Bacteria have been discovered that break down oil into methane

An international research team has proven the existence of bacteria capable of breaking down oil into methane, carbon dioxide and hydrogen. The discovery may bring about a revolution in oil production in the world and promote more 'green' energy

An international research team has proven the existence of bacteria capable of breaking down oil in reservoirs around the world. Their discovery, published in the prestigious scientific journal Nature, could bring about a revolution in oil production in the world, by finding a more efficient and environmentally friendly way to create the 'black gold'.
The breakdown of crude oil into heavy oils while in oil reservoirs has been an international problem for the oil industry. The decomposition process is caused by bacteria that feed on the oil, make it viscous and compressed and contaminate it with by-products such as sulfur. Refining such reservoirs and extracting oil from them is a difficult and expensive task.
Several studies have hypothesized that biodegradation of oil can occur by aerobic bacteria, which need oxygen to live. In the new study, the group claims that the main process that leads to the breakdown of oil is a process of fermentation, caused by anaerobic bacteria that live in oil reservoirs and do not need oxygen to live.
"This process happens in every oil reservoir on the planet," says Larter, a geoscience researcher at the University of Calgary. His research colleagues come from Newcastle University in England and Norsk Hydro Oil & Energy in Norway.
With the help of microbial studies, laboratory experiments and studies in the oil fields, the group showed that hydrocarbons undergo decomposition without the presence of oxygen, and methane is obtained. The findings raise the possibility of 'feeding' the bacteria with oil, and simultaneously accelerating its decomposition into methane.
"Instead of the process taking 10 million years, we want to do it in 10 years," says Larter. "We think it is possible. We can do it in the lab. The question is: Can we do it in an oil reservoir?"
If the researchers are successful in their mission, they will turn the oil and tar sands industry upside down. Tar sands are a mixture of sand, clay and bitumen. The bitumen can be separated from the tar sands and in a simple but expensive process distill it into synthetic fuel or fuel products. The largest tar sands deposits known to man are in Canada, and it is estimated that 180 billion barrels of oil can be produced from these deposits, making them the second largest oil reserves in the world. Now that the beneficial bacteria have been discovered, the hope is that the tar sands industry will not have to use expensive and polluting processes to release the heavy hydrocarbons from the tar sands. Tar sands mining companies will be able to choose to use up only the natural gas - methane - and leave the bitumen and pollutants at the bottom of the reservoirs.
If the method is indeed implemented on a large scale, its important advantage will be in the creation of 'green energy'. "We will get much cleaner fuel," says Larter. "If you compare methane and bitumen, for each unit of energy, much less carbon dioxide is released into the air. Besides, we won't need all the refineries and pipelines on the surface anymore."
The research group also discovered an intermediate step in the natural decomposition process. It turns out that the process involves a separate group of microbes that produce carbon dioxide and hydrogen from semi-decomposed oil, before the anaerobic bacteria turn it into methane. The research opens the door for using microbes to capture the CO2 as methane, and recycle the methane as fuel in a closed system. This process will ensure that CO2 - a greenhouse gas blamed for global warming and climate change - does not reach the atmosphere.
Understanding the natural breakdown process can also be used to predict where in the reservoirs the oil is located that has not yet broken down too much. This understanding will allow the oil companies to increase oil extraction by targeting higher quality oil.
The oil industry has already expressed interest in trying to accelerate biodegradation in an oil reservoir, Larter says. "Field tests will most likely begin in 2009."
The research group was headed by representatives of England from the University of Newcastle - Ian Ide and Martin Jones. The multi-talented group included experts in petroleum geology, microbiologists, organic geochemists and reservoir draftsmen. The group's findings were published on the website of Nature.

For information on the University of Calgary website