When extracting CBD oil using solvent-based extraction methods, safety is paramount. Along with making sure the product itself is safe and contaminant-free, employee safety is an important consideration when one considers the flammable nature of extraction solvents.
Fortunately, as CBD manufacturers have developed new ways to extract their oils more effectively, they’ve developed more ways to do it safely. That is where closed-loop extractors come into play.
What Is a Closed-Loop Extractor?
When one uses the terms “closed-loop” or “open-looped” in extraction, they are referring to whether the solvent and mixtures are being exposed to the open air. Open-looped extractors expose materials to the open air. Closed-loop extractors are completely contained. This offers several benefits for extractors:
- Contains flammable fumes
- Allows for higher pressure
- Higher return of solvent
- Greater temperature control
Since these benefits lead to cleaner, purer extracts, it’s to a company’s advantage to understand the basics of using a closed-loop extractor.
Using a Closed-Loop Extractor
Step 1: The Solvent
All closed-loop extractions begin with the solvent the operators are using to extract the oil. This can be butane or propane; however, most companies agree that food-grade ethanol is the safest option for extraction. The solvent is chilled in large tanks, then sent through closed tubing into the compartment where the plant matter is being stored.
Step 2: The Centrifuge
This compartment is referred to as the centrifuge or, occasionally, the material column. As the solvent enters the centrifuge, it helps dissolve the plant matter in order to extract the oils from it. Some centrifuges will also spin to help maximize ethanol recovery afterward.
Step 3: Collection and Filtration
From here, the solvent and oils must be pumped into a separate container, again using completely insulated tubing. This leaves you with hemp crude oil that can be used on its own for topicals. However, for those wanting to create tinctures that users can take by mouth, they will need to be pumped directly into a filtration system to filter out remaining plant matter like chlorophyll.
Closed-loop extraction is the preferred method of plant extraction among CBD professionals, and for good reason. It’s safe, efficient, and produces superior oils for users to enjoy. Here at Cedarstone Industry, we have top-quality stainless steel processing equipment to help support the best companies in the industry.