Oily Messes, Continuous Use, and Why it’s Important to Change the Fluids in your Engines and Vacuum Pumps
There are several different processes that cannabis extractions need vacuum pumps for. One is in the extraction unit itself, where changes in pressure help move solvent from one chamber to the next. A vacuum can also be used to purge residual solvents and moisture from the crude extract. Depending on the specific extract being made, a vacuum oven can be used to decarboxy late the acidic cannabinoid species into their activated form, making them ready for consumption. Finally, the post-processing of vape oil such as in distillation and rotary evaporation requires the use of vacuums as well.
Regardless of which phase in the extraction process we discuss, there are essentially two main functions of a vacuum pump: either enforcing a vacuum to act as a chemical scrubber for removing undesirable small molecules, or creating a low pressure environment to facilitate the evaporation of large molecules in mild thermal conditions.
There are a number of different vacuum pumps currently in use by cannabis extraction facilities, each with their pros and cons. JB Industries discusses the importance of changing the vacuum pump oil often.
“The proper oil in a vacuum pump acts as a blotter and absorbs all of the moisture and non-condensables. As the oil becomes saturated with these contaminants, the efficiency of the pump is dramatically reduced. Maintaining clean oil in the pump ensures that the pump will operate at peak efficiency and prolong its life.”
And you can’t just use any old oil. Vacuum pumps require a specific, non-detergent oil that can act as an effective chemical scrub for long periods of time. You also want an oil that gives appropriate indication when it has become contaminated, such as becoming “cloudy” or “milky”.
One important thing to note is that, when changing the oil in your pumps, the temperature of the unit must be reasonably warm/hot, and not just cold after having the engine sitting idle overnight. The reason is that those elements which are dissolved in the hot oil can either precipitate out of solution or partition into a separate phase layer as the temperature drops. If you change the oil on a cold machine, those impurities will get left behind. As the new, pristine oil gets phased in, it will quickly absorb those leftover residues, dramatically reducing its lifetime.
Maintaining clean oil in your vacuum pumps is just another important step in the overall operating procedures necessary to make sure that your facility is producing clean, crisp, and high-quality extracts at all times.