What does your extraction method mean for your facility?
You can’t just choose an extraction method for the end product, you have to think about how it will affect your facility now, next year, and 5 years from now.
By Bre Whitehair - August 10, 2020
Probably no other topic gets people as riled up in the Cannabis and Hemp world as which extraction method is “Best”. As you can probably imagine, best can be a hard thing to pinpoint and depending on what the goals are, the answer can change. I want to dive into some points that I think get glossed over when comparing methods. You can’t just choose an extraction method for the end product, you have to think about how it will affect your facility now, next year, and 5 years from now.
First things first, you need to talk with your fire dept and AHJ (authority having jurisdiction) from the moment you start planning. Getting them involved and signing off on your plans as soon as possible will save you untold headaches. No matter what solvent you choose, you will need flammable solvent on site. It’s imperative to how much solvent you can legally have onsite. Flammable solvents mean C1D1 enclosures. All of these things affect the cost of your build out and when you start turning a profit. Another thing to consider when planning is to keep in mind the future possibility of expanding and adding production capacity when your business grows.
Let’s start with the obvious, hydrocarbons are going to be the toughest method to scale up. Given how flammable they are, there are more intense regulations and higher scrutiny on these facilities. Though the equipment may not be as expensive upfront, your facility build-out will be. Delays from the fire department and other folks means your first run, and first paycheck, are likely to be later than you planned. Overall hydrocarbons are best suited for small scale boutique processing and for knowledgeable customers willing to pay a premium.
Now let’s get into the meat of it, CO2 vs Ethanol. This is where I see the most misinformation. Depending on what you read you may be thinking “I’ll just skip all this solvent and flammability stuff and go with CO2”. Again, CO2 has a place but don’t forget you will still need to dissolve your crude in ethanol, winterize it and recover your solvent. Let me say that again YOU WILL STILL NEED EtOH ONSITE FOR CO2 EXTRACTION. In addition to that, your winterization will need to be serious with -40C vessels. So, in the end you have the same amount of risk as going with ethanol but more steps and more expensive equipment up front.
Starting a CO2 facility is going to also be an investment upfront. It’s the most expensive equipment to purchase up front. Generally, it takes more skilled operators to run and you’ll still need flammable solvent storage and C1D1 space. CO2 is also a slow method of extraction meaning you have fewer possible runs per day. Lastly, you’ll need to prepare for everything to be rated for high pressure, compared to EtOH and hydrocarbon which both run under vacuum. This all means is that it’s going to be hard for you to be agile in how much you are processing and harder to scale up quickly. CO2 also requires more steps to get to crude oil than a well designed EtOH process. All that being said, it is a great method for extracting terpenes with your Cannabinoid.
Lastly ethanol is going to be the easiest method to scale up and the least expensive method per gram of product produced. It’s not without it’s facility concerns though. You will need C1D1 facility. You’ll need storage for a flammable solvent and there will be a maximum amount of solvent you can have onsite. If planning to skip winterization, you will also need a freezer onsite for freezing your biomass prior to extraction. The EtOH extraction is processed under vacuum vs CO2 being processed under high pressure; this makes piping and vessel requirements cheaper and easier. EtOH can be processed in either a batch style system or a continuous extraction process. Batch style units have the advantage of being less expensive upfront and very flexible in size of runs. Continuous extraction on the other hand is great for processing a lot of biomass very quickly and efficiently.
Obviously, there is a lot to consider when starting an extraction facility, but don’t be scared off after reading all this. Quality advice is worth its weight in gold and if I may be so bold, a great place to get the knowledge is Pinnacle Stainless.