A VMA Technical Seminar Presentation: Leak Detection and Repair

As one of the consultants working for NEIC in Denver, CO, Garing, a chemical engineer, provides LDAR (leak detection and repair) services in some of the largest, most complex plants in the world. It’s a job he’s had since the center opened in 1989. With a state-of-the-art lab, he said NEIC is “kind of like the NCIS for the EPA!”

Garing explained that all the rules the agency enforces “are about keeping the stuff in the pipe!” To do this, the center’s inspectors monitor valves, flanges, connectors, compressors and pumps. Monitoring frequencies range from monthly to quarterly, semi-annually… all the way up to eight years, he said, and while there is a lot of variation “typically, 90% of things are monitored on a quarterly basis.”

Recordkeeping is also an enormous task. For instance, there might be 20,000 valves in a typical refinery and as many as a half-million components that need monitoring, Garing said. And, of course, records must be kept on every one of those components.

Most enforcement actions that take place are civil; in truth there are very few criminal cases, he said, but it has happened. Contractors are usually hired to do the monitoring and typically not well paid—and that opens the door to fraud. Garing discussed a case where a contractor set up a scam to make it appear as if he was in the plant monitoring all the valves every day, while he was actually off site—he faced criminal charges.

Method 21

Garing explained “Method 21,” which he called “the heart of the whole leak inspection process… to make sure components aren’t leaking.” Factors include establishing leak definition, calibration and monitoring locations. For instance, you have to figure out how many people you need to monitor valves; if each one takes a couple of minutes, and there are 400 valves… well, “that’s a LOT of people required to do this each day.”

The leak definition that most use for valves is 500 ppm, he said, and “the leak detection instrument costs about $10,000, plus you have to have data records plus someone to look after this huge database.”

One of the reasons that an agency like NEIC is needed is to verify what the company reports vs. what is actually occurring. Garing showed a chart with the results reported by eight different refineries, compared to what NEIC detected. In every instance the company reported less FEs, and in some instances, the results were vastly different.

Refinery-wide comparitive monitoring results:

Garing says he and his colleagues expect leakage of about 1%, and while “the individual leaks are small, when you add up all these small leaks, they are significant.”

Still, progress has been made in the fight against emissions. In describing the evolution of fugitive emissions, Garing said when he first started inspections back in the mid 1970s (while working for an oil company), he was surprised by how many valves were leaking--between 5 to 10%. Now fugitive emissions are in the range of 1 to 5%. "It's just amazing how things have changed from an environmental perspective during the last 30 or 40 years," he said.

A global impact

This is mighty important work when you consider that many refineries outside of the U.S. and Canada operate without any kind of environmental regulations. Thanks to NEIC, we can all breathe a little easier.

Judy Tibbs is editor-in-chief of Valve Magazine. Reach her at jtibbs@vma.org.

EPA INFORMATION SOURCES:

Enforcement Alert

http://www.epa.gov/compliance/resources/newsletters/civil/enfalert/emissions.pdf

Leak Detection and Repair: A Best Practices Guide

http://www.epa.gov/compliance/resources/publications/assistance/ldarguide.pdf

Ineos ABS USA/Lanxess Clean Air Act Settlement

http://www.epa.gov/compliance/resources/cases/civil/caa/ineos-lanxess.html

Hovensa LLC, Clean Air Act Settlement

http://www.epa.gov/compliance/resources/cases/civil/caa/hovensa.html

Equistar Chemicals Settlement

http://www.epa.gov/compliance/resources/cases/civil/mm/equistarchemicals.html