Hydrocarbon extraction typically employs butane, propane, a blend of both, or DME (Dimethyl Ether) as a solvent for cannabis. Because of their higher bonding capability, hydrocarbons are perhaps the most effective way to extract terpenes from plant matter. With low boiling temperatures and relatively low flash points, the temperature sensitivity of hydrocarbons make them energy efficient for extraction but also highly flammable and dangerous to use. Undetected leaks and a lack of proper ventilation has lead to fatal accidents. Hence in most counties across the country, this form of extraction is either prohibited, or more rarely, requires a license.
In a closed loop hydrocarbon extraction system, plant matter is typically packed into a long cylinder. Liquid hydrocarbon is pumped through the cylinder where it washes over the plant matter and dissolves the terpenes and cannabinoids on it’s way to the bottom. From here the collected solution could also run through an in-line de-waxing process which is essentially another cylinder that chills the solvent to below 22 degrees Fahrenheit and passed through several micron filters to separate out lipids and waxes. The remaining hydrocarbon is then purged from the extract in a heated vacuum to create a clean final product.
Alternatively, after being filtered through the first cylinder, the collected solution can immediately vacuum purged. The oil can then go through an additional process called winterization where low temperature ethanol and sifted through several micron filters to separate out waxes and lipids. Because hydrocarbons rarely dissolves chlorophyll, winterization is rarely employed as a part of this extraction process. Even in-line dewaxing is often skipped since this step can significantly reduce yield. A last variable to note is that if lipids and waxes absolutely need to be removed, winterization is much more thorough than inline dewaxing, but can also result in a less flavorful product since the ethanol can degrade terpenes. In-line dewaxing, while less thorough, maintains more terpenes so that the end product has a better flavor. If in-line dewaxing is used, an additional 30-90 minutes of processing time should be expected.
Comments will be approved before showing up.
Gaskets, seals and O-rings come in so many different types of materials that it can be confusing what kind you should use. Check out this article on 6 of the most common used sanitary gasket materials for food grade processing.