| abstract |
Apparatus and methods for rapid detection, location, imaging, and quantification of natural gas and other hydrocarbon and greenhouse gas leaks. Scanning sensors, scanning modes, and data processing algorithms enable monitoring of sites for rapid detection, localization, imaging, and quantification of the amount and rate of hydrocarbon leakage. Multispectral shortwave infrared detectors sense nonthermal infrared radiation from natural sunlight or artificial lighting sources through differential absorption spectroscopy. A multispectral sensor is scanned to encapsulate an area of interest, the presence and location of a leak is detected, and the area surrounding the leak is raster scanned to create an image of the leak. The resulting absorption images for the differential spectral optical depth are color-mapped to present the extent of gas absorption across the scene. Analysis of this optical depth image using factors including known line pressure and/or surface wind velocity measurements enables an estimate of the leak rate, ie, an estimate of the emission mass flux of the gas. |