The Commercial and Industrial Hemp Symposium
I am a paper maker, forming sheets at the vat with a mould and deckle in the traditional manner. For about five years now, I have been making paper from hemp, using anonymous donations from hemp farmers in Southern Humboldt and Northern Mendocino counties, California. I have applied for a permit with the DEA to cultivate fiber hemp, and both the DEA and the State of California have agreed that I am in full compliance with all of their requirements, and I expect to finally get my seeds in the ground this season.
It is widely understood that hemp is one of the finest materials available for papermaking. For over 2000 years, until about the last 150 years, hemp has been one of the predominant materials used for making paper.
But times have changed. Instead of paper being fine material for books, bank notes, and title deeds, it is now a multi-billion dollar industry flooding our world with tons of low quality junk mail and office paper. Most of the hemp which is currently being used in paper making is the pure bast fiber which has been decorticated at great labor and expense. This bast fiber is what I want to use in my own work (making hand made paper), but I am interested in the commercial potential of using the whole stalk of hemp, not just the 30% which is the bast fiber portion. Even though the core material is composed of short fibers, it is still high in cellulose and contains less lignin than wood.
One of the advantages of using the whole stalks of hemp is that the farmer can cultivate a seed crop first, and then sell all remaining biomass to the pulp mill. This dual crop strategy, with both crops being high yielding and high value, can make hemp a very profitable crop for the farmer.
You may have heard that for optimum fiber quality you need to harvest before the seed matures, but the reduction in fiber quality is really very minor, and is greatly overshadowed by the economic advantage of having two crops to sell.
In addition to hemp, there are a great many other materials that could be included in the production of a low cost alternative fiber paper that effectively recycles all available sources of cellulose. This includes kenaf, which I also use. It is excellent stuff, not quite as good as hemp, that grows in warm climates.
Also, there are many tons of agricultural waste material that are annually available, and should not be overlooked, including wheat straw, rice straw, sugar cane bagasse, etc. In addition, recycled paper could also be included, as well as rags of cotton, linen, hemp, and other natural fibers. I know a manufacturer of wedding gowns that has to pay to discard their new, clean, white, 100% cotton cutting scraps as landfill.
I also make paper from many of the weeds that grow wild in the fields around my hills in Northern California, and I have learned that you can make paper from just about anything.
When you put all of these materials together, you can produce a very low cost alternative fiber paper that can be marketed against the wood-pulp paper industry very effectively.
The challenge of the Alternative Fiber Paper Mill will be to evolve new methods of producing pulp that overcome the limitations of present day wood pulping facilities. One of the most promising new technologies has been proposed by Dr. Krotov of the Pulp and Paper Research Institute of Kiev, Ukraine.
It is a single unit, closed system "drip percolation pulping process with aqueous organic ammonia and sulphur dioxide solutions," in which the chemicals used are entirely recovered for re-circulation into the process, resulting in a progressively cleaned material. The remaining dissolved solids separated from the cellulose may be used as a high nitrogen fertilizer, or further separated into marketable products.
Other advantages of the Krotov design are: lower capital and operating costs, reduced water use, 30 - 40% lower consumption of raw materials, energy and labor costs decreased 3 - 5 times, higher yield of pulp, better hydrogen bonding due to a higher percentage of hemi-cellulose, and better delignification without the use of chlorine bleaching.
Our financial projections suggest that a test unit could be built for less than $2,000,000 with a capacity of 10 tons of pulp per day, and a profit to the operators of over $1,000,000 per year.
There are other designs also proposed, such as the Tigney process designed here in Canada, based on a steam explosion process that separates the components, providing a number of marketable products in addition to the cellulose fiber.
The best approach, which I am trying to realize, is to fund an Alternative Fiber Paper Mill that will actively explore all options in order to maximize the effectiveness of utilizing all available resources to produce paper as inexpensively as possible, with the least impact upon the earth — and so that the Trees which are left to us may be allowed to go on living.
- John Stahl
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