Scanning, standoff laser-based leak imaging and quantification

Abstract

This paper reports a novel quantitative methane plume imaging tool, based on active near-infrared backscatter laser sensing technology. It integrates a laser sensor with a video camera in a future handheld package to create a highly sensitive imager that also quantifies emission rate. It provides colorized quantified images of path-integrated methane concentration independent of background. The images depict methane plumes overlaid on a visible camera image of the background. This new tool addresses the need for reliable, robust, low-cost sensors to detect, image, and quantify fugitive methane emissions, enabling operators to prioritize repairs. We built a prototype platform that demonstrated quantitative performance in the laboratory and municipal field tests. Based on measured signal-to-noise ratios, it can quantify emissions as small as 0.25 scfh in seconds.