A closed loop system is an environmentally friendly setup used to extract compounds from the cannabis plant. The system is referred to as a “closed loop,” because of the assembly of interconnected equipment used to extract, purify, and collect the cannabis compounds without exposing them to the environment.
The system typically consists of solvent and recovery tanks, a collection vessel, as well as various pumps, filters, and valves. The system prevents the solvents or plant material from exposure to the outside.
Why is closed loop environmentally friendly? Because in addition to not exposing the solvents or plant mixture to the environment, the system is more energy efficient than that of the other system typically used, called the open blasting method. Additionally, the solvent is reused in the closed loop system.
Furthermore, the closed loop is generally safer, allowing for better quality control, with less risk of accidents.
Butane or propane is typically used as the solvent, in turn producing the extracts butane hash oil (BHO) and propane hash oil (PHO).
The methodology works in that the solvents extract the compounds from the plant, by passing through several filters and purging steps, removing the impurities and leftover solvent. The leftover extract, which is now purified, is collected in the vessel, which can be processed further and prepared for sale in various retail products.
Closed loop systems also produce better yields, with higher quality extracts due to the increased control over the process, in turn making the method a more cost-effective option.
For cannabis extractors interested in a more cost effective, safer, more environmentally friendly alternative, closed loop is a great option to consider. That said, extraction in general is not recommended for the home enthusiast unless they have the skills and training to be able to operate the equipment safely to minimize any risk.
