• 펄프종이기술
• /
• 제48권2호
• /
• pp.83-90
• /
• 2016

Increasing the amount of filler in paper is of high interest for paper industry while maintaining its key sheet quality properties. In this study, a MFC-GCC composite, made through a co-grinding NBSK (Northern bleached softwood kraft) pulp with a ground calcium carbonate (Intracarb 60), was used as a strength aid in paper in order to evaluate a potential cost reduction through filler increase without sacrificing paper quality. Hand-sheets were made of NBSK and/or eucalyptus pulp by using white water recirculation in a Tappi sheet former and was compared its properties without or with MFC additions at different filler levels. It was found that the MFC-GCC composite has a large surface area compared to the fiber, allowing the formation of more hydrogen bonds in the web, thus giving natural strength to the paper. Overall results are encouraging that the MFC-GCC composite allows papermaker to reduce basis weight and maintain critical sheet properties.

• 펄프종이기술
• /
• 제30권2호
• /
• pp.55-61
• /
• 1998

This treatment was applied to bleached softwood kraft pulp handsheets in an effort to improve physical strength of paper. Paper strength was improved by esterification of cellulose and polycarboxylic acid. Because hydrogen bond of carboxyl group is stronger than that of hydroxyl group, polycarboxylic acid forms stronger hydrogen bond than cellulose does. 1,2,3,4,-cyclopentanetetracarboxylic acid (CPTA) and sodium dihydrogen phosphate ($NaH_2O_4$) were used as polycarboxylic acid and catalyst, respectively This reaction was confirmed by the weight gain of the handsheets, by FTIR spectrum and by changes in mechanical properties of sheets. Wet tensile strength was improved when handsheets were treated with polycarboxylic acid. However, tear strength and burst strength decreased.

• KSBB Journal
• /
• 제14권4호
• /
• pp.470-475
• /
• 1999

Several enzyme were applied to Laubholz Bleached Kraft Pulp(LBKP) to evaluate the influence on beatability which was measured in Schopper Riegler value, and the results were compared with untreated pulp. Among the types of enzyme, cellulase was found to be the most effective. Addition of cellulase increased the beatability by 28% at optimum condition. Strength properties such as tensile strength and folding endurance also increased with enzymatic treatment by 12% and 46%, respectively. However, excessive dosage of cellulase had an adverse effect on strength properties in spite of the high beatability. Fibrillization by cellulase and destruction of fiber by excessive reaction was observed by Scanning Electron Microscopy(SEM).

• 펄프종이기술
• /
• 제33권3호
• /
• pp.59-68
• /
• 2001

Essential oils extracted from Chamaecyparis obtusa were applied to make antibacterial corrugating liner. The quantitative analysis of the essential oils was carried out by GC-MS, which showed that the monoterpenes as a basic component of the essential oils extracted from Chamaecyparis obtusa in the domestic mountain were greater in amount than those in China. The antibacterial activity was then examined with Tyromyces palustris and gram-negative/positive bacteria. The papers treated with the essential oils desplayed great resistance against T. Palustris and gram bacteria but the best results were obtained with the handsheet formed by softwood bleached kraft pulp rather than the liner by OCC. The low antibacterial activity of the liner was considered to be due to starch components which could be readily attacked by the fungi.

• 펄프종이기술
• /
• 제39권1호
• /
• pp.1-7
• /
• 2007

Internal fibrillation of pulp fiber is an important factor affecting paper properties. Internal fibrillation of pulp fiber is usually introduced with several kinds of modifications of fiber by the mechanical treatment such as refining, high shear and/or high consistency mixing, etc. Unfortunately there are no standardized methods that can characterize the extent of internal fibrillation and its contribution on the paper properties. The purpose of this study is to try and find the potential methods that can characterize the internal fibrillation of pulp fiber quantitatively. Softwood bleached kraft pulp was treated with Hobart mixer to introduce the internal fibrillation without the significant fiber damage and external fibrillation. The extent of internal fibrillation was increased with the increase of mechanical treatment consistency. Several fiber properties were measured to find the potential means that could characterize and quantity the internal fibrillation. Laminated area could not be used as a means for quantifying the internal fibrillation because of the effect of swelling and the different internal fibrillation behavior at different mechanical treatment consistency. Micro and macro internal fibrillation models were proposed for describing the different behavior for the mechanical treatment at low and high consistencies of pulp. The Internal fibrillation showed good correlation with swelling of fiber wall. This trend was confirmed through the measurement of wall thickness and/or cross section area of fiber. Therefore the internal fibrillation possibly can be described as the indices indicating the change of wall thickness and/or cross section area.

• 상하수도학회지
• /
• 제8권3호
• /
• pp.9-18
• /
• 1994

활성슬러지 공정을 이용하여 Kraft 펄프공장에서 배출되는 유출수에 잔류하는 만성독성의 제거가능성을 평가하기 위하여 pilot plant를 운전하였다. 독성 이외에도 폐수내의 BOD, SS, resin과 fatty acids, 색도, 그리고 AOX와 같은 오염물질의 제거효과도 측정되었다. Pilot plant는 정상상태에서 약 10주 동안 운전되었으며 운전기간 동안의 평균 F/M 비율은 0.28, 그리고 sludge age는 8.4일로 계산되었다. 평균 MLSS 농도는 4,309mg/l이었으며 이중 휘발성 물질은 57%이었다. 운전기간 동안, BOD 제거계수(k)는 $30^{\circ}C$에서 8.2/일 이었으며 BOD 제거율은 full-scale 운전시보다 3~6% 정도 낮은 84%로 나타났다. 활성슬러지 유출수의 만성독성 시험은 Dinnel 방법과 BML 방법이 활용되었으며, 시험결과 pilot plant 활성슬러지 시스템에서도 효율적인 운전을 통하여 90% 이상의 독성제거가 가능함을 알 수 있었다. Pilot plant의 진 공정을 통해서 색도와 AOX의 제거는 매우 미미하였으나 resin과 fatty acids는 뛰어난 제거율을 나타내었다.

• 펄프종이기술
• /
• 제46권4호
• /
• pp.69-75
• /
• 2014

Effects of alkali swelling of HwBKP (hardwood bleached kraft pulp) at a low concentration below 2 percent (based on the oven-dried weight of pulp) on handsheet properties were investigated. Swelling treatment of HwBKP was performed at various low NaOH concentrations with/without beating. Then, the changes in handsheet properties were evaluated in terms of bulk, optical and strength properties. It was found that bulk was slightly increased when the alkali concentration was increased. When the pulp was only swollen without beating, paper optical and strength properties was slightly decreased or not changed with alkali concentration. When the pulp was alkali-swollen after beating, paper strength and opacity showed almost no changes while brightness was increased. When the pulp was beaten after NaOH swelling, alkali concentration showed almost no effect on brightness and opacity of paper. Paper strength was slightly decreased with alkali concentration, suggesting that alkali pretreatment before refining could adversely affect refining efficiency.

• 펄프종이기술
• /
• 제46권3호
• /
• pp.65-72
• /
• 2014

In this study, effects of alkali swelling at low concentration below 2 percent on properties of hardwood bleached kraft pulp (HwBKP) were elucidated. Swelling treatment of HwBKP was performed at various NaOH concentrations with/without beating. Then, the swelling characteristics of pulp fiber was evaluated by measuring the solvent retention values such as water retention value (WRV) and isopropyl alcohol retention value (LRV). It was found that fiber characteristics were influenced by NaOH swelling even at low alkali concentration and beating treatment as well. The values of WRV and LRV were decreased when the alkali concentration was increased. It is the result from the decreased acidic groups of pulp which were formed during beating. The acidic groups could be neutralized and then removed by alkali. The difference between WRV and LRV was decreased with increasing alkali concentration while the difference was increased when the alkali swollen pulp was beaten. In addition, the crystalline structure of HwBKP was almost not changed while the crystallinity was influenced by swelling treatment at a low alkali concentration.

• 공업화학
• /
• 제10권3호
• /
• pp.367-373
• /
• 1999

OCC의 구성 특성을 조사하고 OCC로부터 elemental chlorine free (ECF)나 totally chlorine free (TCF) 표백을 통한 백색도 85% (ISO) 이상의 인쇄 및 필기용지를 제조하기 위한 연구가 수행되었다. American old corrugated containers (AOCC)는 Korean old corrugated containers (KOCC)보다 섬유길이가 길며, 주로 장섬유로 구성되어 있고 전자의 경우 약 80%가 unbleached kraft pulp (UKP)로 구성되어 있으나 후자는 20% 정도였다. 또한 KOCC의 경우 회분함량 (9.7%)과 NaOH 추출물 (19.3%)이 AOCC보다 현저히 높았다. AOCC로부터 ECF 표백이 가능한 펄프 (kappa no. 25이하, 수율 70%)를 생산하기 위한 증해조건은 활성알칼리 20%, 황화도 25%, Anthraquinone (AQ) 0.1%, 펄핑온도 $170^{\circ}C$, 증해시간 90분이다 (kappa no. 22.6, 수율 68%). KOCC의 경우는 증해시간을 60분으로 단축시킬 수 있었다. (kappa no. 16.4, 수율 66%) 증해된 AOCC 펄프를 TCF나 ECF 표백단계를 거치면 백색도 85% (ISO) 이상의 펄프를 생산할 수 있었다. 그러나 KOCC 펄프는 TCF 표백으로서 목표 백색도를 달성할 수 없었다. 표백 KOCC 펄프는 표백 AOCC 펄프에 비하여 연장지수가 낮으나 파열지수와 인열지수는 오히려 높은 경향을 나타내었다.

• 한국펄프종이공학회:학술대회논문집
• /
• 한국펄프종이공학회 2008년도 춘계학술대회
• /
• pp.191-197
• /
• 2008

In this study, as a fuel filter for automobiles, base paper which can filtrate the polluted particles must satisfy with the standards of each vehicle. and a filter of impregnation paper made that combining the base paper with the resin. Therefore, They were wanted to found out the factors that affect base paper and impregnation paper according to content of HPZ, Mulberry pulp(MP), Laub holze bleached kraft pulp(LBKP). The most important things we wanted to find out in base paper and impregnation paper test were weight, thickness, air permeability, burst and tensile strength, maximum pore size and mean pore size, stiffness. we wanted to measure a rate of change of these condition by adjusting a rate of mixing for HPZ, MP and LBKP. Moreover, It suited for an impregnation paper mixed with a rate of mulberry pulp 20%, HPZ 40% and LBKP 40%. Used resins in this study was Phenol, Acryl, PVAc. And as every resins, sample was divided into existence and nothing of embossing. as a fuel filter for automobiles, It was appeared that the suitable condition of base paper was a rate of mixing for HPZ(40%), MP(20%) and LBKP(40%).