Portable System for the Measurements of Concentration, Isotopic Composition and Flux of Ambient CH4 and CO2 Released from Soil and Water

Recent work has shown that there are substantial methane and carbon dioxide emissions from microseepages of biogenic, thermogenic, and abiotic sources through the subsurface that are not included in the carbon balance. Research on microseeps with such low fluxes (10 100 mg m-2 d-1) requires highly accurate instrumentation that can measure ambient levels of greenhouse gases and their isotope ratio. These measurements can also aid in monitoring, evaluation, and development of gas shale deposits, where it would directly address recommendations made by the Secretary of Energy Advisory Board Subcommittee to provide greater transparency and reduce risks in the shale gas industry. In this SBIR program, Los Gatos Research proposes to work with GasConsult International Incorporated to develop a field-deployable system able to accurately measure the concentration, isotopes ratios (13C), and fluxes CH4 and CO2 emitted from the soil and water into the atmosphere. The system will utilize LGRs proprietary Off-Axis ICOS technology coupled with recently developed mid-infrared quantum cascade lasers to provide rapid (1 Hz) measurements of [CH4] to 1 ppb, 13C in CH4 to 1 , [CO2] to 0.5 ppm, and 13C in CO2 to 0.25 in ambient air samples ([CH4] ~ 1.8 ppm, [CO2] ~ 380 ppm). In Phase I, LGR will fabricate a mid-infrared Off-Axis ICOS analyzer for measurements of CH4 concentration and isotope analyzer at ambient levels. The analyzer will be tested on certified gas cylinders that span the expected observed range of soil emissions. LG will then work with GasConsult International Inc. to interface the Phase I Methane Isotope analyzer to a closed-chamber for gas flux derivation, and make field measurements in a variety of gas microseepage zones (natural gas seeps, sites with known leaks from underground systems). In Phase II, LGR and GasConsult will develop an autonomous, field-portable prototype that can provide rapid, spatially-resolved measurements of methane and carbon dioxide concentrations, isotope ratios, and fluxes. The sensor will include provisions for batch gas sampling, periodic calibration, and data reporting. Moreover, it will interface to both terrestrial and floating closed chambers to provide discrete measurements of soil and water outgassing. Finally, LGR and GasConsult will deploy the unit over a wide area with known gas exhalation, in order to show the rapidity and overall performances of the system. Commercial Applications: During Phase III, LGR will market its Off-Axis ICOS technology into a variety of markets including energy exploration and landfill management. A preliminary analysis suggests 5-year revenue of $1.8M $3M and $6M $12M for these market segments alone