The ABB Ability mobile gas leak detection system is a frequently used tool in a wide range of gas network applications, particularly in terms of leak detection.
Image credit: ABB.com
ABB’s patented gas leak detection system is currently available in car-based and handheld versions. These instruments are primarily based on robust ethane/methane gas analyzer hardware, with methane detection being the main goal of the hardware discussed in this article.
ABB’s service offering includes a wide range of gas leak detection systems, with the company’s portfolio currently extending into stationary systems and UAVs over the past two years.
This article begins by exploring ABB’s motivation and approach to business, as well as a brief overview of the company’s history. It then looks at some of the technical details of gas mobile leak detection systems before moving on to focus on the company’s leading UAV systems.
ABB’s Motivation and the Importance of Gas Network Maintenance
ABB is motivated to develop, enhance and provide modern gas leak detection services because of examples of the worst-case scenario.
One prominent example of this worst-case scenario was a gas pipeline explosion that occurred in 2010 in San Bruno, close to Los Angeles and Los Gatos, the origin of ICOS gas detection technology by the company Los Gatos Research (LGR).
These kinds of harmful disasters prompted LGR to develop technologies designed to measure methane and ethane, for example, in ambient air with a high level of sensitivity and accuracy. This was a turning point in the development of overall gas leak detection technology.
The central idea behind this technological advancement was improving the avoidance of explosion risks. These risks may occur due to aging infrastructure, particularly from the use of cast iron steel.
Most gas network pipelines were installed at the start of the 20th century, making many of these installations over a hundred years old and in need of replacement.
Safety concerns – particularly around loss of life and property – have prompted the need for preventative and ongoing maintenance of this aging gas network infrastructure. PR has also been a concern for many providers as once a company starts to have problems with its network, the public will quickly become aware of this.
There is also the potential for fines, regulatory penalties or even criminal prosecution in cases where negligence is proven to be a cause of a gas explosion or other accident.
Environmental consciousness is also a major driver of the need for improvements to gas network infrastructure. While this has always been a central concern, it is now at the center of public attention, adding increasing pressure to governments and industries.
Reducing greenhouse gas emissions is essential, particularly because CH4 is one of the most prominent greenhouse gases besides CO2, and the issue of ethane/methane evaporating out of installed gas sources remains ongoing.
All of these methods and technologies must have efficiency and survey speed considerations at their core due to the sheer amount of gas network pipelines to be managed. In the US alone, there are approximately 2.2 million miles of natural gas pipeline and around 1,000,000 wellheads.
Each country and often region will also have different regulations, so as well as efficiency leading to cost savings, gas detection equipment must be adaptable enough to be able to accommodate different local requirements.
ABB’s Gas Leak Detection Systems: A Brief Timeline
The car-based MobileGuard system was first introduced in 2016 in Los Gatos, California. The MicroGuard handheld solution was launched at the same time.
In 2018, ABB started to introduce this technology into the European market, centering this around a campaign in central Europe by working with Achema, based in Frankfurt, to demonstrate both the MobileGuard system and the MicroGuard system to a wide range of interested stakeholders.
In 2019 these systems were also introduced into the Asian market.
The Avant Garde UAV-based measuring system began to be developed and tested in 2020. This leak detection system is designed to be fitted close to installations and observed by local operators.
The market release for this system has been delayed due to the current COVID-19 pandemic, and is now expected to take place sometime in 2022.
Traditional Approaches to Gas Leak Detection
Generally speaking, each country or region maintains its own regulatory requirements, and these will impact the gas leak detection technology being used.
The actual survey technology differs, but in many instances, this will involve a trained operative with a handheld unit walking above the pipeline or the network grid at various sites within the city limits, trying to detect leaks in a very localized way.
The technology is sensitive, offering detection limits from 100 ppm up to several percent of volume. This approach will only work effectively when the pipeline is close to the ground, however.
These same principles are also applied to car-based systems. A laser measuring system will be fitted in the front of the car, using a relatively wide beam area to determine whether or not there is a potential methane leak.
Car-based systems are still required to drive slowly above the pipeline or the network grid to ensure acceptable levels of sensitivity; for example, 10 to 100 ppm at the lower end of the range, up to a small volume percentage of methane in the air.
Most of these systems rely heavily on the training and diligence of the people conducting the survey from that point of view. The systems are often paper-based, meaning that the surveyors are required to write reports which are then passed to the owners of the network grid.
If a third-party organization is offering this service on an outsourced basis, this will also need to be added to the documentation.
The founding principles underpinning automated logging of gas leaks via GPS were first published in 1995, so this approach has a long history. This paper made use of GPS and anemometer data along with a form of gas chromatography technology.
This system had to be housed in a truck because of its size before running tests to identify released trace molecules of CH4 and SF6. The tests involved a series of canister samples used to take a sample during the test runs.
These tests evaluated the distance between the release station and the point at which the car passed by, as well as how effectively the concentration could be measured and any effect that wind has on the technology.
By taking into account all of these factors, it was possible to extrapolate the original source of the CH4 or SF6. ABB has taken this innovative technology and optimized it.
Optimizing Gas Leak Detection with MobileGuard
ABB’s optimization approach involves considering a range of typical survey conditions and localized regulations. For example, it is not possible to complete the survey when the ground is frozen – the temperature should be above freezing, and the soil should be dry, ideally at least three days since the last rainfall.
Survey interval frequency will also depend on the number of leaks found in the past, with verified past leaks requiring increased numbers of surveys of the network pipeline and vice versa. The pipeline’s age and construction will also impact requirements around the frequency of surveys performed.
The survey will be performed by the grid owner’s employees or by external contractors, with regional regulations and guidance often outlining specific levels of experience and qualifications for personnel.
The ultimate goal of all the approaches outlined here is finding leaks as quickly as possible, but many traditional methods are unreliable and slow because of the reduced sensitivity of the units. ABB's solution is able to detect leaks extremely quickly, however.
MobileGuard from ABB is a car-based hardware solution that is comprised of the LGR ICOS ethane/methane analyzer and a GPS antenna that detects the speed and positioning of the vehicle.
A sonic anemometer detects the wind direction and velocity, while the inlet of the gas analyzer in front of the car collects the sample for measurement. This information is collated and passed to a software package that analyzes the data, visualizes it, and provides the surveyor with feedback on the location of potential leaks, therefore prompting them to investigate these more closely.
MobileGuard performs leak analysis in real-time, offering direct feedback to the user. There is no need to send the data to a remote computer or cloud-based application because all the data is analyzed and visualized within the vehicle itself.
Remote real-time monitoring of vehicles is also possible, however. After each survey trip, data can be collated and sent to a cloud application via LTE, allowing colleagues, analysts and stakeholders to access historic data as required. Cloud storage also offers the advantage of digital reporting, and compatibility with GIS systems, for example.
Demo cars are currently in operation in Cologne, and options are available for Volkswagen, Nissan and Ford cars and vans; the only requirement being a roof rack for the anemometer and sufficient trunk space for the battery. The instrumentation is compact enough to be used in even a small car.
The rack version of the MobileGuard includes a GPS system connected to a central unit, which is in the trunk. The gas inlet is in the front of the car, and a 12-volt direct current power supply is integrated into the vehicle.
Off-Axis Integrated Cavity Optical Output Spectroscopy (ICOS)
The MobileGuard employs the patented Off-Axis Integrated Cavity Optical Output Spectroscopy (ICOS) system. Gas enters a cavity cell and a laser is introduced from one side to a mirror, then reflected several times as it interacts with the gas sample. Pressure and temperature are controlled, and the spectrum is measured and evaluated.
Sensitivity is ensured by the sheer number of reflections taking place within the cell. The MobileGuard system makes use of around 10 kilometers of path lengths with a dynamic range capable of handling large amounts of data and measuring from 1 ppb to 10,000 ppm without any changes to the optical setup.
The light beam needs to be precisely directed to the detector’s collecting lens, but vibrations from driving or even flying do not affect the reflection area’s ability to collect data. The key advantage of ICOS over a conventional tunable diode laser system lies in its sensitivity which goes down to ppv-levels.
ICOS is able to measure ethane down to around 5 ppb, meaning that it can observe small leaks from large distances.
Response times are around 5 Hz, meaning five measurements can be taken per second, directly deriving the concentration of the gas even if the vehicle is moving at speeds between 30 kilometers per hour (in a city, for example) and 70 kilometers per hour (on a motorway, for example).
This also means that vehicles performing gas leak detection do not hinder traffic or require any special markings or sirens to warn other drivers.
ICOS ensures that there is no interference from ambient compounds or higher hydrocarbons because it is specifically examining the absorption bands of the spectra representing methane and ethane. This also allows the method to remain calibration-free and the analyzer incredibly easy to service.
The analyzer can be serviced in the field; for example, if the initial 70-micrometer filter in the front of the inlet nozzle becomes blocked. In this instance, the filter can be removed, cleaned and then replaced, allowing the analyzer will return to running normally.
MobileGuard’s system can successfully conduct measurements in a wide temperature range, from -50 °C to 50 °C. Most gas detection regulations do not allow measurements when it is -5 °C outside, for example. The vehicle’s internal temperature is also important.
The vehicle’s driver should feel comfortable, and if it is hot outside, they may wish to switch on the cooling system in the car. This would also cool the analyzer which must be kept within its ideal operating temperatures.
User Interface and Mapping Capabilities
A powerful user interface displays the surrounding area using GPS map data, showing the current gas detection calculations, the route driven and the area evaluated. The map style can be changed between satellite view or a more data-driven system with color-coded concentrations displayed along the route that has been driven.
This color-coding highlights the concentration of methane in terms of its ppm, showing if gas was detected above the set threshold and also if gas was detected within the set threshold.
The software interface allows the driver to monitor a range of factors as they perform the survey, for example, gas concentration levels and ambient temperature, along with wind direction and speed.
Measurements can be started at the touch of a button, and a number of options are available that allow users to change the system’s data management options.
The status of the analyzer is available at all times, and visual or auditory feedback is available as to whether or not the current gas measurement is within the user-defined acceptable threshold.
Feedback is also available on gas flow, pressure and temperature, allowing the user to monitor the system’s operation and ensure this is working properly. Colored lights confirm whether each component is working correctly, requires attention or is malfunctioning.
The software also offers user management features, allowing different users to be set up with different access levels.
If a potential leak is detected, the software’s modeling capabilities allow it to provide a robust evaluation of where the leak may have originated from, along with information on the potential margin of error for the calculation.
This information is provided in real-time, allowing users to respond to a leak or potential leak immediately, minimizing the risks outlined earlier.
Routes can be optimized by using assets within the software package. Assets include GIS information on the network grid being investigated. Information on old pipelines can be digitized and uploaded into software and to directly see where assets, pipelines, and the network grid is located.
That means areas where users would need to drive to can be matched with GPS map data and asset inventories, allowing users to ascertain quickly and easily which, if any, of their assets are causing a suspected leak.
This data is currently being used with the Google Drive cloud storage system, which is security certified to ISO 27001.
ABB plans to migrate this to the Microsoft Azure Cloud Solution in the future, however, allowing raw data to be better evaluated by analysts and colleagues. The driver completing the survey is responsible for deciding when and what data is uploaded to the cloud.
The data is outputted as comma-separated tables (CSV files) or XML data, meaning it can be easily imported into applications like Excel or software that reads the data via machine learning.
Data can then be evaluated separately using a different software package or directly imported into a database alongside GIS compatible, KML, KMZ, or SHP data. It is possible to use this data to view suspected leak sites directly via Google Earth, or these layers can also be imported into an in-house GIS system.
Finally, reports can be automatically outputted as user-friendly PDF documents, ensuring readability for stakeholders, managers or other colleagues who are less able to interpret raw or technical data.
All of MobileGuard’s software has been subjected to rigorous cybersecurity hardening and testing for the software package. ABB has employed stringent measures to secure the software according to recognized cybersecurity regulations and cybersecurity rules, allowing the system to be used securely in the field and with cloud-based systems.
Handheld Gas Leak Detection with MicroGuard
MicroGuard is ABB’s second mobile gas leak detection system. The MicroGuard system is essentially a micro analyzer consisting of a sample wand connected to a tablet or phablet (an extended tablet with mobile phone capabilities).
MicroGuard offers a very high level of sensitivity for methane coupled with fast measurement and low weight of around 5.8 kilograms. The system can run for four hours between charges. One key feature of the MicroGuard system is that it can share data with the MobileGuard car-based system.
If a survey has been done with the car, it is possible to upload the data into the cloud, download the data via the phablet and use this to better pinpoint the location of the suspected leak on foot.
The MicroGuard’s software interface offers a number of features in line with that of the MobileGuard software, including the use of GPS data to track where the user has walked and the provision of color-coded information on gas concentration.
Using the phablet, it is possible to take a photo of the area containing the leak, and this can be attached to the report or sent to the cloud for colleagues or maintenance teams to access.
The Future: Drone-Based Mobile Gas Detection with HoverGuard
HoverGuard is a new application in development that applies the same gas detection principles as the MobileGuard and MicroGuard but on a remote controlled drone.
Again, this system makes use of an analyzer (referred to as Air Frames), a GPS system, a sonic anemometer, and a drone where this is installed. The setup is very similar to the car-based system, with the same interface and software package.
A very strong 900 Mhz modem is used to connect to the analyzer rather than the drone, which can be supplied by the user in line with recommendations and advice from ABB.
Reports and the information from the software package also include XML data, or comma separated values (CSV), as well as KMZ and KML data which can be viewed with Google Earth.
After each flight, a PDF report is generated, which can be uploaded directly from the laptop to a cloud-based system, so long as this is connected to an LTE network or Wi-Fi router.
Data is generated rapidly because the analyzer will be flying at speed, and like the car-based system, the HoverGuard is able to operate in temperatures between -50 °C and 50 °C. The system uses the patented ICOS system and has a payload of around three kilograms.
Summary
ABB offers a portfolio of gas leak detection systems, all based on the same software package. These systems are suitable for use in a vehicle, UAV, drone or in a stationary instrument.
Data is portable and this can be sent to cloud storage as required, allowing easy access from colleagues, peers, analysts or stakeholders. All of these solutions will also directly create reports after the survey is finished.
ABB provides a portfolio rather than just one solution. For example, if a customer starts with a vehicle-based system, this can be enhanced with a UAV, portable or stationary system as required by the users.
ABB’s portfolio has delivered ongoing and proven performance since 2015, and the company’s products are sold and distributed globally to different areas of the world with different regulations.
ABB’s portfolio offers comprehensive solutions ideal for use in different areas, and the company’s full range of instruments is robust, reliable and very sensitive thanks to their fully featured hardware and software. Cybersecurity is central to all of ABB’s software packages, and the customer owns and controls all of the data. Because detection thresholds can be set by the user, it is easy to meet appropriate regulatory requirements regardless of where in the world the instruments are being used.
Servicing the instruments is simple and straightforward, and users can do this themselves, or they can ask ABB for support. The company’s service offering is not available in every country, but in the US, for example, ABB can even go as far as performing the survey for the customer, removing the need for training and maintenance.
Using ABB’s portfolio of gas leak detection solutions affords customers a competitive advantage via more efficient surveying.
Customers are able to do more surveys in less time, with one recent demo determining that in one week, a customer using ABB’s portfolio of instruments could perform as many surveys as they could in two to three weeks using their old method.
This ensures enormous gains in terms of time while allowing gas network operators to react faster and more efficiently to existing leaks or leaks that have the potential to develop.
MicroGuard, MobileGuard and HoverGuard instruments can be integrated with customers’ existing data with ease. The instruments offer a short warm up time of around two to three minutes.
Overall, ABB’s complete portfolio of instruments is a competitively priced option for anyone wanting to find leaks faster, better ensuring the safety of the public, staff, assets and company reputations.
This information has been sourced, reviewed and adapted from materials provided by ABB Measurement & Analytics - Analytical Measurement Products.
For more information on this source, please visit ABB Measurement & Analytics - Analytical Measurement Products.