Distillation is a method for separating compounds based on their unique physical properties, like melting point, boiling point, crystallization, etc. One of the most common forms of distillation is by using boiling points. When the compounds’ molecules’ are heat-sensitive, processors use Short-Path Distillation to separate them from one another.
Marijuana and hemp processors take advantage of short-path distillation’s ability to separate compounds in order to purify and isolate cannabinoids in a cannabis extract. The result is a high-purity, superior quality concentrate that can be sold on its own or further processed into a variety of end products.
Short Path Distillation
Short path distillation, also referred to as fractional distillation, produces high-quality cannabis distillate, though the process is limited in both scalability and production capacity. During the short-path process, a boiling flask is used to heat crude oil and the oil is agitated with a magnetic stirrer. The compounds are separated in the oil using heat until they transform into vapor. The vaporized compounds rise up and then are chilled back to a liquid using a condensing coil.
Cannabis oil compounds are separated into 3 different “fractions” (main, heads, tails), collected at the different temperature points in the distillation process. As the temperature rises, a new compound fraction is evaporated, re-condensed and then goes into a receiving flask.
Main Fraction: contains the THC and CBD cannabinoids
Heads Fraction: contains the terpenes and other high volatiles
Tails Fraction: contains other high boiling point cannabinoids
When distillation is used as a purification process for CBD and THC oils, it requires very closely controlled temperatures, pressure levels and material input volume, so that the product is processed in a way that results in the highest possible purity and doesn’t damage or degrade the cannabinoids being collected.
Short-path distillation requires an experienced laboratory team. Since it’s somewhat affordable, though limited in scale and production volume, it can become a cost-effective entry point into the hemp and marijuana extraction industry.
So why should a marijuana or hemp processor choose short-path distillation?
- Bench-top system with a relatively small footprint
- It results in highly-concentrated CBD and THC distillates
- A short-path distillation system is generally lower in cost than other available systems like a wiped film or thin film distillation system.
Wiped Film Distillation
It is worth explaining, because it is often confused, that the technique of wiped film distillation is a form of short-path distillation. Sometimes it is also referred to as “thin film” or even “rolled film” distillation. This technique is simple, effective and great for larger scale operations with high throughput needs. The difference is the continuous feed aspect of wiped film.
Crude oil is added to a heated cylinder on a rotation plate, while “wipers” create a thin film on the surface of the heated evaporator. This film is heated to a specific temperature to create a vapor. The vapor is then cooled and collected on a condenser coil and the desired compound has been “distilled.”
The operator can optimize the material feed rate, the vacuum level and the temperature during wiped film distillation, in order to yield the specific desired distillate composition. The major advantages of wiped-film distillation are high productivity, ability to run in continuous mode, and easy-to-use controls allowing for a repeatable process.
Getting Started With Short Path Distillation
The future of the cannabis business is limitless. The ability to process cannabis plant material into distillates and other purified cannabis components is an excellent way to grow your hemp or marijuana operation with product diversification. If you are looking to make a variety of products like edibles, vape cartridges, oils, lotions or pills, you will need a distillation system.
As the global leader in cannabis extraction equipment, we’re experts in extraction and distillation technology. We are a distributor of short path and wiped film distillation systems and also offer on-site training programs for our clients using a mixture of classroom and hands-on instruction.