Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

Wyszukujesz frazę "wilgotnosc drewna" wg kryterium: Temat


Wyświetlanie 1-2 z 2
Tytuł:
Naturalne suszenie surowca drzewnego w miejscu pozyskania
Natural drying of wood in the cutting area
Autorzy:
Tomczak, A.
Jelonek, T.
Leszczyński, N.
Korzeniewicz, R.
Powiązania:
https://bibliotekanauki.pl/articles/988961.pdf
Data publikacji:
2017
Wydawca:
Polskie Towarzystwo Leśne
Tematy:
lesnictwo
uzytkowanie lasu
surowce drzewne
drewno swiezo sciete
masa drewna
wilgotnosc drewna
suszenie naturalne
magazynowanie
biomass
energy wood
industrial wood
storage
moisture content
Opis:
Wood obtained from freshly cut trees has a high moisture content and therefore its mass per volume unit is higher than the mass of dry wood. The natural drying is a simple and effective method of weight (moisture content) reduction, making a better use of the vehicle's payload, and thus reducing costs, including environmental costs. The conclusion is based on simulations and analyzes attempting to evaluate different solutions. As evidenced, the drying process of logs depends on numerous factors, which entails attempts at development of an optimal logging method, especially concerning energy wood, allowing for maximum value growth in as little time as possible. The suggestions cover various forms of logging (of whole trees, long timber), arranging (in piles, bundles), storing (in stands, by the roadside near cutting areas), and protection. Combined methods such as storing under canvas for winter only or storing in cutting areas and later in piles at the exit road also work in practice, but require more funds because their cost is determined by the number of stages composing the whole process. In case of wood, development of an optimal and simultaneously universal method used to prepare the lumber for transport and its delivery with consideration of as little environmental impact as possible is complicated. The numerous variables, some of which cannot be controlled or affected, create a considerable scientific problem as well. The authors covered in the presented literature review often stress the role of specific weather conditions accompanying an experiment or its location, the storage method, or lumber dimensions in the drying process. Storage time is perceived as equally important, but it is a derivative more or less determined by the previous variables. Previous studies of drying at the cutting area have been focused mainly on energy wood and less on industrial wood. They analysed the results of long−term storage and did not stress the potential advantages of short−term drying. Furthermore, we do not have sufficient information on species, including forest trees, which have a lower share in the volume of the logged wood. Advanced research can help establish the minimum mass (moisture content) with considerable impact on supply chain effectiveness improvement or evaluated various storing and drying methods. We reviewed reports explaining the impact of various factors on natural drying of wood, models and storage effects, and analyzing potential economic and environmental benefits.
Źródło:
Sylwan; 2017, 161, 11; 898-908
0039-7660
Pojawia się w:
Sylwan
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Wpływ wilgotności i gatunku drewna opałowego na przebieg procesu łupania
Effect of humidity and species of firewood on the course of cleaving
Autorzy:
Brzózko, J.
Samoraj, P.
Błuszkowska, U.
Aniszewska, M.
Powiązania:
https://bibliotekanauki.pl/articles/987080.pdf
Data publikacji:
2017
Wydawca:
Polskie Towarzystwo Leśne
Tematy:
drewno opalowe
grab pospolity
Carpinus betulus
drewno grabowe
buk zwyczajny
Fagus sylvatica
drewno bukowe
brzoza brodawkowata
Betula pendula
drewno brzozowe
olsza czarna
Alnus glutinosa
drewno olszowe
jesion wyniosly
Fraxinus excelsior
drewno jesionowe
wilgotnosc drewna
lupanie
luparka SplitMaster 9
wydajnosc pracy
wood splitting
solid biofuels
wood moisture
Opis:
Traditional firewood is still the most popular type of solid fuel. This is mainly because of the availability of raw materials and simple production process, which involves mostly just sawing and cleaving. Cleaving increases the surface of the wood through which water evaporates, which in turn speeds up the drying. Dry wood has a higher calorific value and its combustion releases less harmful carbon monoxide and hydrocarbons. Wood cleaving process can be divided into three phases that lasts from the introduction of the wedge till the appearance of a crack (phase I), from the appearance of the crack till the stop of the slots (phase II) and then until the piece of the wood is completely cleaved (phase III). Although it is a conditional phase and it does not always occur in the case of the firewood species popular in Poland, the last phase takes the longest and has the greatest impact on the cleaving performance. The aim of the study was to determine the effect of wood and its moisture content on the duration of the phase III during the trial cleaving. The tested samples comprised of five popular in Poland species: hornbeam, beech, birch, alder and ash. The cleaving were carried out immediately after cutting and sawing the timber and after 3−month−long period of natural drying. For hornbeam, beech and alder humidity does not affect the hollow wedge in wood at the time of rupture. The duration of phase III was significantly longer than duration of phases I and II for each species independently of humidity. Significant dependence was observed for depression wedge as a function of humidity obtained in phase I and II for silver birch, and in phase III for ash.
Źródło:
Sylwan; 2017, 161, 08; 685-692
0039-7660
Pojawia się w:
Sylwan
Dostawca treści:
Biblioteka Nauki
Artykuł
    Wyświetlanie 1-2 z 2

    Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies