Leaks from natural gas transmission pipelines can present a significant safety hazard, as well as being harmful to the environment and extremely costly to producers.
Now drones are to be put to work to sniff out gas leaks from transmission pipelines, thanks to a mobile detection system developed by ABB.
The system, which is capable of sniffing out even small leaks from a distance of up to 100m away, uses the company’s industrial Internet of Things (IoT) platform, ABB Ability, to allow it to upload signals to the cloud for immediate analysis anywhere in the world.
The system is based on technology originally developed to allow scientists to detect trace gases in the atmosphere.
To make the technology suitable for use in the oil and gas industry, the company reduced the size and weight of the system, allowing it to be flown by drone, said Doug Baer, global product line manager for laser analysers at ABB.
“There aren’t always roads where there are transmission pipelines, so in order to access and detect possible leaks in hard-to-reach areas like on bridges or underwater, you need to fly,” said Baer.
Unlike conventional systems, which need to be close to a leak to detect it, the device can sniff even a few molecules of methane above the atmospheric baseline level of 1800 parts per billion, from great distances away, he said.
The self-contained box is equipped with a vacuum pump that pulls ambient air inside, and two mirrors. A laser beam is shone through the measurement cell, where it bounces back and forth between the two mirrors many times before exiting the device and being detected by a photodetector.
As a result, although the measurement cell is only 10cm in diameter, the laser beam travels several kilometres, said Baer.
“That means you need far fewer molecules (of gas) in the pathway to detect a signal, than you would if the pathway was only 10cm,” he said.
The system is capable of measuring methane and ethane, the two largest components in natural gas.
By using ABB Ability, signals detected by the system can be immediately uploaded to the cloud for storage and analysis by a remote operator using a secure connection, Baer said.
The system’s software automatically processes the collected methane and ethane data, as well as GPS and wind information, to produce a report, which can be used to quickly identify areas in the pipeline that have leaks.