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Projects: Projects for Investigator
Reference Number NE/E01657X/1
Title Crude oil oxidation without an electron acceptor; syntrophic hydrocarbon degrading microbes work together to "crack" a tough problem.
Status Completed
Energy Categories Fossil Fuels: Oil Gas and Coal(Oil and Gas, Other oil and gas) 25%;
Fossil Fuels: Oil Gas and Coal(Oil and Gas, Enhanced oil and gas production) 75%;
Research Types Basic and strategic applied research 100%
Science and Technology Fields ENVIRONMENTAL SCIENCES (Earth Systems and Environmental Sciences) 100%
UKERC Cross Cutting Characterisation Not Cross-cutting 100%
Principal Investigator Prof I (Ian ) Head
No email address given
Civil Engineering and Geosciences
Newcastle University
Award Type R&D
Funding Source NERC
Start Date 01 August 2007
End Date 31 July 2010
Duration 36 months
Total Grant Value £420,379
Industrial Sectors Transport
Region North East
Programme Standard
 
Investigators Principal Investigator Prof I (Ian ) Head , Civil Engineering and Geosciences, Newcastle University (99.998%)
  Other Investigator Dr N (Neil ) Gray , Civil Engineering and Geosciences, Newcastle University (0.001%)
Dr M (Martin ) Jones , Civil Engineering and Geosciences, Newcastle University (0.001%)
Web Site
Objectives There are six specific objectives of the proposed research. These are listed below and aimed at obtaining fundamental quantitative information on the properties of organisms responsible for methanogenic crude oil biodegradation such as growth yields and kinetics. These data can be used in future for modelling of anaerobic crude oil degradation both in contaminated anoxic sediments and groundwater, but also potentially in studies of biodegraded petroleum reservoirs. In addition, details of the biogeochemistry of anaerobic alkane degradation will be tackled by building on data from our preliminary studies that suggest novel carbon mineralization pathways may be involved in methanogenic crude oil degradation. Finally we will attempt for the first time to isolate a Marinobacter sp. which can degrade alkanes in the absence of oxygen. 1. Establish quantitative relationships betweencrude-oil alkane degradation and the abundance of putative syntrophic alkane-oxidizing bacteria Syntrophus sp. and Marinobacter sp. 2. Determine the growth rate and yield of putative anaerobic hydrocarbon degrading bacteria in mixed consortia 3. Establish if Syntrophus spp. and Marinobacter spp. are re p resentative of other methanogenic crude oil degrading systems. 4. Determine the terminal oxidation pathways in systems where methanogenic degradation of crude oil occurs. 5. Determine if similar pathways are involved in methanogenic alkane degradation and established anaerobic alkane degradation pathways. 6. Isolate a Marinobacter sp. from a methanogenic crude oil-degrading system that can gro w anaerobically on n-alkanes. These objectives will met within the framework of the following six hypotheses. 1. Syntrophus sp. and Marinobacter sp. are quantitatively important in syntrophic oxidation of crude-oil alkanes. 2. Long lag phases in methanogenic crude oil degradation are a consequence of low initial populations and low growth rate and yield of syntrophic hydrocarbon oxidizing bacteri a. 3. Syntrophus sp. and Marinobacter sp. are important members of many methanogenic crude oil-degrading systems. 4. The prevalence of hydrogenotrophic methanogens in methanogenic crude-oil degrading systems canbe explained by one of two mechanisms. I. Acetate generated from alkane oxidation is converted to hydrogen and CO2 by syntrophic acetate oxidizing bacteria II. Syntrophic alkane degrading ba cteria are capable of completely oxidizing alkanes to CO2 and hydrogen. 5. Methanogenic degradation of alkanes in crude oil involves novel alkane activation reactions. 6. Some Marinobacter sp. are capable of syntrophic anaerobic crude oil alkane oxidation.
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 petroleumreservoirs. 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 thebiosphere 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 biodegradedpetroleum 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 consortiumthat 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. Firstlywe 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 anoxicgroundwater 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 howquickly 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.
Publications (none)
Final Report (none)
Added to Database 05/06/08