Australian researchers and engineers will trial a breakthrough that promises to dramatically increase gas yields from coal seams and biogas plants, thanks to a partnership with India's largest oil and gas producer.
The deal between India's Energy and Resources Industry, the Oil and Natural Gas Corporation (ONGC) and the researchers at the University of New South Wales will be the first trial of the technique in an industrial application. The project is being supported by a $1 million grant from the Australian India Strategic Research Fund.
The researchers found that crystals formed from neutral red dye increased gas yields from microbes living on organic waste by up to 18 times. This breakthrough could extend the life of coal seam gas wells, and greatly boost gas yields from bio-digesters that consume carbon-neutral organic waste and generate methane for electricity production.
The researchers have already replicated these gains in gas volumes both inside and outside of the laboratory, with successful tests in coal seams west of Sydney.
The Indian trials, which will see the technique applied to coal seam gas wells operated by the Oil and Natural Gas Corporation, will allow the researchers to further refine aspects of the technology, ensuring that it is ready for industrial use, and taking into account critical variables such as coal seam pressure and temperature, as well as enabling the development of new technologies to precisely introduce the dye.
“This is very exciting and likely to be a game changer,” said the project’s leader, UNSW Associate Professor Mike Manefield. “There is a lot riding on natural gas, or methane, to help bring global emissions down as the world transitions to cleaner fuels,” he said.
“As gases burn far more efficiently than solids, you emit half as much carbon dioxide for the same amount of electricity when you burn gas, compared to coal.”
The discovery was partly happenstance, when the research team were using the common dye, phenazine neutral red, while investigating methane-producing microbes. These "methanogenic archaea" live in coal seams and on organic waste, producing one billion tonnes of biogas a year.
At the right concentration, the dye forms crystals that act as electron sponges that "power up" the microbes, boosting their growth and methane production. With accelerated microbial growth, the amount of methane emitted also increases.
This accelerated methane production will not only allow industry players to extract much more energy from each coal seam gas well, but the process may also open up new sources of gas. In India, many of the country's untapped coal deposits consist of younger, softer coal, which are not viable to mine commercially. However, soft coal is much easier for methane-producing microbes to digest, so the synthetic dye process could transform these deposits into coal seam gas developments.