scholarly journals Characterisation of Wood Particles Used in the Particleboard Production as a Function of Their Moisture Content

Materials ◽  
2021 ◽  
Vol 15 (1) ◽  
pp. 48
Author(s):  
Dorota Dukarska ◽  
Tomasz Rogoziński ◽  
Petar Antov ◽  
Lubos Kristak ◽  
Jakub Kmieciak

The properties of particleboards and the course of their manufacturing process depend on the characteristics of wood particles, their degree of fineness, geometry, and moisture content. This research work aims to investigate the physical properties of wood particles used in the particleboard production in dependence on their moisture content. Two types of particles currently used in the production of three-layer particleboards, i.e., microparticles (MP) for the outer layers of particleboards and particles for the core layers (PCL), were used in the study. The particles with a moisture content of 0.55%, 3.5%, 7%, 10%, 15%, and 20% were tested for their poured bulk density (ρp), tapped bulk density (ρt), compression ratio (k), angle of repose (αR), and slippery angle of repose (αs). It was found that irrespective of the fineness of the particles, an increase in their moisture content caused an increase in the angle of repose and slippery angle of repose and an increase in poured and tapped bulk density, while for PCL, the biggest changes in bulk density occurred in the range up to 15% of moisture content, and for MP in the range above 7% of moisture content, respectively. An increase in the moisture content of PCL in the range studied results in a significant increase in the compression ratio from 47.1% to 66.7%. The compression ratio of MP increases only up to 15% of their moisture content—a change of value from 47.1% to 58.7%.

Author(s):  
P. C. Vengaiah ◽  
S. Kaleemullah ◽  
M. Madhava ◽  
A. Mani ◽  
B. Sreekanth

Some physical properties of palmyrah fruit were investigated in this study. The average values of major, medium, minor and geometric mean diameters of fresh whole palmyrah fruit were 11.54,10.45, 9.85 and 10.64 cm respectively at 47.34 % (w.b) moisture content whereas that of palmyrah nut were 8.59, 7.35, 4.99 and 6.79 cm respectively at 8% (w.b) moisture content. Sphericity, surface area and aspect ratio were found to be 91.94%, 359.17 cm2 and 0.90 for fruit and whereas that of nut were 79.19%, 145.16 cm2 and 0.86 respectively. The average mass of the individual palmyrah fruit and nut was 927.78 and 248.10 g whereas bulk density was 525.92 and 693.0 kg/m3 respectively. The coefficient of static friction on mild steel, glass and plywood surfaces were 0.27, 0.21 and 0.25 for palmyrah fruit and 0.36, 0.28 and 0.27 for nut respectively. The angle of repose of palmyrah fruit and nut were 30.77 and 44.03 respectively.


2009 ◽  
Vol 55 (No. 4) ◽  
pp. 165-169 ◽  
Author(s):  
M.C. Ndukwu

The research looked at some selected physical properties of <I>Brachystegia eurycoma</I>, such as axial dimension, roundness, sphericity, surface area, bulk density, solid density, porosity, and volume which are essential in the design and construction of the processing and handling equipments of <I>Brachystegia eurycoma</I>. All the above physical properties measured showed some deviations from the average values which is typical of agricultural biomaterials. Solid density showed the highest deviation of 4.04 g/mm<sup>3</sup> while the volume showed the least deviation of 0.01 mm<sup>3</sup> when compared to those of other physical properties. The angle of repose increased with the increase in the moisture content with a coefficient of determination of 0.98.


2016 ◽  
Vol 44 (2) ◽  
Author(s):  
Shrikant Baslingappa Swami ◽  
N.J. Thakor A.M. Gawai

<p>The physical properties, viz., geometric diameter, surface area, sphericity, volume, bulk density, true density and angle of repose was measured for  four  cashew varieties <em>viz</em>., <em>Vengurle 1, Vengurle 3, Vengurle 4</em>  and <em>Vengurle 7</em> at different moisture content (15 to 87% db). For <em>Vengurle</em> 1 as the moisture content increased, the physical properties i.e., geometric mean diameter, volume, surface area, true density and angle of repose increased from 20.8 to 22.1 mm, 3485 to 4416 mm<sup>3</sup>, 1355 to 1540 mm<sup>2</sup>, 984 to 1030 kg m<sup>-3</sup> and 32 to 37˚, respectively. The sphericity and bulk density decreased from 74.2 to 71.4 per cent and 490 to 418 kg m<sup>-3</sup> respectively. For <em>Vengurle 3</em> geometric mean diameter, volume, surface area, true density and angle of repose increased from 27.2 to 28.6 mm, 7912 to 9169 mm<sup>3</sup>, 2320 to 2567 mm<sup>2</sup>, 1020 to 1048 kg m<sup>-3</sup> and 33 to 35.5˚, respectively. The sphericity and bulk density decreased from 75.5 to 75.2 per cent and 531 to 470 kg m<sup>-3</sup> respectively. For <em>Vengurle 4</em> the geometric mean diameter, volume, surface area, true density and angle of repose increased from 21.0 to 24.1mm, 3362 to 5113 mm<sup>3</sup>, 1391 to 1828 mm<sup>2</sup>, 970 to 1030 kg m<sup>-3</sup> and 32.5 to 38˚,  respectively. The sphericity and bulk density decreased from 65.8 to 66.8 per cent, 517 to 462 kg m<sup>-3</sup>, respectively. For <em>Vengurle 7</em> the geometric mean diameter, volume, surface area, true density and angle of repose increased from 24.2 to 24.9 mm, 5102 to 5547 mm<sup>3</sup>, 1840 to 1941 mm<sup>2</sup>, 998 to 1045 kg m<sup>-3</sup> and 33 to 38˚, respectively. The sphericity and bulk density decreased from 65.4 to 65.8 per cent, 518 to 438 kg m<sup>-3</sup>, respectively.</p>


2017 ◽  
Vol 4 (1) ◽  
pp. 25-30
Author(s):  
Muhammad Navis Rofii ◽  
Satomi Yumigeta ◽  
Shigehiko Suzuki ◽  
Tibertius Agus Prayitno

Wood waste materials such as flakes, particles, sawdust, planer shaving, which are residues from furniture industry can be utilized to manufacture many composites such as particleboard. The most commonly used particleboard has three layers: two face layers and one core layer. The face layers consist of fine particles and the core layer is made of coarse particles.This study aimed to show the effect of shelling ratio and particle characteristic on physical properties of three-layer particleboard with high density core and different particles on surface layers. The materials used in this study were hinoki (Chamaecyparis obtusa) strand and knife-milled Douglas-fir (Pseudotsuga manziesii) as surface layers and hammer-milled matoa (Pometia sp.) as core layer. The wood particles were collected from a wood company. Adhesive used was MDI resin (methylene diphenyl diisocyanate) with 6 % content in mat preparation. The pressing conditions were: temperature 180°C, pressure  3 MPa and pressing time  5 min. The target density was 0.72 g/cm3 with board size of 340 mm x 320 mm  x 10 mm. Factors used in this study were layer structure according to board shelling ratio and particle characteristic. The parameters of this study were density, moisture content, thickness swelling, water absorption, linear expansion and vertical density profile.The results of this study indicate that all boards meet the requirements of JIS A 5908-2003. Higher shelling ratio of surface layers resulted in higher physical performance of three-layer particleboard. In terms of particle type, hinoki strands showed the best performance in board density and linear expansion, while Douglas-fir particle showed the best performance in moisture content, thickness swelling and water absorption. Improvement of physical properties of particleboard with high density wood particles in core layer can be conducted by adding surface layer with higher quality wood particles such as hinoki strands or Douglas-fir particles. Compared to Douglas-fir particles, hinoki strands as surface layers contribute to higher enhancement of three-layer particleboard with matoa as the core layer.


2018 ◽  
Vol 34 (6) ◽  
pp. 1017-1026 ◽  
Author(s):  
Fuji Jian ◽  
Sam Yavari ◽  
Ramasamy Boopathy Narendran ◽  
Digvir S. Jayas

Abstract.Physical properties of hemp seeds (, L., cultivar Finola®) with 5%, 10%, and 15% foreign materials and dockages (FMD) at 9%, 12%, and 15% moisture contents (wet basis) were measured. The measured and determined physical properties include physical dimensions (length, width, thickness, kernel volume, sphericity, and average surface area), density (bulk and true density), porosity, weight of 1000 kernels, filling and empting angles of repose, and coefficients of friction on surfaces of plywood, galvanized steel, steel-troweled concrete, and wood-floated concrete. The mean value of the length, width, and thickness of the 50 kernels had a linear relationship with the increase of moisture content; however, this was not true for individual kernels. Bulk density of seeds at any FMD level decreased linearly or quadratically with the moisture content increase, while the true density had an opposite trend. Increasing FMD significantly increased the bulk density at any moisture content, and there were variations for the true density. There were gaps between the seed coat and cotyledon, and these gaps became smaller or disappeared when the seed moisture content was increased. This phenomenon resulted in the same average surface area, same volume, and exponential increase in porosity to 58.5% with the increase of moisture content. Increased FMD significantly decreased the porosity at any moisture content. Emptying angle of repose increased with the increase of moisture contents and percentage of FMD. Higher variability was observed in the filling angle of repose than in the emptying angle of repose. The coefficient of friction was the largest against wood-floated and steel-troweled concrete, followed by galvanized steel, and the smallest was against the plywood surface. Keywords: Angle of repose, Density, Foreign material and dockage (FMD), Friction against structural surface, Hemp seed, Physical dimensions.


2016 ◽  
Vol 824 ◽  
pp. 100-107 ◽  
Author(s):  
Alena Struhárová

Bulk density and moisture content are factors that significantly affect the physical properties of autoclaved aerated concrete (AAC) including thermal conductivity and other thermo-technical characteristics. This article shows the results of measurements of compressive strength, capillary absorption, water absorption and porosity of AAC (ash on fluidized fly ash) at different bulk density and also the results of thermal conductivity of AAC at different bulk density and variable moisture content of the material. The thermo-technical properties were measured using the Isomet 2104, a portable measuring device. Acquired results demonstrate dependence of physical properties including thermal conductivity of AAC on bulk density and moisture content. The reliability and accuracy of the method of measuring was also shown.


2013 ◽  
Vol 2 (6) ◽  
pp. 24
Author(s):  
A. S. Oyerinde ◽  
A. P. Olalusi

<p>The effect of moisture content on some physical and mechanical properties of two varieties of tigernuts (<em>Cyperus esculentus</em>) was investigated. These properties include: geometric dimensions, linear dimensions, 1000 tuber weight, bulk density, tuber size, sphericity, angle of repose, porosity, coefficient of static friction and compressive strength. The moisture content levels used were 20, 25, 30, 35 and 40% wet basis (wb), and the two tigernut varieties used were yellow and brown types. The linear dimension, geometric diameter, sphericity, 1000- tuber weight, bulk density and angle of repose in both varieties increased with increasing moisture content. The average length, width and thickness of the yellow variety increases more than the brown variety at the determined moisture contents. True density of the yellow variety increased while the brown variety decreased with increase in moisture content. The porosity of the yellow variety reduces with increase in moisture content from 45.95 at 20% mc to 42.4 at 40% mc, while the brown variety decreased from 42.72 at 20% mc to 30.77 at 40% moisture content. The yellow variety had bigger size tubers than the brown variety and this has serious implications in packing, handling and transportation issues.</p>


2011 ◽  
Vol 6 (No. 2) ◽  
pp. 73-82 ◽  
Author(s):  
S.E. Obalum ◽  
J.C. Nwite ◽  
J. Oppong ◽  
C.A. Igwe ◽  
T. Wakatsuki

One peculiar feature of the inland valleys abundant in West Africa is their site-specific hydrology, underlain mainly by the prevailing landforms and topography. Development and management of these land resources under the increasingly popular sawah (a system of bunded, puddled and levelled rice field with facilities for irrigation and drainage) technology is a promising opportunity for enhancing rice (Oryza sativa L.) production in the region. Information on the variations in selected soil physical properties as influenced by the prevailing landforms may serve as a useful guide in site selection. This is of practical importance since majority of the inland valleys are potentially unsuitable for sawah development and most farmers in the region are of low technical level. Three landforms (river levee, elevated area and depressed area) were identified within a sawah field located in an inland valley at Ahafo Ano South District of Ghana. Each of these landforms was topsoil-sampled along on identified gradient (top, mid and bottom slope positions). Parameters determined included particle size distribution, bulk density, total porosity and field moisture content. The soil is predominantly clayey. There were no variations in the particle size distribution among the slope positions in the river levee. Overall, the river levee had lower silt content than the elevated and the depressed landforms. The bulk density, total porosity, and gravimetric moisture content indicated relative improvements only in the depressed area in the order, bottom &gt; mid &gt; top slope. Irrespective of slope position, the three landforms differed in these parameters in the order, depressed &gt; river levee &gt; elevated. The sand fraction impacted negatively on the silt fraction and bulk density of the soil, both of which controlled the soil moisture status. Despite the fairly low silt content of the soil, the silt fraction strongly influenced the gravimetric moisture content (R<sup>2</sup> = 0.80). So too did the soil bulk density on the gravimetric moisture content (R<sup>2</sup> = 0.90). It is concluded that: (1) since the landforms more prominently influenced the measured parameters than the slope positions, the former should take pre-eminence over the latter in soil suitability judgment; (2) with respect to moisture retention, variations in silt fraction and bulk density of this and other clayey inland-valley soils should be used as guide in site selection for sawah development.


Author(s):  
Bhabani Shankar Dash ◽  
Sangram Keshari Swain ◽  
Debaraj Behera ◽  
Kalpana Rayaguru ◽  
Megha Meshram

Background: Green gram is a popular pulse crop in India (with 2.02 MT production over a cultivated area of 4.26 Mha) and Odisha (20.8 lakh ha area with a yield of 10.60 lakh tonnes). The information on the engineering properties and its behavioural changes with moisture content is vital for handling and designing of different agricultural processing equipment. Methods: This work mainly focused on studying green gram variety’s (Sujata) engineering properties at five different moisture levels (within a moisture range of 10.58 to 45.45% (d.b.). Standard methods and procedures were followed in the study and the output results were compared with previous research work to justify the variation or anomaly in some cases. The curve estimation method (regression analysis) was followed to find the best-fit curve and equation for the parameters studied. Result: The geometric mean diameter (GMD) of grain increased from 3.75 to 4.12 mm within the moisture content (MC) range and the variation was statistically significant (p less than 0.05). Sphericity and surface area varied significantly from 0.83 to 0.82 and 44.13 to 53.45 mm2, respectively, within the range of moisture contents studied with a high correlation among the data. Mass of thousand grains augmented (44.13 to 53.45 g) with a rise in MC and the data followed logarithmic and inverse curves. Bulk and true densities of green gram declined significantly from 860 to 670 kg m-3 and 1330 to 1240 kg m-3 with an increase in the moisture content. The porosity of green gram increased significantly from 35.75% to 46.38% and the terminal velocity raised from 9.20 m s-1 to 11.10 m s-1 with an increase in MC. The dynamic angle of repose increased significantly from 30.95 to 46.57o with MC. A significant variation in the coefficient of internal friction (0.78 to 0.90) was observed for the grains. The coefficient of static friction of grain increased significantly for different surfaces (MS, SS, Plywood and GI) with a rise in MC. The MS surface produced the highest coefficient of static friction and SS had the least. The results confirmed significant effect of MC on all engineering properties of green gram.


Author(s):  
Ryszard Oleszczuk ◽  
Milena Truba

Abstract The analysis of some physical properties of drained peat-moorsh soil layers. The paper presents the results of measurements of some physical properties for 14 drained fen peat-moorsh layers (degree of decomposition, bulk density, particle density, porosity and saturated moisture content). The soil samples were taken from north- -east, central and east part of Poland. These areas were drained in order to use as a grassland and meadows. The article presents obtained data of selected physical properties from several drained peatlands in Poland and shows the comparison of established results with relevant data published in literature.


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