Definition - What does Closed-Loop Extraction mean?
A closed-loop extraction system is similar to an open-butane run. However, unlike butane extraction, the solvent is sealed off from any air.
The closed-loop extraction process is not new and has been used for decades to extract essential oils for things like perfume and food additives. It has only been in recent years that it has become popular in the cannabis industry.
The product created utilizing a closed-loop extraction system is cleaner. It is also somewhat safer to utilize than an open extraction method. Closed-loop extraction systems have become the norm for commercial and medicinal facilities.
Hydrolife explains Closed-Loop Extraction
A closed-loop system features a large tank with an attached tube, a recovery tank, a refrigerant scale, a refrigerant pump, and a recovery pump. To create butane hash oil (BHO) using a closed-loop system, an additional pump and recovery tank is also needed to create a vacuum oven.
The additional equipment for BHO is to purge the butane from the cannabis concentrate. A closed-loop system operates by packing the tube with fresh cannabis. A pressurized solvent is then attached to the cannabis-filled tube. Various valves and clamps help ensure that the solvent remains pressurized during the process.
The solvent is allowed to pass through the cannabis so the cannabinoids and THC are pulled from the plant material. The concentrated oil is collected in a recovery tank. Although not without risk, a closed-loop extraction system is safer because flammable solvents are confined and cannot leak out to cause a possible explosion.
This is beneficial for pressurized liquids that become gaseous without pressure. With a closed-loop extraction system, chemical solvents can be reused, which saves money.