PAPERmaking! Vol7 Nr3 2021

www.nature.com/scientificreports

’ƒ –‘ˆ•Š”‡††‹‰†‡‰”‡‡ ‘’ƒ’‡”ƒ‹‰’‘–‡–‹ƒŽ ‘ˆ”‡ › Ž‡†™ƒ•–‡ ‡–ƒ‹’‹‡™‹ œ ͷ ǡ†›–ƒƒÏƒ Š‘™•ƒ ͷǡ͸ * ǡƒ” ‹—„‘™‹ ͷ Ƭ‹‘–””œ›„›•œ ͷǡ͸ Š‡’”‘’‡”–‹‡•‘ˆ’ƒ’‡”’”‘†— –•†‡’‡†‘–Š‡•–”— –—”‡‘ˆ–Š‡ ‡ŽŽ—Ž‘•‡Ƥ„”‡•–Š‡”‡‹ǤŽ–Š‘—‰Š Ƥ„”‡’”‘’‡”–‹‡•‹˜‹”‰‹’—Ž’• ƒ„‡‘†‹Ƥ‡†„›ƒ”‡Ƥ‹‰’”‘ ‡••ǡ–Š‹•‹•‘”‡†‹ƥ —Ž–‹’—Ž’ ˆ”‘”‡ ‘˜‡”‡†Ƥ„”‡ǡ’ƒ”–‹ —Žƒ”Ž›™ƒ•–‡ˆ”‘‘ƥ ‡•Š”‡††‡”•–Šƒ––‡†–‘•Š‘”–‡Ƥ„”‡•†—”‹‰ •Š”‡††‹‰ǤŠ‡•Š‘”–‡”Ƥ„”‡•‹•Š”‡††‡†’ƒ’‡”ƒ‡‹–†‹ƥ —Ž––‘‡ƒ•‹Ž›”‡ ‘•–‹–—–‡–Š‡‹–‘Š‹‰ŠǦ “—ƒŽ‹–›’ƒ’‡”’”‘†— –•Ǥ‘”‡‘˜‡”ǡ„‡ ƒ—•‡‘ˆŠ‹‰Š‡‡”‰›—•ƒ‰‡†—”‹‰–Š‡”‡ › Ž‹‰’”‘ ‡••ƒ† –”ƒ•’‘”–ƒ–‹‘‹‡ƥ ‹‡ ‹‡•ǡ–Š‡”‡‹•ƒ‡‡†–‘†‡–‡”‹‡Š‘™–‘”‡•’‘•‹„Ž›•Š”‡†’ƒ’‡”–‘ƒŽŽ‡˜‹ƒ–‡ –Š‹•‡˜‹”‘‡–ƒŽ„—”†‡Ǥ‹–Š–Š‹•‹‹†ǡ–Š‡‹ƪ—‡ ‡‘ˆ‹‹–‹ƒŽƤ„”‡Ž‡‰–Š‘–Š‡–‡•‹Ž‡ ’”‘’‡”–‹‡•‘ˆ’ƒ’‡”™ƒ•‹˜‡•–‹‰ƒ–‡†ǤŠƒ‰‡•‹‹‹–‹ƒŽƤ„”‡Ž‡‰–Š•‹‰‹Ƥ ƒ–Ž›‹ƪ—‡ ‡†ƒ› ’—Ž’ƒ†’ƒ’‡”’”‘’‡”–‹‡•Ǥ –™ƒ•ˆ‘—†–Šƒ– —––‹‰–Š‡’ƒ’‡”‹–‘’‹‡ ‡•™‹–Šƒƒ”‡ƒŽ‡••–Šƒ͸ͻ   ͸  ƒ—•‡†•‹‰‹Ƥ ƒ– Šƒ‰‡•‹–Š‡‹’‘”–ƒ–‘”’Š‘Ž‘‰‹ ƒŽ’ƒ”ƒ‡–‡”•‘ˆ–Š‡Ƥ„”‡•ƒ†ƒ•Šƒ”’ †‡ ”‡ƒ•‡‹–Š‡–‡•‹Ž‡’”‘’‡”–‹‡•‘ˆ–Š‡”‡ ‘•–‹–—–‡†’ƒ’‡”Ǥ Wastepaper, for both ecological and economic reasons, is a good raw material for the production of paper or cardboard. Paper recycling reduces the use of wood, and thus, helps preserve forest resources, saves energy, reduces littering, the amount of waste going to landfills, air pollution, and wastewater generation, and instils ecological attitudes in society. However, the properties of fibres in wastepaper can deteriorate not only during processing, but also at the col- lection stage due to shredding, which can cause excessive shortening of the fibres. In addition to fibre bonding 1 , fibre length and strength are basic factors influencing the tensile and structural properties of paper products 2–4 . Fibre and pulp properties also affect the cost of producing paper products. Hence, the ability to control fibre properties during the recycling stage is a determining factor in effective quality control and the cost of paper production from waste paper. In industrial practice, the fibres are shortened as a direct result of the fibre refining process or by high-shear processing of the fibrous suspension in the refining zone 5,6 . Therefore, the process of pulp refining has a direct influence on fibre properties, and consequently the properties of the final product 7–9 . Through refining, the properties of the refined pulp can be modified to obtain paper with the desired properties. The refining pro- cess, aside from affecting paper properties, also has a decisive impact on the unit energy consumption in this process 10–13 . Owing to the increasing global growth of the market for paper products 14,15 , it is extremely important to minimise the unit energy consumption in this process and optimise the development of useful properties of the paper during processing. Changes taking place in the structure of the refined fibres during the refining process determine how the pulp behaves during web formation and the basic properties of the paper that is produced 16,17 . Fibre shortening has a direct negative impact on the dynamic properties of paper, including its tear resistance 18,19 . Often, refining is consciously carried out to improve the conditions of web forming and improve its transparency. When paper is thrown into shredders, the objective is to destroy documents; however, the process also uncon- sciously shortens the fibres. Paper shredders should facilitate the preparation of pulped materials for further production, rather than render the paper useless. Cut fibres in the shredded paper make it difficult to carry out easy reconstitution into high-quality paper products. Moreover, most recycling centres do not handle small strips or bits of paper. Large-scale recycling facilities use large screens to dry pulped paper on, and finely shredded paper is not well retained and can fall through the screens. Reports claim that the utilisation or recycling of shredded paper is much more problematic than that of mixed unshredded paper. The Environmental Paper Network, a worldwide association of 140 civil society groups and NGOs concerned with the sustainability of pulp and paper



ͷ ƒ–—”ƒŽ ‹„‡”•†˜ƒ ‡†‡ Š‘Ž‘‰‹‡•ǡͺ͸Ž‡‹–ƒ–”ǤǡͿ͹Ǧ͹͸͸‘†œǡ‘Žƒ†Ǥ ͸ •–‹–—–‡‘ˆ‘‘† ‹‡ ‡•ƒ† —”‹–—”‡ǡƒ”•ƒ™‹˜‡”•‹–›‘ˆ‹ˆ‡ ‹‡ ‡•Ǧ ǡͷͻͿ‘™‘—”•›‘™•ƒ–”ǤǡͶ͸Ǧͽ;ͽƒ”•ƒ™ǡ‘Žƒ†Ǥ * email: ‡†›–ƒ̸ ƒŽƒ Š‘™•ƒ̻ •‰‰™Ǥ‡†—Ǥ’Ž

 ‹‡–‹Ƥ ‡’‘”–• |

(2021) 11:17528

| Š––’•ǣȀȀ†‘‹Ǥ‘”‰ȀͷͶǤͷͶ͹;Ȁ•ͺͷͻͿ;ǦͶ͸ͷǦͿͼ͹͸ͻǦͺ

ͷ

‘ŽǤǣȋͬͭͮͯ

ͰͱͲͳʹ͵Ȍ

Made with FlippingBook Online document maker