Discover Advanced Mobile Leak Detector (AMLD)
Physical Sciences Inc. (PSI) of Andover, MA and partner Heath Consultants Inc. of Houston, TX, recently presented a suite of new products for detecting, locating, and measuring natural gas emissions to the atmosphere. The urgency of complying with federal and state regulations to reduce methane emissions is driving earnest industry adoption of methane measurement and monitoring technologies. These new products are based on the laser technology underlying the Heath/PSI industry-transforming Remote Methane Leak Detector or RMLD®.
Methane, a potent greenhouse gas, is the dominant component of natural gas. Natural gas infrastructure leakage poses explosion and environmental safety hazards, and costs customers the price of lost gas. Methane accounts for about 10 percent of all U.S. greenhouse gas emissions from human activities. Maintaining the security and integrity of the natural gas system is a continual process of searching for, locating, and repairing leaks.
At the recent American Gas Association’s Operations Conference in Orlando, Heath introduced the new ultra-sensitive vehicle-mounted DISCOVER Advanced Mobile Leak Detector. It “discovers” small natural gas leaks in municipal distribution pipeline infrastructure. Using fast open-path RMLD® technology, Discover AMLD measures both methane and ethane during survey from a mobile platform. Ethane is a secondary component of natural gas – measuring it concurrent with methane discriminates natural gas emission from other methane sources such as sewer and swamp gas. DISCOVER AMLD approximates emission rate (an essential measurement for assessing the environmental impact of leakage) and the location of the leak.
At the CH4 Connections Conference in Ft. Collins CO, PSI and Heath presented the RMLD-QGI (Quantitative Gas Imager). Currently in development, QGI supplements the RMLD® optical engine with a programmable fast laser scanner and visible camera within the handheld RMLD® platform and package. RMLD-QGI captures quantitative video images of methane plumes emanating from gas leaks and deduces emission rate from these images.
The industry-transforming Heath/PSI RMLD® is an eye-safe handheld battery-powered laser-based methane sensor. It works much like a flashlight – shine the infrared laser beam onto a surface and RMLD® reports how much methane gas is between the operator and the surface. An audible alarm sounds when it detects a high concentration or quickly changing gas cloud indicating a plume emanating from a pipeline leak. Unlike handheld gas “sniffers” that are common tools for detecting gas leaks, RMLD® need not physically probe into the gas-filled area, only the laser beam passes through the plume. RMLD® detects leaks smaller than 0.5 scfh.
Since its introduction in 2005, the RMLD® has become a standard tool for natural gas leak surveying of distribution pipelines. In 2020, Heath released a modernized RMLD-CS®, a smaller and lighter version of the original with advanced performance features. Nearly 7000 RMLD® units have been deployed worldwide, spawning numerous competitive products. The handheld RMLD® detects methane plumes as the surveyor manually scans the laser beam across the plume path. QGI enhances RMLD-CS® with plume visualization and emission rate quantification. In projects sponsored by O&G industry operators and R&D organizations, PSI’s QGI prototypes captured unique video images of small fugitive leaks from municipal distribution pipelines, and quantified the leak rates in real time. In a current NIOSH-funded SBIR project, the QGI optical engine has been packaged into a first-prototype handheld unit.
The RMLD® platform also underlies the fixed-position Remote Emissions Monitor (REM) that continually monitors for gas plumes within or on the perimeters of gas storage or processing sites. Building upon PSI’s 30 year legacy developing and deploying open-path laser technology, PSI with Heath pioneered continuous long-open-path monitoring of methane emissions from O&G storage tank batteries and underground storage sites more than six years ago. REM projects the laser beam along a line-of-sight from the optical unit to a passive target that may be more than 1000 ft distant. It continuously monitors, rapidly detects, and reports unintentional (“fugitive”) methane emission alarms at natural gas gathering, storage, pipeline, and other operational infrastructure sites. REM’s sensitivity, data rate, and simplicity provide unique statistical data to patented algorithms that identify emission plume signatures, often smaller in magnitude than slower natural variations of methane. REM has been deployed at more than 30 sites since 2015; its data was some of the first to reveal previously undetected large intermittent fugitive emissions. EPA recently announced that PSI will be awarded funding to accelerate the scale-up and deployment of REM products.
The compact RMLD-CS® optical engine, mounted on a small quadrotor unmanned aerial vehicle (a drone), forms the RMLD-UAV™, developed in part with funding from the Department of Energy’s Advanced Research Projects Agency (ARPAe). The laser beam projects from the drone downwards to the surface and measures methane along the laser path. Upon operator command, the laser-equipped drones can autono¬mously launch and survey wellheads, compressors, storage sites (both above and underground), and pipelines from an altitude of 10m, create quantified maps of emissions depicting the emission source overlaid upon a visual image of the area, process the mapped information to deduce the rate of emission (flux) independent of ambient background, and report results to operators in near real-time.
For further information, see our recent 4C Conference presentation or contact:
Physical Sciences Inc.
Industrial & Environmental Sensors Group
20 New England Business Center
Andover, MA 01810
Heath Consultants Inc.
9030 Monroe Road
Houston, TX 77061