EDMONTON – Bacteria that feed on coal seams and create methane gas could be coaxed to produce more of the clean-burning fuel, a new source of energy locked in the world’s vast coal deposits.
That’s one of the goals of a major project begun this summer at the University of Alberta, part of a three-year national study which aims to shed some light on the little understood microscopic world of anaerobic bacteria that live in coal and produce the gas which is recovered though coal bed methane extraction. Methane is the same gas that causes deadly explosions in coal mines.
“We are studying the methanogenesis process, part of the metabolic cycle of the microorganisms,” said Sushanta Mitra, associate professor of mechanical engineering and director of the micro- and nano-scale transport laboratory at the National Institute for Nanotechnology.
That involves identifying the different microorganisms in various coal seams; understanding what chemicals can be added to natural communities of bacteria to encourage them to produce more methane; what factors limit the rate of natural production; and how fluid moves through coal.
Developing sensors and monitoring tools, and then moving to field testing with major natural gas producer EnCana Corp. will follow.
“Our goal is to have full-sized field testing underway on an underground coal seam in Alberta by 2015,” Mitra said, adding his team is currently working with core samples from various coal deposits.
Alberta has some of the world’s largest deposits of coal, and technology developed here could be sold to other nations, as well as form the basis for a new energy industry.
Only five per cent of Alberta’s coal-bed methane resource can be extracted using current technology.
But the research holds the promise of extracting methane from very deep coal deposits.
And while the microbes slowly consume the coal, that does not mean cavities are created, adds Mitra. As part of the project, his lab is studying high resolution microscopy to examine the pore structure of coal and the microbial-coal interface.
In one area of Mitra’s lab, a “reservoir on a chip” — a geologically exact replica of a slice of a formation that has been duplicated mathematically — is used to study the flow of fluid through coal.
Mitra says studying the coal and lifeforms at the microscopic level will yield answers to the scientific questions that must be understood before techniques — such as what exactly to add to the microbes to how fluid will flow through the formation — will be successful.
While scientists around the world are studying methanogenesis, “we are the only lab that is doing this with nanotechnology. We expect to publish some interesting research from our work.”
With a variety of researchers in several fields, including biology, Mitra says wide collaboration is the future of research in nanotechnology.
“Collaboration is the nexus of this field.”
The coal-conversion project is supported by a $1.9 million grant from Carbon Management Canada, a research network funded by provincial and federal governments and industry.
Steve Larter of the University of Calgary is scientific director of the CMC and an investigator on the coal bioconversion project. He said recently that an interdisciplinary approach is critical the project’s success.
“The problem can’t be solved by a really good geochemist, or just a really good microbiologist, or just a very good engineer,” he said.
“We are trying to build an orchestra.”