One of the biggest challenges facing growers, processors, and new businesses is learning and acquiring the equipment and skills needed to take plant material and turn it into sellable end products.
There are many different types of equipment out there for a variety of different processes, and it can be confusing to know which types of equipment are actually needed and at what step in the process they are utilized.
This article was written to provide a clear understanding of what equipment is actually needed, as well as what the major steps are in processing plant material for extracts, distillate, and other marketable end products.
Use this article as a framework or “road map” to help you build a successful processing facility – without the overload of information that is often associated with purchasing equipment from a variety of different suppliers.
As always, be mindful that this is not a one-size-fits-all approach and that processing facilities can be very different depending on the amount of material processed and other factors.
Scaling up from a smaller operation to a larger one can be difficult and costly if not done properly. But, using the information provided in this article will allow you to enter the market and be competitive, while also preparing for future growth and expansion.
The 5 Steps of Plant Material Processing
Processing plant material can be broken down into five general steps. Each of these steps has its own degree of difficulty and corresponding sub-procedures. Each step listed here requires specific equipment; without this equipment, it can be extremely difficult or impossible to move to the next step or create your desired end products.
The five steps are as follows:
- Winterization & Filtration
- Solvent Recovery
- Devoltization, Decarboxylation & Distillation
- Isolation & Separation
As you will see, some end products require less equipment to make than others. When determining what type of equipment you may need, we recommend first identifying the end product you are trying to create. Then, you can work backwards to find the specific equipment needed to create your desired end product and how that equipment will fit into the general steps of complete processing.
Extraction Processes & Equipment
The first, and arguably the most important step is the extraction of the desired compounds from the plant material.
Extraction is the step that most people are familiar with.
It is the first step in the entire processing chain, and all other steps are dependent on it. Extraction allows you to remove the essential oils from your plant material. This can be done with a variety of different pieces of equipment, depending on the amount of material you need to process and what end products you are trying to achieve.
For example, let’s say you are trying to make live resin, shatter, or diamonds. These end products can be created using a hydrocarbon extraction system. Hydrocarbon systems use butane, propane, or a mix of these two solvents to extract the essential oil from the plant material. Once the essential oil is recovered from the hydrocarbon system, it is purged using a vacuum oven. These two pieces of equipment are the main items needed if you are trying to make one of the three end products stated above. For some, this is as far as you may need to go but, let’s take this a step farther and look at some specific extraction equipment types.
Hydrocarbon Extraction Systems
As mentioned earlier, hydrocarbon extraction uses butane, propane, or a mix of both solvents to remove the essential oils from the plant material. Other hydrocarbon solvents such as hexane or heptane are utilized sometimes but only on a large or industrial scale operation with a matching sized system. When purchasing a hydrocarbon extraction system, it is important to understand that these are highly flammable and explosive solvents, and that most states require a C1D1 room to house this type of system.
This room would contain preventive/safety systems to contain a possible fire (or explosion), such as a fire suppression system, explosion-proof electrical components, and powerful ventilation systems. Hydrocarbon extraction is a very popular extraction method, so there are many types of systems on the market for you to choose from. It is important to find a system that is certified and peer-reviewed to ensure the safety of your operation and those using the equipment. Generally speaking, hydrocarbon systems are not the largest processing systems on the market, and they are usually only able to process 5-15 lbs per hour of material. But, what they lack in speed, they make up for in quality of output. But, quality of output is also very dependent on the temperature of the extraction. Ensuring that the extraction is done at the coldest possible temperature will allow the user to create the high quality output desired. Purchasing a system with temperature control units included will make this process much easier.
Hydrocarbon extraction systems allow you to create high-quality end products using only the system and a vacuum oven alone. Some examples of these are: live resin, shatter, diamonds, sauce, and other potent essential oil products.
If this is your end goal, then acquiring a quality hydrocarbon extraction system and vacuum purge oven, such as those shown below, should be your first steps.
Hydrocarbon Extraction systems can also be used to create “crude” oil. Crude oil is a common term used in a variety of industries to denote oil that has been extracted but requires further processing steps to accomplish the desired end product.
In this case, hydrocarbon systems can also be a good choice if you are simply looking to produce crude oil to refine and distill later, as long as you can aquire a system that matches your desired production capabilities and throughput.
CO2 Extraction Systems
CO2 Extraction systems are another class of system that can be used on its own to produce viable end products.
CO2 crude oil has become a common cartridge filler in the past few years and has gained some popularity due to its terpene retention. Terpene retention is often achieved through specific operational parameters and allows for a more natural flavor profile in the desired end product. Another benefit of CO2 systems is that they do not require a C1D1 room like hydrocarbon systems, although they do operate at very high pressures so purchasing an ASME certified system is imperative. Other preventive measures should still be utilized within the processing space, such as ventilation and proper system containment, to create a safe working environment for operators. CO2 systems can also be extremely expensive compared to hydrocarbon systems with similar throughput, but their lack of flammable solvents, ease-of-use, and decent throughput capabilities make them an attractive option for many potential processors, as long as the system is properly manufactured and placed in a safe operating area that can contain the high pressure vessels utilized.
CO2 can also produce crude oil at a rate that is acceptable for most operations, although most hydrocarbon systems generally have higher throughput. But, both of these systems have less throughput than an alcohol extraction system comparatively. For most processors, the difference between purchasing CO2 and hydrocarbon systems will be the cost of the system as well as the build-out of the specialized room to house the system. CO2 and hydrocarbon will have comparable throughputs for small to medium processors but don’t usually have the same throughput as alcohol extraction for large or industrial/plant scale operations.
Apeks Supercritical CO2 Extraction System
Alcohol Extraction Systems
Alcohol extraction systems are the third most popular type of system and, as stated above, are often geared towards large-scale or industrial production.
They typically use either ethanol or isopropyl alcohol as the extraction solvent. Alcohol systems, generally speaking, have the highest throughput when it comes to essential oil extraction from plant material. Run times are usually short, and most systems have some level of automation, making them extremely simple to use.
The trade-off here is that alcohol extraction systems require a lot of solvent and must be paired with large solvent recovery systems. Large amounts of solvents can be dangerous if not handled or stored properly; additionally many facilities/jurisdictions may have maximum allowable quantities (MAQs) for solvent storage at a site, thus inhibiting the scale of production. In most situations, a C1D2 room is required for operation of these systems. Although this is not as stringent as C1D1 for hydrocarbon systems, the cost should still be considered when purchasing an alcohol system. Containing any spilt solvent will be the major requirement in this situation as well as ensuring the safety of any operators.
Another important aspect of alcohol extraction is ensuring a cold extraction is performed. This will minimize the amount of post processing needed via minimizing sugars, gums and phospholipids that are removed from the plant during extraction. Gums (like rubber) can be extremely difficult to remove and will hinder further post processing steps. Sugars can also be difficult to remove; which if not removed prior to distillation, can cause an array of issues inside of continuous, wiped/thin film systems. These contaminants may be removed via liquid/liquid extraction – a method that utilizes water to remove polar contaminants from non-polar solutions. Alcohol extracts can also contain high amounts of particulate which must be filtered out prior to any further processing. When it comes to alcohol extraction, this type of system is almost always solely for crude oil production. For this reason, alcohol extraction is usually recommended in situations like industrial hemp processing, where thousands of pounds must be processed efficiently.
Winterization & Filtration
The next step in the process is the refinement of the crude oil that was produced during the extraction stage. The refinement of crude oil is most easily done through a process called winterization.
In the case of CO2 and hydrocarbon crude oil, a solution is created by mixing the oil with a solvent, usually alcohol. With alcohol extraction, the alcohol is already saturated with crude oil, allowing you to skip straight to the winterization step.
The alcohol/oil solution is then chilled to the lowest possible temperatures, anywhere from 0°C to -80°C using a commercial freezer. The lower the temperature, the faster winterization can take place. As the winterized solution chills, fats, waxes, and other inactive compounds will precipitate out of the mixture and become semi-solid. The removal of these fats, waxes, and inactives is crucial to achieving a quality end product. It is also important to note that if you performed an extremely cold extraction, you may be able to skip the winterization process completely.
** Please note: Ai Ultra-Low Freezers ARE NOT EXPLOSION PROOF**
The next step in the winterization process is the removal of these fats/lipids and waxes via filtration. This is generally a very simple step, but it can be extremely time-consuming and messy if the wrong type or size of equipment is used. For most small-to-medium-scale production settings, a porcelain or metal Buchner Funnel system is enough. These are often inexpensive and easy to operate. They can also be “scaled” relatively easily, by adding a second, third, or even fourth funnel. This would allow you to filter larger amounts of solution without experiencing a bottleneck in production.
For larger-scale filtration, industrial filter presses, lenticular, or bag-style filter vessels are used. These systems often use positive displacement pumps instead of vacuum or gravity to move the solution. Regardless of which method you use, once the solution has been fully filtered, the fats/lipids and waxes are then discarded, and the solution will be ready for the next step in the process.
After the crude oil has been fully winterized and filtered, it must be separated from the solvent it is dissolved in. This is done using a solvent recovery system. Solvent recovery systems allow you to recover the solvent (most often alcohol) that was used during the winterization or extraction step.
This solvent can then be re-used, making solvent recovery an essential step in terms of processing as well as cost-cutting. The two most common types of solvent recovery systems are rotary evaporators and falling-film systems.
Most small, medium, and even large-scale processors use rotary evaporators as the main form of solvent recovery. Rotary evaporators have been in use for decades in other industries, and they are specifically made for solvent recovery.
“Rotovaps” are available in a variety of sizes, from 5L table-top models all the way up to 50L, floor-standing models. When deciding on a rotary evaporator system, it is best to think bigger rather than smaller. This will help you maintain production levels when scaling. It is also relatively easy to add a second, third, or fourth rotary evaporator of the same size to increase production volume.
Falling Film Evaporators, on the other hand, are usually much more expensive but can process several times the solvent that even the largest rotary evaporators are capable of.
Falling films are often paired with alcohol extraction systems, because of how much solvent is generated during the extraction process. Falling films are useful for industrial hemp processing, and their high price tag is often matched with an even more impressive recovery rate.
If not accounted for properly, solvent recovery can lead to an unwanted processing bottleneck for many operations. We believe it is wise to carefully analyze your realistic production capacity before purchasing a solvent recovery system.
Degassing: Devolatilization and Decarboxylation
After solvent recovery, the crude oil is almost ready to be distilled and turned into a refined end product. Before this can take place, devolatilization and decarboxylation should occur in order to achieve the most desirable results in distillation. Decarboxylation activates target compounds by releasing carbon dioxide from the non-activated, acidic compounds. Without this imperative step, the compounds will have different, less noticeable effects as an end product. Some end-products do not require decarboxylation – this depends entirely on the desired effect/target market that a company is pursuing. Luckily, decarboxylation and devolatilization may be achieved via the same process.
The crude oil itself will still contain about 1 to 10% solvent after the solvent recovery process. This small amount of solvent must be removed prior to distillation. It may seem like a negligible amount, but distillation systems operate much more efficiently when the crude oil is fully devolatized beforehand. The addition of heat to the mixture will also cause decarboxylation to happen which will activate the desired compounds to allow for full medicinal and recreational effects.
To do this, a simple hot plate device (for small scale operations) is used. Alternatively a reactor system is used for large-scale processing. During the devolatilization and decarboxylation step, the remaining solvent, water, other low boiling point compounds, and carbon dioxide are removed thus the term degassing. This step results in a faster, more stable distillation, a more potent end product, as well as activating the targeted compounds.
Devolatilization and decarboxylation is performed by simply heating the crude oil to just below distillation temperatures, usually between 100° to 140°C. Any remaining non-activated compounds in the crude oil will also be decarbed during distillation. Once this step is completed, the crude oil has been fully prepared and is ready for distillation.
Distillation of the crude oil is the final step for most processors. The distillate created from this process can be used as a cartridge filler or for orally ingested products.
Distillate is highly refined and contains a very high percentage of the target compound, usually between 85 and 97%.
To perform distillation, there are typically two types of systems that are used. The first is the bench top short path system and the second is a wiped/thin film system. Both of these systems are extremely effective for distilling high-boiling-point compounds.
Bench top Short path systems are usually less expensive than thin/wiped film evaporators, making them a more popular choice for most small-to-medium operations. But, bench top short path systems, like our new G3/G3X kits, are still capable of larger volumes while retaining a relatively small footprint.
This makes them attractive for larger operations as a less expensive starting point to begin distilling crude oil. It is also easy to scale your bench top short path system by adding a second, third, or even fourth system to increase production capacity.
Wiped/Thin film evaporator systems, on the other hand, are more expensive. However, they allow for “continuous” distillation as opposed to “batch” distillation with a bench top short path. What this means is that a thin film can be continuously loaded with crude oil without having to stop the system. Please refer to our blog article on thin/wiped film distillation systems for more information.
Batch/bench top short path systems, in contrast, need to be cleaned and refilled after every run. This isn’t necessarily a negative, it just means that more time is spent cleaning and preparing rather than distilling. Some wiped/thin films are also much larger in capacity than bench top short path kits and have extremely high throughputs.
But, with the larger capacity comes a much higher price tag. The final distillate product that is collected from either system is nearly identical, so regardless of which system is utilized, as long as the crude oil is properly prepared, a high potency distillate will be achieved.
Isolation & Separation
For most processors, distillation will be the final step to achieve a sellable end product. But, isolates have gained considerable popularity over the last few years.
Using high-potency distillate and other solvents, an isolation system can take that 85-97% distillate and turn it into a 99% isolate, via precipitation.
This is often in the form of a crystallized substance that can then be powderized, precisely weighed, and then added to capsules, tablets, or other orally ingested products, as well as topicals. This is very similar to what the pharmaceutical industry does to create medicines.
Isolation can be taken even further by utilizing techniques like flash chromatography to isolate small quantities of specific compounds in the crude oil or distillate. A flash system such as the one pictured below is designed for separation of compounds that may not be separable via boiling point in a distillation process. These compounds may be highly sought after for specific effects and medicinal uses.
Because of the complexity of isolation techniques (and the amount of chemistry involved in this step) it is best to consult a technical expert on your end goals and capacity when purchasing an isolation system. Additionally, any flash chromatography system should always be paired with onsite analytics via High Pressure Liquid Chromatography (HPLC) for quick analysis and confirmation of fractions collected through the flash process.
When attempting to enter the market space, it is imperative that you identify what end products you would like to create. This will allow you to see the bigger picture and understand fully what equipment is required to reach your end goal. Additionally, understanding where the market trends are headed for the respective products/compounds is ultimately important in your company’s longevity.
As you are now hopefully aware, all of this equipment is relatively specialized to specific steps or end products. This means that operators and processors need to have a full working understanding of how to make use of each specific piece of equipment. Acquiring the equipment is also best done in a specific order, to minimize costs and maximize production capability.
For example, buying a bench top short path system without having an extractor or rotary evaporator will not be very conducive to making any end product. Many prospective businesses make the mistake of underestimating the process/chemistry knowledge required to operate and efficiently produce products via the aforementioned processing steps. Preparation and knowledge is key to processing success. For more information on specific equipment types or for help building a complete processing solution, please call us at 720-600-2037. We have many years of industry experience and knowledge, and we can help you enter this competitive and rewarding market space.