Temperature Control for CBD/THC Extraction and Distillation
The legalization of the hemp cannabis derivative CBD and of marijuana and its THC derivative for medical and recreational purposes in many US states and all of Canada has led to significant economic growth in the CBD/THC extraction and distillation equipment sector. Many of the manufacturers of these two categories of equipment have been in business for a number of years, and the processes used for extraction and distillation have been refined over decades since they are used to extract and purify many different organic substances, chemical, petrochemical and alcoholic beverages. However, hemp and marijuana have their own unique characteristics, and the processes to extract and purify CBD and THC from their respective plant sources are still being fine-tuned by processors and original equipment manufacturers (OEMs).
There are quite a few different approaches to extraction and distillation of CBD/THC products, and each has certain benefits as well as some less desirable side effects; but they all have in common these parameters that need to be controlled: temperature, pressure or vacuum, source material throughput volume, and for extraction, solvent feed rate.
Extraction Process – Temperature control considerations
Current extraction processes include CO2, butane or propane, and ethanol. In each of these methods, the extraction agent is cooled down to temperatures that can reach -80°C (-176°F) and then compressed until it is liquefied. The temperature reduction is achieved using a chiller, which can be a standard piece of equipment or a custom unit designed to meet unique temperature profile requirements.
In commercial systems, extraction is typically performed in a jacketed vessel. Water, oil or other liquids are circulated within the jacket by a temperature control unit (TCU) which maintains consistent vessel wall and extraction chamber temperatures.
Temperature control is necessary throughout all the steps in the process, but precise extraction chamber temperature control is absolutely essential to managing final product quality and characteristics. This high level of control must also be replicable from one batch to another and in fact on a continuing basis over a large number of batches. Controlling temperature to within .275°C (.5 °F) is a standard that permits a consistent finished product. It is also important to note that repeatability, in addition to accuracy is extremely important for producers as it allows them to replicate the process over time, and thus insure consistent product quality.
For example, increasing the extraction temperature from the initial agent temperature can:
- decrease the concentration of terpenoids in the extract
- risk denaturing the final CBD/THC product
- increase wax/resin extraction and overall volume, but yield a lower quality product
Similarly, decreasing extraction temperature can lead to:
- increase the concentration of oil in the extract
- reduce the wax proportion of the extract
For these reasons, having equipment that is capable of consistent and accurate temperature control is very important to producers; and as there is demand for many variations of this extraction process’ final product, chilling equipment and temperature control units with high precision, closed loop controls are critical.
Once the extraction process is complete a processor is left with “crude extract” that is 55-75% cannabinoid and that may in some instances, be sold without any further processing. For the majority of processors however, further separation of the remaining elements is necessary to obtain fully purified, high value CBD/THC oil.
The next step in the purification process is to remove waxes by cooling the extract down to approximately -20°C (-4°F) in a chiller-driven jacketed vessel. This “winterization” process precipitates some of the undesired elements out of the solution which after filtering, leaves oil made up of cannabinoids, chlorophyll and terpenes. Decarboxylation is an important step that may be performed either before or after the winterization process. It is used to activate CBD/THC components and is accomplished by carefully heating an extracted solution to release the carboxyl ring group (COOH).
Distillation Process – Temperature control consideration
A distillation process is then conducted to complete the separation of the remaining elements and produce the purest possible CBD or THC oil. It is worth noting that even though a source material has been winterized, as much as 40% of the remaining feedstock may consist of undesirable materials. Also, in the case of ethanol extraction, ethanol must then be evaporated to separate it from CBD/THC components.
As in the extraction process, the distillation process that is used to fully purify CBD/THC oils requires closely controlled temperature, pressure and source material feed rates to ensure that the necessary interactions produce a high-quality finished product with characteristics that generate the highest possible value.
The most common pieces of equipment are wiped film, molecular short-path stills. In this approach, the feedstock of oil is fed into a jacketed vessel that is often heated with an oil circulating TCU to achieve temperatures up to 343°C (650°F), though the typical distillation temperature range is 130 -180°C (266-356°F). In these systems, the feed stock is distributed on the evaporation chamber wall with a special wiper. The resulting thin film allows the more volatile terpenes to evaporate through the top of the chamber into their own external collection vessel, while the CBD/THC is collected along a TCU controlled central condenser unit which is cooler (typically 60-70°C / 140-158°F) than the evaporation chamber and serves to attract the cannabinoid vapor. The final step in the process is solvent removal, which is accomplished in a separate, external cold trap, which is also temperature controlled with a chiller.
Certain OEMs offer wiped film molecular short-path distilling equipment that integrates the removal of heavier materials directly into their distilling process. In this instance, chlorophyll, waxes and other heavier residue (up to 40% of the feed stock) descend the outer wall of the distillation vessel and are collected in their designated container.
In certain cases, a final separation step is taken to separate THC from CBD. Crystallization is a common method. A reactor vessel is filled with feedstock and a solvent which is chilled slowly from 60°C to -20°C. A slurry results and that is transferred to a Nutsche filter dryer to produce pure, dried crystals. The Nutsche filter is a jacketed vessel whose temperature is controlled with a circulating hot oil unit. The process results in a 98% or higher purity of the CBD or THC product.
Delta T Systems – Your partner in Pure Temperature Control
Delta T Systems has worked with extraction and distillation equipment manufacturers as well as end user engineering groups for over 25 years. The products we offer are designed to specifically address customers’ production needs. That is why so many customers return to us and choose our equipment over and over again as their production needs expand. We offer industry leading design, efficiency and service.
Delta T Systems has developed a broad range of industry leading product features and capabilities that make our TCUs and chillers the best on the market:
- Capabilities from 1-60 tons (higher capacities offered as custom designs)
- Variable speed design that can cut energy usage up to 50%
- Standard operating range from -18°C to 27°C (0°F to 80°F)
- Highly accurate closed loop temperature control to .275°C (.5°F)
- Data logging with remote control and analysis tools
- Industry 4.0 ready
- Long life heat exchange materials and low maintenance design
Temperature Control Units (TCUs)
- Water Circulating Temperature Control Units (TCU) will perform in processes up to 300°F (149°C)
- ¾ to 7 ½ HP Pump, 25 to 150 GPM
- 9 to 144 KW Low Watt Density Heater
- 149°C (300°F) Fluid Operating Temperature
- 6, 12, 18, 24 or 36 KW Heaters, or special designs up to 360 KW
- Maximum Operation Temperature up to 343°C (650°F)
- 10 to 150 GPM Pumping Capacity
- Heating Only or Heating with Cooling Capabilities
Custom engineered product development and designed solutions are our specialty
- Made to address customers’ unique needs
- Custom design chillers and TCUs available for greater capacities
For CBD or THC extraction and distillation temperature control, Delta T Systems has the experience, expertise and capability to give processors and OEM equipment manufacturers standard or custom equipment to meet all aspects of the process’ requirements. All systems are designed for process repeatability. Our equipment lowers production costs, improves temperature accuracy, and delivers long lived quality and ease of maintainability.
Dan Brandenburg, Director of Sales & Marketing at Delta T Systems can be contacted for more information (262) 628-0331.
© 2022 Delta T Systems. All rights reserved.
2171 Highway 175 • Richfield, Wisconsin 53076
262.628.0331 • 800.733.4204 • fax: 262.628.0332 Email
How To Make Canna Oil For Edibles
Making cannabis edibles at home is easier than people might think. If you have shopped at a cannabis dispensary, then you know firsthand that cannabis edibles can be expensive, especially if you need to purchase them on a regular basis. Medical cannabis patients often need to consume more cannabis than other people to treat their conditions and ailments, and look to edibles for relief, which can result in sticker shock. That’s why it’s a good idea to know how to make canna oil for yourself.
Many people prefer to consume cannabis via edibles as opposed to other consumption methods because the consumer/patient does not need to inhale anything into their lungs when they are ingesting cannabis from food.
For some patients, inhaling cannabis smoke or vapor is not an option as a direct result of the medical condition from which they suffer. Other patients may rely on edibles instead of alternative non-smoking methods such as topicals because edibles provide more relief.
Whatever the case may be, you should give strong consideration to making your own edibles. It can be a fun experience in addition to helping you save money.
Every cannabis edible starts with creating something to infuse the edible with. Cannabis-infused butter is a very popular route, although some people do not like to consume dairy either because they are lactose intolerant, vegan, or various other reasons.
Cannabis oil is a great alternative to butter, and is often far healthier than cannabis butter. It can also be used for more savory recipes where butter is not the ideal ingredient.
We will discuss below the factors to consider, as well as a recipe for how to make cannabis oil.
What’s The Best Oil To Use To Make Cannabis Oil?
When considering which oil to use to infuse with cannabis, it’s really up to personal preference. When oil is mixed with crushed, decarboxylated cannabis plant matter and heat is applied, the cannabinoids and terpenes will bond with the oil.
Olive oil is a very popular oil to use, as is coconut oil. The main thing to consider, beyond just taste, is the consistency of the final product. Cannabis-infused olive oil will be thin and runny, while coconut oil will have a better chance of remaining solid while at room temperature.
Coconut oil is a great option because it can also serve a dual purpose as a topical in addition to being used as an ingredient for cannabis edible recipes.
Cost is a big factor, in that not all oils cost the same amount of money. If you only have one type of oil that you can afford and it’s easily available in your area, it will work with decarbed cannabis flower just the same as any other type of cooking oil.
Easy Cannabis Oil Recipe
Whether you want to learn how to make canna oil in big or small batches, this easy recipe works. You can double or triple the amount of cannabis involved as long as you maintain the 1:1 cannabis-to-oil ratio.
For that matter, if you want to make a smaller batch, possibly because you simply don’t have a full cup of cannabis flower to use, the 1:1 approach works in those situations as well.
A larger batch will obviously require a larger slow cooker or crock pot. Also, the cleanup duty afterward will be greater, a larger container or more containers will be needed to store the final product, and it is more time consuming during the cheesecloth-phase of the process.
Equipment you will need:
- 1 cup of cannabis flower
- 1 cup of oil
- Cookie sheet
- Slow cooker
- Container to store the finished product
Step 1 — The first thing you will want to do is grind the cannabis flower. After you have the cannabis flower ground up, you will want to decarboxylate it. Decarboxylation activates some of the cannabinoids in the flower, and helps ensure the preparer gets the most out of the cannabis flower used. It’s very easy to do — place the ground cannabis on a cookie sheet and bake it in an oven at 260 degrees Fahrenheit for 45 minutes.
Step 2 — Place the decarbed flower into a slow cooker with the oil and let it go for 6-8 hours, stirring occasionally to mix it around. Keep in mind, wherever you open the slow cooker to stir the mixture around, it is going to smell quite a bit, so do this by an open window or well-ventilated area. The longer end of the timeframe is preferred, however, it’s really up to how much time you have. The longer you let it simmer, the more time the cannabinoids and terpenes will have to bond to the oil. Hypothetically, you could let it simmer for 30 minutes and it will provide some level of usefulness, however, it will be more effective if you let it go for 8 hours.
Step 3 — Scoop the mixture out of the slow cooker and run it through the cheesecloth to separate the plant material from the oil. You will not want to do it immediately because the mixture will be extremely hot. Conversely, you also don’t want to wait for it to become room temperature, because it will be harder to separate the oil from the plant material. Waiting about 30 minutes is a good strategy, although it’s situation-specific, so proceed with caution to avoid getting burnt. Letting the mixture drip through the cheesecloth into a container or multiple containers is all that is left other than cleanup duty. A glass mason jar is a great option for storage.
Other Factors To Consider
Potency: One of the biggest factors to consider when making cannabis oil is potency or finding the ideal dose. Different consumers and patients have different tolerance levels and needs.
Novice and people who are starting to consume cannabis again after a long hiatus will want to stick with something that is less potent than a frequent consumer or cannabis patient who needs extra-strength oil to treat their condition(s).
The type of cannabis flower used will play a big role in this. Specifically, the amount of THC in the flower. If you want to have a lower potency, use a flower that is lower in THC, and, of course, if you want something stronger, use something with more THC.
If you are a novice and the final product is too potent, you can always dilute it by adding more non-infused cannabis oil to the finished product to make it less potent.
If you are on the opposite end of the spectrum, keep in mind that there’s not really a way to make the final product more potent.
Storage: Another major factor to consider is storage. After all, the finished cannabis-infused oil is a food product, so you will want to keep it refrigerated. That is particularly important to keep in mind if you are making a large batch.
Plan ahead to ensure you have enough space in your refrigerator. The last thing you want to do is exert a lot of time and use a lot of resources just to be scrambling at the end of the process to find a place to put it all.
If you miscalculate and end up having too much, you can always make edibles quickly to help clear up space in your fridge, although, you are kind of just kicking the can down the road because those edibles will then need to be stored fairly quickly.
Planning ahead by knowing which cannabis-infused edible recipes call for canna oil is something else to keep in mind. You don’t want to make a small batch of cannabis oil just to later find out that you should have made more.
Do your research, make a plan of attack before you start, and get after it. Happy baking!