Hemp is a cellulose-rich plant, and a core crop in sustainable agriculture. Its strength and durability surpass other fibers, and as such, it requires multi-stage processing. Updating how hemp fiber is processed and extracted has been instrumental in maintaining its viability.
Hemp is made up of inner and outer layers of plant cells – specifically, chlorophyll cells and bast fiber cells. The total fiber content of a hemp plant can be between 25% – 35% of its stem dry matter, and its useful CBD content can range between 7% – 15% per pound of plant matter. During the harvesting process, great care must be taken to protect both the CBD content, and its lignin, or the valuable tissue of the plant.
Hemp is harvested for its seeds and its stalks. Hemp seed can be either hulled, where the meat of the seed is taken and used for food, and the shell can then be ground to flour, or it can be pressed, where oil is made and then used and processed into food, fuel, paint, nutritional supplements, and personal care products. Hemp seeds can also be crushed into a cake that can also be used as food, or further processed into products such as beer or animal feed.
When hemp stalks are harvested, a three-step decertification process separates the fiber from the hurd, which is the non-fibrous, woody, inner layer of the stem. First, the primary fiber is hackled, which involves separating the hemp and drawing it through a steel comb, or hackle, which further separates its fibers. This process leaves the primary fiber smooth and ready to be used for fabric, insulation, carpeting, and paneling. Once separated, the secondary fiber can be used for cordage, pulp, and as a recycling additive. The coarse part of the secondary fiber, or tow fiber, left over from this process can be scutched, or further beaten and woven, into cordage bagging or fiber board. Finally, the hurd of the hemp stalk can also be scutched into fiber board compost, paper filler, absorbent, and bedding, and its chemical feedstock can be used for plastics, paints, and sealants.