Development of a low cost, lightweight imaging FTIR to detect and differentiate between biogenically and thermogenically derived hydrocarbon gas.

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The detection and quantification of methane gas emissions is a critical component of a wide range of environmental science processes and applications. Acquisition of sampling datasets with the essential spatial and temporal resolution and detection sensitivity to address the requirements of the key science questions, climate models and commercial users is a significant environmental challenge and poses a critical market need. A diverse range of researchers, interest groups, commercial and regulatory organisations require the detection, quantification and differentiation of hydrocarbon gases (methane, propane, butane, & ethane) at spatial scales ranging from point source to landscape scale.Identification of the sources and fluxes of methane into the atmosphere is a critical component of climate change research. A significant challenge to accurately quantifying the methane contribution is the spatial and temporal variability in methane emissions of many of the environmental processes, e.g. melting of boreal peatland, combined with the exceptionally large size of the affected areas. Fugative methane emissions are also of critical interest to a wide range of commercial and regulatory organisations. Gas emissions from landfill sites are a common environmental issue faced by councils and the environment agency while fugitive emissions from pipelines are a very expensive and inconvenient problem for many commercial organisations ranging from domestic supply to large-scale petro-chemical facilities.Detection of on-shore microseeps is a key objective of exploration hydrocarbon geoscientists as they are highly indicative of the presence of a hydrocarbon-rich basin. Microseeps are characterised by the emission of thermogenically derived hydrocarbon gas which usually contains significant concentrations of ethane, propane, butanes and condensate. Thermogenic gas geochemistry differs from biogenic gas, which consists almost entirely of methane, providing a direct, remote methodology for microseep identification. This detection capability could also be utilised to quantify the environmental impact of the exploitation of unconventional gas deposits (shale gas & coalbed methane). The volume, composition and duration of fugitive thermogenic hydrocarbon gas emissions from well sites is poorly understood. Continuous, complete, accurate measurements of hydrocarbon emissions over the entire well site could inform discussion of the environmental impact and influence decisions on future developments. All these applications require the acquisition of accurate, continuous measurements of hydrocarbon gas emissions over prolonged periods (night and day) over scales ranging from site to landscape. Current field-based methods for detecting hydrocarbon gas emissions cannot meet the requirements of researchers and users as they are time-consuming, costly and produce very sparse spatial datasets Remote-sensing based methods offer a potential solution however current techniques are either inaccurate (e.g. reflectance spectroscopy) or very costly and impractical (e.g. LiDAR).Currently available imaging based gas monitoring instruments are not capable of resolving the hydrocarbon gases with sufficient accuracy. Imaging Fourier Transform Interferometers (FTIRs) have the potential to detect and quantify hydrocarbon emissions but the current design of imaging FTIRs make them prohibitively expensive and cumbersome for operational deployment by environmental scientists.There is an urgent need for the development of a low-cost, highly portable, highly sensitive imaging system. The aim of this project is to undertake a laboratory-based study to develop, and validate a low cost, lightweight, compact imaging Fourier Transform InfraRed (FTIR) spectrometer with sufficient spectral resolution and radiometric sensitivity to detect, quantify and differentiate between biogenically and thermogenically derived hydrocarbon gas.