Airborne Gas Detection
Fugitive gas emissions have been estimated to create losses of up to 15% in some countries and create significant workplace hazards for ground staff entering an unknown leak zone.
MI Helicopters have successfully conducted aerial gas pipeline leak detection across many thousands of kilometres of pipelines in Queensland and are able to detect leaks accurately and more cost effectively when compared to ground based methods.
MI Helicopters can provide airborne gas detection surveys using the Boreal GasfinderAB system or the ALMA G2 (Airborne Laser Methane Assessment).
GasFinder AB & RedHen systems sDVR Geospatial video recorder with MediaMapper data presentation software
What is it?
The GasfinderAB is a laser based methane (CH4) detection system. The analyzer combines GPS location data to give highly accurate positioning for fugitive emission leaks. The live read-out display and alarm provide the operator with instantaneous gas concentration data.
Who manufactures it?
Manufactured by a Canadian based company – Boreal Laser. Boreal Laser Inc. and its predecessor, Aurora Laser Inc., have been developing laser systems since 1986 for the Canadian Forces Defense Research Establishments for licensing to private industry and for Boreal’s own manufacturing.
Since April 1993, Boreal Laser has concentrated on the development of laser-based gas detectors featuring the use of telecommunications diode lasers, fiber optics, photodetectors and related technology. Worldwide conversion of telephone and computer communications to this type of transmission has resulted in enormous demand for these telecommunications devices and correspondingly great development of reliability and reduction of cost.
How does the GasfinderAB work?
- The Gasfinder AB probe is attached beneath helicopter fuselage, the helicopter flies through the methane cloud to sense the gas leak.
- The Gasfinder AB central unit produces an infrared laser signal, which travels through a fibre-optic cable to the sensor probe.
- Methane gas deflects some of the laser beam reducing the amount of light received by the sensor.
- Higher methane levels results in more beam deflection.
- Laser frequency is methane specific – so no possibility of false detections from other particles.
- The difference between the emitted laser and received laser is measured to determine the gas concentration.
- GasfinderAB contains a pure methane vial for laser to self calibrate every few seconds.
- Constant read out to pilot of laser light levels, if laser levels low or machine calibration is not correct it automatically alerts pilot and ceases working – pilot cannot fly on and record inaccurate data.
- Able to detect CH4 from 0.5 ppm as gas passes through the sensor probe.
- GPS co-ordinates of leak automatically stored in computer.
How is the pipeline surveyed?
- The pilot is able to follow a real time moving map GPS route display of pipeline.
- Real time display of aircraft path, gas leaks and concentration (in ppm) presented to crew at all times.
- Audible alarm set for pilot at desired gas concentration to trigger closer investigation and high quality digital still image capture.
RMOTC Case Study
(Rocky Mountains Oilfield Testing Centre)
- Official Independent DOE (Dept of Energy) test in Sept 2006 conducted by Aviation Technology Services
- The study compared the Boreal GasFinderAB system to other technologies (including LIDAR, Passive Infrared Multi spectral Scanning, Hyper Spectral Imaging and Tunable diode Laser Absorption Spectroscopy)
- A simulated underground pipeline, 7.5 miles in length with 15 predetermined leak points
- Leak points/rates were blind to the testers and changed twice a day for the testing period.
RMOTC Test Results
The Gasfinder AB…
- Found 90% of all the gas emitted in the test
- Found 75% of all leaks.
- No previously tested system found more than 50% of leaks in the test.
- Leaks as small as 1.8scfh were identified.
- No other ground based or airborne system found leaks that minute.
“The performance of the system substantially exceeded prior evaluated detection systems at RMOTC. The test demonstrated the system’s strengths in measuring minute methane levels in the air”
Red Hen Geospatial Digital Video Recorder
- Red Hen sDVR records up to four channels of spatially geo-referenced video imagery.
- Complete geo-referenced digital video of entire pipeline recorded with high quality digital still images of points of interest and audio notes if required.
- Data is presented using Red Hen systems Media Mapper software.
- Complete track flown is displayed with simple colour coding for gas concentrations detected.
- Simply click a point on the track to play video of pipe section and display associated digital images and gas concentrations.
- Pipeline track can be overlaid onto satellite images, topo maps or company specific maps/charts.
Click on the images below to see some sample screen shots
- Methane concentration
- GPS location of leak automatically generated at alarm activation
- Full geospatially referenced video of entire pipeline and high quality geospatially referenced digital still images of detected leak sites.
- Aircraft position, speed and height
- Time & Date
- Additional comments from flight crew where deemed necessary
Airborne patrol advantages
- Above ground, below ground and underwater pipeline capable.
- Proven technology for over 20 years.
- Long range, fast, efficient patrols compared to ground based patrols.
- Wet weather capable.
- All year round patrols.
- Fast response for suspected leak situations.
- No ground disturbance to landholders or access problems.
- Extremely accurate leak identification – not subject to terrain limitations.
- No risk of ground crew entering high concentration methane areas during surveying/patrol.
- Aerial survey to ensure no significant leaks prior to ground crews conducting maintenance.
- The most accurate airborne gas detection system available worldwide – extremely high resolution.
- Fast, efficient, diverse airborne patrol system.
- Totally self sufficient operation.
- Extremely cost effective with significant economic savings over traditional ground patrols.
- Visual data presentation – no pages of figures or trolling hours of video – simply click the map to see the leak site and gas concentration.
ALMA G2 (Airborne Laser Methane Assessment)
What is it?
The ALMA G2 (Airborne Laser Methane Assessment Generation 2) is the solution for effective and economic pipeline and storage network monitoring and inspection. The ALMA G2 is the latest natural gas leak detection system, it is a cutting edge laser based natural gas detection system that performs inspections at ground level while airborne.
How does the ALMA G2 work?
The principle of ALMA is based on a pulsed beam from a diode laser, which is pointed at the location to be inspected. The laser wavelength of 1,65 μm corresponds to the first absorption band of methane. The laser beam aimed downwind of the pipeline, is reflected and the scattered reflection is collected by a receiving mirror, a photo-detector then receives the signal which is compared to the signal from a reference channel. (A laser beam through a curette with a standardized methane sample.) When methane is present the laser light will be absorbed, and the deformation of the signal is proportional to the concentration of methane along the laser beam path.
- Airborne device normally mounted on a helicopter
- Highly sensitive
- Real time measurement + alarm feature
- Wide measurement range
- Insensitive to other gases (water vapour, propane)
- Minimal interference with environment
- Pilot camera & monitor to aim laser
- Digital video recording to document laser position and area around pipeline
- Extensive data storage capacity
- GPS tracking
- Laser Range finder
- Extensive data storage capacity
- Post processing software
- Optional IR camera installation
- Optional moving map system for navigation