Temperature-drop sensor for determination of drying curves in conventional lumber drying
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Diego Elustondo
Abstract
Conventional lumber drying is carried out by forcing hot air to flow across a pile of lumber layers separated by wood strips. The airflow provides the heat required to warm up the lumber and produce the moisture evaporation and, in theory, the difference in temperature at each side of the load can be used to estimate the evaporation rate. The main problem with this approach is that typical temperature sensors that are installed in conventional kilns are not accurate enough to measure the temperature drop across the load during periods of low evaporation. In this paper, a new sensor to measure the temperature drop across the load is proposed and tested in three experimental drying runs of 2″×6″ spruce-pine lumber. The results demonstrate that after calibration, the temperature drop across the load can be used to determine drying curves in conventional lumber drying. In the particular case of this study, calibration was performed by multiplying the experimental temperature drop across the load by a constant factor, which was adjusted by identifying the correction factor that best simulated the experimental green moisture content of the three lumber charges.
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©2006 by Walter de Gruyter Berlin New York
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Articles in the same Issue
- The influence of lignin chemistry and ultrastructure on the pulping efficiency of clonal aspen (Populus tremuloides Michx.)
- Elucidating carboxylic acid profiles for extended oxygen delignification of high-kappa softwood kraft pulps
- A selectivity study of reaction of the carbonate radical anion with methyl β-d-cellobioside and methyl β-d-glucoside in oxygenated aqueous solutions
- Evidence for the formation of lignin-hexenuronic acid-xylan complexes during modified kraft pulping processes
- The effect of molecular composition of xylan extracted from birch on its assembly onto bleached softwood kraft pulp
- Critical comparison of methods for surface coverage by extractives and lignin in pulps by X-ray photoelectron spectroscopy (XPS)
- Characterisation of lignin-carbohydrate complexes (LCCs) of spruce wood (Picea abies L.) isolated with two methods
- Characterization of lignin-carbohydrate complexes from spruce sulfite pulp
- Lignin antioxidants for preventing oxidation damage of DNA and for stabilizing polymeric composites
- Glycerol-ω-hydroxyacid-ferulic acid oligomers in cork suberin structure
- Improvement of formaldehyde-scavenging ability of condensed tannins by ammonia treatment
- Yield and composition of lipophylic extracts of yellow birch (Betula alleghaniensis Britton) as a function of wood age and aging under industrial conditions
- Transverse anisotropy of compressive failure in European oak – a digital speckle photography study
- Temperature-drop sensor for determination of drying curves in conventional lumber drying
- Preparation of acetoacetylated wood meal and its properties. Part 1. Preparation of parameter and preliminary evaluation of the antifungal activity
- Preparation of acetoacetylated wood meal and its properties. Part 2. Copper ion fixation by acetoacetylation
- Treatment of wood with aminofunctional silanes for protection against wood destroying fungi
- Detection of fungal decay by high-energy multiple impact (HEMI) testing
