• 한국가금학회지
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• 제24권2호
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• pp.59-66
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• 1997

Optimum drying conditions to utilize porcine blood from slaughter house for blood meals, and the effects of blood meals on growth in broiler chicks were investigated. Moisture and protein con-tents of slaughter porcine blood were 79.8 and 16.4%, respectively. The protein contents of the flash dried blood meals at 80˚C were not different from those of the spray dried blood meals at 160 and 190˚C, but higher by 17% relative to those of the spray dried blood meals at 80 and 120˚C. Results from protein analysis by SDS-polyacrylamide electrophoresis showed that flash dried blood meals at 80˚C and spray dried blood meals at 160˚C were better than spray dried blood meals at 80, 120 and 190˚C in terms of protein quality. In Feeding Trial I with broiler chicks, body weights of chicks fed 2, 4 and 6% flash dried blood meal diets at 80˚C were increased at 35 days by 5.6, 7.9 and 4.0%, respectively, compared to control group(P<0.05). In Feeding Trial II, body weights of chicks fed 4 and 6% flash dried blood meal diets at 80˚C were increased at 42 days by 4.9 and 5.3%, respectively, compared to control group(P<0.05). Feed conversion ratios of chicks fed diets 4 and 6% flash dried blood meal diets at 80˚C were significantly improved at 42 days by 7.0 and 3.7%, respectively, compared to that of control group(P<0.05). The optimum drying condition of slaughter porcine blood seemed to be the flash drying method at 80˚C

• 한국축산시설환경학회지
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• 제3권2호
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• pp.133-143
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• 1997

Optimal conditions for collecting, storing and drying temperature to utilize slaughter porcine blood for blood meals and the effects of blood meal on growth in broiler chicks were investigated. Dry matter and protein contents of slaughter procine blood were 19.5% and 77%(dry basis), respectively. As for the composites of amino acids in the blood, aspartic acid, arginine, glycine, histidine, leucine, lysine, phenylalanin threonine were shown high. There was no significant difference between the collections by bloodletting and vacuumming in terms of microbial contamination. Storage of slaughter porcine blood showed no differences in protein, DNA and triglyceride contents and pH between the storage methods of freezing (-20$^{\circ}C$) and refrigerating (-4$^{\circ}C$). In case of room temperature storage, however, the decrease in pH and the appearance of new protein due to microbial contaminations increased as the storage periods were prolonged. When drying was done by flash methods, the drying period got shortened as the temperature became higher, yet protein and triglyceride were destoryed more. When drying was done over 120$^{\circ}C$, even at the same degree, the breakdowns of protein and triglyceride increased more as drying period got longer. In feeding trials of broiler chicks, dietary supplementation of the flash dried blood meal at 2% level showed significant difference in growth rate(P＜.05%). These results indicated that the appropriate handling and manufacturing of slaughter porcine blood enabled the blood to be used as a protein source for broiler chicks.

• 한국연소학회지
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• 제20권2호
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• pp.1-13
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• 2015

Drying, which is the oldest and most energy-intensive process, is an essential process for treatment of solid product. The specific procedure to design and evaluate the dryers, which are a rotary kiln dryer and a flash dryer, in case of drying the high-moisture coal was described. From determination of size to the heat and mass balance in one-dimensional model were conducted to evaluate the performance of dryers. Heat consumption, inlet gas temperature and size of the dryers were compared between a rotary kiln dryer and a flash dryer. Further considerations to evaluate the reactor elaborately were also discussed. Performance simulation of dryers along with the design procedure described here will provide helpful basis for understanding the concept of reactor design.

• 공업화학
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• 제28권3호
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• pp.313-317
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• 2017

지속적인 에너지 수요의 증가로 인하여 저등급 석탄이 새로운 에너지 자원으로서 인정받고 있다. 그러나 저등급 석탄의 높은 수분 함량으로 인하여 저등급 석탄의 이용 효율은 기존의 석탄 이용 플랜트들에서 이용하기에 부족하다. 따라서 저등급 석탄의 수분 함량을 낮추는 건조 공정이 요구되고 있다. 비록 다양한 건조 실험들이 진행되었으나, 고압조건에서의 건조 특성은 크게 연구되지 않았다. 이에 본 연구에서는 높은 수분 함량을 지닌 저등급 석탄(수분 함량: 21.5 wt%)의 급속 건조 특성을 가압 마이크로 상승관을 이용하여 고찰하였다. 압력(1-40 bar), 건조 온도($200-600^{\circ}C$), 마이크로 상승관 길이(2-6 m) 등의 운전 조건 변화에 따른 저등급 석탄의 건조 특성을 분석하였다.

• Korean Chemical Engineering Research
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• 제50권1호
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• pp.106-111
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• 2012

5 kg/hr 벤치규모 기류건조기를 이용한 고수분 석탄의 건조 특성을 알아보았다. 도착시료 기준으로 원료 석탄의 수분 함량 및 발열량은 각각 29.74 wt%, 4,270 kcal/kg이다. 가스유입온도 및 가스유입속도는 각각 $400{\sim}600^{\circ}C$ 및 10~20 m/sec이다. 원료 석탄의 입자크기는 $100{\sim}2,000{\mu}m$로 분쇄 및 분급하였다. 원료석탄의 수분제거율은 가스유입온도는 증가하고 가스유입속도는 감소할수록 급격하게 증가하였다. 건조석탄의 발열량은 5,100~5,900 kcal/kg으로 증가하였다. 기류건조를 통한 고수분 석탄 표면에서의 발생하는 화학적인 변화를 알아보기 위하여 FT-IR 스펙트럼 분석을 실시하였다. 그 결과 하이드록실, 카르복실 및 카보닐 피크에서 주요한 변화가 일어나는 것을 확인할 수 있었다.

• 한국산학기술학회논문지
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• 제13권11호
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• pp.5628-5636
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• 2012

본 연구에서는 하수슬러지를 효율적으로 건조시킬 수 있는 방법을 연구하고자 하였다. 슬러지 건조를 위해서는 슬러지 내 대부분의 함수율을 차지하고 있는 세포 내 함유수분을 제거시키는 것이 필요한데, 이에 대한 제거 장치로서 타격기류 건조장치를 적용하였으며, 직접 하수처리장에 파일롯 플랜트를 설치하여 실증실험을 실시하여, 이에 대한 운전특성과 적용가능성을 확인하고자 하였다. 주요 운전제어 변수는 슬러지 투입속도, 체인 회전속도, 공정온도 및 투입슬러지 함수율 변화 등이다. 체인의 회전속도가 증가할수록 생성슬러지 생성수율 증가 등 장치성능이 향상되었고, 공정온도가 상승함에 따라 건조효율이 증가하는 경향을 나타내었다. 투입슬러지 함수율은 60%일 때 생성슬러지 생성수율이 최대이고 함수율도 10% 내외를 나타내어 최적 조건임을 알 수 있었다. 슬러지 투입속도는 적정 투입속도 이상으로 투입 시, 생성슬러지 생산량은 증가하지 않는 반면, 오히려 잔류량만 증가하는 현상을 초래하였다. 위와 같은 실험결과로부터 장치의 최적 운전조건은 체인 회전수 1600rpm(최대속도), 최종 배출온도 $80^{\circ}C$, 투입슬러지 함수율 60%, 슬러지 투입속도 60kg/h이며, 이때 장치성능은 생성슬러지 생성수율 85.5%, 함수율 11.0%, 건조효율 81.7%으로 양호한 결과를 나타내었다.

• 청정기술
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• 제19권4호
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• pp.464-468
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• 2013

본 연구에서는 석탄 종류, 저등급석탄으로부터 첨가제의 종류, 입도분포 및 건조 방법에 따른 석탄-물 혼합연료(coal water fuel, CWF)의 고체함유량을 높이고자 하였다. 건조 방법에는 열풍 건조 방법(flash drying, FD), 유동층 건조 방법(fluidized bed, FB), 유중 건조 방법(oil deposit stabilized, ODS)을 사용하였다. 석탄 종류에 의해서 고체함유량 차이는 최대 20% 이상 보였다. 또한, CWF을 제조할 때 넣어주는 첨가제의 종류를 다르게 하여 실험한 결과 첨가제에 의해서 5%까지 효율을 더 높일 수 있었다. 석탄의 입도분포는 $75{\mu}m$ 이하의 미분탄이 80% 함유되어야 CWF의 성능이 향상되는 것을 관찰하였다. 3가지 건조 방법을 활용하여 CWF를 제조해본 결과, 안정화시킨 유중 건조 석탄이 원탄에 비하여 12% 정도 더 높은 고체함유량을 갖는 CWF를 제조할 수 있는 것을 알 수 있었다.

• 펄프종이기술
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• 제47권6호
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• pp.22-40
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• 2015

Cellulose fibers is one of the most abundant in nature. It has many distinctive features: abundant in nature, biodegradable, non-toxic, eco-friendly, sustainable, easy to fabricate, hydrophilic, and cost-effective. Cellulose fibers, known as pulp, is produced from cellulose-containing materials by the pulping process. As the raw material, wood has been most commonly used while recycled pulp has been also used to some degree. Thus, pulp usually refers to wood pulp. Generally, the pulp and paper industry is regarded as the commodity market where the cost should be much more important than the quality. It also belongs to a mature market where the growth is slow, or even in decline. Accordingly, technological development has been rather stagnant for the industry. Recently, however, the pulp and paper industry has faced very serious challenges. First, due to digital technology, there has been a steady decline in the need for pulp and paper products. The digital industry has continuously replaced printed products such as books, newspapers, and magazines. Second, there has been a trend initiated by developed countries to limit the use of wood as the raw material for the sake of environmental protection. This forces the industry to find a more efficient use of wood pulp as well as finding alternative, non-wood sources. Third, as an individual becomes wealthier and more conscious of health-care, the quality of a product becomes more important than the cost. Thus, a paradigm shift is needed from the cost-conscientious to the quality conscientious. The objective of this article is to review the technologies aimed at engineering cellulose fibers for producing high-value added paper products.

• 한국응용과학기술학회지
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• 제28권1호
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• pp.35-47
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• 2011

For the synthesis of water soluble acrylic modified epoxyester resin, fatty acid/epoxy ratio of 50/50 was used, and introduced maleic anhydride. Ratio of styrene/acrylic acid of acrylic monomers was fixed 85/15 and ratio of epoxyester/acrylic monomer was controlled 80/20, 75/25, 70/30, 65/35, and degree of neutralization were changed 65%, 80%, to 100%. As a result, 40% solids acrylic modified epoxyester resins were synthesized. Resins were evaluated water soluble stability, drying time, water resistant, storage stability and physical properties. And the white paints were prepared, and were evaluated viscosity, drying time, water resistance, adhesion, sagging, spray workability, gloss, salt spray resistance, skinning, whiteness and flash rust. As a result, the degree of neutralization of 100% and the ratio of epoxyester/acrylic monomer of 75/25 showed the best properties.

• Journal of Welding and Joining
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• 제7권2호
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• pp.60-69
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• 1989

The present study was aimed at investigating the effect of welding parameters such as welding current, electrode force(or squeeze force) and parts cleaning on the sound weld, and establishing the most reliable weld conditions for HWP(Heavy Water Reactor) fuel end capping with the resistance upset butt welding. Major results obtained are as follows. 1. The amount of sound weld was increased with increasing weld current(5.0-11KA) because the activated diffusion with increasing heat generation played an important role in eliminating the porosity and weld line in the weld interface. 2. It was found that weld current was not significantly influenced by the electrode force although the increase of it caused a slight increase of weld current and upset deformation. 3. Acetone rinsing before drying for the Zircaloy-4 end cap cleaning produced the reliable sound weld because it would remove the remaining solvent and surface films, and provided the uniform contact between the end cap and the tube. 4. The optimum welding conditions for fuel end capping by a resistance upset hytt welding are obtained as follows. weld current: 10-11KA, electrode force: 62-90KPa parts cleaning: vapor degreasing.rarw.water, acetone rinsing.rarw.drying.