The “Nisargruna” biomethanation plant set up by Mangalore City Corporation using the technology developed by Bhabha Atomic Research Centre (BARC), Mumbai, near Urwa Market here has begun functioning.
Environment Engineer at the corporation Madhu S. Manohar told The Hindu that the corporation had planned to use the energy (methane gas) produced at the plant to operate a generator. The generator in turn would supply power to Urwa Market and operating machines at the plant. He said the plan was to achieve self-sufficiency in power supply in operating the plant and supplying power to the market.
Mr. Manohar said the plant had been set up for reducing the quantity of bio-waste being transported to the corporation's compost plant at Pachchanady and instead use the waste to generate energy. With this, the corporation would achieve the twin objective of saving the cost of transporting the biowaste to the compost plant and reduce volume of waste being lifted from the market.
The biomethanation plant which started functioning in the last week of November 2011 had the capacity to process up to two tonnes of biowaste a day. The two tonnes of bio waste could produce between 100-160 cubic metres of methane gas. It could produce up to 200 units of power, Mr. Manohar said.
“The plant produced 261 cubic metres of methane gas from November last week to first week of January,” Mr. Manohar said.
He said its operation had to be stopped later as its main digestion doom developed a snag. It was rectified and it started functioning a few days ago.
The plant had been set up by Wipro Eco Energy under the guidance and technology provided by Sharad Kale, Professor, Homi Bhabha National Institute, and Head, Pesticide Residues and Soil Science section Nuclear Agriculture and Biotechnology Division, BARC.
Mr. Manohar said the kitchen waste from some hotels, vegetable and green waste from Mannagudda, Boluru, and Derebail South-West wards were shifted to the plant for producing the gas.
The engineer said it took three months for the plant to reach its full capacity as bio-waste had to be fed in the quantity prescribed in phases. For example, there would be no feeding of waste for the first fortnight after beginning the operation. In the next fortnight, 500 kg of waste could be fed. Between 31 days and 45 days, the quantity could be scaled up to 750 kg. Later, it could be increased to 1,000 kg, 1,500 kg, and up to two tonness for the 90th day in phases.
He said now the two motors, a compressor, and a mixer at the plant were being operated by using power supplied by Mangalore Electricity Supply Company Ltd.
Mr. Manohar said the corporation council had approved the purchase of a generator.
Professor Kale told The Hindu that “Biogas generated in any biomethanation plant is a mixture of methane and carbon dioxide. The biogas generated in Nisargruna process contains more percentage of methane than the conventional process. Since the percentage of methane is higher, the flame would be better, and calorific value higher in case of biogas generated in the plant.”
