Crude oil oxidation without an electron acceptor; syntrophic hydrocarbon degrading microbes work together to 'crack' a tough problem.

Lead Research Organisation: Newcastle University
Department Name: Civil Engineering and Geosciences

Abstract

If you were asked which countries have the most oil, you would undoubtedly answer with the name of one of the large oil-producing countries in the Middle East such as Saudi Arabia or Kuwait. Although these countries do have vast oil reserves (Saudi Arabia's Ghawar oil field alone, is estimated to contain in excess of 260 billion barrels) they are not actually the largest oil deposits on Earth. This honour is held by the gigantic petroleum deposits in Western Canada (Athabasca tar sands) and Venezuela (Orinoco heavy oil belt) which each contain well over 1 trillion barrels of oil. The giant oil fields in the Americas are less well known than those in the Middle East because, over geological time, the oil which they contain has been biodegraded by microorganisms living in the petroleum reservoirs. Biodegradation removes the most valuable components leaving behind heavy viscous tar-like oil which is much more difficult and expensive to produce and refine than the free-flowing oils from the Middle East. Increasing oil prices and finite hydrocarbon resources mean that heavy oil fields represent an economic resource of growing value, but they also provide a unique window on the biosphere found deep within the Earth's crust. Geochemical measurements have shown that petroleum biodegradation in oil reservoirs is probably caused by anaerobic hydrocarbon-degrading bacteria and geochemical modelling suggests that they operate at rates thousands of times slower than they do in near surface environments. If we are to better understand the processes that lead to the formation of giant biodegraded oil deposits, more active experimental laboratory-scale anaerobic oil biodegradation systems are required. A major end product of anaerobic oil degradation in many biodegraded petroleum reservoirs appears to be methane gas, however there are only very few examples of methanogenic oil biodegradation in the literature. We have recently obtained a methanogenic microbial consortium that converts oil to methane at rates which are measurable in the laboratory (these are however still very slow processes). The objective of this research is to understand what organisms are quantitatively significant in the conversion of crude oil to methane and what factors dictate their activity in the environment. When we have this information the benefits will be several fold. Firstly we can begin to assess the geochemical controls on crude oil biodegradation in petroleum reservoirs on geological timescales. This has potential benefits for petroleum exploration where geological formations that may have had conditions conducive to petroleum biodegradation may be avoided. It will also prove valuable for understanding what controls the fate of spilled petroleum released to anoxic groundwater or sediments. There is even the possibility that residual oil in petroleum reservoirs, which cannot be recovered by conventional means, could be converted to more readily recoverable methane gas. This research will tell us what organisms are capable of methanogenic oil biodegradation, how they interact with each other and what controls their activity. In addition we will learn how quickly they can convert oil to methane and other end products, information that can ultimately be used to predict the behaviour of crude oil in a range of environments.
 
Description The project has shown that the capacity for methanogenic crude oil biodegradation is widespread, though limited in pristine environments. It has identified the key organisms and processes responsible for syntrophic alkane oxidation and indicated that novel mechanisms of alkane oxidation may be involved. It has also shown that volatile hydrocarbons can retard the rate of hydrocarbon degradation under methanogenic conditions, though the final extent of degradation is not markedly affected. This has implications for understanding the processes that lead to the formation of the world's heavy oil deposits, points towards means to recover energy from stranded oil in petroleum reservoirs as methane and has implications for the fate of crude oil in anoxic sediments which are common in many coastal areas including coastline impacted by the 2010 deepwater horizon blow out.
Exploitation Route Our research has implications for understanding the processes that lead to the formation of the world's heavy oil deposits, points towards means to recover energy from stranded oil in petroleum reservoirs as methane.



It also has implications for the fate of crude oil in anoxic sediments which are common in many coastal areas and estuaries and also in anoxic contaminated aquifers. As a consequence of presenting the results of our research at relevant symposia we have been approached by small consulting companies involved in mitigating detrimental effects of anaerobes in petroleum systems, novel molecular detection tools for hydrocarbon degraders with potential application in prospecting and larger oil companies wishing to explore the potential of metagenomic approaches to better understand and manage the biological component of their resources.

We have also successfully applied for a Marie Curie Incoming International Fellowship to develop the fundamental microbiology of syntrophic hydrocarbon and we are now part of a 34-partner EU-KBBE project on oil in marine environments (Kill*Spill) that involves a number of international companies and SMEs. We have also been successful in developing a collaboration with an international energy company which is funding a project on the microbial ecology of petroleum systems.
Sectors Energy,Environment
 
Description Outputs from research conducted as part of this project and related industry funded projects include use by oil companies for determining optimum well placement in heavy, biodegraded oil reservoirs and have been used by the Alberta Energy Regulator for informing development guidelines. The work is also cited as a source in a science fiction novel (Petroplague). This formed the basis of a highly ranked Impact Case Study in Newcastle University's UoA7 REF2014 submission.
First Year Of Impact 2008
Sector Energy,Environment
Impact Types Cultural,Economic,Policy & public services
 
Description EU FP7 Knowledge Based Bioeconomy
Amount € 350,000 (EUR)
Organisation European Commission (EC) 
Sector Public
Country European Union (EU)
Start 01/2013 
End 12/2016
 
Description Collaboration on reservoir souring with Rawwater Engineering 
Organisation Rawwater Engineering Company Ltd.
Country United Kingdom of Great Britain & Northern Ireland (UK) 
Sector Private 
PI Contribution Analysis of microbial communities in high pressure system exhibiting souring
Collaborator Contribution Operation of high pressure reactors, provision of samples, staff time
Impact Platform presentation: 21st Reservoir Microbiology Forum. November 2015. London. Pressurised, sand-packed bioreactors to demonstrate the impact of downhole pressure on the sulphate-reducing microbial community
Start Year 2015
 
Description Microbial ecology of petroleum reservoirs with Shell 
Organisation Shell Global Solutions UK
Country Netherlands, Kingdom of the 
Sector Private 
PI Contribution Postdoctoral Researcher seconded to sponsors labs in Houston, conducting metagenomic analysis and microbial community analysis on a range of petroleum-releated samples
Collaborator Contribution Funding, Provision of samples, bioinformatics support
Impact Vigneron A, Alsop EB, Chambers B, Lomans BP, Head IM, Tsesmetzis N. (2016). Complementary microorganisms in highly corrosive biofilms from an offshore oil production facility. Appl. Environ. Microbiol. doi:10.1128/AEM.03842. Platform presentation:5th International Symposium on Applied Microbiology and Molecular Biology in Oil Systems. June 2015. Stavanger Microbial profiling insights from an offshore oil field in South East Asia Platform presentation: 21st Reservoir Microbiology Forum. November 2015. London Linking subsurface geochemistry to microbes and MIC through metagenomics and multivariate analyses
Start Year 2014
 
Description Joint Oil Company-OILSPORE workshop 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Professional Practitioners
Results and Impact Project only recently inititiated, however we held a workshop on 26-27 March with representatives from an international oil company as part of our pathways to impact plans

Representative from our research group and oil company personnel presented areas of research of potential mutual interest. This was conducted in an open forum to allow participation of research students and research associates and was followed by a small
Year(s) Of Engagement Activity 2013
 
Description Visit to Rawwater Engineering 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Industry/Business
Results and Impact Meeting with potential industrial partner to discuss potential research collaboration.
Year(s) Of Engagement Activity 2015