Vpliv temperature in trajanja postopka termične modifikacije lesa na fungicidne lastnosti modificiranega lesa

diplomsko delo - univerzitetni študij

Niko Štabuc (Author), Franc Pohleven (Reviewer), Miha Humar (Mentor), Boštjan Lesar (Co-mentor)

Abstract

Termična modifikacija je eden izmed komercialno najuspešnejših postopkov modifikacije. Pomemben kazalnik kakovosti termične modifikacije lesa je izguba mase, ki je funkcija časa in temperature izpostavitve. Ugotavljali smo, kateri parameter bolj vpliva na odpornost lesa na glive razkrojevalke. Vzorce bukovine, ki so bili 1, 1,5; 2; 3; 4; 6; 8; 16; 36 ur termično modificirani pri temperaturi 180 °C in 220 °C, smo izpostavili glivi Trametes versicolor. Smrekovino, ki je bila 1, 1,5; 2; 3; 4; 6; 10; 16; 36; 72 ur termično modificirana pri temperaturi 180 °C in 220 °C, smo izpostavili glivi Gloeophyllum trabeum. Po 16 tednih izpostavitve vzorcev glivam smo z gravimetrično metodo določili izgubo mase in jo primerjali z izgubo mase med samim postopkom termične modifikacije. Ugotovili smo, da je odpornost lesa proti glivam v linearni povezavi z izgubo mase, nastale med postopkom termične modifikacije. Kako pridemo do izgube mase med termično modifikacijo (daljši čas in nižja temperatura ali krajši čas in višja temperatura) ni pomembno, saj je odpornost proti glivam primerljiva. Pri modifikaciji pri nižji temperaturi (180 °C) ne dosežemo dovolj velikih stopenj modifikacije, da bi les ustrezno zaščitili. Vpliv postopkov termične modifikacije na kratkotrajne navzeme vode smo določali s tenziometrom, in ugotovili, da so vzorci z višjo stopnjo modifikacije bolj hidrofobni.

Keywords

les;termična modifikacija;temperatura;odpornost;navzem;

Data

Language:	Slovenian
Year of publishing:	2012
Source:	Ljubljana
Typology:	2.11 - Undergraduate Thesis
Organization:	UL BF - Biotechnical Faculty
Publisher:	[N. Štabuc]
UDC:	630*844
COBISS:	2020233
Views:	852
Downloads:	236
Average score:	0 (0 votes)
Metadata:

Other data

Secondary language:	English
Secondary title:	Influence of temperature and duration of thermal modification process on fungicidal properties of modified wood
Secondary abstract:	Thermal modification is one of the commercially most successful modification processes. One of the main parameters of quality of thermally modified wood is the loss of mass during the process, which is a function of time and temperature. We examined which parameter has more influence on wood resistance to fungus decay. Samples of beech were thermally modified at temperatures 180 °C and 220 °C for 1; 1,5; 2; 3; 4; 6; 8; 16; 36 hours, and exposed to Trametes versicolor. Samples of spruce were thermally modified at the same temperatures for 1; 1,5; 2; 3; 4; 6; 10; 16; 36; 72 hours, and exposed to Gloeophyllum trabeum. After 16 weeks of exposure to the fungi, the loss of mass was determined with a gravimetric method, and compared to the loss of mass caused by thermal modification process. The resistance of wood against decay caused by fungi is linearly correlated with the loss of mass due to thermal modification. It is not important how mass loss during the thermal modification is obtained (longer time and lower temperature or shorter time and higher temperature) the resistance to fungi being comparable. Using thermal modification at lower temperature (180 °C) we cannot achieve adequate modification to sufficiently protect the wood against fungi. The effect of thermal modification processes on short term absorption of water was determined with tensiometer; the samples with a higher level of modification were more hydrophobic.
Secondary keywords:	wood;thermal modification;temperature;resistance;sorption;
Type (COBISS):	Undergraduate thesis
Thesis comment:	Univ. v Ljubljani, Biotehniška fak., Oddelek za lesarstvo
Pages:	X, 49 f.
Keywords (UDC):	applied sciences;medicine;technology;uporabne znanosti;medicina;tehnika;agriculture and related sciences and techniques;forestry;farming;wildlife exploitation;kmetijstvo ter sorodne vede in tehnologije;forestry;gozdarstvo;forest products and their utilization;gozdni proizvodi in njihova uporaba;
ID:	22099