• Korean Journal of Food Science and Technology
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• v.41 no.2
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• pp.146-150
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• 2009

Sliced ginger samples were dried using 30, 50, and 80% maltodextrin, respectively, as a dehydrating agent. The moisture content of the maltodextrin-treated ginger decreased with increasing concentrations of maltodextrin. The dehydrated ginger was compared with hot air-dried and freeze-dried ginger samples in terms of rehydration ratio, gingerol content, color, and sensory characteristics. The rehydration ratio of the maltodextrin-treated ginger was superior to those of the hot-air dried or freeze-dried ginger. In addition, the maltodextrin-treated ginger had the highest content of 6-gingerol among the samples. Color as well as sensory scores for odor, texture, appearance, and overall acceptance were greater for the maltodextrin-treated ginger compared to the hot-air dried or freeze-dried ginger. These results indicate that drying ginger with maltodextrin is very efficient because good rehydration capacity is retained and minimal cell destruction can be achieved.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2000.11a
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• pp.54-54
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• 2000

종이의 생산성을 향상 시키기 위한 방법에는 초지기의 광폭화오} 생산 속도의 증가 가 있다. 현재 초지기는 10m까지 생산 폭이 확대 되었고, 생산 속도에 있어서는 최 신 설비의 경우 2,OOOm/min로 설계 되고 있다. 따라서 생산 폭과 속도의 증가는 이 전의 소폭과 저속의 생산 셜비에서와 동일한 원료 배합과 생산 관리로는 최적의 생 산 효율을 달성하는데 문제점이 있다. 그러므로 현재 각국의 신규 제지 설비에 적 용되 고 있는 twin wire system역 시 생 산 속도의 증가를 극복하고 기 존의 fourdrinier s system 이 지니고 있는 문제점을 극복하기 위해 도입되었다. 두 가지의 생산 설비에서 제조된 종이의 가장 큰 차이점은 미세 입자들의 분포와 종이의 구조적 특성에 있다. 특히 fourdrinier system에서 미세 입자들의 분포는 횡단 면을 기준으로 볼 때 표면에서 와이어 면으로 진행됨에 따라 급격히 감소된다는 것 을 알 수 있다. 이러한 사실은 주지하는 바와 같이 초지 형성부에서 효과적인 탈수 를 달성하기 위해 부착되어 있는 여러가지 탈수 장치들의 영향으로 와이어 방향으 로만 급격한 탈수가 일어나기 때문이다. 그러나 twin wire system 2.! gap former어$\mid$ 있 어서 미세 섬유와 충전제가 횡단면상에서 분포하는 형태는 "U"자 형태로 상면과 하 면에서 가장 높은 미세분의 분포를 나타내고 줄간층에는 상대적으로 낮은 미세분이 분포하고 있을을 알수 있다. 따라서 종이의 중간층 미세분 분포의 감소는 섬유간 표면적의 감소를 의미하고 이로 인하여 결합력이 약해진다는 것을 알 수 있다. 특 히 도공 원지로 사용되었을 경우 heat off-set 인쇄시 블리스터와 같은 문제점을 일 으키기도 한다. 앞서 언급한 바와 같이 종이의 제조 설비에 따라 제조되는 종이의 구조적 특성이 변하게 되므로 동일한 도공 공정에 적용 되었을 경우 이들로부터 제 조된 도공지의 특성에도 영향을 미칠것으로 예측된다. 따라서 본 연구에서는 두 가지 초지기의 형태에서 제조된 원지가 도공 작업성과 도공지의 특성에 미치는 영향에 대해 고찰코자 하였다.대해 고찰코자 하였다.

• Journal of the Korea Organic Resources Recycling Association
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• v.18 no.2
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• pp.62-70
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• 2010

A feasibility test for accelerating composting of sewage sludge irradiated with electron beam(3kGy) was investigated. Dried wood chip and leaves were used as a bulking agent and carbon source, respectively. The test variables included changes in temperature, organics and nutrients, and bioactivities from experimental and control composters. Results indicates that the temperature rose up to $60^{\circ}C$ within 1 day and maintained high temperature above $50^{\circ}C$ for more than 5 days in the irradiated sludge cake composter. It resulted in the fast degradation of organics during the initial 5 days, showing that approximately 70% of total amount of carbon degraded within 20 days was destroyed. It is likely that the composting of electron beam irradiated sludge cake is able to reduce it's maturing period significantly.

• Environmental engineer
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• s.175
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• pp.56-62
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• 2001

하수처리장의 농축-소화-탈수 등 전형적인 슬러지처리 공정에서 발생하는 소화조, 농축조 상징액 및 탈리여액 등의 반류수는 유량은 적으나 고농도로써 처리장의 전체 처리효율에 심각한 영향을 주는 것으로 알려져 있는데 외국에서는 이미 반류수의 농도를 감소시키며, 또한 발생된 반류수를 효과적으로 처리하기 위한 기술개발에 대한 광범위한 연구가 활발히 진행되고 있다. 이는 반류수 내 고농도의 질소를 제거하면 기존 처리장에서도 상당한 수준의질소 제거가 가능하다는 판단

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 2001.05a
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• pp.173-176
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• 2001

• Journal of Korean Society on Water Environment
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• v.32 no.5
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• pp.458-464
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• 2016

This study evaluated the dewatering efficiency of inorganic dehydrating agents that contain oyster shells. A filter press dehydrator was used for this study. The experiments were performed by the single injection of calcium-based chemicals, the single injection of oyster shells, and the mixed injection of oyster shells and calcium-based chemicals. The moisture content of the dewatered cake generated after dehydration confirmed that the best dewatering efficiency was found at the mixing ratios of CaCO₃ to sludge, oyster shell to sludge, and inorganic dehydrating agent to sludge of 3:1, 10:1, and 1.5:2.5:1, respectively. The moisture contents exhibited less than 58% when the injection mixing ratio of inorganic dehydrating agent to sludge was 1.5:2.5:1. From EPS, SEM, and EDX analysis, it was found that the calcium adsorbed on the sludge surface could reduce extracellular polymeric substances (EPSs) and enhanced the dewaterbility. Based on the above results, it is considered possible to apply inorganic dehydrating agents containing recycled oyster shells in sludge dewatering in order to reduce sludge.

• Journal of Hydrogen and New Energy
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• v.35 no.1
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• pp.105-113
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• 2024

The natural gas dehydration process plays a central role in liquefying LNG. This study proposes two natural gas dehydration process systems applicable to liquefied natural gas (LNG) liquefaction plants, and compares and analyzes energy optimization measures through simulation. The fuel gas from feed stream (FFF) case, which requires additional equipment for gas circulation, disadvantages are design capacity and increased energy. On the other hand, the end flash gas (EFG) case has advantages such as low initial investment costs and no need for compressors, but has downsides such as increased power energy and the use of gas with different components. According to the process simulation results, the required energy is 33.22 MW for the FFF case and 32.86 MW for the EFG case, confirming 1.1% energy savings per unit time in the EFG case. Therefore, in terms of design pressure, capacity, device configuration, and required energy, the EFG case is relatively advantageous. However, further research is needed on the impact of changes in the composition of regenerated gas on the liquefaction process and the fuel gas system.

• Journal of the Korea Society for Simulation
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• v.5 no.1
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• pp.43-50
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• 1996

2-propanol/acetone/hydrogen 반응계로 구성된 화학적 열펌프 시스템은 낮은 온도(82.5~$90^{\circ}C$)에서의 2-propanol의 탈수소화 반응과 높은 온도(약 $200^{\circ}C$ 부근)에서의 acetone의 수소화반응을 이용하여 열을 고품위화 시키는 장치이다. 본 연구에서는 이 시스템의 해석 및 설계를 목적으로 이 시스템에 대한 수치적인 모델들을 세우고 Sequential modular approach를 이용하여 시스템의 모사를 수행하였다. 또한 에너지 효율을 최대화하기 위하여 열펌프 시스템에서의 환류비의 영향을 규명하였다. 모사결과 이 시스템의 scale up을 위한 정량적인 정상상태 운전조건들을 구할수 있었으며 두 반응의 반응 전화율이 다르더라도 반응물의 유량의 차이를 통하여 두 반응열이 거의 같아지는 것을 알수 있었다. 아울러 주어진 운전조건에서 증류의 환류비는 최소환류비 근처의 최적값이 존재함을 알수 있었다.

• Korean Journal of Food Science and Technology
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• v.25 no.5
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• pp.468-474
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• 1993

A dehydrating sheet comprises polymeric water absorber. which are packed in a semipermeable cellophane film bag allowing selective permeation of water. This sheet dehydration is quite different from conventional drying method such as sun drying, hot-air blast drying and cold air blast drying in a sense that samples are dried without heat treatment. As a part of the studies to develope a new processing method for effective utilization of dark muscle fishes, the preparation of a good quality salted and semi-dried mackerel by the dehydrating sheet was attempted. The dehydration time for preparation of a salted and semi-dried mackerels containing approximately equal moisture content were revealed $180{\sim}510min$ in conventional drying method and $90{\sim}160min$ in this sheet dehydration, respectively. The moisture and histamine contents of those salted and semi-dried mackerels were $59.4{\sim}62.4%$ and $2.5{\sim}3.6 mg/100g$, respectively. The changes in peroxide value, fatty acid composition, brown pigment formation, myofibrillar protein solubility and Ca-ATPase activity during processing of the salted and semi-dried mackerel prepared by the sheet dehydration were more lower than those of products prepared by conventional drying methods. Therefore, these result showed that the quality of a salted and semi-dried mackerel prepared by the sheet dehydration was imperial to that of those products by conventional drying method.

• Journal of the Korea Organic Resources Recycling Association
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• v.25 no.1
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• pp.47-55
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• 2017

The technology for hydrothermal reaction of organic waste is one of the promising process to improve energy efficiency of biomass waste recycling system since moisture contents of treated biomass could be reduced at 40% or less than by dehydration processes. For these reasons, many parts of the world are interested in hydrothermal reaction of organic waste. In this paper, drying performances were evaluated with and without hydrothermal reaction of organic wastes which are sewage sludge and food wastes. For the hydrothermal reaction, organic wastes were treated at $200^{\circ}C$ for 1hr. Drying time of treated organic waste by hydrothermal reaction was reduced. In case of food waste drying at $100^{\circ}C$, drying time of treated wasted was reduced more 52.9% than non-treated. Hence, drying performances of sewage sludge and food wastes should be improved by hydrothermal reaction. Drying rates of treated wastes were considerably increased at preheat period of drying characteristic curve as followings; at $80^{\circ}C$ sludge as 148%, $100^{\circ}C$ sewage sludge as 151%, $80^{\circ}C$ food waste as 209%, $100^{\circ}C$ food waste as 366%. It means the surface area of treated wastes could be increased with destruction of cell membrane by hydrothermal reaction. However, the designer and operator of drying process should be careful, since enhanced drying rate cause the extension the decreasing drying period.