التفاصيل البيبلوغرافية
| العنوان: |
Wood impregnation with bark polyphenols ; Puun kyllästäminen puun kuoren polyfenoleilla |
| المؤلفون: |
Tuominen, Lauri |
| المساهمون: |
Lappeenrannan-Lahden teknillinen yliopisto LUT, Lappeenranta-Lahti University of Technology LUT |
| سنة النشر: |
2023 |
| المجموعة: |
LUTPub (LUT University / LUT yliopisto) |
| مصطلحات موضوعية: |
Alkaline extraction, Polyphenols, tannins, wood impregnation, bark, alkaliuutto, polyfenolit, tanniinit, puun painekyllästys, kuori, fi=Kestävä kehitys|en=Sustainable development, fi=School of Engineering Science, Kemiantekniikka|en=School of Engineering Science, Chemical and Process Engineering |
| الوصف: |
Wood impregnation with alkaline extracted polyphenols from Norway spruce (Picea abies) bark was studied in this master thesis. Wood bark is an important side stream of forestry. Compared to stem wood, bark contains large amounts of extractives, like tannins and other polyphenols, which protect wood naturally. Bark is utilized often directly as energy, but chemicals extracted from it can be also used in many other applications. Alkaline extraction is an efficient way to extract polyphenols from bark. Chemicals are absorbed into wood structure under high pressures in pressure impregnation of wood. Those chemicals protect wood for instance from microbial attack. Many of the chemicals used in pressure impregnation of wood are non-renewable and harmful but they can be replaced by renewable ones. Pressure impregnation process of Scots pine (Pinus sylvestris) using a polyphenol-rich alkaline extract, black liquor, from Norway spruce bark as preservative was optimized in the experimental part of this work. Best results in laboratory scale experiments were achieved with steaming pre-treatment and carrying out impregnation for 120 minutes in 9 bar pressure. Impregnation experiments were performed also with silver birch (Betula pendula), which was possible to impregnate using lower pressures than for Scots pine. Most of the impregnation occurred vertically along the wood cells. Black liquor fractionated to lower molecular size fractions with membrane separation was however efficient in terms of tangential and radial penetration in the impregnation. The biggest challenge in the experiments was the water solubility of the polyphenols since most of them were leached out during leaching experiments. Mould resistance of impregnated wood was also bad, impregnation did not inhibit the mould growth in the surfaces of the wood. ; Tässä diplomityössä tutkittiin puun kyllästämistä metsäkuusen (Picea abies) kuoresta alkaliuutolla erotetuilla polyfenoleilla. Puun kuori on metsäteollisuuden tärkeä sivuvirta. Runkopuuhun verrattuna kuori ... |
| نوع الوثيقة: |
master thesis |
| وصف الملف: |
fulltext |
| اللغة: |
English |
| Relation: |
https://lutpub.lut.fi/handle/10024/166614; URN:NBN:fi-fe20231128149593 |
| الاتاحة: |
https://lutpub.lut.fi/handle/10024/166614 |
| Rights: |
fi=Kaikki oikeudet pidätetään.|en=All rights reserved.| |
| رقم الانضمام: |
edsbas.8A02280C |
| قاعدة البيانات: |
BASE |