Grass paper

The basis for the industrial production of paper are fiber materials that are usually obtained from wood (cellulose, semi-cellulose) or waste paper, as well as so-called fillers. In the manufacture of grass paper , grass is used as a biological filler with up to 30% volume for paper production.

history

Today, pulp , which is usually obtained from wood or waste paper, serves as the basis for the industrial production of paper . Especially in the 17th and 18th centuries, however, natural scientists and entrepreneurs such as Jacob Christian Schaeffer, Leorier de l'Isle, Justus Claproth, Louis Piette or Johann Gottfried Dingler were already concerned with the systematic research and testing of alternative raw materials for paper production, because the papermakers repeatedly cannot meet the demand due to a lack of raw material (" rag paper "). So Schaeffer u. a. with tree moss, hop tendrils, straw, leaves, nettles, cotton grass, thistles and much more. In 1784 Varenne published the book Loisiers de Bords de Loin, which contains samples of rag substitutes (grass, silk and the bark of the linden tree). The Academie de Sciences (Paris) declared in 1786 that the papers made with grass by Leorier de l'Isle were superior to the Schaeffer's papers, but this was probably due to the addition of rags to the grass paper of de L'Isle. The use of grass fibers in paper was not the focus of industrial paper production because of the availability of more suitable substitutes such as straw. However, there are anecdotal reports - especially in Asia - about the use of grass as a filler.

Recently, the subject of grass paper has been discussed again in industrial circles, in particular because of a raw material "Graspap" made from pelletized hay and sold by the company Creapaper, Hennef. The first industrially manufactured packaging products with grass pap, but also unpelletized hay fibers, have been on the market since 2015. These papers require a pulp content of at least 70 percent (made from fresh fiber or waste paper fiber). The reduced pulp content leads to a reduced ecological footprint on the one hand, but also to lower strength values ​​of grass paper on the other. A high-quality printability of the products also requires special coating processes.

Manufacture of the pulp

Since the grass pulp for modern grass paper production consists of hay, which is cleaned and cut, but is not subjected to pulp digestion, the energy consumption and the associated emissions are significantly lower than in comparison to pulp made from wood. This is due, among other things, to the high lignin content of the wood. Lignins are biopolymers that give wood its strength. Depending on the type of tree, between 55 and 60 percent of the wood consists of cement substances that are undesirable in paper production. For this reason, the lignin must be removed before the wood pulp is processed for paper production with high energy, water and chemicals.

Grass, on the other hand, contains little lignin, so that a relatively simple mechanical treatment is sufficient. The grass, which has been dried into hay, is ground into short fibers. The fiber lengths correspond roughly to those of conventional fibers in paper production. The fibers can be pressed into pellets for easier transport. The process reduces the use of water from an average of 6,000 liters per ton of pulp to two liters per ton of pulp. At the same time, energy consumption drops from around 2300 kilowatt hours per ton of pulp to less than 150 kilowatt hours per ton of hay. Chemical substances are not necessary for the preparation of the grass.

On the other hand, it must be taken into account that the constituents present in higher quantities in undigested natural fibers, such as hemicellulose and proteins in classic industrial paper manufacture, as well as the lignin mentioned above and also contained in the grass fiber, are considered to be disruptive substances, which in any case when such Natural fibers require a change in the usual paper manufacturing processes and recipes. In addition, cellulose consists predominantly of cellulose, which allows good formation of hydrogen bonds between the cellulose fibers, which in turn essentially determines the strength values ​​of the papers made with it. In the case of grass fibers, however, the cellulose content is below 30%.

Reduction of pulp imports

Around 80 percent of the wood and pulp required for conventional paper production is imported into Germany. The paper industry is increasingly relying on short-fiber sulphate pulp , which is obtained from fast-growing hardwoods. The pulp comes from eucalyptus , among other things , which is native to regions near the equator. In 2016, short-fiber pulp accounted for a little more than two-thirds of total pulp imports. The main pulp import countries are Brazil, Finland, Sweden, Portugal, Chile, Uruguay and Spain. The pulp used for paper production in Germany can travel up to 9,000 kilometers. The hay used for grass paper production is u. a. Extracted on so-called compensation areas from the direct vicinity of a paper mill. The extraction of raw materials should therefore not be in direct competition with the feed supply of farm animals.

CO ₂ emissions

Around four million trees are felled every year for German paper requirements alone. If only 25 percent of Germany's paper requirements were to be produced with rapidly renewable annual plants such as grass or straw instead of wood, a million trees would be preserved every year. Extrapolated to the world market, this would have a significantly positive impact on CO ₂ emissions and thus a measurable impact on the world climate. It should also be taken into account that the production of recycled paper requires the production of pulp and thus also the consumption of wood. In Germany, waste paper fibers are "finally" consumed in only 5 to 7 uses on a statistical average and may not be used in direct contact in food packaging.

Proven applications

In industrial production, grass paper can consist of up to 40 percent grass fibers, depending on the intended use. The combination can be made with both wood pulp and waste paper. Grass paper is already used for food packaging (e.g. for fruit, vegetables, eggs, etc.) or for repackaging cereals, confectionery, baked goods or cosmetics and drugstore items. Service packaging (folding boxes, labels, displays, brochures) is now also made from grass paper. Graphic papers and hygiene papers with a grass content are already available. The companies that already use grass paper include Coca-Cola, Otto Versand and grocery stores such as Rewe, Lidl and Aldi.

Development, patents, awards

The company Creapaper holds a patent for a process for processing grasses into pelletized substitute fibers. The process was developed with the support of the German Federal Environment Foundation and the Rheinische Friedrich-Wilhelms-Universität Bonn . Creapaper received several awards for its development, including the Start Green Award 2016, the KfW Entrepreneurship Award 2017, the Innovation Award for Climate and Environment (IKU) 2017 and the Red Herring Top 100 Award Europe 2019. Scheufelen was founded in 2017 Luxepack, New York received the "Best in Green Award" as well as the "Best Sustainable Packaging Innovation Award" from Packaging Europe, UK and an "Innovation Award" for grass paper packaging from Fruit Logistica, Berlin.

The company Kiss My World from Hamburg receives the Green Product Award in 2019 for its sustainable and unique paper and stationery made of grass paper

Web links

• Grass paper: These cardboard boxes are made of grass - Utopia.de
• Grass paper - an environmentally friendly alternative? - Printelligent.de

Individual evidence

1. ↑ Hans-Jürgen Wolf: History of paper - historical basics portraits technology . 1st edition. Historia, Ulm 2012, ISBN 978-3-00-039165-1 , pp. 674 .
2. ↑ Hans-Jürgen Wolf: History of the paper . S. 682 .
3. ↑ Hans-Jürgen Wolf: History of the paper . S. 681 .
4. ↑ StartGreen - Green Founders, Green Economy
5. ↑ KfW Entrepreneurship Award 2017: Successful founders honored in Berlin
6. ↑ Creapaper GmbH - IKU
7. ↑ 2019 Red Herring Top 100 Europe Winners - Red Herring
8. ↑ in green Awards. Retrieved September 27, 2019 . 
9. ↑ Scheufelen. Retrieved September 27, 2019 (UK English). 
10. ↑ Germany's Papierfabrik Scheufelen wins Innovation Award for its grass paper packaging at Fruit Logistica in Berlin | RISI Technology Channels. Retrieved September 28, 2019 . 
11. ↑ Kiss My World - grass paper. Retrieved March 13, 2020 .