도시 폐휴지의 질산 펄프제조와 펄프폐액의 입상 비료화 기술개발(I) -폐골판지 상자(OCC)의 질산 펄프제조 조건-

임기표,위승곤,김창래,양정훈 한국펄프종이공학회 2000 펄프.종이기술 Vol.32 No.4

A series of studies on nitric-acid pulping of municipal recycled waste papers were carried out to substitute the bleached chemical pulp imported for producing printing paper as well as to use its solidified spent-liquor as fertilizer. The first experiment was carried out to find the optimum treatment conditions such as pulp consistency, nitric acid charge and temperature in $HNO_3$-alkali pulping process. The results obtained were as follows: 1. Some selective delignification of OCC pulp was conducted by $HNO_3$-alkali process. The higher the temperature and concentration of nitric acid, the lower the pulp yield and kappa number of treated pulp. while its brightness was increased. 2. The higher consistency required the stronger mixing in case of more than 5% pulp. 3. In the laboratory, the suitable $HNO_3$-treating condition seemed to be less than 6% consistency, lower than 500% $HNO_3$charge on pulp and lower than $100^{\circ}C$ in cooking temperature. 4. The spent liquor with 1.77% N-content seemed to be slow-release nitrogen fertilizer suitable for agriculture.

종이의 특성에 영향하는 펄프 섬유특성의 정량적 해석(I)

이강진,박중문 한국펄프종이공학회 1998 펄프.종이기술 Vol.30 No.2

Refining is one of the most important processes of fiber treatment that provides optical and physical properties of final paper products. The evaluation method of refining progress is usually freeness (CSF) or wetness (SR) test because of its rapidity and convenience. However, there are some deficiencies in using freeness or wetness test to evaluate pulp fibers accurately because its results are more influenced by fines contents than extent of fibers treatment. The objective of this study is to show the deficiency of wetness in evaluating the refining process. For this, beating is done by varying the beating load. Handsheets are made after beating until 25 and $32^{\circ}C$ SR, and then paper properties are measured. Refined fibers are analyzed by fiber length, fines contents, curl, kink, WRV, and zero-span tensile strength. The results show that longer beating time is required to reach the same wetness at lower beating load. There are differences in the average fiber length, distribution curve of fiber length, fines contents, curl, kink, WRV of long fiber fraction, drainage time, and zero-span tensile strength of rewetted sample at different beating load. At the low beating load in the same wetness, apparent density, breaking length, burst strength, and tear strength are higher, while opacity and air permeability are lower than those of the high beating load. Using Page s equation, which shows the relationship among tensile strength, intrinsic fiber strength, and interfiber bonding strength, interfiber bonding strength is calculated and analyzed to explain final paper properties. At $25^{\circ}C$ SR, interfiber bonding strength is only slightly higher at 2.5kgf beating load, while the intrinsic fiber strength is substantially higher. At $32^{\circ}C$ SR, intrinsic fiber strength is a little bit higher at 2.5kgf beating load, and interfiber bonding strength is remarkably higher than those of 5.6kgf beating load. These results can be used to explain the different properties of the final paper at selected beating loads.

벼의 종이 멀치재배법 및 멀치용 종이 개발을 위한 연구

신동소,이변우 한국펄프종이공학회 1997 펄프.종이기술 Vol.29 No.1

To establish the weed control method without herbicide and weeding work, mulch paper was developed from domestic old corrugate container. Basis weight of mulch paper should be above 120 g/$m^2$ to guarantee the mechanical properties. It was concluded that polyamide polyamine epichlorohydrin was desirable to improve the wet strength of mulch paper and the optimum addition level was about 1.5% on the basis of oven dry pulp. The mulch paper was found to be effective in controlling paddy weeds. For the complete weed control the mulch paper should be sustained without decomposition over 45 days. As the paper mulching reduced the soil temperature, the mulch paper was required to improve the penetration of radiant heat.

박테리아 셀룰로오스의 첨가가 화학열기계펄프의 종이물성에 미치는 영향

조남석,최태호,서원성 한국펄프종이공학회 1998 펄프.종이기술 Vol.30 No.4

The bacterial cellulose(BC) has many unique properties that are potentially and commercially beneficial. In order to enhance inherently inferior physical property of chemithermomechanical pulp(CTMP) sheet, chemical pulp has been used widely. Bacterial cellulose also has an enhanced sheet strength because of its unique physical and morphological features. This study was carried out to inverstigate the effect of BC addition on physical properties of CTMP sheets. The effect of BC addition on its optical properties was also discussed. The apparent density, internal bond strength, Young's modulus, tensile strength and folding endurance of CTMP sheet are increasing with increase of BC contents. This strength increase would be attributed to the increase of relative bonding sites among pulp fibers by addition of BC which has microfibrillar structure with very high specific surface areas. There were not so significant changes in opacity of CTMP sheet upto 20% addition level of BC, while over 40% addition, the opacity gradually decreased and levelled off. Porosity is decreased with addition of BC. This decrease would be attributed to densification of sheet by fine and filamentous structure of BC fibers.

효소를 이용한 크라프트펄프의 무감소표백(제2보) -소나무 크라프트펄프-

강진하,박성종,정인수 한국펄프종이공학회 1998 펄프.종이기술 Vol.30 No.3

This study was carried out to bleach the Pinewood kraft pulp without the elemental chlorine using the xylanase or wastewater(We:wastewater enzymes) effluented from the submerged biofilter reactor containing the fungi, Phanerochaete sordida YK-624. So in this research, the proper treatment conditions(pH, temperature, dosage and time) were investigated respectively. And after the various kinds of multistage bleaching of pulps, the properties of pulps were tested. From the experimental results, we can conclude as follows. In the treatments of Pinewood kraft pulps with xylanase, the proper pH, temperature, enzyme dosage and time were 8.0, $35^{\circ}C, 400EXU/kg and 3 hr. respectively. And in the case of treatment with a wastewater(We) effluented from the submerged biofilter reactor, the proper pH, temperature and time were 5.0, $37^{\circ}C and 3 hr. respectively. On the other hand, Pinewood kraft pulps were bleached by the method of a multistage bleaching using xylanase or We instead of elemental chlorine. Consequently, the strengthes and brightnesses of pulps bleached by the method mentioned above were lower than those of pulp bleached by the conventional method using the elemental chlorine. But it is possible to improve the brightnesses through the increase of chlorine dioxide dosage or use of hydrogen peroxide in the final bleaching stage.

활엽수크라프트펄프 및 박테리아 셀룰로오스부터 제조한 종이의 물성

조남석,김영신,박종문,민두식,안드레레오노비치 한국펄프종이공학회 1997 펄프.종이기술 Vol.29 No.4

Most cellulose resources come from the higher plants, but bacteria also synthesize same cellulose as in plants. Many scientists have been widely studied on the bacterial cellulose, the process development, manufacturing, even marketing of cellulose fibers. The bacterial celluloses are very different in its physical and morphological structures. These fibers have many unique properties that are potentially and commercially beneficial. The fine fibers can produce a smooth paper with enchanced its strength property. But there gave been few reports on the mechanical properties of the processing of bacterial cellulose into structural materials. This study were performed to elucidate the mechanical properties of sheets prepared from bacterial cellulose. Also reinforcing effect of bacterial cellulose on the conventional pulp paper as well as surface structures by scanning electron microscopy were discussed. Paper made from bacterial cellulose is 10 times much stronger than ordinary chemical pulp sheet, and the mixing of bacterial cellulose has a remarkable reinforcing effect on the papers. Mechanical strengthes were increased with the increase of bacterial cellulose content in the sheet. This strength increase corresponds to the increasing water retention value and sheet density with the increase of bacterial cellulose content. Scanning electron micrographs were shown that fine microfibrills of bacterial celluloses covered on the surfaces of hardwood pulp fibers, and enhanced sheet strength by its intimate fiber bonding.

비목재펄프를 이용한 도공원지의 특성이 도공지의 물성 및 인쇄적성에 미치는 영향(I)

임현아,강진하,이용규 한국펄프종이공학회 2000 펄프.종이기술 Vol.32 No.3

This study was carried out to investigate the effect of the type of base papers containing Sw-BDP, HW-BDP and Bamboo-BKP on the properties and printabilities of coated papers. Also it was intended to evaluate the effect of coated paper prepared with anionic and amphoteric latex based coating color. The results obtained from this study were as follows. The fiber length of Bamboo-BKP was observed longer than that of the Hw-BKP and shorter than that of the Sw-BKP. This has effect on physical properties. Therfore the results of mea-suring physical properties were higher ratio of Sw-BKP physical properties tended to be slightly higher with the increase I the mixing ratio. Considering the optical properties of base papers the highest opacity was obtained in case of the Hw-BKP and the second appeared Bamboo-BKP. On the other hand smoothness roughness and air permeability of Bamboo-BKP were lower than those of wood pulp and the optical properties of coated papers tended to show the similar with those of base papers. The ink receptivity and print gloss of the coated papers for Bamboo-BKP were lower than those of wood pulp. As the mixing ratio of Sw-BKP was increased the properties and printabilities were improved slightly. Meanwhile amphoteric latex was improved the optical properties and printability of coated papers.

비목재펄프를 이용한 도공원지의 특성이 도공지의 물성 및 인쇄적성에 미치는 영향(II) -볏짚 표백 크라프트펄프-

임현아,강진하,이용규 한국펄프종이공학회 2000 펄프.종이기술 Vol.32 No.4

This study was carried out to investigate the effect of the type of base papers containing rice straw-BKP on the properties and printabilities of coated papers. Also, it was intended to evaluate the effect of coated paper prepared with anionic and amphoteric latex based coating color. The results obtained from this study were as follows. The fiber length of rice straw-BKP was observed much shorter than those of the wood pulps(Sw-BKP, Hw-BKP). This has effect on physical properties. Therefore, the results of measured physical properties were much lower than those of wood pulps. Also, physical properties tended to increase slightly with the increase of the mixing ratio of Sw-BKP. Opacity of the base paper containing rice straw-BKP, was higher than that of the wood pulps. As the mixing ratio of Sw-BKP increases the opacity tended to decrease. On the other hand, smoothness and roughness to rice straw-BKP were similar with Sw-BKP and its air permeability was lower than those of wood pulps. The optical properties of coated papers containing rice straw-BKP tended to be similar to those of other base papers. The ink receptivity of coated papers containg rice straw-BKP was higher than those of wood pulps and printing gloss was similar to wood pulps. The mixing ratio of Sw-BKP, the ink receptivity and printing gloss of rice straw-BKP were showed no difference irrespective the mixing ratio of Sw-BKP. Meannwhile, amphoteric latex improved the optical properties and printability of coated papers.

볏짚을 이용한 소다-안트라퀴논 펄프 및 알칼리성 아황산염-안트라퀴논 펄프 제조

강진하,박성철,박성종 한국펄프종이공학회 1997 펄프.종이기술 Vol.29 No.3

This study was carried out to investigate the proper cooking conditions of soda-anthraquinone and alkaline sulfite-anthraquinone pulping of rice-straw, and get basic data f9r the use of rice-straw chemical pulp through the test of characteristics and physical properties of pulps made in the various cooking conditions From the experimental results , we can conclude as follows. In the soda-anthraquinone pulping of rice-straw, the optimum cooking conditions were 60 min. at $150^{\circ}C$ in the amount of caustic soda of 20% with the addition of anthraquinone(0.05%). And total yield, Kappa No. and brightness of pulp made in the condition above mentioned were 41.9%, 7.7 and 51.1 respectively. In the alkaline sulfite-anthraquinone pulping of rice-straw, the proper mixing ratio of cooking chemical(caustic soda : sodium sulfite) was 50:50. And the optimum cooking conditions were 60 min. at $150^{\circ}C$ in the amount of cooking chemical of 20% with the addition of anthraquinone(0.05%). At that time, the total yield, Kappa No, and brightness of pulp were 50.1%, 9.1 and 40.2 respectively. As a result, the alkaline sulfite-anthraquinone pulping was superior to the soda-anthraquinone pulping in the aspect of yield, but inferior in the viewpoints of Kappa No. and brightness. For the comparison of qualities of pulps made in the various cooking methods and conditions, the physical properties of four sorts of pulps were tested. As a result, soda-anthraquinone pulps were superior to alkaline sulfite-anthraquinone pulps in the various strengths excluding tear strength and brightness. On the other hand, pulps made in the condition of addition of cooking chemical of 20% were superior to pulps in the dosage of 15% in the aspects of all the strengths and brightness.

목질계 Biomass의 변환이용(제1보)-기계펄프로부터 용해용펄프의 제조-

양재경,임부국,이종윤 한국펄프종이공학회 1997 펄프.종이기술 Vol.29 No.3

Dissolving pulp is a low yield(30∼35%) bleached chemical pulp that has a high cellulose content (95% or higher) suitable for use in cellulose derivatives such as rayon, cellulose acetate. This research was studied for dissolving pulp preparation as the raw material of viscose rayon from commertial pulps. (TMP, CP, DIP) In the change of pulp(cellulose) characteristics after sodium hypochlorite and solvolysis treatment. the following results were obtained In the case of sodium hypochlorite pretreatment, we have obtained pulp that high purity cellulose, but degree of polymerization was inclined to decrease less than 170∼240. Comparing sodium hypochlorite pretreatment and solvolysis pretreatment, solvolysis pretreatment is superior to sodium hypochlorite process for making dissolving pulp. We think that the low degree of polymerization of cellulose because of increasing degradation of cellulose during delignification treatment.