• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회B
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• pp.2262-2267
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• 2008

In this paper, drying mechanism is analyzed for improving the energy efficiency of an electric clothes dryer which consumes more electric power than other appliances. For the purpose, characteristic curves of the dryer such as temperature, relative humidity, evaporation rate, mass transfer coefficient, remaining moisture content curves are experimentally obtained. Based on the experimental results and analysis of drying mechanism, the effect of power of a heater and heat loss on the power consumption of an electric clothes dryer are systematically presented. These results demonstrate the feasibility of controlling heat loss at the heater as well as backduct component to decrease the power consumption of an electric clothes dryer.

• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2018년도 춘계학술논문요약집
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• pp.76-77
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• 2018

• Food Science and Biotechnology
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• 제16권5호
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• pp.771-777
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• 2007

Sliced and whole root of rehmannia were dehydrated in a laboratory dryer at 40, 60, 80, and $100^{\circ}C$ to evaluate the kinetic parameters for dehydration of rehmannia. The drying curves of both samples were characterized by a falling-rate drying period only. Sliced rehmannia dried 1.1 to 3.1 times faster than whole root of rehmannia depending on drying temperature. Equilibrium moisture content (EMC) of rehmannia samples at the drying temperature tested were 0.069-0.078 g water/g dry solid, which was coincided with the monolayer moisture content (0.06 and 0.07 g water/g dry solid) evaluated from desorption isotherms using GAB (Guggenheim-Anderson-de Boer) model. A logarithmic model for thin layer drying was applied to evaluate the drying time to reach EMC ($t_{EMC}$) and drying constant (k). The effect of temperature on $1/t_{EMC}$ and k was described by the Arrhenius model with activation energy values of 32.56 and 47.14 kJ/mol determined using the former parameter, and 34.27 and 38.26 kJ/mol determined using the latter parameter for sliced and whole root of rehmannia, respectively.

• 한국정밀공학회지
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• 제31권6호
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• pp.505-511
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• 2014

In this paper, silver pastes were printed on polyethylene terephthalate (PET) film using screen printing and evaluated the drying characteristics by using dry oven and NIR drying system. The printed Ag films were dried at $140^{\circ}C$ and the drying time was changed from 10 to 90 seconds. To evaluate the electrical properties of printed Ag film, sheet resistance was compared. The sheet resistance of the dried thin silver film by using NIR drying system more rapidly decreased. To clarify this phenomena, the morphology and component of the dried surfaces were measured by using the scanning electron microscope (SEM) and the energy dispersive X-ray Spectroscopy (EDX), respectively. In the EDX measurement results, the oxidation of the surface was observed in the dried thin film by using the dry oven. The NIR drying system is more applicable than conventional hot air drying to apply continuous printing system.

• 설비공학논문집
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• 제26권9호
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• pp.441-446
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• 2014

In Jeju province, the Citrus is widely spread crop which is the most popular fruit on the island. When the quality of a Citrus is not in a good condition or when its size exceeds or is lower than the set criteria, it is discarded as a waste. In this study, a drying machine for waste Citrus has been developed with 2.6 GHz microwave energy supply to the Citrus at vacuum environment. The vacuum environment of the drying chamber was maintained to reduce the energy supply to the Citrus by lowering the evaporating temperature of the water. The experiment was conducted with variation of the vacuum pressure, interior temperature of the drying chamber, and operating time of the microwave. As a result, the effect of the temperature was shown to be higher than the other two control methods, and it showed with 0.305 g/W evaporation efficiency.

• 청정기술
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• 제24권2호
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• pp.119-126
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• 2018

This study introduced a treatment process that was developed to treat Indonesian low-rank coal with high-ash content, which has the same characteristics as residual coal from the biosolubilization process. The treatment process includes separation of ash, solid-liquid separation, pelletizing, and drying. To reduce the ash content, flotation was performed using 4-methyl-2-pentanol (MIBC) as frother, and kerosene, waste oil, and cashew nut shell liquid (CNSL) as collectors. The increasing amount of collector had an effect on combustible coal recovery and ash reduction. After flotation, a filter press, extruder, and an oven drier were used to make a dried coal pellet. Then another coal pellet was made using asphalt as a binder. The compressive strength and friability of the coal pellets were tested and compared.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 추계학술대회논문집B
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• pp.752-757
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• 2001

The characteristics of heat energy distribution on the fire-proof clay with microwave heating drying are numerically investigated using finite element method. The modelled regular hexahedron chamber$(50cm\times50cm\times50cm)$ filled with air consists of vertical heat source and sink walls, a fire-proof clay model, and adiabatic plates on the top and bottom walls. With different geometrical aspect ratios of the fire-proof clay model, the heat energy distribution is throughly investigated. The model gave a good prediction of the microwave heating characteristics of fire-proof clay. The optimal shape of the fire-proof clay for given chamber geometry and microwave power is analyzed.

• 한국축산시설환경학회지
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• 제8권3호
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• pp.177-182
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• 2002

녹용의 상품화를 위해서는 건조과정이 필요하다. 지금까지의 인공건조는 사육농가 스스로의 경험에 의한 건조가 대부분으로 이는 건조시설 및 건조방법의 미흡으로 비효율적이며, 건조 중 변질되거나 먼지, 세균 등에 오염되기 쉽다. 최근 선진국에서는 농산물의 고품질건조를 위한 다양한 건조방법들이 실용화되고 있으며 마이크로파를 이용한 건조방법도 그 중의 하나이다. 이러한 점에 착안한 본 연구에서는 우리가정에 널리 보급되어 있는 전자레인지를 이용한 녹용의 건조 가능성 여부를 검토하였으며 그 결과는 다음과 같다. 1. 녹용의 각질화 여부가 건조시간에 많은 영향을 끼치는 것으로 나타나, 건조시간과 건조소요에너지를 줄이기 위해서는 녹용을 부위별로 절편하여 건조시키는 것이 효과적인 것으로 나타났다. 2. 같은 건조시간에서도 템퍼링 시간의 길고 짧음에 따라 건조속도가 다르게 나타났으며, 각질화 진행 정도에 따라 템퍼링 시간의 조절이 필요한 것으로 판단된다. 3. 전자레인지를 이용한 녹용의 건조는 2분 건조 후 3분 템퍼링을 반복하는 것이 효과적인 것으로 나타났다. 4 본 실험결과 전자레인지의 마이크로파를 이용한 건조기술을 녹용 건조에 이용할 수 있을 것으로 생각된다. 5. 본 연구에서는 건조시간과 템퍼링 시간에 따른 건조만을 검토하였으나, 앞으로의 연구는 건조 후의 녹용의 성분변화 여부에 대한 검토가 필요한 것으로 사료된다.

• 에너지공학
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• 제18권4호
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• pp.213-220
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• 2009

수분의 함량이 높은 저품위탄을 건조시키기 위하여 유중 건조 방법에 대해 조사하였다. 최적의 건조 조건을 선정하기 위하여 최종온도, 석탄과 등유의 혼합비율, 석탄 또는 등유의 양, 혼합물의총량, 교반방법에 따른 석탄의 건조 특성을 관찰하였다. 최종온도가 $120^{\circ}C$ 이하일 때는 완전한 증발이 이루어지지 않았으며, $130^{\circ}C$ 이상인 경우에는 수분의 증발량에 큰 차이가 나타나지 않았다. 석탄과 등유의 혼합비율에서 석탄의 양이 증가 할수록 수분의 증발이 잘 이루어짐에 따라, 열에너지의 전달이 수분의 증발에 미치는 영향보다 증발한 수분이 등유 속에서 배출되기 위하여 필요한 에너지가 더 큰 것으로 나타났다. 혼합물의 총량이 많은 경우에는 건조후의 수분 함량이 더 낮아지지만 많은 시간이 소모되는 반면, 적은 경우에는 수분 함량을 일정한 수준 이하로 낮추기 어려운 반면에 짧은 시간에 일정한 함량까지 수분을 증발시킬 수 있는 것으로 나타났다. 따라서 등유와 석탄 혼합물의 유동성이 확보되는 한도 내에서 등유의 양을 가능한 줄이는 것이 석탄의 건조에 유리한 것으로 판단되었다. 한편, 질소를 이용한 교반과 진공을 개별적으로 적용한 경우에는 증발량이 향상되었다.

• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2017년도 추계학술논문요약집
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• pp.275-276
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• 2017