Cow dung by day, methane by night
Without posing a threat to the ecosystem, a pilot project of bio-gas plant in Karachi's Bhains colony converts tonnes of manure into gas and electricity. Is the government listening?
By Rabia Ali
Muhammad Ibrahim, 65, a resident of Lath Village, located in Bhains Colony, hangs his head in despair as he surveys the scene outside his house, situated next to the sea.
Every day, tons of cow dung mixed with chemicals and pesticides make their way into the sea, polluting both the water and all that surrounds it. Ibrahim, who is a fisherman by profession, says he cannot recall when he last fished in these waters as the marine life has been dead for a while now. "I am now worried about my children and livestock who are surrounded by this *****."
Interestingly enough, the answer to Ibrahim's problems lies a few kilometers away in the Shaukat Mukhtar Farm, Bhains Colony No 12. Here, a bio-gas plant functions silently, and converts four tonnes of manure to methane gas every day. This, in turn, produces 600 units of electricity and 200 cubic meters of gas.
The pilot project, which is the first of its kind in the country, may well change the living conditions in Bhains Colony, one of the largest cattle colonies in the region, housing over 400,000 cattle heads.
According to the project consultant, Naseem Aziz, "The plant was installed in the farm some six months ago by a British Company, HiRAD PLC. The gas produced by the plant is used to heat up around four houses of the farmers, dwelling in the locality. The same bio-gas is also used to produce electricity through a generator."
HiRAD says its system is quick, converting the manure produced in a day into power. It is typically installed to the farm's existing storage facilities with minimal disruption. It does not require an energy crop or external waste streams and its outputs all have a value.
The gas is used to produce electricity, the solid waste is composted and used as a soil treatment, and the liquid is a premium fertiliser, claims the company.
Giving details about the operation of the plant, Aziz explained that "the pump of the plant first mixes the cow dung with water. After the mixture is prepared, the solid waste is separated, and is later on used in the production of fertilisers. The dung and water mixture is then forwarded to a main reactor, where bacteria (aerobic digester) present in the dung produces methane when it is heated at 37`C. This very methane is then used to produce gas and electricity."
Shakeel Nasir, the man in charge of the operations, concurs. "The amount of methane produced by this method is 70.1 per cent whereas carbon dioxide 30 per cent." Nasir said that his is the only company in the country that produces methane in such large quantities. The farm utilizes the waste of 300-350 animals, efficiently and effectively, without posing a threat to the eco-system.
The company hopes to replicate this system with the 1,200 cattle pens and farms that are located in this colony.
These farms simply dump around 8,000 tons of cow dung into open drains every day. Since no proper system prevails in the colony for disposal, the dung eventually reaches the Arabian Sea.
The potential of using this manure can be gauged from the dung lagoon located downstream of the farms where bacteria present in the dung produces methane under the open skies. No reactor is needed to provide heat to the bacteria, as the sun's heat is enough.
The question now is whether or not the project will be able to take off. Residents of the area, however, cannot wait for this to happen. "Due to the presence of the cow dung, our people have lost their livelihoods. Boats have rotted, fish in the nearby seas have died, the foul odour has infiltrated our environment and the area has been infested with flies and other insects," says Iqbal, a resident of Lath Village.
Though Iqbal and his community people have appealed to the government several times, there has been complete silence from the other end. With 2009 being declared as the Year of the Environment, several people's hopes are pinned on those with power – that they may be able to turn the tide for those living in Lath Village.
Kolachi, NOS, The News International