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Meet EPA Regulations Head-On with the qMix RealTime Flare Measurement System

May 27, 2021

We are excited to share our latest video, qMix RealTime Flare Measurement System-How it Works, especially if tightening EPA regulations are on your mind.

Last month, the U.S. Senate voted to overturn relaxed requirements for methane emissions, and the U.S. government has begun to strongly enforce previously approved rules. So accurate flare gas measurement is more critical than ever, however, meeting these regulations is easier said than done.

The EPA Refinery Sector Rule 40 CFR 63 requires flow measurement data on 20% of reading at velocities from 0.1 to 1 ft/s and 5% of reading greater than 1 ft/s. For plant engineers in the field, this is a very challenging application due to several factors:

  • Very high turndown from 0.1 fps to 1000 fps during an emergency shutdown

  • Constantly changing flare gas compositions

  • Very low pressure drop (5 psig)

  • Asymmetric flow profile, stratification, turbulence, pulsating flow (60” pipe header)

Multipath ultrasonic flow meters, traditionally the meter of choice for reporting EPA data, are now an unable to successful meet the low end of these regulations:

  1. Most of the installed base of ultrasonic meters have been calibrated to 1 fps prior to the new rule

  2. Additionally, very low velocity is difficult for transit time due to small change in time

  3. CO2, H2 attenuate the signal, so ultrasonic meters cannot read low flows for these common flare gases

  4. Stratification causes reflection/refraction at the layer

  5. Turbulence reduces signal strength so the reading is not reliable.

However, Sierra’s QuadraTherm qMix RealTime Flare Measurement System (FMS) meets this EPA regulation head-on and offers you the perfect solution to comply with EPA Refinery Sector Rule 40 CFR 63 rule which requires refineries to measure and report flare gas measurement at low flow rates as low as 0.1 fps (0.03 smps) where traditional multi-path ultrasonic flow meters can’t operate.

qMix RealTime Flare Measurement System – How it Works

The qMix RealTime Flare Measurement System (FMS):

  • Delivers real-time flare gas flow measurement to accurately measure flows down to 0.1 sfps

  • Meets full range of EPA rule 40 CFR 63 down to 0.1 sfps (0.03 smps) where ultrasonic meters can’t operate

  • qMix RealTime app connects, reads, and updates new flare gas composition from a GC- real-time, no recalibration needed

  • Is easy to install with current ultrasonic flow meters- no process shutdown

  • Highest Accuracy: +/-0.5% of reading (inline); +/-0.75% of reading (insertion)

  • Handles upset conditions at ultra-high flows with wide turndown of 1000:1

The bottom line, you have a tool to compliance with emission monitoring rules. Watch Video to Learn More.

Learn more about qMix RealTime FMS, by downloading the “Solving The Flare Gas EPA Compliance Challenge with Game-Changing qMix RealTime Flare Measurement System (FMS)” application tech guide.

Video created by Sierra Graphic Designer Jose Estevez produced by Erica Giannini.


Maryadine Washington, Mar-Com Manager
Written By:
Maryadine Washington, Mar-Com Manager
Sierra Instruments

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