• 펄프종이기술
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• 제48권2호
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• pp.56-60
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• 2016

Neutral or alkaline papermaking provides many advantages in paper strength and processing conditions. It also provides the opportunity of using calcium carbonate fillers in papermaking. These diverse advantages have made almost all paper machines of printing and writing papers run under neutral and alkaline conditions. On the other hand, linerboard machines, which use recycled papers as a raw material, are running under acid conditions using a rosin sizing system. Because the recycled raw materials used by the linerboard industry contain significant amounts of alkaline papers, the linerboard industry has an interest in the possibility of using the neutral or alkaline papermaking opportunity. In this study, the compatibility of the recycled linerboards under neutral or alkaline papermaking conditions was examined by recycling them under various pH conditions. The sizing degree of the papers recycled under neutral or alkaline was significantly lower than that of acid formed papers indicating that during the neutral or alkaline recycling process the rosin sized papers lost their sizing efficiency. Recycling of acid formed linerboards under neutral or alkaline conditions increased the amount of foam, and the foam contained substantial amount of solid materials derived from the acid sizing systems. Use of cationic polyelectrolytes including PEI and poly-DADMAC improved the sizing degree of the recycled papers under neutral and alkaline conditions. PEI decreased the foam generation as well while poly-DADMAC did not show any reducing effect of the foam. These results suggest that PEI forms coordinate bonds with rosin acid and precipitate them onto the surface of recycled fibers, while the reaction products between poly-DADMAC and rosin acid ions still remain water soluble under neutral or alkaline conditions.

• 펄프종이기술
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• 제39권3호
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• pp.1-11
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• 2007

To evaluate the quality of waste paper used for the manufacture of linerboard, the types of papers and foreign materials in compressed waste paper currently used were investigated. The recycled fibers were obtained from printing paper, newspaper, wrapping paper, white coated paperboard and corrugated container. Their fibers were observed by using a microscope, and the mechanical properties of the recycled papers manufactured from the recycled fibers were investigated. The compressed wastepaper was composed of 54% paperboard, 20% printing paper, and 20% newsprint. The content of foreign materials was about 4%, showing higher contents compared to 1% of foreign substances provided by Korea paper manufacturers' association. The types of foreign materials were various, which include vinyls, plastics, metals, woods, styrofoams, and cloths. Sound fibers were generally observed in the recycled fibers of printing papers and wrapping paper. The recycled fibers of white coated board, corrugated container and newsprint showed to be generally damaged. The whiteness of each recycled fiber were highly affected by pulp bleaching and ink-particle mixing conditions. The values of breaking length and burst index were lower than those for corrugating medium and liner board specified in KS. Although the anatomical characteristics of recycled fibers varied, their strengths appeared to be similar. This result may be explained by the use of non-deinked fiber.

• 한국재난정보학회 논문집
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• 제18권1호
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• pp.116-128
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• 2022

연구목적: 첫째, 국내에서 재생복사용지가 많이 사용되지 않고 시장이 활성화되지 못한 이유를 파악하고, 둘째, 복사용지가 재생복사용지로 대체되었을 경우의 환경적 효과를 알아본다. 셋째, 재생복사용지의 시장을 활성화시킬 수 있는 개선방안을 도출한다. 연구방법: 재생복사용지에 대한 인식을 조사하기 위해 설문조사를 실시하였고 그 결과를 SPSS를 이용하여 분석하였다. 또한 Life Cycle Assessment 기법과 Paper Calculator V4.0을 사용하여 재생복사용지로의 전환에 따른 환경적 효과를 측정한다. 연구결과: 설문조사 응답자들은 재생복사용지의 낮은 사용경험에도 불구하고 재생복사용지에 대한 필요성을 인정하고 있으며 품질에 대한 만족도도 높은 편이었다. 또한 고지율40% 재생복사용지의 시장점유율이 10%로 상승 시 6만 톤의 CO₂ 감소의 환경적 효과를 확인하였다. 결론: 인식조사 및 시장조사 결과에 대한 분석을 통하여 재생복사용지 시장 활성화를 위한 5가지 개선방안을 제시하였다.

• 한국식품위생안전성학회지
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• 제14권1호
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• pp.67-75
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• 1999

The new approach using the Peak Pattern Method was conducted for the analysis of polychlorinated biphenyls (PCBs) from the papers or paper products to provide certain hygienic data for the recycled papers as well as white papers. The height of the each peak, obtained from the PCBs standards, was transformed to the spectrum to compare with that of the samples. In addition to the results of the single PCBs standards, the pattern of mixed PCBs standards with the adequate concentration and ratios were obtained prior to the analysis of the paper samples. The test showed excellent repetition within 5% variation, and the recoveries of PCBs ranged from 92% to 97%. The PCBs, considered as a hazard material, were analyzed using the Peak Pattern Method from six different types of paper samples including the roll tissue. It could not find the same pattern of the PCBs peaks from all of the paper samples.

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 2006년도 PAN PACIFIC CONFERENCE vol.1
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• pp.117-121
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• 2006

Virgin bleached kraft pulp, CPO (computer printout) and white ledgers are main raw materials used in tissue mills. The utilization rate of recycled fibers and virgin pulp in South Korea tissue industry are 90% and 10%, respectively. To improve brightness of printing grades the use of 'fluorescent whitening agents (FWAs)' or 'optical brightening agents (OBAs)' has been increased. When recycling these papers for tissue production, it is unavoidable that FWAs contained in recycled papers flow into tissue production lines and remain in the products. And this draws great attention from the public. This study was carried out to develop a technology for the removal of fluorescent whitening agents from recycled fibers. Enzymatic removal of FWAs was evaluated as a method to remove FWAs from the recycled fiber. The ${\alpha}-amylase$ that degrades starched used for surface sizing of fine papers and contained substantial condition is needed to prevent the re-adsorption of FWAs on fibers. The temperature of pulp suspension was another important factor affecting on FWA removal. The higher the temperature, the greater the efficiency of removing FWAs was obtained. Optimum pH and temperature for the effective removal of FWAs were suggested to be pH 8.5 and $65^{\circ}C$, respectively. The enzymatic removal of FWAs showed a great synergistic effect when proper control in pH and temperature was made.

• 펄프종이기술
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• 제45권4호
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• pp.65-74
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• 2013

In the manufacture of corrugated box, the fibrous raw materials are mainly consisted of recycled papers, such as KOCC(Korean Old Corrugated Container), kraft sack, and AOCC(American Old Corrugated Container). Among these recycled waste paper, the proportion of KOCC is relatively higher than others in fibrous raw materials. Generally, KOCC shows some poor fiber properties and contains hazardous heavy metal sources. Therefore, it is to evaluate the property of recycled paper sources for eco-friendly corrugated box manufacture. In this study, the physical and mechanical properties of 3 kinds of recycled fibers and their mixed stocks were analyzed. The environmental assessment was also evaluated by analyzing the 4 representative heavy metal contents and evaporation residues in waste papers. As the results, KOCC showed the poorest fiber qualities and had the highest heavy metal contents and evaporation residues among the recycled fibers. Finally, the mechanical strength properties were increased by decreasing KOCC proportion of mixed stock conditions. In addition, the heavy metal contents and evaporation residues were also decreased by increasing recycled AOCC and kraft sack proportion.

• 펄프종이기술
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• 제44권3호
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• pp.56-62
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• 2012

Recycled pulp therefore play a very important role in the paper industry today as a substitute for virgin pulp. In many countries of the world, the paper industry could not exist as it does without recycled pulp. Because, this is mainly due to economic reasons. Particularly in our country, the additional reason is the scarcity of native pulpwood resources. Therefore, the use of recycled pulp is very important. This study was aimed to apply recycled pulp to textbook paper. So we made a paper containing 30% recycled pulp and investigated about print quality, such as color reproduction, trapping, contrast, dot gain, gloss and print through. The results showed that is similar to existing textbook papers.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2000년도 봄 학술발표회 논문집
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• pp.521-526
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• 2000

The structural behavior of the members using recycled coarse aggregate is investigated in this papers. The members considered this study are subjected to shear ad bending simultaneously. A series of test beam specimens using recycled coarse aggregate is made for the structural test. These specimens are manufactured using the concrete for the compressive strength of 280kg/$\textrm{cm}^2$ with recycled aggregate ratio of 0%, 20%, 40%, 60%, 80% of total aggregate volume, respectively. The main object of this test is to investigate the influence of the using recycled aggregate to the cracking strength of the member subjected to flexure and shear and the post cracking behavior.

• 펄프종이기술
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• 제40권5호
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• pp.11-19
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• 2008

The paper established a new method for fast measurement and characterizing of sub-visible dirt of recycled paper which is too small to be seen with naked eye. This method provided a new way for the evaluation of recycled paper that is hard to be characterized by the conventional method. Two effective thresholding algorithms HA and SDA were compared and their applicable conditions were discussed. Results showed that the HA could be used for un-printed paper while SDA is suited for recycled papers. The gloss of paper samples was measured and the relation between gloss and sub-visible dirt was investigated. The significant effect of this method for characterizing and comparing paper was exhibited. The experiment results indicated that sub-visible dirt measuring method could be a complementariness of the conventional methods.

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 2001년도 추계학술발표논문집
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• pp.168-182
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• 2001

A new concept of stock preparation for the increase of bending stiffness in paper and board was proposed. The 'stiff' fibers, which were mechanically not treated or treated slightly to remove fiber curls, were combined with extensively refined fibers (ERF) to produce higher stiffness papers than those where the whole fibers were refined. The combination of 'stiff' fibers and extensively refined fibers produced higher stiffness at the same tensile strength than the control furnish, in which all the fibers are refined together. In this concept, the fibers from recycled papers could be as much useful as the virgin fibers as long as they are stiff enough or they can produce highly bondable fiber fractions by extensive refining. Use of the concept in real paper mill needs considerations such as increase of refining energy, slower drainage, and added drying burden, but savings of wood fibers, utilization of more recycled fibers, and increase of physical properties may offset the negative concerns. The success of this concept implementation in mills, therefore, depends on the wood fiber market around the mills and the proper decision making for the papermakers about how to apply this concept.