Microbes (green & orange spots) stained with a fluorescent dye, growing on crushed coal samples.

Microbes growing in coal seams can enhance methane production.

Using microbes to enhance gas production

For the first time in Australia, CSIRO scientists have cultured indigenous microbes which are active in coal seam gas reservoirs and produce secondary biogenic methane.

  • 24 February 2010 | Updated 14 October 2011

Coal seam gas is becoming a widely used energy source, particularly in eastern Australia where a number of basins have been found to produce significant volumes of methane gas from coal seams.

Coal seam gas is cleaner than other fossil fuels and already accounts for over 40 per cent of Queensland’s natural gas consumption.

Many of the high-methane production zones are confined to regions of microbial gas generation.

Research shows that microbial activity enhances the gas saturation levels of the coal, with areas in the Sydney Basin of Eastern Australia showing considerably higher production rates of coal seam gas in coal which contains secondary biogenic gas compared to areas containing only thermogenic gas.

What CSIRO did

The CSIRO project brings together the capabilities of CSIRO’s Earth Science and Resource Engineering and Food and Nutritional Sciences divisions to investigate where methane gas production can be enhanced by augmenting and stimulating natural microbial activity.

Researchers are conducting laboratory experiments to understand the processes involved and are culturing the microbes to determine the viability of using them to optimise gas generation.

The process of biogenic gas formation requires the collective actions of a variety of anaerobic microbes comprising a range of metabolic groups, and other conditions such as:

CSIRO scientists have cultured indigenous microbes which increase methane gas content of coal seam gas reservoirs.
  • temperature
  • availability of nutrients
  • appropriate substrates.

These considerations are a key component of the research.

A long term field trial will eventually be undertaken where microbes and nutrients will be injected into the reservoir.

Outcomes

If successful, the benefit for industry of this research includes the development of a technology to increase methane content of coal seam gas reservoirs which could: 

  • add considerable value to coal seam gas production
  • increase production of this energy source in Australia.

Production of methane gas from coal seams by this method should also create additional capacity in those structures for the geological storage of carbon dioxide (CO2).

Ultimately the technology may enable the conversion of some of the CO2 stored in coal seams to methane gas, delivering further environmental and economical benefits.

Partners

A number of industry partners have already been engaged to support the project.

Read about Using microbes to improve oil recovery.