ExxonMobil Research Qatar and Providence Photonics, LLC, a U.S. based firm, are undertaking research to develop a Remote Gas Detection (RGD) system that integrates computer vision algorithms and infrared (IR) optical gas imaging technology to achieve autonomous remote detection of hydrocarbon plumes. The RGD system is designed to provide continuous surveillance and early warning to operations personnel in case of gas releases and to detect fugitive gas emissions.
The RGD system utilizes a custom built IR imager and integrated cooler assembly, and a computer vision algorithm that analyzes the video output from the IR imager to determine the presence of hydrocarbon plumes. Most hydrocarbons have strong absorption peaks in a narrow mid-wave IR (MWIR) region. The algorithm takes advantage of the difference in contrast between a hydrocarbon plume and the background in an IR image and the temporal changes due to plume behavior for the analysis. The algorithm compares sequentially collected IR images and uses a multi-stage confirmation process to confirm the detection. It has multiple filters that mitigate interferences like steam and other movement of objects in the scene such as humans, vehicles, and trees. Early field tests indicate that a 4 lb/hr propane leak could be autonomously detected from a distance of up to 800 feet.
The RGD camera assembly enclosure is designed to obtained explosion proof certification using the ATEX standard for deployment at classified/hazardous areas in oil and gas processing facilities. Instrument air provides cooling and is used to purge the system. Multiple deployment opportunities at process facilities are currently underway. Results from field testing at these process facilities will help researchers investigate the effect of temperate and harsh weather conditions, the effect of varying temperatures and gain a better understanding of equipment wear and tear, maintenance requirements and life expectancies. These data sets will produce an accurate assessment of the performance of the RGD system under actual working conditions and will be used to qualify the technology for widespread adoption within the industry.
Work has also been undertaken to compare the performance of the RGD system versus existing detection technologies. The most common leak detection technology is point sensors and path infrared sensors. This technology requires dispersed gas to physically contact the point sensors or move between two path detectors. Field tests are used to compare the performance of these mature technologies to the capabilities of RGD.