Extraction Consulting for Cannabis and Industrial Hemp CBD
Most cultivation facilities include extraction as a central component of their production operations. This is perfectly sensible given the fact that the lower parts of your flowering plants contain plenty of valuable cannabinoids and terpenes but aren't worth the time to trim as sellable flower. Further, vape cartridges and other types of cannabis concentrates are gaining more and more market share all the time. Many consumers new to the cannabis culture gravitate towards non-smoke consumption methods such as edibles, vapes and tinctures. The market for extracted cannabis products represents more than 65% of all sales in some states. Let us help you sort out the different extraction methods that suit your production and marketing goals. We can design your extraction space, guide you through equipment choices, and learn how to operate your system.
Meet Chase Huff, our Extraction and Tissue Culture Expert.
How do you know which types of extraction machine and methods to use? Read on...
Meet Chase Huff, our Extraction and Tissue Culture Expert.
How do you know which types of extraction machine and methods to use? Read on...
Comparing cannabis extraction methods
Extraction is the process of removing key ingredients from cannabis plant biomass, and there are several methods of extraction to choose from in order to accomplish this goal. Different extraction methods will produce different product types, so it is important to have a clear understanding of your end goals when deciding what method of extraction to use. Each extraction method is also unique when it comes to investment cost, operating cost, post-extraction processing requirements, safety, and the derivative products that can be manufactured from the extracted material. Here we will discuss how these extraction processes differ and why you might choose to select one method over another, or combine methods, into your extraction and manufacturing operations.
Hydrocarbon Extraction
Hydrocarbon extraction uses Butane and/or Propane as the solvent. These solvents have greater selectivity for the specific compounds that we want to extract from the cannabis plant: cannabinoids and terpenes. Selectivity equates to efficiency, and hydrocarbon extractions can thus be performed rather quickly with smaller and larger batch sizes, leading to a suitable throughput for most operations. Part of this efficiency is due to the fact that hydrocarbon extraction tends to not extract as many of the waxes and fats that other methods may co-extract along with the desired molecules. In terms of post-extraction processing, hydrocarbon extraction does require some extensive solvent recovery in order to remove the residues of butane and/or propane from the cannabis concentrates. This recovery process adds to the overall processing time and reduces some of the overall efficiency of this method.
Closed-loop hydrocarbon extraction systems are cheaper to buy than CO2 or ethanol systems, but they do require a C1D1 extraction room. C1D1 is a building code designation that is necessary in order to meet fire code safety requirements while using these explosive and highly flammable solvents. It's pretty costly to set up, so for that reason, turnkey extraction booths that are pre-engineered for safety are often chosen as a substitute. Hydrocarbon extraction is the least safe cannabis and hemp extraction method and has been banned from use in certain regions due to its risk. That being said, hydrocarbon extraction is one of the best for producing dabb-able concentrates such as wax, shatter, badder, diamonds, live resin dabs and vape carts.
CO2 Extraction
CO2 extraction is performed by using temperature and pressure to control the nature of the CO2 molecules, to make Co2 behave like a solvent. Through the control of temperature and pressure, CO2 can be brought to its supercritical fluid state, or its subcritical state, in order to produce extracts from cannabinoids. Both states have an individual purpose in cannabis extraction.
One of the greatest benefits of CO2 extraction is its tune-ability and selectivity. With the proper protocols for controlling temperature and pressure, the extractor is able to target specific subsets of molecules in the biomass. For example, if you wanted a waxier extract for topical manufacturing or a terpene rich fraction, you can change your temperature and pressure parameters to get your intended outcome. No other method of extraction offers this kind of selectivity and tune-ability. The downsides to CO2 extraction are the expensive capital investment costs and the lower throughput. Also, Co2 oil has an inherently sour taste that some consumers like to avoid in vape products.
C02 extraction systems require expert engineering and design sophistication, which are not cheap, and each extraction batch takes significantly more time to run than other extraction methods. On the other hand, CO2 is a non-toxic solvent that evaporates out of the cannabis concentrate and does not require post-extraction processing unless you want to remove co-extracted fats and waxes. This method is generally regarded as the best method for producing medicinal-grade products due its lack of toxicity and residual solvents.
Ethanol Extraction
Ethanol is much more aggressive and less selective as a solvent. This means that ethanol extracts more total compounds from the plant, which can be good for those who want to produce a more broad-spectrum extract. Ethanol extraction can be performed at very cold temperatures in order to reduce the strength of the solvent, which reduces the amount of undesired compounds that are co-extracted with the desired compounds. This method also has the highest throughput of any of the extraction methods and is great for large scale extraction. Due to the broad-spectrum nature of ethanol as a solvent, more post-extraction processing is necessary to produce higher-grade concentrates.
Compared to hydrocarbon or CO2 extracts, the cannabinoid potency of ethanol extracts is generally lower prior to post-extraction processing. These extracts are typically “cleaned up” using methods such as winterization, distillation and chromatography. The crude oil can also be sold as what is commonly referred to as “Rick Simpson Oil” and has been the popular choice for cancer patients and those seeking the full spectrum of medicinal properties from the plant. Although not nearly as explosive and flammable as butane and propane, ethanol is flammable and does require an extraction space meeting C1D2 requirements (less stringent than C1D1). Depending on the scale of ethanol extraction, the capital costs can be similar to CO2 but the throughput is much higher and thus ROI is realized sooner.
Solventless Extraction
In recent years, solventless methods of cannabis extraction have really taken off in the industry as a means of producing a high quality product that connoisseurs prefer. Solventless extraction means just that--the desired compounds are removed from the plant material without using a chemical solvent. These extracts can be made in various ways but here I will describe the 2 common ways that we see these types of cannabis extracts produced on a commercial scale.
The first method is a mechanical extraction process using ice water. The “ice water hash” process uses ice water to freeze the trichomes on the flower surfaces, and then mechanical agitation is used to knock the trichomes off of the plant material. The trichomes are then filtered out of the water using various sizes of micron screens to collect different quality levels of resin glands. This “ice water hash” or “bubble hash” can be dried and sold as-is, and many people enjoy dabbing this product or adding it on top of smoked flower.
The second common method of solventless extraction is referred to as “rosin pressing” and utilizes heat and pressure to essentially melt the desired compounds from the flower material. Rosin pressing can also be performed on water hash which is common for the production of the most premium rosin products on the market. With post-processing performed on the rosin, it can be made into different consistencies and can even be used to form crystalline THCA, or "diamonds" as many people refer to them, just like live resin can do after it is produced from hydrocarbon extraction. This method requires a much lower capital cost, is extremely safe, has a decent throughput, and produces very high quality products that have no residual solvent and are therefore great for medical patients and recreational consumers alike. These products also command a higher price point. The main downside to solventless cannabis extraction is that it has a much lower yield than other forms of extraction, and not all cultivars yield well with this method. It takes extra experimentation to dial it in.
If using a solventless extraction method, we recommend combining it with a solvent-based extraction method so that processed plant material can be further processed to remove all valuable compounds, resulting in zero wasted material.
We'd love to help you design, plan and implement your cannabis or hemp extraction facility.