Measuring vent and greenhouse gas emissions

Oil and gas well leaks are responsible for introducing a significant amount of methane into the atmosphere. In order to protect the environment and comply with regulatory agencies, it is critical to accurately measure these greenhouse gas emissions.

Challenge: Measuring leaks at near-atmospheric pressures in remote locations

There are several factors that make it measuring vent and greenhouse gas emissions a bit challenging:

1. Oil and gas wells are often remote and hard to access.
2. Leaks can occur in many places throughout a production site.
3. They often occur at near-atmospheric pressures, which makes them difficult to detect and measure with accuracy.
4. Because of the flammable nature of natural gas, leaks are hazardous.

Solution: Portable, low pressure drop mass flow meters

Alicat’s portable Whisper-Series gas flow meters provide direction solutions to each of the four challenges listed above:

1. Usable in remote locations: Take these meters right to the source of the leak and insert them inline to validate flow rates with no need for external power, wiring, or integration with PLCs.
2. Compatible with varying flow & leak rates: A wide operating range (0.01% to 100% of full scale) ensures a single meter can accurately measure multiple wells with greatly varying flow or leak rates.
3. Operates at near-atmospheric pressures: Whisper-Series devices introduce minimal pressure drop into the flow lines, suiting them for applications at near-atmospheric pressures.
4. Certified for hazardous environments: Meters can be customized to meet Class I Division 2 enclosure standards, and can be constructed of 316L stainless steel and appropriate wetted materials to avoid damage by the aggressive gases found in un-combusted natural gas compositions.

An added bonus is that these meters are multi-variate, able to simultaneously measure mass flow, volumetric flow, gas pressure, and gas temperature.

Conclusion

The gas components of emissions from natural gas wells will vary with the location and region in which the well is located, and continuously measuring emission flow rates and volumes can help liquid natural gas producers monitor and document changes over time. Alicat devices have been built directly into gas well skids to serve this purpose. These meters are used by United States governmental agencies, Alberta Energy Regulator, KimPro Energy, and BC Oil and Gas in Canada use Alicat meters for leak detection at oil and gas well sites. Read the KimPro case study. Additionally, Wend Energy of Colorado uses Alicat flow meters to measure changes in emissions from storage tanks (another source of methane emissions) before and after they deployed their innovative vapor lock technology.