• Journal of the Korean Wood Science and Technology
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• v.27 no.2
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• pp.70-77
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• 1999

Objective of this research is to obtain fundamental data of carbonized wood wastes for soil condition, de-ordorization, absorption of water, carrier for microbial activity, and purifying agent for water quality of river. The carbonization technique and the properties of carbonized wood wastes(thinned trees) are analyzed. Proximate analysis shows the thinned wood contains 0.22-0.73% ash, 77-80% volatile matter, and 10-14% fixed carbon. The charcoal yield decreases and the shrinkage rate increases as the carbonization temperature and time increase. The charcoal yields of Larix leptolepis, Pinus rigida and Pinus densiflora are high, whereas those of Pinus koraiensis and Quercus variabilis are low. The shrinkage rate by carbonization has same trend as water removal of wood. The specific gravity after the carbonization decreases about 50% comparing to green wood. The charcoal has 0.89-4.08% ash, 6.31-13.79% volatile matter, and 73.9-83.5% fixed carbon. As the carbonization temperature and time increase, pH of charcoal increases. When the carbonization temperature is $400^{\circ}C$, pH is about 7.5. When the temperature is between 600 to $800^{\circ}C$, pH is about 10 with small difference. The water-retention capacity is not affected by the carbonization temperature and time. The water-retention capacity within 24hr is about 2.5 - 3times of sample weight, and the equivalent moisture content becomes 2-10% after 24 hr.

• Journal of Conservation Science
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• v.24
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• pp.57-66
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• 2008

It is reported that excavated carbonized wooden objects tend to have more peeling and deformation stemming from the coexisting of different types of parts of objects. However, there is little research results on this. In this experiment, the sugar alcohol method was used and then compared with the results of the PEG4000 method which widely uses. This research targets: prediction of strength by weight increase, investigation of the dimensional stabilization effects by measuring the rate of shrinkage change, condition of drug penetration and change of wood texture by using a scanning electron microscope. As the results, the PEG4000 method needs a phased approach over 80% impregnation. On the other hand, the S A method remains steady from over 40% impregnation. The Deformation of carbonized wooden objects used in this experiment is considered as the phenomenon by shrinkage of non-carbonized parts. The PEG4000 method is verified the shrinkage in the samples treated with 20%, 40% and 60%; the S A method is verified the shrinkage in the samples treated with 20%.

• Journal of the Korean Wood Science and Technology
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• v.28 no.2
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• pp.57-65
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• 2000

Objective of research is obtain fundamental data of carbonized wood wastes for soil condition, de-ordorization, absorption of water, carrier for microbial activity, and purifying agent for water quality of river. The carbonization technique and the properties of carbonized wood wastes(wood-based materials) were analyzed. Proximate analysis showed the wood-based materials contains 0.37~2.27% ash, 70~74% volatile matter, and 17~20% fixed carbon. As carbonization temperature was increased, the charcoal yield was decreased. However, no difference in charcoal yield was found due to time increase. The specific gravity after the carbonization decreased about 30~40% comparing to green wood. The charcoal had 1.08~4.18% ash, 5.88~13.79% volatile matter, and 80.15~90.94% fixed carbon. The pH of plywood and particleboard(pH 9 at $400^{\circ}C$, pH 10 at $600^{\circ}C$ and $800^{\circ}C$) made charcoals was higher than that of fiberboard. The water-retention capacity was not affected by the carbonization temperature and time. The water-retention capacity within 24h was about 2~2.5 times of sample weight, and the Equilibrium moisture content(EMC) became 2~10% after 24h. EMC of charcoal from the thinned trees were 9.40~11.82%($20^{\circ}C$, RH 90%), 6.87~7.61%($20^{\circ}C$, RH 65%), and 1.69~2.81%($20^{\circ}C$, RH 25%). EMC of charcoal from the wood-based materials under $20^{\circ}C$, relative humidity(RH) 90% was similar to EMC of charcoal from the thinned trees(9~11 %). However, under $20^{\circ}C$, RH 25.65%, EMC of charcoal from the wood-based materials were higher(2~3%) than EMC of charcoal from the thinned trees. Every charcoal from the wood-based materials fulfilled the criteria in JWWA K 113-1947.

• Journal of the Korean Wood Science and Technology
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• v.44 no.5
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• pp.785-808
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• 2016

The objective of this study was to investigate the effect of the short-term weathering on the flame retardant performance of wood coated with Dancheong. Flame retardants were applied on the Dancheong coated Korean red pine. Flame retardants applied panels were layed at the two conditions of outdoor exposure and artificial aging to assess the reliability of artificial aging. Flame retardants used were commercial products developed for historical wooden buildings. Scanning electron micrographs revealed the forming of carbonized membrane by melting of flame retardant on wood surface. These carbonized membranes may help delay the further combustion of wood. Flame retardant performance was assessed by measuring heat release rate (HRR) and total heat release (THR) by cone calorimetry. There was no difference in flame retardant performance between before and after 6-month outdoor exposure tests. And also no difference in flame retardant performance between before and after 2-week artificial aging which corresponds to 6-month outdoor exposure. Both tests showed the similar results of combustion characteristics.

• Journal of the Korean Wood Science and Technology
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• v.36 no.4
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• pp.84-92
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• 2008

Anatomical and physical characteristics of Pinus densiflora woods damaged by forest fire at Yangyang-gun, Kangwon-do were investigated in present study. Even though the bark was severly carbonized, no trace of carbonization in the xylem was found. The amount of resin exudation was different by the degree of fire damage. Green moisture content of sapwood in the damaged wood was lower than that in the sound wood, but vice versa in the heartwood. Green density of heartwood in the damaged wood was higher than that in the sound wood, but there was no significant difference in sapwood. Cambial activities were found stopped in the severely damaged wood but were identified in the lightly damaged wood. In safranine staining process, epithelial and ray parenchyma cell walls in the damaged woods showed darker hue than those in the sound wood. Granular substances were observed in the lumina of ray parenchyma and epithelial cells of the severely damaged wood. Relative crystallinity of the outermost growth ring in the severely damaged wood was slightly higher than that in the sound wood.

• Journal of the Korean Wood Science and Technology
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• v.34 no.6
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• pp.21-28
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• 2006

This study was carried out to examine the effect of soil improvement according to the shape of charcoal and the kind of carbonized tree species. As the results, all of the seedlings of Thuja occidentalis and Aesculus turbinata grew better in the charcoal-treated soil than the non-treated soil. In case of powder charcoal, Thuja occidentalis seedlings grew up best in the soil treated with powder charcoal of Pinus koraiensis and then grew well in order of Larix leptolepis > particle board > Quercus acutissima. In case of granulated charcoal, the seedlings grew well in order of the granulated charcoal of Larix leptolepis > particle board > Pinus koraiensis. It was analyzed that the soil porosity and the organic matter content were mo re in the charcoal -treated soil than the non-treated soil also. It is inferred that because the aeration property and the absorption of organic matter were increased in the root zone, the growth of seedlings was better in the char-coal-treated soil.

• Journal of the Korean Wood Science and Technology
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• v.30 no.4
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• pp.33-40
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• 2002

This research was to investigate the adsorption characteristics of charcoals of major Korean wood species (thinned trees) and wood-based materials. As carbonization time and temperature increased, methylene-blue adsorption (MBA) of charcoals of thinned trees and wood-based materials increased. Pinus koraiensis charcoal showed the highest MBA. MBA of softwoods was higher than that of hardwoods. There was a negative correlation between air-dried specific gravity before carbonization and MBA of carbonized thinned trees. The MBA of wood-based materials showed similar value, but wood-based materials in MBA was lower than thinned woods. Surface area and total pore volume of thinned trees and wood-based materials increased as carbonization temperature increased. The species showing highest MBA appeared to have the highest surface area at the carbonization temperature of 600℃ as well. There was a positive correlation between surface area, total pore volume and MBA of charcoals. The charcoal of wood-based materials generally exhibited micro pores.

• Journal of the Korean Wood Science and Technology
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• v.49 no.4
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• pp.360-370
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• 2021

For the purpose of finding new uses for Miscanthus sinensis var. purpurascens, this study first constructed boards with the particles of the plant and impregnated them with phenolic resin at resin impregnation rates of 30 ± 2%, 40 ± 2%, 50 ± 2%, and 60 ± 2%. The impregnated boards were then carbonized at the carbonization temperature of 800℃, after which their density and mechanical properties were examined according to the different resin impregnation rates. The results showed that density, flexural strength performance, Brinell hardness, and compressive strength increased as the resin impregnation rate increased, thus affecting the physical and mechanical properties of the ceramics made of M. sinensis var. purpurascens particles.

• Journal of the Korean Wood Science and Technology
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• v.31 no.6
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• pp.83-88
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• 2003

The woodceramics are porous amorphous carbon and glassy carbon composite materials. Woodceramics attracted a lot of attention in recent years because they are environmentally friendly and because of their unique functional characteristics such as catalysis, moisture absorption, deodorization, purification, carrier for microbial activity, specific stiffness, corrosion and friction resistance, and their electromagnetic shielding capacity. In this paper, we made new products of clay-woodceramics to investigate the industrial analysis and ethylene gas adsorption for basic data of building- and packging- materials keeping fruit fresh for a long time. Clay-woodceramics were carbonized for 3 h of heating in a special furnace under a gas flow of nitrogen(15 ml/min.) from 3 layers-clay-woodparticleboard made from pallet waste wood, phenol- formaldehyde resin(hereafter PF, Non volatile content:52%, resin content 30%), and clay(10%, 20% and 30%). Carbonization temperature was 400℃, 600℃ and 800℃. Experimental results shows that the higher the carbonization temperature, the higher the fixed carbon and the lower the volatile contents. The higher the clay content, the more the ash content. The higher the carbonization temperature, the more the ethylene gas adsorption. Carbonization temperature of 800℃ gave the best reslts as same as that of white charcoal and activated carbon.(800℃-clay-woodceramic: 5.36 ppm, white charcoal: 5.66 ppm, activated carbon: 5.79 ppm) The clay contents did not make difference of ethylene gas adsoption.

• Journal of the Korean Wood Science and Technology
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• v.20 no.2
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• pp.31-42
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• 1992

In this study, the relative effectiveness of antimony trioxide-containing coat on fire retardancy of plywood, particleboard and medium density fiberboard was investigated and compared through ISO ignition test and inclined panel test with non-coated ones. The results obtained were summarized as fallows: Any treated materials was not ignited in inclined panel test with 5 minutes, but only particleboard among treated ones burned in ISO ignition test with fairly delayed time. The weight loss rate of plywood decreased with the increased addition level of fire-retardant and the least values were obtained in particleboard and MDF at addition level of 7% and 5% respectively. Carbonized area of wood based materials decreased with the increased addition level of fire retardant. The temperatures of back in plywood, particleboard treated with fire-retard ant coat containing 7% $Sb_2O_3$ showed the lowest but MDF did not show any effectiveness with the increased addition level. The first flash time of plywood treated with fire retardant coat containing 9% $Sb_2O_3$, MDF and particleboard treated with fire retardant coat containing 7% $Sb_2O_3$ were 257sec., 286.4sec., 165.4sec. respectively.