Technology Targets Fugitive Emissions

Figure 1. One person now can do work that had required two to monitor fugitive emissions. Source: RFS Compliance Solutions/Bronson Pate.

The day is long gone when monitoring required two field technicians. Today, one person can carry a handheld device and directly upload recordings to the leak detection and repair (LDAR) electronic database (Figure 1), notes Bronson Pate, global vice president, RFS Compliance Solutions, Bozeman, Mont., who has extensive experience developing and implementing LDAR programs, both in the U.S. and elsewhere.

“The software, which operates on my ECOM, also is able to run diagnostic checks on my phx42 [flame ionization detector (FID)] and submit a support ticket immediately from the field if I run into any issues,” Pate adds.

Meanwhile, the requirement to monitor fence-line emissions has brought much more interaction with plant neighbors over issues such as smells from a facility and potential contamination of local water supplies or soil.

“RFS Compliance Solutions has the ability to put technology on the fence line which does instantaneous monitoring down to the part per billion (ppb) level and can connect directly to the control room, notifying when an emission is detected at the level set by the facility,” he says.

Drones are another technology on the move — especially in the use of the latest infrared (IR) video and camera technologies.

“Over the past few years, drones have become more popular for large projects as they allow facilities to have instantaneous video of what is happening at any given moment. In the U.S., they are used for everything from checking pipelines to monitoring emissions in cases of emergency response,” Pate explains.

“Regulations and communities are driving these changes. As new regulations are enforced, industry is turning to the newest technologies and bringing in subject matter experts to train staff on the new requirements and, in some cases. helping them to design new process units. However, there does need to be constant and respectful communication between the end user, contractor and facility departments for any LDAR/fugitive emission reduction program to succeed,” he cautions.

Benefits To Personnel

Fugitive gas monitoring provides an important tool to enhance the safety of workers and increase their productivity, emphasizes Chris Munnelly, director of product marketing, Honeywell Industrial Safety, Scottsdale, Ariz.

“Worker safety is significantly improved when compliance to safety regulations are met, which includes regular bump testing and calibration as well as timely exposure reporting. Additionally, there is a need to understand the condition of the worker in real time: was there a significant gas exposure and/or man-down incident? And where is the worker located so he/she can be rescued? A safe worker is a more productive worker — one with more time to dedicate to tasks, and fewer incidents to impede efficiency,” he notes.

“Continuous innovation is crucial,” adds Diederik Mols, business leader industrial wireless, Honeywell Process Solutions, Amsterdam, pointing to advances in personal gas safety sensors as examples.

Honeywell’s latest offering, the MicroRAE, is a wireless, multi-gas diffusion monitor that simultaneously measures up to four gases including hydrogen sulfide, carbon monoxide, oxygen and a range of combustibles’ lowest explosive limits (LELs). It relays in real time instrument readings, location and alarm status to plant safety systems.

Many sites employ a mix of both fixed and portable gas detection. However, Mols points out that portable gas detectors alone frequently handle some applications such as monitoring an area not often entered by personnel, where fixed gas detection is cost-prohibitive or where placement of fixed gas detectors is impractical. In addition, some duties require the detector itself not being stationary. Changing legislation and regulatory mandates, combined with evolving insurance requirements, also are spurring greater use of portable gas detectors.

“Remember, too, that such devices are ‘sniffing’ constantly while in use, providing a wealth of information to the plant software. In terms of safety, they inform the control room within 30 seconds of any user being overcome or injured, either during an incident or on routine inspections,” he stresses.

“All fugitive gas monitors can improve operating performance as gas releases may hint at other operating issues that need to be addressed,” adds Munnelly.

Picking the right location for fixed gas detectors usually requires the advice of experts with knowledge of gas dispersion, combined with the insights of process/equipment engineers and safety personnel, the two caution.

However, as a rule, detectors should be mounted where the presence of gas is most likely, for example, around gas boilers, compressors, pressurized storage tanks, cylinders or pipelines. Monitoring of other equipment susceptible to leaks such as valves, gauges, flanges, T-joints as well as filling and draining connections also often makes sense. Gas density, pressure and temperature should be considered, too, along with ease of access for functional testing and servicing.

The Honeywell specialists second Pate’s point that regulatory compliance is driving the issue of perimeter monitoring.

“You want to be able to assure a local population that the plant is safe. This is especially important in Europe where large chemical complexes are often close to towns and cities. Traditionally, a lot of these sites are wired and it is expensive and time consuming to install all the extra cable needed for high-density fugitive gas measurements. Wireless is much quicker and more cost effective,” says Mols.

The use of wireless technology will continue to rise because many more chemical companies now have greater faith in its robustness, he predicts.

“Innovation will make this happen even more quickly. While Honeywell would never advocate ripping all the wires out of a control system, it is the case that a well-designed and well-implemented wireless network is as robust — if not more so — than a wired network,” he concludes.

Corporate Initiatives

Another example of how the technology is developing comes from BP, London. In September, the company announced that it will deploy continuous measurement instruments such as gas cloud imaging to all new major projects worldwide (Figure 2). This is part of an effort to better detect, measure and reduce methane emissions that ultimately aims to achieve BP’s methane intensity target of 0.2% from its upstream operations.

Figure 2. Continuous measurement instruments play a key role in corporate initiative to reduce emissions. Source: BP.

The technology has been tested and installed in current facilities such as BP’s natural gas Khazzan field in Oman and is a key part of a wider and longer-term strategy to deploy a suite of complementary methane-detecting methods across new and existing facilities. In time, the data collected will feed information into an extensive digital cloud network as part of a global integrated approach to reduce both methane and carbon emissions.

Besides continuous methane measurement, BP also aims to more broadly use within all its operations complementary technologies, including a new generation of drones equipped with lasers and methane “sniffing” capability, hand-held devices and multi-spectral flare combustion cameras.

One drone successfully tested by the company circled its Clair offshore platform near Scotland’s Shetland Islands for 90 minutes. The fixed-wing remote-piloted air system (RPAS) operated at a radius of 550 metres for 90 minutes and travelled over 185 km (Figure 3). The pre-programmed drone, once airborne, managed itself autonomously.

Throughout the flight, the RPAS live-streamed valuable data collected by a SeekIR miniature methane sensor supplied by SeekOps, Austin, Texas. Next year, that company expects to add hand-held and vehicle-mounted sensors.

Figure 3. This fixed-wing remote piloted air system has proven successful in upstream operations. Source: BP.

For the moment, RPAS supplier Flylogix, Fareham, U.K., is focusing on offshore methane emissions because of their high priority in the oil and gas industry. “With a range of 4–500 km, the opportunities are significant,” notes business development director Chris Adams. The data are geo-located to a high degree of accuracy, he adds, equipping operators with emission rates from an asset without the cost or risk of mobilizing additional people offshore.

Process plant monitoring by such RPASs is also a possibility. “We would be pleased to talk with operators about what the downstream requirement looks like and how we might be able to help overcome some of the complex challenges of emission monitoring,” says Adams.

Meanwhile, BASF Ludwigshafen, Germany, continues to focus on volatile organic compounds (VOCs) as its main fugitive emissions.

“Although we have no quantified reduction targets, we expect to further decrease our fugitive emissions — based on an already very low level — with the introduction of new TA Luft [air quality] requirements for the tightness of high-integrity equipment such as valves, flanges, pumps, etc.,” states a spokeswoman.

The main tools BASF relies on are FIDs using pre-set emission thresholds. An IR camera often serves as a preliminary detection tool, with a more-precise check with an FID following immediately after any suspicious activity.

“Drones are being tested, but at the moment there is no commercial use of such items,” she adds.

Emerging Technology

Scientists at Nanyang Technological University, Singapore, have developed a prototype device that can identify a range of airborne gases and chemicals instantly. These include sulfur dioxide, carbon dioxide and ppb levels of polycyclic aromatic hydrocarbons.

The new device, which is portable and suitable for rapid deployment, uses a small patch made of a special porous and metallic nanomaterial to first trap gas molecules. Shining a laser light on the gas molecules causes emission of light of a lower energy. Its spectroscopic readout enables quick determination of the chemicals detected. The whole process takes ten seconds to complete. For more details, see “Singapore Researchers Develop Technology That Identifies Airborne Hazards Instantly.”