One person who has been taking a keen interest in the evolution of LDARs is Jim Drago, senior manager, market intelligence, Garlock, Palmyra, N.Y. He says EPA's July 31, 2009, settlement with the Lanxess/Ineos facility in Addyston, Ohio, is the first example of the agency demanding an enhanced LDAR.
"Enhanced LDAR is being imposed when existing LDAR is found not to be working effectively. The most progressive part of an enhanced LDAR program is the demand to use low-leak valves and packings: 100 ppm — as opposed to current 500 ppm — for five years, plus a guarantee and test report from the manufacturer to ensure the target is being met," he notes.
He also has noticed that recent decrees focus particularly on quality programs, repair timing and management of change — although a typical enhanced LDAR program has 14 elements, including: monitoring frequency; leak detection and repair action levels; leak repairs; equipment upgrades, replacement and improvement; training; record keeping; and reporting.
ROLE FOR INFRARED
Drago adds that infrared (IR) cameras (Figure 2) now are accepted as tools to find leaks, in addition to EPA-Method-21 organic vapor analyzers (Figure 3) that were first specified for use in supplemental environmental programs (SEPs) in the late 1990s. "Lo and behold, just over a decade later and they are law, part of standard regulations as an alternative to sniffing. The point here is that they started out as being included in consent decrees, but are now — with time and use — simply part of 'business as usual.'"
One company making good use of IR cameras is LyondellBasell, Houston, which deploys such cameras at its sites in Channelview and La Porte, Texas, and Morris and Tuscola, Ill. The firm adopted the IR camera technology after it proved very effective in ground and aerial surveys.
"The use of IR cameras has enabled us to pinpoint the exact location of leaks that might have remained hidden using traditional fugitive monitoring techniques. In only minutes, an operator can aim, pan and zoom as far as several hundred feet away from an area and check for leaks without leaving his feet. Traditional methods for identifying fugitive emissions required placement of an instrument probe directly on the component, a challenge for components high in a pipe rack," notes the company.
Another advantage of IR cameras is their ability to detect particularly elusive emissions that come from corrosion beneath insulation. Historically, it's been challenging, if not impossible, to pinpoint these leaks because the vapors often exit a considerable distance from the source. The IR camera very easily can detect the source by simply following the trail of the plume.
ConocoPhillips Canada, Calgary, also is a fan of IR. The company, which claims to be the first Canadian firm to use an IR camera to detect fugitive emissions in upstream oil and gas facilities, says the technology rapidly, accurately and safely identifies hydrocarbon gas emissions in realtime: "This has a much higher degree of accuracy compared to conventional methods and has proven to be a cost-effective, efficient and successful method of reducing fugitive emissions," it says.
Drago foresees this possibly becoming another standard technology. "The first demand for fenceline monitoring that I came across was the September 2010 Murphy Oil consent decree when they had to install a similar system as part of a SEP. Maybe in another ten years it will be routine that every site in the U.S. could be required to do the same thing. ConocoPhillips has been routinely using one at its Rodeo refinery near San Francisco for many years. (Its emissions can be seen at http://fenceline.net/fence.php.)"
EPA's May 23, 2012, consent decree with BP North America, Houston, to cut emissions from its Whiting, Ind., refinery requires installation of a fenceline monitoring system as well as publishing the data live on a website.
As a result of LDAR and enhanced LDAR, chemical makers are asking Garlock to provide "best in class" sealing solutions — including product recommendations, training and on-site troubleshooting/failure analysis where required. "In an LDAR program, especially if a chemical plant is given a consent decree, they want training not only for their employees but also for the contractors and valve installers. In gasketing GST is called constantly for consulting."
Garlock's customers are focusing particularly on fugitive emissions from valve stem packing. Some, for instance, are looking into upgrading valve technology for lines carrying high priority volatile organic compounds such as benzene. Emissions from flanges, despite the large numbers of them at most sites, don't seem to be a major problem.
"When we started working on LDAR programs back in 2001, we were repacking all valves in the field that had readings of over 500 ppm. All the new valves that were in the storage yard were sent to a staging area for repack with Garlock low-emission packing. What we see now is that 80% of valves that are chronic leakers or problem valves are being replaced with new valves with low-leak packing," notes Drago.
Seán Ottewell is Chemical Processing's Editor at Large. You can e-mail him at email@example.com