• 제목/요약/키워드: pre-drying

검색결과 152건 처리시간 0.021초

PC 펠렛의 마이크로웨이브 건조를 위한 에너지 효율 분석 (Analysis of Energy Consumption for Microwave Drying in PC Pellet)

  • 이현민;김재경;전의식
    • 반도체디스플레이기술학회지
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    • 제20권4호
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    • pp.44-48
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    • 2021
  • Semiconductor inspection equipment makes components using materials with insulating properties for functional inspection including current and voltage of semiconductor parts. A representative insulating material is plastic, and plastic is made of a component through an injection process using plastic pellet. When plastic pellets contain excessive moisture, problems such as performance degradation and product surface defects occur. To prevent this, pre-drying is essential, and the heat convective type is the most applied. However, the heat convective type has a problem of low consumption efficiency and a long drying time. Recently, many studies have been conducted on a drying method using microwaves due to high energy efficiency. In this paper, drying was performed using a microwave for drying PC pellets. Energy consumption and drying efficiency analyzed by set up an experimental apparatus of heat convective, microwave, and hybrid(heat convective + microwave) types. It was confirmed that energy consumption and drying efficiency were high when drying using microwaves, and it was confirmed that the hybrid method improved drying performance compared to the heat convective method. It is expected that the research results of this paper can be used as basic data for drying plastic pellets using microwave.

Development of Kiln Schedules to Eliminate the Development of Internal Checking in Radiata Pine Boards

  • Kang, Ho-Yang;Booker, R.E.
    • 한국가구학회지
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    • 제19권2호
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    • pp.116-123
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    • 2008
  • Kiln schedule development was based on two schedule phases, the first being to determine the maximum safe kiln temperature during the check prone initial stage of drying, with the second stage determining how to accelerate drying once the danger of checking had passed. This was achieved by using 38 mm thick boards which were pre-screened for susceptibility to internal checking, and then drying matched sample boards over a range of kiln temperatures. Research has shown that below 50% MC there is no further risk of internal checking. However, difference in drying rate due to board width and the increased occurrence of wet patches in wide boards means that it is essential to modify the basic schedule according to the maximum board width. A condition of 52/40 $^{\circ}C$ was selected for the checking-free initial kiln drying step and a 5-step kiln-schedule dried the boards from 109% to 8% MC for 72.5 hours without internal checking.

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Improvement of the Quality of Dried Wild Vegetables by Micro Oil Sprayed Thermal Air Technique

  • Yonghyun Kim;Yunmi Park;Chul-Woo Kim;Uk Lee;Hyun Ji Eo
    • 한국자원식물학회지
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    • 제35권6호
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    • pp.778-784
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    • 2022
  • Wild vegetables, such as Cirsium setidens, and Aster scaber, are commonly distributed as dried materials because the wild vegetables lose their freshness quickly after harvest and distribution. Dried wild vegetables require rehydration to use as a food ingredient, and the quality of rehydrated wild vegetables is affected by pre-drying and drying methods. Here, we introduce the newly developed pre-drying and drying method, termed "micro oil sprayed thermal air (MOTA) technique". The three wild vegetables processed by the MOTA technique showed improved rehydration rate and reduced time to achieve maximum rehydration rate. Color characteristics were also improved in C. setidens. These results indicate that the MOTA technique improves the overall quality of rehydrated wild vegetables. It is expected that our findings could enhance the marketability of dried wild vegetables by improving overall quality and reducing preparation time.

Iroko재(材)의 고주파진공건조성 및 물리적 성질 개선 (Improvement of a radio-frequency/vacuum drying ability and physical properties of Iroko Lumber)

  • 이남호;진영문
    • 한국가구학회지
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    • 제17권1호
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    • pp.33-46
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    • 2006
  • This study was carried out to investigate a radio-frequency/vacuum (RF/V) drying ability and physical properties of the green boards and the pre-kiln dried boards with 40 mm thickness, and the 70 mm-thick green board of Iroko (Milicia excelsa). The major results were summarized as follows; The drying time from initial moisture content (MC) of 110% to approximate 6% MC for a 40mm-thick green board was 192 hours, and about 200 hours for the 70 mm-thick green board, respectively and so the RF/V drying times were dramatically shortened compared to conventional kiln drying time. The case hardenings at the RF/V drying completion stage test were very negligible, thus represented almost no existence of the residual stress. The checks were very slightly formed on all of the boards during the RF/V drying test, but crook appeared quite severely. During the accelerating test, the water-resistant treated specimens had not experienced any signs of checking occurred, whereas the control boards had encountered very frequent occurrences of end checking and slight surface checking. There were no observations of warping and discoloring regardless of the treatment.

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Effects of Blanching Methods on Nutritional Properties and Physicochemical Characteristics of Hot-Air Dried Edible Insect Larvae

  • Jae Hoon Lee;Tae-Kyung Kim;Sun-Young Park;Min-Cheol Kang;Ji Yoon Cha;Min-Cheol Lim;Yun-Sang Choi
    • 한국축산식품학회지
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    • 제43권3호
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    • pp.428-440
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    • 2023
  • Global meat consumption is increasing worldwide, however, supply remains lacking. Several alternative protein sources, such as cultured meat, plant-based protein production, and edible insects, have been proposed to overcome this shortage. Interestingly, edible insects are characterized by superior digestive and absorptive qualities that make them the ideal replacement for traditional protein production. This study aims to further the processing ability of insect protein by investigating the effects of various pre-treatment methods, such as blanching (HB), roasting (HR), and superheated steam (HS), on the nutritional properties and physicochemical characteristics of proteins extracted from Hermetia illucens larvae. The drying rate, pH value, color analysis, amino and fatty acid profile, as well as bulk density, shear force, and rehydration ratios of the above pre-treatment methods, were explored. HS was found to have the highest drying rate and pH value analysis showed that HB and HS samples have significantly higher values compared to the other modalities. Raw edible insects had the highest value in the sum of essential amino acid (EAA) and EAA index when compared to EAAs. HB and HS showed significantly lower bulk density results, and HS showed the highest shear force and the highest value in rehydration ratio, regardless of immersion time. Therefore, taking the above results together, it was found that blanching and superheated steam blanching pre-treatment were the most effective methods to improve the processing properties of H. illucens after hot-air drying.

곡류의 유동층 건조에 관한 연구 (1) (Study on the Fluidized Bed Drying of Grains (1) - Fluidization charcteristics of Rough Rice -)

  • 허종화;서길덕
    • 대한설비공학회지:설비저널
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    • 제13권3호
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    • pp.168-182
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    • 1984
  • For the purpose of drying high moisture rough rice effectively, from the view point of pre-drying, some basic experiments of fluidized bed drying of rough rice were carried out. The minimum fluidization velocities $(U_{mf})$ for both rough rice and glass bead were analyzed to find out fluidizing characteristics. The main results obtained were as follows ; 1) Minimum fluidization velocity of rough rice and glass bead were 2.01m/s and 4.07m/s, respectively, when using the distributor with $16\%$ opening ratio. 2) $U_{mf}$ calculated by Shirai's empirical equation and that calculated by Wen's modified equation were inconsistent with experimental data, while $U_{mf}$ calculated by Ergun's equation was consistent with the experimental data. 3) The following equations, on the basis of Leva's equation, were obtained. $$C_{mf}=1.19\times10^{-4}(Re_p)^{-0.0318)\;(rough rice)$$ $$C_{mf}=1.02imes10^{-4}(Re_p)^{-0.0047)\;(glass bead)$$

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PEG처리 수침고목재의 조습건조 (Humidity-Controlled Drying of PEG-Treated Waterlogged Woods)

  • 이광희;김수철;박원규
    • 보존과학회지
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    • 제27권1호
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    • pp.91-100
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    • 2011
  • 본 연구에서는 열화된 소나무류를 대상으로 PEG 처리 후 조습건조시 적정 PEG농도, 습도 및 시간을 조사하고자 하였고, 조습건조과정 중 치수안정화 효과를 진공동결건조 및 자연건조한 것과 비교하였다. 조습건조에서 PEG의 농도가 높을수록 건조시간이 단축되었으며 치수안정성이 우수하였다. 저농도(40%, 50%) PEG 함침 후 조습건조는 치수안정화 효과가 적었고 목재표면 및 내부에 갈라짐이 발생하였으며 PEG의 분포가 불균일하였다. 고농도(60%, 70%) PEG 함침 후 조습건조를 하였을 때 목재의 표면은 흑화현상으로 인해 색은 어두워졌으나, 저농도(40%) PEG 함침 후 진공동결건조한 것과 비교하여 거의 동일한 치수안정화 효과를 나타내었다. 따라서 대형발굴수침고목재의 보존처리시 진공동결건조가 불가능할 경우 고농도 PEG(70%) 함침 후 조습건조하는 방법이 가능하고, 이때 건조습도와 건조시간을 충분히 고려해서 건조해야 함을 알 수 있었다.

Synthesis and Characterization of Cathode Materials for the Lithium Secondary Batteries by Spray Drying Method

  • Oh, Si-Hyoung;Jeong, Woon-Tae;Cho, Won-Il;Cho, Byung-Won
    • 전기화학회지
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    • 제8권1호
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    • pp.42-46
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    • 2005
  • It has been known that the synthesis of the cathode materials for the lithium rechargeable batteries by the sol-gel process has many advantages over the conventional solid-state method. It has been, however, a continuing issue that new additional steps should be introduced to commercialize this process. In this work, spray drying was introduced to the existing sol-gel process as a continuous mass production method of the pre-heat treatment precursor materials. The precursors of $LiCoO_2$ and $LiNi_{0.8}Co_{0.2}O_2$ were continuously produced through spray drying from the solution containing stoichiometric amount of lithium, cobalt, and nickel sources as well as a chelating agent. The process variables, such as pH of the starting solution, spray drying conditions, and calcination conditions were optimized. The XRD pattern for the synthesized material indicated a good crystallinity with a layered structure.

사삼병의 제조조건에 따른 품질특성 (Quality Characteristics of Sasambeong according to Processing Conditions)

  • 유선미;고윤아;황인국;황영;김진숙;박성진;최병곤;서상영
    • 한국식품영양학회지
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    • 제25권4호
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    • pp.1081-1085
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    • 2012
  • 본 연구에서는 수문사설에 수록된 '사삼병'의 제조법 및 기호성을 개선하기 위하여 전처리 조건과 튀김온도에 따른 품질특성을 비교 분석하였다. 거피한 더덕을 2 mm 두께로 펴고 찹쌀가루를 묻히고, 상온에서 0, 30 min간 예비건조한 후 $160^{\circ}C$에서 1 min, $180^{\circ}C$에서 40 sec간 각각 튀겼을 때, 예비 건조 시 조지방 함량 및 경도는 유의적으로 높았고, 튀김 온도에 따른 차이는 크게 나타나지 않았다. 예비건조 후 튀김 처리 시 예비건조 전에 비해 관능특성이 전반적으로 높게 평가되었다. 수침시간에 따른 사삼병의 조지방 함량 및 경도는 감소하는 경향을 보였고, 색도는 큰 차이를 보이지 않았으며, 외관, 색, 향미, 질감 및 전반적인 기호도 등의 관능특성도 유의적인 차이가 없는 것으로 나타났다. 이상의 결과로부터 30 min간 예비건조 후 $160^{\circ}C$에서 1 min간 튀김 처리 시 사삼병의 관능특성이 양호한 것으로 나타났다.

종자 전처리 및 환경조절이 삽주 종자 발아에 미치는 영향 (Effects of Seed Pretreatment and Environment Controls on Germination of Atractylodes japonica Seeds)

  • 전권석;송기선;윤준혁;김창환;김종진
    • 한국약용작물학회지
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    • 제21권5호
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    • pp.394-400
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    • 2013
  • This study was carried out in order to examine the germination characteristics of Atractylodes japonica seeds, and it was to develop the more efficient pre-treatment and production system of the seeds. Experiment was performed by two ways-temperature control (10, 15, 20, $25^{\circ}C$) and shading treatment (full sunlight, 35, 50, 75, 95% of full sunlight). Seed pre-treatment before the each experiment was carried out by temperature (with low temperature and wetting treatment (LTW) for 0, 15, 30, 45 and 60 days) and shading treatment (with drying at room temperature (DRT), drying at low temperature (DLT) and water soaking (WS) for 48 hours). Seeds of A. japonica were germinated well under temperature control (overall 85.3~100%), especially high temperature. And, the seeds pre-treated with LTW for 45 days germinated with a 100% success rate. Under the surveying shading treatment, the highest germination rate was 95.8% with DRT and overall 63.2~95.8%. Germination rate under seeds with WS was 63.2~7.8%. As a result of surveying the whole experiment, A. japonica seeds don't need to pre-treat cause of high germination, but if it is performed with LTW for a certain period of time, it would be more productive.