4 Key Things About Supercritical CO2 Pumps

The pumping technology of your extractor deserves your toughest scrutiny

  1. Does it pump gas or liquid? Pumping high density liquid CO2 might be more difficult to design and engineer, with its need for temperature management, but it is superior for consistent throughput and efficient use of energy.
  2. How does it specify flow (mL or grams)? Rating a system’s flow rate in terms of grams, in other words mass, is the only true way to describe how much CO2 you’re flowing, which leads to a more meaningful measure of throughput.
  3. Does it have a mass flow meter? A Coriolis flow meter, a device that uses density to measure mass flow, is the only way to give accurate feedback for potential buyers to gauge throughput. 
  4. Can it manage temperatures to ensure CO2 remains in liquid state throughout the run? If the CO2 is not kept cold enough, the pump may cavitate, flashing CO2 back to gas during pumping, and creating a choppy flow profile, channeling, system instabilities, and significantly reduced flow.

Green Mill Supercritical systems are the only extractors
with a pump that passes all 4 parts of the test

  1. 4-piston, liquid displacement

  2. True 500 grams per minute flow (beware of false or unverifiable claims)

  3. Coriolis flow meter installed

  4. Extensive temperature management

SFE Pro Complete Video Walk-Through