CBG Biotech Blog

Everything You Need to Know About Cannabis Oil Extraction Systems

June 9, 2023 / by Brad Kovach

Understanding the Basics  

If you are new to the Cannabis industry you may or may not be familiar with the journey of a cannabis plant through an extraction facility. There are a variety of methods – from solvent-based extraction to the use of steam distillation, liquid hydrocarbon and supercritical CO2 – that can carefully extract cannabinoids from the plant biomass.  

In this article we will primarily focus on the extraction, purification and distillation process. CBG Biotech’s CannaTrue™ Extraction, Purification and Distillation (EPD) System is a great example of how an EPD system works. First let’s talk about the key features of the EPD system.


CannaTrue™ EPD System  

The CannaTrue™ EPD System is composed of three different modules – Extraction, Purification and Distillation – designed to process and purify essential oils and help capture the desired cannabinoids from cannabis and hemp. We offer this to customers as a turnkey and automated solution that extracts the oil out of Cannabis plant material using cold ethanol.  

Now let's break down the extraction process. Let me tell you what you need to know about Cannabis extraction. 

How to Use an Extraction System 

The purpose of the EPD system is to extract cannabinoids from the biomass (including flower, stem and processed material) to yield an essential oil concentrate using cold high-purity ethanol. The system will then purify the concentrate and then remove the ethanol from the cannabis oil so that the ethanol can be used again in future extractions.  

The first step is to wash the plant material with ethanol that's chilled down below negative 40 degrees Celsius. Ideally, we process frozen biomass at negative 45 degrees Celsius so we are assured that the temperature will remain below negative 40 degrees Celsius. Processing at this temperature will provide for a fully winterized concentrate free of chlorophyll.   

After the first wash has automatically been transferred to the Purification module, the Extraction module will automatically fill for the next wash. While this is taking place, the Purification module will begin to heat the cold concentrate.  

Typically, you will only need to complete two washes. This depends on the potency of the plant material. Most of the oil will be obtained during the first two washes. Lower quality plant material will not yield as much oil in two washes as a higher-quality plant. Each wash cycle will increase the quantity of oil extracted with diminishing returns. 
We recommend performing two to three washes for the best yields however, the system has the capability to customize the quantity of ethanol used for a wash, the length of time for the wash, as well as the number of washes for complete flexibility to meet our customers SOP.  

When the final wash has been performed and transferred to the Purification module, the Extraction module will send a signal to the Purification module to start the process. The system will then heat the concentrate to the designated setpoint and begin to purify the concentrate removing herbicides, pesticides, fungicides, as well as chlorophyll through a series of filters. The operator can then reload the Extraction module to wash additional biomass. 

When the purification process has completed, the purified concentrate will automatically transfer to the Distillation module where the ethanol will be removed from the cannabis oil. The cannabis oil will collect in the processing tank while the ethanol will be recaptured and ultimately sent back to the extraction module automatically so that the ethanol can be used again. The Distillation module can be set to leave a tincture or a decarbed fully purged crude oil. 

Benefits of an EPD System and Performance Tips 

Some competitive systems limit the number of times you can run the washes to complete the process. The EPD system’s programming allows customers to set up multiple wash times and control the length of time for each wash. You can set the first wash for 10 minutes, and the second or third wash for five minutes and one minute to vary the amount of wash time needed.


For optimal performance it is best to dedicate 10 to 15 minutes total of labor time to complete the process. This includes the time required to replace the filters, load the biomass, and set the processing parameters.  

Once a user loads the system with their plant material and defines their wash parameters, they can start the system and the process becomes fully automated from this point. The only time you need to come back is to replace the plant material and you may need to top off the system with ethanol. 

Usually, if customers fill up their systems with ethanol at the beginning of the day, they won’t have to recharge it for another day or two. This depends on how long or often the system is running. If you run the system 24 hours a day you might have to top it off more frequently.  

Using a fully automated system is much easier for the user and will extract the oil a lot quicker. It also cuts down on labor significantly. 

System Comparisons and Efficiency 

Now let’s compare the EPD system to using a centrifuge. If a lab chooses to use a centrifuge for the extraction it will get the plant material dryer, but it also brings out some of the less than desirable components of the plant material. Using a centrifuge adds an extra step that is not needed with an EPD system.  

Typically, companies need to take the concentrate from the centrifuge, and then use yet another piece of equipment to get rid of the ethanol from that mixture. An EPD system does the extraction, then transfers it over and recovers the ethanol automatically. We have done a deep dive on the EPD system but it’s important to know the difference among the various extraction systems.  

CBG Biotech has a line of CannaTrue™ Solvent Removal Series (SRS) Systems. They are designed to remove ethanol from concentrate. In most cases, these systems are used to replace rotary evaporators. The SRS product line is made from stainless steel whereas a rotary evaporator is made from glass. The Extraction, Purification and Distillation (EPD) System is designed to go from plant material to full spectrum and fully winterized.  

Those that have been in the Cannabis business may be familiar with Rick Simpson Oil (RSO) extraction. RSO is a marijuana extract made utilizing a solvent to extract cannabinoids. Grain alcohol is the most typical liquid used in the production of RSO. Alcohol is added to a flower (bud) substance in a sizable container. 

The SRS Systems promote stronger recovery of ethanol during the solvent removal and recycling processes. These systems recover solvents with 90-97% of their original purity at a recovery rate of 3-6+ gallons per hour. They are designed to enable bulk production and recovery in any volume, providing consistent product quality from batch to batch. 

To start this process, the operator will process their extraction in a centrifuge. This washing process takes out the oil from the plant material. Next, drain the centrifuge into the SRS system or container. Once the SRS has been filled, turn it on. Now the SRS system will heat up the mixture. You will be distilling the ethanol that you just loaded into the processing tank.  

Once the ethanol is gone, you will be left with full spectrum crude oil. It is very similar to the EPD and it will yield a very similar oil. However, unless the concentrate from the centrifuge was filtered, this cannabis oil will not be purified. 

Process Yields 

All these methods are used by many companies, but they do not all produce the highest quality yields. Our customers that use the EPD system have found they can process and extract oil much quicker if they do a terpene extraction of the plant material in the CO2 system.  

During this process a customer would start by putting the biomass into the CO2 system. Process the biomass in the CO2 system to perform a terpene extraction only. Remove the biomass from the CO2 system and then load it into the EPD to extract the oil.  

We have found that you can get through the plant material much quicker. This is because when you run just the CO2 system, it will take between eight and 12 hours to process. You will be left with a mixture that needs to be winterized. That consists of mixing it with ethanol and freezing it for up to 48 hours. 

After this process is completed, you will filter out the fats, wax lipids and gooey-like substance out of out of that mixture. Start by freezing the mixture. Once it hardens you can easily filter it out. Take that mixture and put it into a roto vat to remove the ethanol. 

If you want to get more biomass through the CO2 system do a quick terpene extraction. Put it in our system and extract the oil out (skip the winterization phase). Next is the decarboxylation process. 

Decarboxylation happens in the distillation module. Start removing the ethanol from the cannabis oil. Once the oil has been fully purged of the ethanol, the distillation module will go through a decarbonation phase that converts the THC inside the boiler distillation.  

The settings in the distillation module can be modified so that the oil can be left with a different consistency containing more or less ethanol. The system can leave a tincture in the processing tank or we can bring it down to a fully purged oil skipping the vacuum purge oven step. 

At this stage the cannabis oil will be an amber color and it may have a bitter taste. The oil can be taken directly from the system and put into a short path or a wiped film system. This all depends on what they're going to be doing with the oil.  

You can take the oil out of the system and create edibles, topicals, or tinctures. A customer may want to clean the oil if they want to create a higher purity oil or put the oil into vape cartridges.  

To remove and clean the oil you need to run it through a short path system. This is used to fraction out the different components like CBD and THC. After the process has been completed, the user is left with a nice higher purity gold colored oil. The remaining components in the boiling flask are discarded.  

The extraction process is much easier when you use a fully automated system. Learning how to use it is essential, but to continue getting those high-quality results you need to maintain the system. 

Maintaining Your Cannabis Oil Extraction System for Long-Term Use 

Preventative maintenance is important to keep your system running efficiently and effectively. CBG Biotech offers a Preventative Maintenance Plan to customers that can extend the life of the equipment and ensures you are performing regular maintenance.  

One of the great things about purchasing the plan is that a certified technician will come to your facility and will properly service the system. This includes checking out the components, changing out the heating fluid, cleaning the distillation column and software updates. 


Brad Kovach is an IT manager and PLC Software Engineer at CBG Biotech. He is a subject matter expert in extraction, purification and distillation processes and has worked at CBG for more than 25 years.

Learn More 

At CBG Biotech, we rely on a set of customer-first core values that promote ethical and honest behavior, personal accountability, and teamwork to deliver the solutions that set customers up for success. If you have a question or would like more info, please call 800-941-9484 (and press option 3 for support) or get in touch with us online today! 

Check out these other helpful resources: 

Topics: cannatrue, Cannabis extraction, crude oil, quality yield

Brad Kovach

Written by Brad Kovach

sign up newsletter

previously featured-1