국내산 잣나무와 낙엽송의 재질

권성민,황원중,권구중,김남훈 江原大學校 森林科學硏究所 2004 Journal of Forest Science Vol.20 No.-

국산 잣나무와 낙엽송의 비중, 연륜폭, 만재율, 종압축강도, 횡압축강도 및 전단강도를 측정하고 방사 ?향의 병이를 조사하여 다음의 결과를 얻었다. 1) 비중은 잣나무가 0.48로 낙엽송의 0.88보다 약 2배정도 낮은 값을 보였다. 두 수종 모두 수심에서 낮은 값을 보여주고 그 후 약 15연륜 까지 다소 증가하다가 일정해지는 경향을 보여주었다. 2) 연륜폭은 잣나무 3.43㎜, 낙엽송 2.83㎜로 잣나무가 낙엽송에 비해 넓었으며, 만재율은 잣나무 30%, 낙엽송 47%로 낙엽송이 잣나무에 비해 높았다. 두 수종 모두 만재율이 커짐에 따라 비중은 커지는 경향을 나타냈다. 3) 종압축강도와 종압축 비례한도, 종압축 영계수는 잣나무가 각각 300kgf/㎠, 270kgf/㎠, 9.2×10³kgf/㎠로서 낙엽송의 600kgf/㎠, 550kgf/㎠, 20×10³kgf/㎠에 비해 모두 낮은 수치를 나타내었다. 종압축강도, 종압축 비례한도 및 영계수의 방사방향변이는 두 수종 모두 뚜렷한 경향을 보이지 않았다. 4) 방사단면의 전단강도는 잣나무가 51kgf/㎠, 낙엽송이 69kgf/㎠으로 낙엽송이 컸으며, 접선단면은 잣나무가 56kgf/㎠, 낙엽송이 86kgf/㎠으로 낙엽송이 큰 값을 나타내었다. Density, annual ring width, latewood percentage and compressive properties of Pinus koraiensis and Larix kaempferi grown in Research Forest of Kangwon National University were measured and their radial variations were investigated. Density(Wa/Va) of Pinus koraiensis and Larix kaempferi was 0.48g/cm² and 0.88g/cm², respectively. Density of both species was slightly lower at pith area, increased gradually with cambial age up to about 15 years and then became constant. Annual ring width of both species was 3.43㎜ and 2.83㎜, respectively. Annual ring width of both species was irregular at pith area but regular after about 20 years. Latewood percentage of both species was 30% and 47%, respectively. Latewood percentage of Pinus koraiensis and Larix kaempferi increased with cambial age up to 14 years and 10 years, respectively and then became constant. Compressive strength, proportional limit and Young's modulus parallel to the grain of Pinus koraiensis were 330 kgf/cm², 270 kgf/cm² and 9.2×10³ kgf/cm², and those of Larix kaempferi were 600 kgf/cm², 550 kgf/cm² and 20×10³ kgf/cm², respectively. Shearing strength in radial direction of Pinus koraiensis and Larix kaempferi was 51 kgf/cm² and 69 kgf/cm², and that of tangential direction was 56 kgf/cm² and 86 kgf/cm², respectively. In this study, compressive and shearing properties of both species did not show any significant differences between juvenile wood and adult wood. Both species showed significant differences in the measured values.

산불 피해 소나무재의 역학적 특성 및 급속오븐 건조특성

황원중,권구중,박종수,김남훈 한국목재공학회 2003 목재공학 Vol.31 No.4

본 연구에서는 산불 피해 소나무재의 이용을 위한 기초자료를 얻고자 역학적 및 건조 특성을 조사하였다. 산불피해재는 종압축 특성, 전단강도, 충격휨흡수에너지 등에서 건전재와 거의 유사한 결과를 보여주었으며, 산불피해재 변재부의 휨특성은 건전재보다 양호하게 나타났다. 건전재와 산불피해재 변재부의 생재함수율은 산불피해재가 다소 낮았으나, 건조속도는 거의 차이가 없었다. 건조시 발생되는 초기할렬은 건전재가 산불피해재보다 발생율이 높았고, 내부할렬은 건전재와 산불피해재에서 발생되지 않았다. 따라서 산불에 의해 피해를 입은 목재의 대부분은 수피부를 제거하여 이용할 경우 건전재와 거의 동일한 용도로서 사용이 가능할 것으로 생각된다. The Mechanical and drying characteristics of Pinus densiflora wood, which was damaged by forest fire, and sound wood were examined. There were no significant differences in axial compressive properties, shearing strength and impact bending absorbed energy between damaged and sound woods. But the bending properties of damaged wood were slightly higher than those of sound wood. The green moisture content of sapwood in damaged wood was lower than that in sound wood, but oven-drying rate was similar in both woods. Number of initial check in damaged wood was smaller than that in sound wood, and inner check in damaged and sound woods was not observed. Consequently, it is considered that mostly damaged wood by forest fire can be used for wood material after removing the considered that mostly damaged wood by forest fire can be used for wood material after removing the bark.

Pyrolysis of cellulose by CO2 Laser

( Gu Joong Kwon ),( Masahisa Wada ),( Shigenori Kuga ),( Keko Hori ),( Mitsuyoshi Yatagai ),( Keisuke Ando ),( Nobuaki Hattori ) 韓國木材工學會 2004 한국목재공학회 학술발표논문집 Vol.2004 No.-

Characteristics of White Charcoal Produced from the Charcoal Kiln for Thermotherapy(온열욕 겸용 숯가마에서 생산된 백탄의 특성)

( Gu Joong Kwon ),( Ah Ran Kim ),( Hee Soo Lee ),( Seung Hwan Lee ),( Wahyu Hidayat ),( Fauzi Febrianto ),( Nam Hun Kim ) 한국목재공학회 2018 목재공학 Vol.46 No.5

본 연구에서는 온열욕 겸용을 위해 제작한 숯가마와 전통식 숯가마에서 제조한 백탄의 특성에 대해서 비교, 검토하였다. 온열욕 겸용 숯가마는 밀폐된 숯가마에서 발생하는 미세먼지 및 유해가스와 같은 환경문제를 최소화하고 편안함과 안전성을 고려하여 제작하였다. 온열욕 겸용 숯가마에서 제조한 백탄은 전통식 숯가마의 백탄보다 회분과 휘발분이 다소 높았고 고정탄소가 다소 낮았다. 온열욕 겸용 숯가마에서 생산된 백탄의 밀도는 기존의 전통식 숯가마 백탄보다 약간 높았지만, 평형함수율과 pH는 거의 차이가 없었다. 발열량, 정련도, 경도와 해부학적 구조는 숯가마에 따른 차이가 없었다. 결론적으로 온열욕 겸용을 위해 개량된 숯가마에서 제조한 백탄은 국립산림과학원의 품질인증기준을 충족하였고, 온열욕 겸용 숯가마는 목탄제조에도 적합한 것으로 판단되었다. In this study, the characteristics of the white charcoal from charcoal kilns made for both charcoal production and thermotherapy and from the traditional charcoal kiln were compared and examined. A charcoal kiln for thermotherapy as a secondary purpose was made to minimize environmental problems such as fine dust and harmful gas generated from sealed charcoal kiln in consideration of comfort and safety. White Charcoal produced from the charcoal kiln for both charcoal production and thermotherapy had higher ash and volatile matter and lower fixed carbon than that from the traditional charcoal kiln. The density of the white charcoal produced from the charcoal kiln for both charcoal production and thermotherapy was slightly higher than that of the traditional one, but the equilibrium moisture content and pH were not significantly different. The calorific value, refinement degree, hardness and anatomical structure were not different between the two. It was concluded that the white charcoal produced from the advanced charcoal kiln for thermotherapy as a secondary purpose meets the quality certification standards of Korea Forest Research Institute.

Structural properties and adsorption capacity of holocellulose aerogels synthesized from an alkali hydroxide-urea solution

Kwon, Gu-Joong,Kim, Dae-Young,Hwang, Jae-Hyun,Kang, Joo-Hyon Korean Physical Society 2014 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.64 No.10

A tulip tree was used to synthesize a holocellulose aerogel from an aqueous alkali hydroxide-urea solution with the substitution of an organic solvent followed by freeze-drying. For comparison, the synthesized holocellulose aerogels were divided into two groups according to the source of the hydrogel, an upper suspended layer and a bottom concentrated layer of the centrifuged solution of cellulose and NaOH/urea solvents. We investigated the effects of the temperature of the pre-cooled NaOH/urea solution (i.e., dissolution temperature) on the pore structure and the adsorption capacity of the holocellulose aerogel. A nano-fibrillar network structure of the holocellulose aerogel was observed, with little morphological difference in pore structure for different dissolution temperatures. Both micropores and mesopores were observed in the holocellulose aerogel. The specific surface area of the holocellulose aerogel was generally greater at lower dissolution temperatures. In a series of adsorption tests using methylene blue, the holocellulose aerogel showed the greatest adsorption capacity at the lowest dissolution temperature tested (-2A degrees C). However, the dissolution temperature generally had little effect on the adsorption capacity. The holocellulose aerogel produced from the upper suspended layer of the centrifuged hydrogel solution showed a greater porosity and adsorption capacity than the one produced from the bottom concentrated layer. Overall, the aerogel made by utilizing a delignified tulip tree display a high surface area and a high adsorption property, indicating its possible application in eco-friendly adsorption materials.

Tailoring the characteristics of carbonized wood charcoal by using different heating rates

Kwon, Gu-Joong,Kim, Dae-Young,Oh, Choong-Hyeon,Park, Byung-Ho,Kang, Joo-Hyon Korean Physical Society 2014 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.64 No.10

This study examined the characteristics of charcoals generated from White Lauan (Pentacmecontorta) and Punah (Tetrameristaglabra) by using different carbonization temperatures and heating rates. The scanning electron micrographs showed vestured pits in the White Lauan and raphide crystals in Punah as their respective anatomical characteristics. A slower heating rate resulted in a lower temperature to obtain the same amount of weight loss, regardless of the species being tested. A greater charcoal yield was obtained at a higher heating rate. The specific surface area was smaller in the charcoal produced at a higher carbonization temperature, but the heating rate had little effected. For both wood species, the axial compressive strength of the charcoal increased as the carbonization temperature was increased. The X-ray diffractograms of White Lauan and Punah woods heated at 1200A degrees C indicated thermal decomposition of the crystal structure of cellulose, but no appreciable structural changes occurred under the tested heating rate conditions. Overall, the heating rate affected the charcoal yield but not the specific surface area, compressive strength, and crystal structure.

숙련공에 의한 목탄제조과정 중 전통식 탄화로 내의 온도변화 (Ⅰ)

권구중(Gu-Joong Kwon),박형수(Hyung-Soo Park),이성재(Sung-Jae Lee),권성민(Sung-Min Kwon),이귀현(Gwi-Hyun Lee),김남훈(Nam-Hun Kim) 한국산림바이오에너지학회 2008 산림바이오에너지 Vol.27 No.1

숙련자에 의한 목탄제조과정 중 전통식 탄화로내의 온도변화와 목탄의 수율을 조사하였다. 온도 측정에는 플라티늄을 원료로한 R형의 열전지와 니켈을 원료로한 K형의 열전지를 이용하였다. R형의 온도측정범위는 0∼1600℃, K형은 0∼1200℃로 탄화로 내부는 R형을, 굴뚝부위는 K형을 사용하여 온도를 측정하였다. 탄화과정은 5일에서 6일 정도가 소요되었다. 탄재의 착화시 탄화로 내부의 온도는 약 700∼800℃였고 연통부위 온도는 약 80∼90℃였다. 목초액을 얻는 동안의 탄화로 내부온도는 약 600℃였고 굴뚝부위는 약 80∼90℃였다. 정련단계에 이르기까지 탄화로 내부온도는 증가하여 정련단계에서는 900∼1100℃의 고온에 달하였다. 정련단계에서 굴뚝의 온도도 크게 올라 약 600℃에 달하였다. 목탄의 수율은 9.8∼12.3%였다. 본 연구에서 전통식 탄화로를 이용한 숙련자의 목탄제조 과정 중의 온도변화 경과곡선과 목탄의 수율이 밝혀졌다. 얻어진 온도변화 경과곡선은 초심자의 제탄과정에서 지표의 하나로 이용될 수 있을 것이다. This study was performed to investigate the variation of temperature in a Korean traditional kiln controlled by an expert during carbonization process of wood. The yield of charcoal was also investigated. Two kinds of thermocouples, R-type and K-type, were used for measuring temperatures. Temperature tolerance of the R-type thermocouple prepared from platinum was from 0℃ to 1600oC and that of K-type thermocouple prepared from Nickel was from 0℃ to 1200℃. R-type was used for measuring temperature in the kiln while the K-type for measuring temperature in chimney. In this traditional kiln system, carbonization process was completed in five to six days. In the kiln, the ignition temperature was ranged from 700℃ to 800℃. During gathering wood vinegar, the temperature was kept around 600℃. And then the temperature were increased gradually prior to be refined. Finally, the temperature in refining process was reached to maximum point, 1000±10℃. In the chimney, the temperature was increased gradually from ca. 80℃ at ignition to ca. 600℃ at refining. The yield of wood charcoal was 9.8 to 12.3%. In this study, we showed the temperature profile through carbonization process in the traditional kiln and the yield of wood charcoal. The temperature profile can be used for beginner during carbonization process as a guideline.

목타르와 톱밥을 혼합하여 제조한 펠릿의 특성

권구중 ( Gu Joong Kwon ),권성민 ( Sung Min Kwon ),차두송 ( Du Song Cha ),김남훈 ( Nam Hun Kim ) 한국목재공학회 2010 목재공학 Vol.38 No.1

LiOH/Urea 수용액을 이용하여 제조한 재생 셀룰로오스 겔의 공극분포 및 중금속 흡착 특성

권구중(Gu-Joong Kwon),양지욱(Ji-Wook Yang),황교정(Kyo-Jung Hwang),황재현(Jae-Hyun Hwang),황원중(Won-Jung Hwang),김대영(Dae-Young Kim) 한국펄프·종이공학회 2016 펄프.종이기술 Vol.48 No.4

This experiment was carried out to study the pore distribution of regenerated cellulose gel (RCG) prepared by using a LiOH/urea solution and the adsorption characteristics of a lead and cadmium. The specific surface area of RCG was higher in the 2% cellulose concentration with a higher number of beads type than the film type. In the case of pore distribution, they were between 50-150 nm of film type RCG. However, large pore, which are more than 150 nm also existed on the beads type RCG. The adsorption characteristics of cadmium and a lead showed the removal efficiency of the beads type RCG was superior to the film type RCG. The heavy metal removal, based on a pH value of 5-6, showed slightly higher efficiency. Moreover, the rate of removal of lead appeared highly comparable with that of cadmium. According of the FT-IR spectrum analysis, heavy metal adsorption of RCG appeared to be due to the absorption of heavy metals by the hydroxyl group within the cellulose.

개량형탄화로를 이용한 제탄과정 중 탄화로 내,외벽 온도변화 및 목탄 특성

권구중 ( Gu Joong Kwon ),권성민 ( Sung Min Kwon ),장재혁 ( Jae Hyuk Jang ),황원중 ( Won Joung Hwang ),김남훈 ( Nam Hun Kim ) 한국목재공학회 2011 목재공학 Vol.39 No.3

본 연구는 개량형 탄화로를 이용하여 제탄과정 중 탄화로 내 · 외벽체의 온도변화를 측정하고. 제탄된 목탄의 특성을 조사하였다. 공시탄화로의 탄화과정은 8일정도 소요되었다. 탄재탄화시 탄화로 내부온도는 720℃ 정도였고. 정련단계에 이르기까지 탄화로 내부온도는 점점 증가하여 정련단계에서는 l. 000℃ 이상의 고온에 달하였다. 연통부는 착화시 90℃였고. 서서히 증가되어 정련단계에서는750℃까지 상승하였다. 이 때 탄화로 벽체의 온도변화는 제탄과정 중의 탄화로 내부의 온도변화 경과곡선과 비슷한 경향을 보여주었다. 제탄과정에서 나타난 탄화로 벽체의 최고 온도는 500℃ 정도였다. 적외선 열화상카메라를 이용하여 체탄전 탄화로의 내 · 외벽체의 온도분포를 측정한 결과, 출탄 후 시간이 다소 경과되어도 상당한 양의 잠열이 탄화로 벽체와 천장에서 감지 되었다. 출탄된 목탄의 고정탄소은 85.9∼89,9% 였다, 점련도는 1, 경도는 12, 발열량은 7.047~7.456 kcal/kg. pH는 9.0∼9.9였다. 목탄의 수탄율은 13.8% 정도로 가존의 탄화로에 얻어진 수탄을 9.8∼12.3%에 비해 1.5% 정도 향상되었다. The study was performed to investigate the characteristics of charcoal and temperature change of a kiln`s inner and outer walls in carbonization process using improved kiln. In this kiln system, carbonization process was completed in eight days In the kiln, the ignition temperature was kept about 720°C And then the temperature were increased gradually prior to be refined. Finally, the temperature in refining process was reached to maximum point, 1,000°C In the chimney, the temperature was increased gradually from 90°C at ignition to 750°C at refining. The temperature change of the kiln wall resembles a temperature change progress curve during a carbonization process The highest temperature of the kiln wall that appeared hy a carbonization process was around 500°C As a result of having measured an inner wall and the outer wall of the kiln using an infrared thermography camera, it was judged with there being considerable latent heat on kiln wall and ceiling. Fixed carbon contented of charcoal was 85.9~89.9%. Refining degree of charcoal, hardness, calorific value and pH were I, 12, 7,047- 7,456 kcal/kg, 9.0~9.9, respectively. The yield of wood charcoal was 138% and compared to conventional kiln`s yield increased 1.5%.