• 펄프종이기술
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• 제33권3호
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• pp.75-83
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• 2001

The potential of oxygen delignification is a powerful tool to reduce detrimental environmental effects. This study was performed to investigate the effect of steam explosion treatment of chemically treated oak wood on oxygen-alkali pulping. Pulp yield during steam explosion treatment by ${Na_2}{O_3}$-NaOH impregnation was higher than the other impregnation chemicals. Also, NaOH extraction at room temperature after steam explosion treatment improved the kappa number from 140~116 to 90~64. Oxygen-alkali pulping of chemical steam explosion treated woods affected to pulp yields. ${Na_2}{O_3}$-NaOH impregnation was very effective to higher carbohydrate yields at same delignification level. Its carbohydrate yield seemed to be highly related to the effluent pH. Oxygen-alkali pulping after steam explosion treatment of ${Na_2}{O_3}$-NaOH impregnated wood was shown that carbohydrate yield was very high because its effluent pH was increase from natural to mild alkali. Even if oxygen bleaching limit the delignification to 50% in order to avoid unacceptable yield and viscosity losses, oxygen-alkali pulping after steam explosion by ${Na_2}{O_3}$-NaOH impregnation was possible to extend the delignification more than 80%. Considering high pulp yield with lower lignin content from steam explosion treated wood, it might be profitable to end the cook at a high kappa number instead of a low kappa number, and continuously apply the oxygen delignification, in order to better quality pulp.

• Journal of the Korean Wood Science and Technology
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• 제25권4호
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• pp.68-74
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• 1997

This research was studied dissolving pulp for rayon production, which is not KP, SP methods but steam explosion and oxygen alkali treatment. The variation of characterization in wood cellulose after steam explosion and oxygen alkali treatment this follows. In the oxygen alkali treatment of exploded pine wood, yield of dissolving pulp was lower than steam-exploded oak wood, and we have obtained dissolving pulp that high purity cellulose, but degree of polymerization was inclined to decrease less than 200. In the case of steam-exploded oak wood, degree of polymerization was higher than steam-exploded pine wood but purity of cellulose was lower than its.

• Biotechnology and Bioprocess Engineering:BBE
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• 제8권3호
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• pp.205-209
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• 2003

Solubilization of domestic household waste through Steam explosion with Subsequent ethanol production by the microbial saccharifitation and fermentation of the exploded product was studied. The effects of steam explosion on the changes of the density, viscosity, pH, and amounts of extractive components in artificial household waste were determined. The composition of artificial waste used was similar to leftover waste discharged from a typical home in Japan. Consecutive microbial saccharification and fermentation, and simultaneous microbial saccharification and fermentation of the Steam-exploded product were attempted using Aspergillus awamori, Trichoderma viride, and Saccharomyces cerevisiae; the ethanol yields of each process were compared. The highest ethanol yield was obtained with simultaneous microbial saccharification and fermentation of exploded product at a steam pressure of 2 MPa and a steaming time of 3 min.

• Journal of the Korean Wood Science and Technology
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• 제20권3호
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• pp.11-20
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• 1992

Steam explosion is one of the most effective pretreatment for fractionating wood. This leads to the total utilization of wood basic components; cellulose, hemicellulose and lignin. The amount of sugar and lignin extracted with the hot water method was very low. The lignin content of residues after extraction with using a sodium hydroxide treatment, increased delignification of carbohydrate as the concentration of alkali was increased. Oak, pretreated with steam exploded at 25kg/$cm^2$ for 6 min. then 1% alkali for 2hrs. showed a delignification rate up to 95%. A sodium chlorite treatment of steam exploded pine and oak also afforded a high deligninfication effect. Pine, treated 10% sodium chlorite for 2hrs. showed high delignification. However, by using a sodium hydroxide treatment, a 2% retreatment for Ihr. after a 2% for 2hrs. afforded remarkable delignification effect on exploded wood at 30kg/$cm^2$ for 9min. and at 35kg/$cm^2$ for 3-6min. In oak, an initial 2hrs. treatment of 2% sodium chlorite was followed by a second 2hrs. treatment at 10%. This showed a delignification rate of 96%.

• Biotechnology and Bioprocess Engineering:BBE
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• 제8권3호
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• pp.179-182
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• 2003

Anaerobic fermentation was attempted to produce methane from the wood chip (Eucalyptus globulus). By the pretreatment of the wood chip using hot water with high temperature, NaOH, and steam explosion, the production of methane gas was enhanced. The pretreatment using Steam explosion resulted in more amount of methane gas produced than the treatment using either hot water or 1% (w/w) NaOH with high temperature, and the steam explosion at a steam pressure of 25 atm and a steaming time of 3 min was the most effective for the methane production. The amount of methane gas produced depended on the ratio of weight of Klason lignin, a high molecular weight lignin, in the treated wood chip.

• Journal of the Korean Wood Science and Technology
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• 제47권2호
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• pp.189-199
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• 2019

This study addresses the biorefinery feedstock from Pinus densiflora. This raw material is a major tree species in the Republic of Korea; it is renewable, has cost-effective, and is readily available. In this study, steam explosion of P. densiflora was performed in a reactor at $225^{\circ}C$ and with 1 to 13 min reaction times with or without previous water impregnation. The combined severity factor (Ro), which is an expression relating the reaction temperature and reaction time used in the steam explosion treatment, ranged from 3.68 to 4.79. The influence of both impregnation and steam explosion conditions were investigated by examining color variations, chemical composition, and mass balance on the pretreated solids. The results showed that steam-exploded P. densiflora that was not impregnated with water exhibited significantly darker color (chroma 28.8-41.4) than water-impregnated and steam-exploded P. densiflora (chroma 18.8-37.3). The increased ${\alpha}$-cellulose and lignin contents were detected as the severity factor increased. Furthermore, the ${\alpha}$-cellulose and lignin contents in the non-impregnated/steam-exploded P. densiflora were higher than those in the water-impregnated/steam-exploded P. densiflora. However, the decreased holocellulose content was detected as the severity factor increased. In mass balance, the holocellulose yield from water-impregnated/steam-exploded P. densiflora was higher than that from the non-impregnated P. densiflora.

• Journal of the Korean Wood Science and Technology
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• 제18권4호
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• pp.18-25
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• 1990

As polysaccharides in lignocellulosic materials are encrusted with aromatic lignin molecules and have high crystallinity, these require pretreatment to improve their digestability by cellulolytic enzymes. Though a number of pretreatment methods have been proposed, the steam explosion process is evaluated as a promising method. This study was performed to investigate the effect of delignification treatment by alkali, methanol and the others on the enzymatic hydrolysis. Delignification treatment resulted in great increase rate in enzymatic hydrolysis. Concerning to the effect of delignication reagents on the enzymatic hydrolysis, methanol treatment was more effective than alkali in the case of oak wood. In pine wood, the delignification did not showed any significant enhancement of hydrolysis rate. Complete delignification by Alkali-Oxygen. Alkali treatment showed high saccharification rate of 99.5%.

• 한국환경농학회지
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• 제17권4호
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• pp.324-328
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• 1998

볏짚과 보리짚을 효율적으로 퇴비화하기 위하여 이들을 폭쇄처리하여 퇴비화 하였다. 볏짚과 보리짚을 폭쇄 처리하였을 때 유기산의 생성으로 원시료에 비해 pH가 각각 4.0, 3.7로서 낮아졌고, EC도 1.66, 3.19mS/m로 감소하였으며, cellulose, lignin 및 총 탄소 함량은 증가되었다. 퇴적 16주 후에 볏짚이나 볏짚폭쇄물에서는 총질소가 $2{\sim}2.5$%가 더 증가한 것으로 나타났으나, 보리짚은 폭쇄를 하면 1.7%가 증가하지만 폭쇄처리를 하지 않은 시료는 오히려 0.41% 감소하였다. 이런 결과로 보리짚은 퇴비화가 어려운 재료이지만 폭쇄처리를 하면 퇴비화가 용이해짐을 알 수 있다. 볏짚의 C/N비는 퇴비화 초기부터 급격히 감소하였지만, 폭쇄처리를 한 볏짚과 보리짚은 퇴비화 후기에 급격히 감소하였다. 이것은 폭쇄처리로 유기산이 생성되어 초기에는 낮은 pH때문에 미생물이 생육이 어려웠으나, 퇴비화가 진행됨에 따라 안정하게 되어 퇴비화가 더 잘 이루어진다는 것을 알 수 있었다. 따라서 재료를 폭쇄처리하면 공극량이 증가하는 동시에 유효 표면적이 증가하여 퇴비화 기간을 단축할 수 있으며, 고온, 고압의 수증기에 의해 병원성균 및 잡초 종자가 제거된다. 이는 폭쇄처리에 의해 퇴비화가 효율적으로 진행된다는 것을 시사한다.

• Journal of the Korean Wood Science and Technology
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• 제23권1호
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• pp.54-60
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• 1995

This paper reports on the changes of equilibrium moisture contents and specific surface areas of Poplar wood(Populus euramericana) for various steam explosion treatments. Equilibrium moisture contents(EMC) and specific surfaces of steam exploded woods were measured under the moisture adsorption course at 25$^{\circ}C$, and compared with those of other materials and wood meals. The EMCs of steam exploded wood meal were 1~5% less in comparison with that of wood meal. In the case of delignified steam exploded wood meal and delignified wood meal, the same tendency was appeared too. But absolute values of EMCs for delignified wood meals were larger than those of the wood meal. For the changes of EMC by the steam exploded conditions, the EMC decreased with the increase of the steam explosion pressure. On the other hand, specific surface areas were calculated from BET plots based on amounts of monomolecular vapor adsorption of various wood meals. Specific surface areas of the wood meal and delignified wood meal were 90~145, 34~90($m^2/g$) respectively, and which were greater in comparison with those of steam exploded wood meals and delignified steam exploded wood meals. From these results, it is considered that the amount of water vapor adsorption was decreased by the increase of the crystallinity, effect of heat treatment, and coating by melted lignin in during the steam explosion.

• Journal of the Korean Wood Science and Technology
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• 제25권3호
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• pp.37-42
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• 1997

This study was carried out to track the heated-air flows within the tree disk through measuring the distribution of wood temperatures during explosing the 7.5mm-thick Japanese cedar disk and to investigate the effects of the time for the first explosion cycle and the number of explosion cycles on the improvement of permeability of tree disk. If the tree disk are explosed when the temperatures of the shell and core of it are not equilibrium yet, all of the inflated airs in the shell after explosion don't flow out toward the autoclave and some of them flow into the core of which the air pressures are lower than those of the shell. It is very effective for the improvement of permeability of tree disk to make the first explosion cycle when the temperatures of the shell and the core equilibrate at the setting temperature of steam in the autoclave. The more tree disks were explosed under the same conditions of first explosion, the more their permeabilities were improved.