Laser Analyzers for Quantitiative Measurement of Methane Emissions

If you're looking for professional advice on methane analysis by means of an open-path laser-absorption spectrometer or a mid-infrared tunable-diode laser spectroscope, follow the links for the relevant e-Learnings. Similarly, if you're in need of information on hyperspectral infra-red imaging for any-state methane, take a look at Jean-Phillipe Gagnon of Telops Inc.'s lecture on the topic. Finally, click through to find an overview of new sensor technologies for methane analysis.

"Open path laser gas monitoring is now well established as a preferred technique for the detection of leaks and fugitive emissions of toxic and greenhouse gases from industrial operations. The usefulness of the technique has recently been enhanced by combining data from multiple open path measurements with meteorological data and dispersion modeling, making it possible to estimate with good accuracy the magnitude and source of unplanned gas releases and their potential impact on downwind receptors. Measurement resolution and accuracy required for successful implementation of quantitative models places increased demands on the ability of commercially available open path laser gas analyzers to correct in real time for spectroscopic and chemical effects of variations in ambient pressure and temperature. Boreal Laser's new GasFinder3 laser analyzer platform has therefore been developed to meet measurement accuracy and resolution requirements of better than 1% and 0.2% respectively over an ambient temperature range from -40oC to +60oC. Design improvements implemented to achieve improved performance and application flexibility are described.

Two multiple channel configurations based on the GasFinder3 platform are now available. The first uses a single laser gas analyzer mounted on a programmable scanner enabling up to 8 successive open path measurements on path lengths up to 500m. In a fully configured 8-path installation, gas concentration data are updated once a minute. This configuration employs auto alignment and wireless data communications to enable continuous unmanned operation. The scanning configuration is ideally suited to long term environmental monitoring applications. Example installations and data presented include: CH4 (and CO2) emissions characterization from Oilsands mine sites in Canada; CH4 emissions from biogas energy production in Germany; CH4 (& NH3) emissions characterization in agricultural operations in Europe and North America.

The second configuration is a dual channel analyzer with 2 fixed measurement paths for use in leak detection applications where fast response (less than 5 seconds) and suitability for use in hazardous areas is required. Data from successful implementations of this configuration for CH4 leak detection from natural gas storage caverns and CH4 (& H2S) leak detection in sour natural gas production are presented.

The laser gas detection technology described has also been miniaturized to meet payload requirements of less than 1 kg for deployment on Unmanned Aerial Systems (UAS or UAV). Methane measurement surveys conducted with the UAV mounted laser gas detector are described. The new laser gas analyzer configurations presented enable improved safety and environmental performance with limited capital investment and very low operating costs."