• 펄프종이기술
• /
• 제47권2호
• /
• pp.34-41
• /
• 2015

Recovered paper has been widely used as a main raw material of papermaking in Korea. Recycling of recovered paper helps to reduce production cost and preserve an environment. To recycle recovered paper efficiently, de-inking is a key process in recycling mills. De-inking process would be affected by various influencing factors such as the type of de-inking agent, mixed ratio of recovered paper, season, and process conditions. In this study, fatty acid and nonionic surfactant were used as the de-inking agent in froth-flotation process of mixed recovered paper. De-inking properties of mixed recovered paper were investigated according to the addition level of each chemical. Nonionic surfactant had a small effect on de-inking efficiency of mixed recovered paper due to decreased reject. As the additional level of fatty acid increases, fragmented ink particles increased and then optical properties of recycled paper decreased because fragmented ink particles adsorbed onto the fiber surface.

• 한국안전학회지
• /
• 제11권4호
• /
• pp.90-96
• /
• 1996

This paper examines the De-inking characteristics of mechanical methods using the newly developed De-inking machine along with experiments to enhance the manufacture of recycled kraft pulp with the addition of newspaper. This study concluded that : First, the De-Inking ratio was affected by shear stress and friction resistance operating In the stainless steel net. Second, the brightness improvement ratio was raised by 6.2% under the following conditions : 120rpm rotor speed, 2.18% concentration, using two treatment cycles. Third, it was shown that the tearing strength was improved by about 10 to 20% , and the tensile strength remained the same when recycled kraft pulp was added with 20% wasted paper. In sum, by these experiments we have proven that the performance of the newly developed De-inking machine can be improved.

• 공업화학
• /
• 제5권6호
• /
• pp.917-924
• /
• 1994

고지 재생 시뮬레이션 기술에 의한 최적 탈묵제의 개발에 관해서 개략적으로 소개하였다. 금후에도 지구환경 보호차원과 자원의 효율적 이용의 측면에서 재생 펄프의 필요성은 더욱 높아짐과 동시에 품질면에 있어서도 보다 한층 고품질의 펄프가 요구된다고 생각된다. 그리하여 고성능 탈묵제 및 탈묵시스템의 개발에 주력하여 고지 처리기술의 진보와 고품질 펄프의 재생에 다소나마 공헌하고자 한다.

• 펄프종이기술
• /
• 제47권4호
• /
• pp.88-95
• /
• 2015

The main sources of recovered paper for newsprint are old newsprint (ONP) and old magazine (OMG). Recently, a lot of advertisement flyers are flowing into bales of ONP and portion of OMG is increasing in recovered paper because the consumption level of coated paper increases. In this study, nonionic surfactant and fatty acid were used as the de-inking agent for froth-flotation process of mixed recovered paper to investigate the effect of increased mixing ratio of OMG. De-inking efficiency of nonionic surfactant decreased as the mixing ratio of OMG increased; ink removal efficiency of froth-flotation is poor, however, the reject ratio increases due to ash from OMG. In comparison with nonionic surfactant, the ash from OMG had a little effect on reject ratio and optical properties of fatty acid applied flotation accept. If nonionic surfactant and fatty acid are added to pulper and flotation cell sequentially, excessive ash from OMG may not give an adverse effect on de-inking efficiency of mixed recovered paper.

• 펄프종이기술
• /
• 제39권5호
• /
• pp.12-19
• /
• 2007

Enzymatic deinking method can avoids the alkaline environment as usual required in chemical deinking, which consequently cuts chemical costs and reduced the white water pollution. The electrostatic wastepaper was dinked with commercial cellulolytic enzymes and surfactant in neutral pH and the effectiveness of deinking and the physical properties of deinked pulp were evaluated. The disintegrating efficiency of the electrostatic wastepaper in neutral pH was enhanced with enzyme treatments. Although the freeness of deinked pulp with enzymes was higher than that of deinked pulp with chemical de inking agents, the brightness of the enzymatic deinked pulp was slightly lower than that of the chemical deinked pulp. But, by additions of nonionic surfactants, the brightness of deinked pulp was increased with less residual ink particles and mechanical properties of enzymatic deinked pulp was improved compared to the deinked pulp of conventional alkaline method.