• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.42 no.3
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• pp.50-57
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• 2010

A mill trial was performed in a kraft paper mill in order to evaluate the possibility of utilizing dual polymer dry strength aids system consisting of cationic PVAm and anionic PAM. It was found that the cationic PVAm - anionic PAM dry strength additives can improve paper strength without significantly disturbing the stability of the kraft papermaking process when virgin UKP was used as a furnish. Tensile strength (25.3% in machine direction, 48.4% in cross machine direction), elongation of paper (31.6%, 15.6%) and tensile energy absorption (48%, 54%) were improved. Air permeability of the kraft paper was improved as well (22%). Tear strength was decreased with PVAm dry strength aids system, but it can be compensated with decreasing refining degree. In addition, the mill trial results indicate that highly air permeable kraft sack paper can be produced by the addition of PVAm dry strength agents at the stock with reduced freeness.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.42 no.2
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• pp.95-101
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• 2010

For the development of higher-sizing performance of paper, a sizing agent using recycled PET was synthesised. Polyester resin was extracted from wasted PET by subcritical hydrolysis and finally modified to synthetic sizing agent by mixing water-disperse PET with triphenyl phosphite(TPP). The modified PET was considered as an internal sizing agent in different wet-end papermaking conditions. The optimum condition in sizing efficiency was obtained in initial pH of 6.5 in case of rosin+alum system, and 7.5 in case of rosin+alum+PET system, respectively, and in addition amount of PET 3%. The sizing efficiency was also closely related according to the fiber properties of wet-end slurry, such as virgin fibres from UKP and recycled fibres from KOCC. The application of modified PET was good in strength improvement of paper, specially in tensile strength.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.34 no.5
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• pp.63-69
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• 2002

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. apply this concept.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.45 no.6
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• pp.24-29
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• 2013

In this study, we investigated the applicability of PCC(precipitated calcium carbonate) as a raw material for the manufacture of duplex-board. Papers were made with white-ledger stock collected from the actual duplex-board mill and PCC in a laboratory, and paper properties including bulk, ash content, tensile strength, burst strength, brightness and opacity were measured. The effect of PCC on the drying energy of duplex-board was also determined by measuring the moisture content of wet web and calculating drying energy reduction. PCC increased bulk and ISO brightness significantly, which means PCC can decrease the use of virgin pulp and recycled fibers. PCC decreased the moisture content of wet web, which means PCC can decrease drying energy consumption. However, paper strength decreased as addition levels of PCC addition increased. Therefore, the addition level of PCC must be determined considering the reduction of paper strengths.

• Journal of Energy Engineering
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• v.27 no.2
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• pp.81-88
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• 2018

Every day a huge amount of paper is being used, most of them are thrown after using. This directly impacts on the environment. Therefore, waste paper management is necessity to protect the environment from its annihilation and pollution. Paper recycling products consist of printing paper, newspaper, corrugated containers, magazine paper and so on. Reuse waste paper will reduce the consumption of wood and virgin pulp as recycling one ton of newsprint can save approximately 1 ton of wood, meanwhile recycling 1 ton of printing paper can save more than 2 tons of wood. With increasing recycling rates, lower quality paper fractions may be included. Thus the selection of a paper recycling technology is a crucial first design consideration. The paper recycling must be accompanied by appropriate technology to manage a huge volume of wastepaper. The specific objectives of this study were as follows: (1) comprehensive literature reviews of paper production and consumption, (2) figure out about paper recovery and utilization, (3) investigate the paper recycling in the sustainable times, (4) introduce eco-friendly recycling technology to paper industry.