Unearthing the role of microbiology in shale gas extraction: a bioreactor approach

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More than 1300 trillion cubic feet of natural gas is estimated to reside in UK shale formations, kilometers below the surface. This resource has the potential to fuel the nation for decades, and bridge the energy gap between the UK's dependence on coal and oil towards the sustainable renewable energies of the future. Natural gas is locked away in tight spaces within shale. To recover this gas for use as a fuel, these deep shale formations must be artifically fractured by a process called hydraulical fracturing. This process involves pumping millions of litres of water and chemicals into a horizontally-drilled well at high pressure, causing fractures to open through which natural gas can flow unimpeded. Although the government supports the exploitation of the UK's natural gas reserves, there is deep public concern over the environmental risks of hydraulic fracturing, triggered by widely publicised reports of environmental damge from hydraulic fracturing in the US. Whilst a comprehensive independent report deemed the risks of extraction to be low when conducted properly, these concerns must be addressed in order for the full potential of UK economy to benefit from this resource to be met.A number of chemicals that are added to injection water during hydrualic fracturing are known to stimulate microorganisms, and in particular microbial processes that negatively impact on natural gas and its extraction. These processes may lead, for example, to a depletion in additives in the input fluid (each of which serves a particular purpose in making shale gas extraction more efficient), as well as spoiling the natural gas, and causing corrosion of the well infrastructure. Collectively, these 'biofouling' processes lead to increased costs, reduced efficiency and a greater potential environmental impact.The research I propose is designed to tackle these issues. In partnership with a UK oil and gas servicing company, Rawwater Engineering Company Limited, I will test an array of injection fluid chemicals (individually and mixed together) for their potential to stimulate biofouling processes. These experiments will be conducted using bespoke, high pressure bioreactors that are designed to mimic the conditions of UK shale formations. Throughout these experiments I will apply state-of-the-art techniques to monitor changes to the chemistry and microbiology, and in doing so unearth the role of microbiology in the efficiency of shale gas extraction.The results of this research will shed light on the potential for injection fluid chemistry to stimulate biofouling, as well as the types of microorganisms that are responsible for these processes. In partnership with Rawwater and their links to the wider oil and gas industry, these results will allow me to develop diagnostic tools and control strategies that can be applied to field operations in order to maximise the efficiency and hence minise the environmental impact of shale gas extraction, to the benefit of the UK economy.