What is BHO
BHO is an abbreviation for Butane Hash Oil. The name comes from the extraction method used to produce the cannabis extract: soaking the cannabis in butane to separate the cannabinoids from the raw material. Butane extraction is one of the most common extraction methods and has been around for the better part of the last 20 years.
Prior to Butane extraction, most extractors we’re making bubble hash – a concentrate made using ice water and filters. We’ll save the details of Bubble hash for another day. This post is all about the butane baby!
How is BHO Extracted
Plant material (trim, flower or fresh frozen) is loaded into a tube or extraction column. First, let’s identify the differences in material.
Trim refers to trimmings of a cannabis plant cut off in the trimming phase after harvest. This includes sugar leaves, small buds, trichomes that were knocked off in the harvest process, and kief.
Flower refers to smokable buds. While the flower is typically produced to be smoked, sometimes it is used in the extraction process to make extracts.
Fresh Frozen is the newest input material that extractors use to extract. This technique involves flash freezing the plant as soon as it is cut down in the cultivation phase. This is typically performed with dry ice and then sealed and stored in freezers until it is extracted. This process preserves the most terpenes and is the input for the ever-popular product live resin.
Once the material is loaded into an extraction tube or column, the material is soaked in butane to separate the cannabis oil from the plant material. There are several ways this process can be performed.
Open Blasting – Open blasting is the original method used for butane extraction. This method is outdated and is rarely used today because it is very dangerous and you waste all of the solvent. In open blasting, the material is
loaded into a glass tube. One end has a port for butane canisters, and the other is open to allow the hash oil and butane to come out. You continue to push butane over the material and collect it in a Pyrex dish until it runs clear.
This method poses obvious dangers because the highly flammable butane is escaping into the atmosphere. This poses a big risk of fires or explosions. Any ignition source can be dangerous and even deadly.
Closed Loop – Closed loop extraction was invented to solve 2 problems posed by open blasting – dangers of flammable gasses escaping, and to be able to reuse the solvent. In a closed loop extractor, butane is filled into a pressurized tank that is connected to the extraction tube or in this case the extraction column. Like open blasting, the butane is pushed over the material column to separate the oil from the plant material aka biomass. However, after the solvent is pushed through, there is another solvent storage tank connected to the extraction column where the butane is recollected. While this is a much safer process, hydrocarbon extraction (butane or propane) can still be very dangerous.
It’s very important to check the butane extractor before each use to make sure there are no leaks. Leaks can come from blown gaskets, loose connections from hoses, etc. It is also important to preform the extraction process in a safe environment. Butane extraction should always be performed in a C1D1 (Class 1 Division 1) explosion proof room. C1D1 rooms contain the volatile extraction process and continually remove any butane or propane vapors from the room, keeping the environment safe for the extractor.
Finishing the Product
Once the BHO has been extracted, it must be carefully finished to ensure the product is safe. The cannabis hash oil still has high levels of butane, and the solvent purging process must be carefully completed to ensure there is little to no residual solvent in the finished product. Residual solvents inhaled at high temperatures can introduce carcinogens into your body, causing severe health concerns.
The way BHO is purged from the extract is typically done in vacuum ovens. Vacuum ovens apply heat to the product while pulling vacuum, allowing the butane to evaporate out of the hash and be pulled out of the product.
There are different techniques for finishing BHO to produce different consistencies of hash oil. Different BHO extracts include wax, budder, shatter, sauce, live resin, crumble, and coveted diamonds. Each product has a different consistency, and cannabis connoisseurs enjoy consuming it in different ways, most commonly dabbing.
One of the most popular and skillfully made extracts are THC Diamonds. This process involves the recrystallizing of THC molecules, creating beautiful (and highly potent) diamond-looking formations.
If you’re interested in starting a butane extraction lab, H&H can help you every step of the way. If you’re in need of equipment, engineering, or process consulting to get your lab up and running – reach out to us today!