• Title/Summary/Keyword: Larix kaemferi Carr

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The Study on the Characteristics of Pellets Manufactured with Morphologically Different Domestic Larix Kaemferi Carr Sawdust (국내산 낙엽송의 톱밥 유형에 따른 펠릿특성에 관한 연구)

  • Ryu, Jae-Yun;Kang, Chan-Young;Lee, Eung-Su;Seo, Jun-Won;Lee, Hyun-Jong;Park, Heon
    • Journal of the Korean Wood Science and Technology
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    • v.38 no.1
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    • pp.49-55
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    • 2010
  • morphologically different Larix Kaemferi Carr sawdust. The pellet characteristics included moisture contents satisfied the first grade (less than 10%) of quality standard of wood pellets announced by Korea Forest Research Institute. Densities were also adequate for the first grade (640kg/$m^3$) on the quality standard and there was no large difference in other characteristics of pellets, however, pellets manufactured with planer shavings had the highest density. Ash contents also passed the first grade (less than 0.7) of quality standard. But bark pellet exceeded the second grade (1.5%) in ash content. Lower absorption ratio of bark pellet showed the effect on hygroscpicity. The heating value of the manufactured wood pellets in this study exceeded the first grade of quality standard(more than 4,300 kcal/kg).

Estimation of thinning period of Larix kaemferi Carr. plantation in the central part of Korea (중부지방 낙엽송 조림지의 간벌 시기 추정)

  • 이종희;김홍은;권기철;정택상
    • Journal of Korea Foresty Energy
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    • v.20 no.2
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    • pp.69-80
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    • 2001
  • Larix kaemferi Carr. is one of main timber species in Korea that could be found in plantations and growing stands on all over the country The proper practice of thinning is one of very important techiques in silviculture, which greatly affects the quality and size of timber produced. Proper thinning period is considered to be important for maintaining stand growth before competition initiated. To investigate suitable thinning period, this study investigates the volume and radial growths of Larix kaemferi plantation in Mt. Worak located in the central part of Korea. The main findings and conclusions obtained from this study were as follow ; (1) The tree height curve equation for Larix kaemferi in Mt. Worak was calculated H=4.25783+0.80024D(H=Tree height, D=DBH). (2) To estimate tree volume for Larix kaemferi by DBH and tree height or only by DBH, regression equations were calculated as V=0.00147-0.002095D-0.000211H+0.00015D.H++$0.000744D^2$+$0.000008H^2$(V=Volume(($m^3$), H=Tree height(m), D=DBH(cm)), V=0.0000794-0.000512D+$0.000826D^2$. (3) The criteria of estimating thinning time of Larix kaemferi are the age when maximum tree height-MAI(mean annual increment) obtained and the age when annual DBH increments of dead trees decrease to below average. (4) The age of maximum tree height MAI was not significantly correlated with stocking. Therefore, it can not be used as a criterion for estimating thinning time of Larix kaemferi (5) The estimated thinning time equation of Larix kaemferi was obtained by regression analysis of the disk section collected from dead trees. The obtained equation is Y=0.2825+0.01752X(Y=Desirable thinning age, X=the sum total of nearest 4-trees interval(cm)). (6) General estimated thinning age of Larix kaemferi, which planted 3,086 stocks/ha, is concluded as 12 to 14 year.

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Physical Properties of Larch(Larix kaemferi Carr.) Treated by High Temperature Steaming - Effect of high temperature steaming on shrinkages of larch block - (고온수증기처리에 의한 낙엽송재의 물성(제2보) - 고온수증기처리에 의한 낙엽송재의 수축율 변화 -)

  • Kim, Jung-Hwan;Lee, Weon-Hee
    • Journal of the Korean Wood Science and Technology
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    • v.30 no.2
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    • pp.102-107
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    • 2002
  • This study deals with a physical properties of Larch(Larix kaemferi Carr.) treated at temperatures above 100℃. Treatment conditions of this experiment were operated at regular intervals of 20℃ at temperature up to 180℃ for 10, 30, 60 and 90 minutes by using the bomb, respectively. The results of this study were as follows : 1) The density was decreased with increasing the times and temperatures of steaming. 2) It was considered that the steaming treated specimen's higher shrinkage compared to control was due to change of composition and structure in cell wall. 3) The warpage of half edge grain specimen was decreased by high temperature steaming.

Physical Properties of Larch(Larix kaemferi Carr.) Treated by High Temperature Steaming (고온수증기 처리에 의한 낙엽송재의 물성변화)

  • Kim, Jung-Hwan;Lee, Weon-Hee
    • Journal of the Korean Wood Science and Technology
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    • v.30 no.4
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    • pp.1-7
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    • 2002
  • This study deals with physical properties of Larch(Larix kaemferi Carr.) treated by steaming at temperatures above 100℃. Treatment conditions of this experiment were operated at regular intervals of 10℃ at temperature up to 130℃ for 10, 30 and 60 minutes by using the auto-clave. The Bending strength and compressive strength along the grain were slightly decreased with increasing the treating temperatures. There was no significant relations between wood strength and steaming temperatures. At the range from 120℃ to 130℃ of steaming temperature, it was considered that the change of composition and structure in cell wall was changed due to release of stresses. Water absorption characteristics were not affected by steaming temperature. In this experiment limits, it was concluded that physical properties of wood by steaming treatment were affected more largely by wood density than by treating temperature.

Flexural properties of dear specimens made from small diameter thinned trees (국산 주요 간벌 소경재의 무결점재에 대한 휨특성)

  • 차재경
    • Journal of Korea Foresty Energy
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    • v.22 no.1
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    • pp.44-48
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    • 2003
  • Flexural properties were investigated on clear specimens made from small diameter thinned trees of pitch pine (Pinus rigida Mill.), Japanese red pine (Pinus densiflora Sieb. et Zucc), Japanese larch (Larix kaempferi Carr.), and sawtooth oak (Quercus acutissima Carr.). MOR and MOE values of small clear specimen were depended on the species. The highest density of sawtooth oak shows the highest values of MOR and MOE. However, the lowest density of Japanese larch shows the lowest values of MOR. It was also shown that flexural properties could be predicted by stress wave MOE, since the correlations between stress wave MOE and flexural properties were relatively good.

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A Study on Productivity and Quality Characteristics of Wood Pellets by Larix Kaemferi Carr Sawdust with Adding Vegetable Oil and Ozonized Vegetable Oil (식물유 및 오존산화 식물유를 첨가한 낙엽송 목재펠릿의 생산성 및 품질특성에 관한 연구)

  • Lee, Eung-Su;Kang, Chan-Young;Seo, Jun-Won;Park, Heon
    • Journal of the Korean Wood Science and Technology
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    • v.39 no.4
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    • pp.359-369
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    • 2011
  • The study was carried out to investigate the quality characteristics of pellets manufactured with adding soybean oil, waste soybean oil, ozonized soybean oil and ozonized waste soybean oil to Larix kaemferi Carr sawdust. The characteristics of pellet included moisture contents, heating value, ash contents, apparent densities, durabilities, absorption ratio and elementary analysis. Moisture contents were shown 7.66~9.48% which satisfied the first grade (less than 10%) of quality standard of wood pellets announced by Korea Forest Research Institute. The heating value of the manufactured wood pellets in this study exceeded the first grade of quality standard (more than 4,300 kcal/kg) and it appeared that the pellets manufactured with adding oils and ozonized oils had more heating value than the control pellets. Ash contents 0.34~0.42% also passed the first grade (less than 0.7%) of quality standard and apparent densities were adequate for the first grade (640 kg/$m^3$) on the quality standard. Durabilities of the pellets manufactured with adding soybean oil and ozonized waste soybean oil were shown over the first grade (97.5 kg/$m^3$) of quality standard. In the general results of durabilities, the pellets manufactured with additives had better values than the control pellets. After 24 hours absorption ratio experiment, absorption ratio of pellets manufactured with additives also appeared much lower moisture absorption than the control pellets and they still had the same results after 5days absorption ratio experiment. Elementary analysis of the sulfur content was satisfied the first grade (less than 0.05%) of quality standard of wood pellets and the nitrogen content was also adequate for the first grade (less than 0.3%) of quality standard of wood pellets.