How To Optimize Your Fugitive Emissions Plan in Edmonton Refineries

Fugitive emissions are the bane of any refinery process. Releasing methane contributes to intensifying climate change effects and is twenty to forty times more effective at trapping heat than an equal amount of carbon dioxide over a hundred-year period. While non-toxic, methane in high enough concentrations can cause asphyxiation and becomes flammable in air mixtures beginning at 5.4% volume. Under MERR, an individual or corporation found noncompliant with Directives 017 and 060 is liable for fines up to $50,000 and $500,000, respectively.

The oil and gas industry is responsible for 44% of Canada’s methane emissions, and in Alberta, this value is over 70%. To slash methane emissions 40-45% to 2012 levels per the Pan-Canadian Framework on Clean Growth and Climate Change, every step of the refinery process must be evaluated and updated with state-of-the-art equipment to seal, mitigate, and detect leaks. For any fugitive emission plan, the best tools will be leak detection services, hose evaluations, and emission-reducing components.

New Regulations for an Existing Fugitive Emission Plan

Three regulations to identify, analyze, and resolve fugitive emissions have already gone into effect in 2020: an upper limit on compressor venting, leak inspection, and a ban on venting for completed wells via hydraulic fracture. Two more regulations, venting limits on general facilities and pneumatic devices, are set to go into effect on January 1st, 2023. With slightly over a year to begin complying with stricter standards, here’s a noncomprehensive list of possible fugitive emission sources to consider:

• Venting of casing heads
• Flash emissions from storage tanks
• Well completions, blowdowns, and workovers
• Compressor rod packing
• Venting from reboilers
• Plant leaks
• Pneumatic devices
• Venting of gas for maintenance/repair
• Pipeline leaks
• Seal oil degassing
• Leaks from mains and service lines
• Leaks at metering stations
• Pipeline blowdowns

Valves as a Major Contributor to Fugitive Emissions

Sixty percent of all fugitive emissions can be attributed to valve stem leaks, and reviewing the potential thousands of valves over the refinery process is a daunting task. One important distinction in evaluating valves is their state of actuation: occasional or continuous. Visual inspection for damage to the gland studs or stem can identify valves on the verge of mechanical failure; the failing studs or stem can pierce the packing, causing leakage. Different temperatures, pressures, and media could also be a source of rapid wear; in general, the more often a valve is operated, the faster it is likely to wear. Furthermore, different valves will have different characteristics in valve actuation force, such as axial compression to radial compression ratio, friction, and adjustability. Note that valves with rising stems are likely to leak more frequently than quarter-turn valves.

Valves need not only be mechanically sound but also properly installed to combat fugitive emissions. Correct installations will provide additional compression to the packing, further lowering emissions and lengthening the valve’s service life.

An Overlooked Source for Fugitive Emissions

Hoses and other open-ended lines account for 5-10% of fugitive emissions on the high-end of estimations. This may seem insignificant compared to valves, but it is important to remember that any opportunity to reduce emissions saves money by conserving a valuable fuel source and reducing the buildup of potent greenhouse gas in the atmosphere. Given that leaks from hoses often occur in direct contact with the atmosphere, these fugitive emissions have a chance to resolve into a highly flammable mixture. Properly functioning equipment may undergo leakage when techniques are incorrectly applied to the line, such as a block and bleed procedure.

Maintaining Seal Support Systems to Combat Fugitive Emissions

When considering seal support systems and their possible contribution to fugitive emissions, the separate maintenance requirements of static and mechanical seals will come into play. Static seals involve not only the gasket itself but the joint at which it is affixed. In joint failure, some aspect of the flange-fastener-gasket system fails. Common causes of failure include incorrect tightening or application of fasteners, reuse or incorrect gasket application, and user error in installation. These failure modes will manifest physically as corrosion, stress-cracking corrosion, fatigue, and self-loosening seals.

Mechanical seals evolved as an industry response to greater demands in emission standards. While most low-emission regulations can be covered by mechanical seals, seal-less pump drive options do exist for the most exacting emission conditions at a tradeoff of pump efficiency. Generally, seal-less systems see utilization in a lock-and-key manner: a highly specific application, but the most overall efficient for that particular process.

Reinforce Your Fugitive Emission Plan with Edmonton Valve & Fitting

Edmonton Valve & Fitting offers a plethora of products and services to keep your Edmonton refinery running efficiently while adhering to new and evolving fugitive emission standards. For the needs of today and tomorrow, our Field Advisors can bring your operation’s fugitive emission plan to fruition.