• Title/Summary/Keyword: Dry Process

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Properties of Fresh Concrete with Dry Bottom Ash Processed by Various Method (다양한 방법으로 가공한 건식공정 바텀애시를 사용한 콘크리트의 굳지 않은 상태에서의 특성)

  • Sun, Joung-Soo;Choi, Hong-Beom;Lee, Myeong-Jin;Yu, Jae-Seong;Kim, Jin-Man
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2014.05a
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    • pp.92-93
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    • 2014
  • This study was carried out to process the shape of dry bottom ash using the impact crusher and gravity crusher, which are identified as most effective in improving grain shape through the preceding research, and a comparison was made between concrete that utilized the processed dry bottom ash as aggregate and concrete containing dry bottom ash before processing to understand properties of the new concrete.

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Numerical analysis on the flow field and moisture contamination in a dry room (Dry Room내 기류 및 수분오염에 관한 수치적 연구)

  • Lee, Kwan-Soo;Lim, Kwang-Ok;Jung, Young-Sick
    • Proceedings of the KSME Conference
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    • 2000.04b
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    • pp.865-870
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    • 2000
  • The flow and the moisture contamination of the dry room in the manufacturing process of lithium ion battery are analyzed numerically by finite volume method. Standard ${\kappa}-{\varepsilon}$ turbulent model widely applied in predicting turbulent flow is adopted in this study. Moisture contamination and distribution are studied by assumption of two cases; one-point generation and uniform generation throughout the room. To evaluate ventilation efficiency on moisture contamination, scales of ventilation efficiency are introduced. From these analyses, moisture contamination is strongly dependent on the flow field and the radius of moisture contamination can be reduced by closing a part of outlets in a dry room.

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Study on dry reforming and partial oxidation of methane. (대기압 플라즈마를 이용한 메탄의 건식개질과 부분산화반응의 비교)

  • Hwang, Na-Kyung;Cha, Min-Suk;Lee, Dae-Hoon;Song, Young-Hoon
    • Proceedings of the KSME Conference
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    • 2008.11b
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    • pp.2892-2897
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    • 2008
  • Plasma techniques have been proposed to generate a hydrogen enrich gas to investigate a feasibility of plasma techniques on a fuel reforming, we considered a dry reforming and a partial oxidation with methane in the atmospheric pressure. For these experiments, we employed an arc jet plasma reactor. The effects of input power and oxidizer in each process were investigated by product analysis, including carbon monoxide, hydrogen, ethylene, propane, and acetylene as well as methane and carbon dioxide. In both processes, input electrical power activated the reactions significantly. The increased ratio of the carbon dioxide to methane in the dry reforming doesn't affect to a methane conversion, whereas increased ratio of oxidizer to methane in the partial oxidation was very effective for the reaction. Moreover, for a simultaneous treatment of methane and carbon dioxide, a feasibility of a dry reforming combined with partial oxidation also has been investigated.

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Development of Pre-treatment for Tin Recovery from Waste Resources (주석 함유 폐자원의 공정부산물 전처리 기술)

  • Jin, Y.H.;Jang, D.H.;Jung, H.C.;Lee, K.W.
    • Journal of Powder Materials
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    • v.21 no.2
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    • pp.142-146
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    • 2014
  • Fundamental experiences have been studied for development of pre-treatment process of Sn by-products such as solders. Dry and wet separation/recovery processes were considered by the differences of physical properties. The by-products, which are analyzed by solder metal and oxides. The metal and oxide were simply separated by dry ball-milling process for 12 hours, after that recovery metal powder might be reusable as lead or lead-free solders. In terms of wet separation process, samples were dissolved in $HNO_3+H_2O_2$ and the precipitation were analyzed by $SnO_2$. Overall efficiency of recovery might be increasing via developing simple pre-treatment process.

Environmentally Conscious High Speed Machining Characteristics of Aluminum Alloys(AC4C.1) (알루미늄 합금(AC4C.1)의 환경친화적 고속가공 특성)

  • Bae, Jung-Cheol;Hwang, In-Ok;Kang, Ik-Soo;Kim, Jung-Suk;Kang, Myung-Chang
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.3 no.1
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    • pp.22-27
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    • 2004
  • Recently, environmental pollution has become a significant problem in industry and many researchers have investigated in order to preserve the environment. Environmentally conscious machining and technology have more important position in machining process, because cutting fluid has bad influence on the environment in milling process. This research is the experimental study on high speed machining of aluminum alloys through environmentally conscious machining. In this study, the surface roughness and chip appearance was investigated in the machining of aluminum alloys by dry machining, using cutting fluid and oil mist.

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A Via-Hole Process for GaAs MMIC's using Two-Step Dry Etching (2단계 건식식각에 의한 GaAs Via-Hole 형성 공정)

  • 정문식;김흥락;이지은;김범만;강봉구
    • Journal of the Korean Institute of Telematics and Electronics A
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    • v.30A no.1
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    • pp.16-22
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    • 1993
  • A via-hole process for reproducible and reliable GaAs MMIC fabrication is described. The via-hole etching process consists of two step dry etching. During the first etching step a BC $I_{3}$/C $I_{2}$/Ar gas mixure is used to achieve high etch rate and small lateral etching. In the second etching step. CC $L_{2}$ $F_{2}$ gas is used to achieve selective etching of the GaAs substrate with respect to the front side metal layer. Via holes are formed from the backside of a 100$\mu$m thick GaAs substrate that has been evaporated initially with 500.angs. thick chromium and subsequently a 2000.angs. thick gold layer. The fabricated via holes are electroplated with gold (~20$\mu$m thick) to form via connections. The results show that established via-hole process is satisfactory for GaAs MMIC fabrication.

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Characteristics and Modeling Analysis of Entrained Flow Gasifiers (분류층 가스화기 특징 및 공정모사 분석)

  • Yoo, Jeongseok;Kim, Youseok;Paek, Minsu
    • New & Renewable Energy
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    • v.9 no.3
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    • pp.20-28
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    • 2013
  • The gasification process has developed to convert coal into the more useful energy and material since decades. Despite the numberous design of ones, entrained flow gasifier of the major companies has had an advantage on the market. Because it has a merit of full-scale and high performance plant. In this paper, the gasification technologies of GE energy, Phillips, Siemens and Shell have been reviewed to compare their characteristics and a high performance gasification process was suggested. And the simulation model of gasifiers using Aspen Plus offered the quantitative comparison data for difference designs. The simulation results revealed the poor performance of the slurry feed than dry design. The corresponding cold gas efficiency of 77% is much lower than the 80.3% for the dry feed cases. The exergy analysis of the difference syngas quenching system showed that chemical quenching is superior to another. The results of analysis recommend the two stage gasifier with dry multi-feeder as the energy effective design.

Influence of threshold value of computed tomography on the accuracy of 3-dimensional medical model (전산화단층 촬영상의 임계치가 3차원 의학모델 정확도에 미치는 영향에 대한 연구)

  • Lee Byeong-Do;Lee Wan
    • Imaging Science in Dentistry
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    • v.32 no.1
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    • pp.27-33
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    • 2002
  • Purpose: To evaluate the influence of threshold value of computed tomography on the accuracy of rapid prototyping (RP) medical model Material and Methods : CT datas of a human dry skull were transferred from CT scanner via compact disk to a personal computer (PC). 3-dimensional image reconstruction on PC by V-works/sup TM/ 3.0 (CyberMed. Inc.) software and RP models fabrication were followed. 2-RP models were produced by threshold value of 500 and 800 selected in surface rendering process. Linear measurements between arbitrary 12 anatomical landmarks on dry skull, 3-D image model, and 2-RP models were done and compared. Thus, the accuracy of 500 RP and 800RP models was respectively evaluated. Results: There was mean difference (% difference) in absolute value of 2.27 mm (2.73%) between linear measurements of dry skull and 500 RP model. There was mean difference (% difference) in absolute value of 1.94 mm (2.52%) between linear measurements of dry skull and 800 RP model. Conclusion: Slight difference of threshold value in rendering process of 3-D modelling made a influence on the accuracy of RP medical model.

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A Study on the Soil-Redeposition in Drycleaning Process (드라이클리닝시의 재오염에 관한 연구)

  • Cha Ok Seon;Kang In Suk
    • Journal of the Korean Society of Clothing and Textiles
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    • v.12 no.3 s.28
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    • pp.383-390
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    • 1988
  • To investigate the soil-redeposition and color change on dry-cleaning, the white and, dyed, fabrics of cotton, silk, polyester and viscose rayon were put into ordinary commercial dry-cleaning machine with soiled cloths. The solvents used were hydrocarben, perchloroethylene and fluorocarbon. From the result, we obtained the following conclusions by examining soil-redeposition, color difference of fabrics and tenacity of cotton fabric. 1. In case of white fabrics, as a whole, perchloroethylene shows the lowest soil redeposition. When distillation process is adopted, the rate of soil redeposition is lowered. with hydrocarbon sdvent. The order of soil redeposition rate of fibers are following; cotton> viscose rayon> silk> polyester. 2. In case of dyed fabrics, the color difference between soil redeposited fabrics and originals ($\delta\;E_1$) is similar with white fabrics in pattern, and the order is cotton, viscose rayon, silk and polyester. The color difference between fabrics, treated by pure solvents and originals ($\delta\;E_2$ ) is also validated as a little. It seems to be due to the bleeding of dyestuffs from fabrics. 3. There is a little change of tenacity of cotton fabrics by dry-cleaning with perchloroethylene solvent. It is supposed that the damage is more influenced the repetitive mechanical action during dry-cleaning than by acidity of the solvent having the acid value of 0,14.

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Microstructural Characteristics of Ni/YSZ Cermet for High Temperature Electrolysis by Mechanical Alloying (기계적 합금화법으로 제조된 고온 수전해용 Ni/YSZ 전극의 미세구조 특성)

  • Park Keun-Man;Chae Ui-Seok;Hong Hyun Seon;Choo Soo-Tae
    • Korean Journal of Materials Research
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    • v.14 no.10
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    • pp.743-748
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    • 2004
  • Modified Ni/YSZ cermets for high temperature electrolysis were synthesized by the direct ball milling of Ni and YSZ powder. The ball milling was carried out in dry process and in ethanol with varying milling time. While the dry-milling decreased the average size from 65 to $80{\mu}m$, the wet-milling decreased the average size down to $10{\mu}m$. In addition, very fine particles less than $0.1{\mu}m$ were observed in the wet-milling condition. The subsequent process of cold-pressing and sintering at $900^{\circ}C$ for 2 h did not affect the particle size of dry-milled powder. The electrical conductivity of the dry-milled Ni/YSZ cermet showed the value of $5{\times}10^{2}\;S/cm$ and this value was increased to $1.4{\times}10^{4}\;S/cm$ after the sintering at $900^{\circ}C$ for 2 h.