• Journal of Biosystems Engineering
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• 제40권1호
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• pp.61-66
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• 2015

Purpose: The purpose of this study was to establish conditions to dry a radish by examining the drying and quality characteristics depending on the air temperature and velocity of a far infrared conveyor dryer. Methods: A sample of weighing 6 kg was dried until the moisture content reached $15{\pm}0.5%$ (w.b.). Four temperatures (50, 60, 70, and $80^{\circ}C$) and three air velocity levels (0.4, 0.6, and 0.8 m/s) were employed as the drying factors. Results: The drying rate increased with the increase in the temperature and air velocity but decreased with time. However, the drying rate was influenced by temperature rather than velocity. At a temperature $50^{\circ}C$ with a air velocity of 0.4 m/s, it took 350 min for the radish to dry which was the longest drying time; $80^{\circ}C$ with a air velocity of 0.8m/s, it took 180 min for the radish to dry, which was the shortest drying time. ${\Delta}E$ (the color difference value) increased with the increase in temperature and air velocity. The browning and rehydration ratio increased as the temperature rose. Energy consumption decreased with the increased temperature and air velocity. Conclusions: Based on the results of this study, the best drying conditions for the radish were determined to be a temperature of $70^{\circ}C$ with an air velocity of 0.8 m/s.

• 한국식품영양과학회지
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• 제32권8호
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• pp.1297-1301
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• 2003

감귤의 건조에 따른 품질 특성을 모니터링하고 기호도가 우수한 건조 감귤을 제조하고자 건조온도 및 건조시간에 대한 중심합성실험 계획으로 반응표면분석을 실시하였다. 그 결과 수분활성도, 경도(hardness) 및 부드러움 정도(softness)는 건조온도에 영향을 많이 받는 것으로 나타났다. 건조 감귤의 건조온도가 증가할수록 수분 활성도는 감소하는 것으로 나타났으며, 경도는 증가하는 것으로 나타났다. 부드러움 정도는 건조 온도가 낮고 건조시간이 짧을수록 높게 나타났다. 건조감귤의 전반적인 기호도는 건조온도가 낮을수록 높은 기호도를 가지는 것으로 나타났다. 높은 기호도를 가지는 범위에서의 경도는 2.01 ∼ 3.20 ${\times}$ $10^{6}$ dyn/$\textrm{cm}^2$, 부드러움 정도는 62.54 ∼ 146.37 cm/kg의 범위로 나타났다. 이러한 범위를 만족시켜주는 건조 조건범위는 건조온도 66 ∼ 75$^{\circ}C$ 및 건조시간 8 ∼ 14 hr범위였다.

• Journal of the Korean Wood Science and Technology
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• 제25권2호
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• pp.67-74
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• 1997

A relationship between drying resistance and moisture content was found for 24, 27 and 30mm thick boards, and 45, 51 and 57mm thick dimensions of Japanese larch. Dahurian larch and radiata pine in order to modify the kiln schedule by using time schedules. The amount of drying resistance for Dahurian larch lumber was the highest, and radiata pine lumber was the lowest, on the basis of the same moisture content range. Drying resistance increased curvilinearly as moisture content decreased, and was higher for thicker lumber than for thinner lumber, at a given moisture content. Combined drying resistance for the three board thicknesses and the three dimension thicknesses showed a comparatively strong for radiata pine and a Japanese larch, while a weak correlation for Dahurian larch as a function of two independent variables, thickness and moisture content of lumber, respectively.

• 산업식품공학
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• 제15권3호
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• pp.262-268
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• 2011

The effects of pellet moisture content on physical properties (expansion ratio, density and breaking strength) of vacuum-puffed Yukwa (non-oil puffed Yukwa) were investigated in this study. The Yukwa was made from the waxy rice steeped at 25 and $30^{\circ}C$ for 3, 5 and 10 days with pellet drying times (6, 8 and 10.5 hr). As the drying time increased from 6 to 10.5 hr at $50^{\circ}C$, the highest value of pellet moisture content (29.4%) was found in the samples made from the steeped waxy rice at $25^{\circ}C$ for 5 days after 6 hr drying, while the lowest value (16.3%) was found at $25^{\circ}C$ for 3 days after 10.5 hr drying. Both redness and yellowness values of vacuum-puffed Yukwa increased as the drying time increased. The expansion ratio of Yukwa was greatly affected by drying time, ranging from 2.07 (26.8% pellet moisture content) to 7.01 (24.0% pellet moisture content). From the data, it can be concluded that the pellet moisture content had a significant influence on the physical characteristics of vacuum-puffed Yukwa. With vacuum puffing condition of 3 min heating and 2 min puffing, the pellets with about 25% moisture content showed higher expansion ratio, and lower density and breaking strength.

• 한국식품과학회지
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• 제42권2호
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• pp.147-154
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• 2010

열풍건조 온도를 달리한 생조기와 냉동조기의 내장의 유무에 따른 각각의 처리구별로 건조 온도를 달리하여(30, 35, $40^{\circ}C$) 건조기간 동안 화학적 품질 특성에 대해 알아보았다. 산도, pH, 염농도, 휘발성 염기질소, TBARS를 분석한 결과를 요약하면 다음과 같다. 일반적인 전통굴비의 염도는 22-23%정도를 나타내는데 본 연구에서 30, $35^{\circ}C$에서 건조하여 제조한 굴비의 염도는 17-20% 정도로 염도가 더 낮아 저염 굴비의 제조 가능성을 보였다. 또한 $35^{\circ}C$ 건조 처리구의 염도가 $40^{\circ}C$ 건조 처리구에 비해 2-4% 이상 낮은 염도를 나타내어 저염 굴비를 제조하는데 적합한 온도로 결정 할 수 있었다. VBN 함량에서는 30, 35, $40^{\circ}C$ 건조에서 유의적인 차이를 보이지는 않았으나 건조 시간이 경과함에 따라 VBN의 수치가 점차 증가하는 것을 볼 수 있었으며, 이는 굴비의 건조중 변패가 많이 일어난 것으로 여겨진다. 그 외 TBARS 함량 역시 건조기간이 경과할수록 점차 증가하는 경향을 보였으나 제품의 내장 유무에 대한 산패도 측정결과에서는 유의적인 차이는 없었다. 결론적으로, 전통적인 굴비 제조 방법에 비해 $35^{\circ}C$에서 15일 동안 건조 하는 것이 품질이 우수한 저염굴비를 빠르게 제조할 수 있을 것으로 생각되며 물리적 특성 및 관능적 특성에 대한 연구가 필요하다고 생각된다.

• 전기화학회지
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• 제27권1호
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• pp.40-46
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• 2024

리튬이온 전지의 전극제조 공정 중에서 건조공정은 생산속도 및 공정비용의 측면에서 매우 중요하다. 특히 전지의 에너지 밀도를 높이기 위하여 전극의 로딩레벨이 증가하게 됨에 따라 전극건조의 공정변수의 조정은 더욱 큰 주목을 받게 된다. 이에 본 연구에서는 양극에서의 건조온도를 다르게 하여 전극의 건조시간 및 그 성능에 대하여 비교하였다. LiNi_0.6Co_0.2Mn_0.2O₂ (NCM622)를 양극 활물질로 사용하고 2.5 및 4.5 mAh cm^-2의 로딩레벨에서, 건조온도는 120 ℃에서 210 ℃까지 다양한 건조온도 조건에서 제조되었다. 이와 같이 제조된 전극들의 물리적 및 전기화학적 특성을 비교하였다. 전극의 로딩레벨이 증가함에 따라 전극의 건조시간은 증가하였으나, 건조온도를 높이게 되면 시간을 줄일 수 있다. NCM622 양극의 제조 과정에서 사용된 건조 온도는 전극의 전기화학적 성능에 큰 영향을 미치지 않았으나, 210 ℃ 이상의 건조에서는 비저항의 증가 및 전기화학적 성능의 저하가 발생하였다. 이에 고로딩 전극의 제조에 있어 건조온도를 190 ℃까지 높여 성능의 손실없이 전극의 제조시간을 단축할 수 있다.

• Journal of Biosystems Engineering
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• 제4권2호
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• pp.32-45
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• 1979

The major objective of this study was to develope a computer simulation model to analyze drying process in a deep bed with natural air. The approach used to describe the continuous drying process in a deep bed was to divide the process into many small processes and simulate them by consecutively calculating the changes of grain and air conditions that occurred during short increment of time. Success criterion of the drying system was based on grain deterioration estimated by drymatter decomposition during drying. The results of the experimental test showed that the model satisfactory.

• 펄프종이기술
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• 제31권3호
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• pp.19-25
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• 1999

Effects of the process variable in Condebelt press drying including drying temperature, pressure , drying time, and moisture content of the sheets on the paper properties were examined. The experiment was performed with a static rig and Korean OCC was used as raw material. Significant improvement in sheet density, compression strength, tensile strength, surface smoothness ,etc. was obtained when condebelt drying was applied. Control of pressure and inlet dryness was found to be two most critical variables in improving sheet properties.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1990년도 가을 학술발표회 논문집
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• pp.131-134
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• 1990

Many papers have been published on drying shrinkage of hardened cement paste and cement mortar. The causes of drying shrinkage in cement mortar may be attributed to its mechanical properties, temperature, curing time and the evaporation of water from cement mortar. This paper deals only with drying shrinkage in cement mortar. In particular, the relationships between water evaporation and drying shrinkage are discussed.

• Asian-Australasian Journal of Animal Sciences
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• 제27권11호
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• pp.1615-1622
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• 2014

An accurate assessment of moisture content in feed ingredients is important because moisture influences the nutritional evaluation of feedstuffs. The objective of this study was to evaluate various methods for moisture content determination. In Exp. 1, the weight loss on drying (LOD) of corn, soybean meal (SBM), distillers dried grains with solubles (DDGS), whey permeate, whey powder, spray-dried porcine plasma (SDPP), fish meal, and a mixed diet of these 7 ingredients were measured by oven drying at $135^{\circ}C$ for 2 h. Additionally, the samples were dried at $105^{\circ}C$ for 3, 6, 9, 12, or 15 h. The LOD contents of the DDGS, whey permeate, and whey powder measured by drying at $135^{\circ}C$ for 2 h were greater than the values measured by drying at $105^{\circ}C$ for 3 h (p<0.05). All samples except SDPP (p = 0.70) dried at $105^{\circ}C$ for 6, 9, 12, or 15 h caused more LOD compared with the samples dried for at $105^{\circ}C$ for 3 h (p<0.05). The LOD contents of the individual ingredients were additive when dried at $105^{\circ}C$ regardless of drying time. In Exp. 2, moisture contents of corn, SBM, wheat, whey permeate, whey powder, lactose, and 2 sources of DDGS (DDGS1 and DDGS2) were measured by the Karl Fischer method, oven drying at $135^{\circ}C$ for 2 h, and oven drying at $125^{\circ}C$, $115^{\circ}C$, $105^{\circ}C$, or $95^{\circ}C$ for increasing drying time from 1 to 24 h. Drying samples at $135^{\circ}C$ for 2 h resulted in higher moisture content in whey permeate (7.5% vs 3.0%), whey powder (7.7% vs 3.8%), DDGS1 (11.4% vs 7.5%), and DDGS2 (13.1% vs 8.8%) compared with the Karl Fischer method (p<0.05). Whey permeate and whey powder were considerably darkened as the drying time increased. In conclusion, drying samples at $135^{\circ}C$ for 2 h is not appropriate for determining the moisture content in whey permeate, whey powder, or DDGS as well as the mixed diet containing these ingredients. The oven-drying method at $105^{\circ}C$ for 5 to 6 h appears to be appropriate for whey permeate and whey powder, and at $105^{\circ}C$ for 2 to 3 h for DDGS.