 10% of its total allocation to deal with solid and liquid waste.
Lucknow’s Bio-energy Cell collaborated with the UNICEF to develop a biogas system powered by solid waste, thereby addressing the twin dilemma of managing solid waste generated as well as providing a cost effective energy source. 
These bio-digesters were capable of processing kitchen as well as farm waste. The design provided for ten such digesters to work simultaneously, each with the capacity to deal with 200 kilograms of waste per week. The process is completely anaerobic and after four or five days, the digestion process gets underway. 
Energy cum fertilizer powerhouses
The gas that is released as a by product of this anaerobic digestion is composed of methane, carbon-di-oxide (CO2 ) and hydrogen sulphide (H2S). Since methane is the only usuable energy source, CO2 and H2S are removed by passing the gas through lime water and iron fillings respectively.
While the resultant methane gas is used for cooking and heating purposes, the nitrogen and phosphorus rich residue that is left behind - the ‘biogas slurry’ - is used as a ferlilizer.
For the community, from the community
Three villages in Ballia and Lucknow districts of Uttar Pradesh housed these bio digesters on a pilot basis in 2008 and 2009. The community was involved right from the planning stage to monitoring of progress. Around 15-40 families contributed for each of these plants and a total of 90 families were able to benefit from the bio gas generated in each of the villages. 
Biogas users’ committees were set up which were later registered as societies. These societies took care of the operation and maintenance of the biogas plants which were up and running with material as well as monetary input from the community.
The simplicity of the model has inspired others replicate it. Similar plants were constructed in other districts of UP using TSC funds. States such as Tripura, Tamil Nadu, Gujarat and Andhra Pradesh were also interested in replicating the successes of Ballia and Lucknow.
Scope for improvement
One of the biggest constraints for implementing the scheme is the high capital investment of Rs. 8-10 lakh out of which 20% was community contributed. Mobilizing such a huge amount from the community is a formidable task. Another which greatly influences the sustainability of the programme is operation and maintenance. Unless the community takes ownership and views these plants as assets, their future is rather bleak. 
If obstacles are identified and addressed with tailor made solutions at the onset, these bio-digesters have the capacity to be a blessing for most power starved villages in the country.