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A Visit to a Hemp Processing Plant

Thu ,20/07/2023
Hemp’s uses.

Last Spring, a group from the Sierra Club visited Midwest Hemp Technology. The Sierra Club is interested in agricultural hemp because if it’s benefits to the environment. One acre of hemp sequesters 4 to 6 tonnes of CO2, similar to the amount sequestered by a young forest, but it only takes five months to grow. Hemp helps pollinators as its flowering cycle usually occurs between July and September, coinciding with a lack of pollen production from other crops. Hemp produces large amounts of pollen and provides shelter for birds and hemp seeds for food for animals. Use of hemp products can save forests, reduce plastic waste, improve the soil, and greatly cut our greenhouse gas emissions. And it is profitable, as hemp normally produces 2 to 3 times as much income per acre as corn or soybeans.

Hemp has been grown for over 4000 years, and one website claims over 50,000 uses for hemp products. Its usefulness has been its downfall in the United States. Hemp and marijuana are essentially the same plant, but hemp has less than 0.3% THC by dry weight while marijuana has considerably more and is intoxicating. Competing industries, such as the paper, plastic, and cotton industries, have used hemp’s similarity to marijuana to essentially ban hemp in the United States for about the last century. Hemp, quite wrongly*, has been classified as a schedule one drug and only recently has it been legal to grow it in the United States, with the passage of the Hemp Farming Act in 2018. Though it can now be grown legally in Kansas, it is heavily regulated by the state, which has been a barrier to using it more widely.

The tour started in the office with a display of many of the products made from hemp. The picture on the left shows how hemp can be made into webbing, fiberboard, a finished wood substitute, cloth, and even hats.

The hemp utensils were my favorite as they show hemp can replace many single use plastics. Hemp can be made into such items as carry out boxes, plastic forks, straws, and plastic bags. Hemp plastics are compostable and biodegradable and break down rather quickly in the environment. Use of hemp would greatly cut down on plastic litter and plastics in the ocean. Birds and animals that ingest plastic often die from it. Microplastic particles from production, the breakdown of plastic products, and even from synthetic clothing, have become ubiquitous. A recent study found that eight out of 10 people have plasticizers and microplastics particles in their blood. That is certainly is not a good thing, as they have been associated with hormonal disruption and and a variety of other diseases.


Hemp is a useful building material as it can be made into wood, particleboard, insulation, and plastic-like materials. Given its light weight and durability, hemp is being used as a substitute for plastics in sectors such as car manufacturing, railway, aviation, and aerospace applications. When combined with lime and water, it makes hempcrete, which can be substituted for concrete in most applications. This is important as about 9% of the United States’ carbon emissions are made in the production of concrete. Hempcrete will last for centuries, is a good insulator, and is mold, mildew, pest, and fire resistant. Hempcrete, even considering the energy used to produce and harvest the hemp, actually sequesters carbon. The hempcrete block on the right looks a little rough, but here are some examples and a movie of buildings made with hempcrete. There is a shortage of workers who know how to build with hempcrete, and there is now a program to help veterans learn it as a trade

A Hemp Field in Bloom

Aside from regulations, hemp is one of the easiest plants to grow and one of the fastest growing biomass products in existence. It uses less water than cotton, and requires minimal pesticides to thrive. Hemp helps to break the cycle of diseases when used in crop rotation. In addition, weeds are not able to grow due to the fast growth and shading capacity of hemp plants. The dense leaves of hemp are a natural soil cover, reduce water loss, and protect against soil erosion. Hemp covers the ground just three weeks after germination. Hemp is susceptible to few pests and the use of insecticides, herbicides, and fungicides can be avoided in most cases.

One problem with hemp production is the lack of custom equipment to harvest and process the hemp. Farmers and hemp processors have been quite creative in modifying existing equipment or building their own equipment to process hemp. When harvested, hemp is usually cut and baled into large bales similar to round hay bales.

Trommel, separates hemp fiber from seeds and hurd.

At processing, the bales are broken apart and put through the trommel which separates out the bast from the seeds and hurd. Bast is the long fibers just inside the stalk, and hurd is the pith, the woody inner core of the plant. The stalk can be converted into fuel and paper products like cardboard. The long fiber strands extracted from the hemp stem have long been used to make textiles, rope, and webbing. Hemp makes extremely durable clothes and accessories, such as shirts, skirts, bags, shoes, and belts. Hemp has anti-microbial properties and the fabric is stronger and more durable than cotton and, unlike cotton, hemp clothes will not lose their shape with repeated washing.

Air classifiers, which separate different sizes of hurd from the grain.

From the trommel, the hurds and grain are directed to the air classifier. Depending on the settings, the air classifier separates different sizes of hurd from the grain. The hurds may be used for horticulture mulch and for other agricultural uses. They absorbs moisture which makes them very useful for animal bedding and litter. The hurds can also be used to make hemp plastic and building materials. When the hurds are mixed with lime and water, they make hempcrete. The hurds may also be mixed with a polymer to create a fiber-reinforced biocomposite, and if the hurds are reduced to micron sized particles first, the product is much like plastic. If the polymer used is petroleum-based, the hemp plastics are not compostable. However, sustainable bioplastics may be made if plant-based polymers from corn or kenaf are used.

This is the grain cleaner.

The grain cleaner is the last step of the process. The hemp seeds are then used for food flour, hemp milk, cooking oil, and beer—as well as dietary supplements. Some companies sell the edible seeds of the hemp plant. These seeds have a mild, nutty flavor and make milk, oil, cheese, and protein powder. The seeds are a rich source of polyunsaturated omega-3 and omega-6 fatty acids, essentials for human health. Unhulled seeds are sold for bird and animal food. Other uses of hempseed oil are to make body-care products, biofuels, paints, and varnishes. According to the FDA, hemp seeds do not naturally contain THC or CBD oil.

Hemp in Kansas : Kansas used to grow a lot of hemp and, one year during the Civil War, Kansas grew more bushels of hemp per acre than any other state. However, economic competition with cotton, timber, and synthetic plastics – all backed by wealthy corporations – led to anti-hemp propaganda that caused a moral panic. It portrayed hemp and marijuana as being the same and that they would lower the moral values of American culture. This led to the Marihuana Tax Act of 1937 which essentially banned Hemp production in the United States. The ban was essentially ignored when hemp was needed for the war effort, and the government even subsidized the production of hemp. After the war, the ban went back into effect and, in 1970, President Nixon signed the Controlled Substances Act which officially outlawed hemp and marijuana for any use (medical included) by declaring they were schedule one drugs. The Farm Bill of 2018 authorized the commercial production and processing of hemp, but it remains a Federal schedule one drug to this day.

Hemp can now be legally grown in Kansas, according to state law, but the laws are very restrictive. Applicants must submit a fingerprint-based state and national criminal history background check. The application fee is $100 and is due with the application no later than March 15 each year.  The background check fee of $47 per person, including the farmer and all workers, is due no later than March 15th each year.  A license fee of $1,200 is needed to cultivate or produce industrial hemp are due no later than March 15th each year. All forms and fees must be paid and filed by that date or they will not be approved. Industrial hemp producer must use authorized seed, guaranteed to produce industrial hemp with not more than 0.3% THC, so grower may not save their seeds for the next crop. Both federal and state rules surrounding the crop are in constant flux, so finding investors to spur innovation and development will remain challenging. There are no insecticides, no fungicides, no herbicides labeled for this and there’s no crop insurance and no safety net for it. And to complicate things, even though a state can legalize growing hemp, the federal government still views it as a dangerous drug, the same as heroin or cocaine. Among other consequences, that makes it difficult for potential growers and processors to secure loans from traditional banking.

Kansas Hemp growing licenses dropped  from 218 in 2020 to only 81 in 2022. Of the 4,000 acres planted, only 761 were harvested for production. and an eighth of that had to be burned by the state because it contained too much THC. Hemp growing licenses dropped  from 218 in 2020, to only 81 this year. Of the almost 4,000 acres planted last year, only 761 were harvested for production. and an eighth of that had to be burned by the state because it contained too much THC. Hopefully both national and state laws will improve so that hemp can profitably be grown. As one Kansan wrote, “My son is taking over his in-laws’ farm, and it is very important to keep our young kids on the farm. I am very proud of him for taking on this challenge. Farmers need all the help they can get, and hemp is a very lucrative crop to grow. This is very important for Kansas and our young farmers. Thanks for your help.”  

*Note: 2010 study in the journal Lancet graded common drugs on sixteen criteria relating to how harmful the drugs were to users and to society overall. On both measures – marijuana scored significantly lower than alcohol and ten other drugs. THC is not physically addictive and scored below tobacco in terms of harm to the users. Marijuana should probably not be listed as a schedule one drug, and certainly hemp should never have been.

(C) 07/23/2023 – J.C. Moore