The use of plants with medicinal effects dates back hundreds of years and continues to be valid because of the benefits that plants have demonstrated. One of the most emblematic cases is the use of Cannabis or, as it is commonly known, Marijuana. However, until recently there were strong restrictions on its use, even for medicinal purposes.
The recently enactment of strict laws and regulations for its control mainly in US and Canada projects cannabis as one of the fastest growing industries in the coming years. Its legalization has been accompanied by countless studies that have demonstrated the therapeutic effectiveness and safety recreational use of cannabinoids.
Today, the industry is exploring many other applications as fertilizer, or as food or cosmetic supplements. In any of these applications it is required that the cannabis presents purity levels appropriate to the use it is intended to.
Marijuana dry extraction method
The extraction of marijuana is carried out by two main methods: through extraction with industrial solvents or through the so-called dry extraction. Dry extraction is a more natural and pure way to obtain the trichomes of the female buds and flowers where the cannabinoids are concentrated.
Dry extraction methods
These are purely mechanical extractions carried out by pressing, rubbing or sieving.
A traditional form of presentation of marijuana is bricks. This was a very common method used before the legalization of cannabis consumption, as it was a way of compacting it to facilitate its hidden transportation. It consists simply in the pressing by hydraulic means of all the material of the plant, so its purity is usually very low.
Rubbing is the most artisanal way to obtain cannabinoids. The buds and leaves are rubbed until the hands are impregnated with plant’s resins, which are highly sticky. These resins are contained in glandular trichomes densely covering the female buds and flowers. Subsequently, with circular movements of the fingers, the residues that remain on the hands accumulate to form small masses which are then joined to get longer ones.
Finally, another traditional technique is sieving. In this extraction method, the plant material is sieved to obtain the glandular trichomes. In home extractions, marijuana flowers and buds are placed in homemade strainers and shaken with the use of hands only. In the case of industrial extraction, more sophisticated screening equipment is used.
Screening equipment for Cannabis
The chemically active compounds of marijuana are found, as we saw above, in the glandular heads of specialized trichomes located in the female buds and flowers. Therefore, during dry extraction, the plant material must pass through a series of sieves that sift out the smaller and smaller particles until only the portion corresponding to the trichomes is obtained.
Industrial processes in which large quantities of raw material are processed to obtain cannabinoids have much more modern screening equipment. This equipment incorporates large drums in which the centrifugal force allows the separation of the different plant components, which are then sieved through columns of sieves.
With the use of different sieving diameters, this equipment allows the elimination of any contaminant from the final product, obtaining almost pure glandular trichomes extract. The rest of the material can again be subjected to other extraction processes to obtain as much cannabinoids as possible.
As the therapeutic and recreational use of marijuana has been decriminalized, the industry for its production and commercialization has been growing rapidly. Its current influence is so great that it is quoted on the stock market as a raw material, and can push the numbers up or down depending on whether its use is decriminalized or not.
Discussions about its therapeutic or recreational use are advancing at different speeds, but there is no doubt that the marijuana industry will give much to talk about in the coming years.