• Title/Summary/Keyword: Chemical Process

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전기산화반응을 이용한 염색폐수 색도제거 공정 기술개발 (Development of Electro-Chemical process for dyeing wasetewater treatment)

  • 신동훈;최장승;조석진;이상헌;김순현;최성욱
    • 한국염색가공학회:학술대회논문집
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    • 한국염색가공학회 2008년도 제39차 학술발표회
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    • pp.117-118
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    • 2008
  • The main objectives of this study are develop an Electro-Chemical process for dyeing wastewater treatment. In this work, We are investigated to optimization of electro-chemical process condition such as pH, additives(NaCl), reaction time, current density. As a result, About 89% of color(influent 452.5 ptco. unit) was removed by Electro-Chemical process using type C $SnO_2$ electrode. This results are promising potential for dyeing wastewater treatment.

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화학기계적 연마 가공에서의 윤활 특성 해석 (Analysis of the Lubricational Characteristics for Chemical-Mechanical Polishing Process)

  • 박상신;조철호;안유민
    • Tribology and Lubricants
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    • 제15권1호
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    • pp.90-97
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    • 1999
  • Chemical-Mechanical Polishing (CMP) refers to a material removal process done by rubbing a work piece against a polishing pad under load in the presence of chemically active, abrasive containing slurry. CU process is a combination of chemical dissolution and mechanical action. The mechanical action of CMP involves tribology. The liquid slurry is trapped between the wafer (work piece) and pad (tooling) forming a lubricating film. For the first step to understand material removal rate of the CMP process, the lubricational analyses were done with commercial 100mm diameter silicon wafers to get nominal clearance of the slurry film, roll and pitch angle at the steady state. For this purpose, we calculate slurry pressure, resultant forces and moments at the steady state in the range of typical industrial polishing conditions.

생물난분해성 유기물질 함유 폐수처리를 위한 Fenton 산화법의 효율적 적용방안에 관한 연구 (A Study on the Efficient Applicability of Fenton Oxidation for the Wastewater Containing Non-biodegradable Organics)

  • 전세진;김미정
    • 상하수도학회지
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    • 제14권1호
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    • pp.76-83
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    • 2000
  • This research is about wastewater containing non-biodegradable TDI(Toluene Diisocyanate) that is treated by the activated carbon adsorption method. In the case of the Fenton oxidation process being applied to the existing process, optimal pH, reaction time, chemical dosing amount, removal rate, and cost were investigated. A pilot plant test was applied after finding optimal conditions with lab experiments. The optimal conditions were pH 3~5(COD removal rate 84~88%) and reaction time 30min~1hr. In higher $H_2O_2$ dosing amount, COD removal rate was a little higher. But there was little difference in the removal rate according to $FeSO_4{\cdot}7H_2O$ dosing amount. Treatment cost was economical in the case of the Fenton oxidation process being operated earlier than activated carbon adsorption system. But chemical dosing point, chemical mixing effect, chemical dosing amount, removal rate, and the cost of facility and others must be considered in practical process.

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Cu CMP 슬러리에서 화학첨가제 조건의 최적화 (Optimization of Condition of Chemical Additives in Cu CMP Slurry)

  • 김인표;김남훈;임종흔;김상용;김창일;장의구
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2003년도 하계학술대회 논문집 Vol.4 No.1
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    • pp.304-307
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    • 2003
  • Replacement of aluminum by copper for interconnections in the semiconductor industry has raised a number of important issues. The integration of copper interconnection can be carried out by CMP(chemical mechanical polishing) is used to planarize the surface topography. In this experiments, we evaluated the optimization of several conditions for chemical additives during Cu CMP process. It was presented that the main cause of grown particle size is tartaric acid. The particle size was in inverse propotion to a quantity of bead and the time of milling process. The slurry stabilizer and oxidizer have been shown to have very good effect by addition in later milling process.

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Cybernetic Modeling of Simultaneous Saccharification and Fermentation for Ethanol Production from Steam-Exploded Wood with Brettanomyces custersii

  • Shin Dong-Gyun;Yoo Ah-Rim;Kim Seung-Wook;Yang Dae-Ryook
    • Journal of Microbiology and Biotechnology
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    • 제16권9호
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    • pp.1355-1361
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    • 2006
  • The simultaneous saccharification and fermentation (SSF) process consists of concurrent enzymatic saccharification and fermentation. In the present cybernetic model, the saccharification process, which is based on the modified Michaelis-Menten kinetics and enzyme inhibition kinetics, was combined with the fermentation process, which is based on the Monod equation. The cybernetic modeling approach postulates that cells adapt to utilize the limited resources available to them in an optimal way. The cybernetic modeling was suitable for describing sequential growth on multiple substrates by Brettanomyces custersii, which is a glucose- and cellobiose-fermenting yeast. The proposed model was able to elucidate the SSF process in a systematic manner, and the performance was verified by previously published data.

Efficient Transformation of Klebsiella oxytoca by Electroporation

  • Ki Jun Jeong;Hyu
    • Biotechnology and Bioprocess Engineering:BBE
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    • 제3권1호
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    • pp.48-49
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    • 1998
  • A protocol for the transformation of Klebsiella oxytoca by electroporation was developed. Preparation of competent cells at early exponential phase was most critical to obtain high transformation efficiency. The highest efficiency of 1.6$\times$106 transformants per $\mu\textrm{g}$ DNA(pBR322) could be obtained by electroporation of K. oxytoca cells prepared at the OD600 of 0.2 with 1.25$\mu\textrm{g}$ DNA at the filed strength of 2.5kV, the parallel resistance of 200$\Omega$ and capacitance of 25$\mu$F.

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화학공정 안전성평가 기법에 관한 비교 연구 (A Comparative Study on Safely Analysis Methodology of Chemical Process)

  • 변윤섭;안대명;황규석
    • 한국안전학회지
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    • 제18권2호
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    • pp.64-72
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    • 2003
  • A new reliability assessment methodology is presented and the new method is compared with fault tree analysis. The system is modeled by directed graph at a new methodology, which is composed of nodes and arcs. The directed graph corresponds to the layout of chemical process and is easy to construct. Therefore, the directed graph analysis is applicable to the chemical process that has complex sequence. The example of fault tree analysis and directed graph analysis is given. The directed graph analysis has proved to be a valuable and useful method for the reliability assessment of chemical process.

The Effect of Light on Champagne Yeast Cell Growth and Ethanol Production Under Variable pH Conditions

  • Collins, Paul C.;Schnelle, Karl B.;Malaney, Jr.George W.;Tanner, Robert D.
    • KSBB Journal
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    • 제6권2호
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    • pp.189-194
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    • 1991
  • The effect of wtlitc light on unaeraten growth of Baker's yeast and the accompanying ethanol production has been studied in a batch process at 27$^{\circ}C$. Over the 80-hour period of the Champagne yeast process without pH control, the cull growth was inhibited by the fluorescent light. Another observed difference between the runs is that the drop and subsequent rise in redox potential occurred much sooner in the fermentation with light than in the fermentation without light. This preliminary study indicated that ethanol production could be enhanced by light as the cell concentration is repressed. The possible pathway, shift of the sugar substrate toward ethanol and away from cells was manifested by another difference as well. As observed under the microscope, many of the yeast cells grown under light budded without dividing by the normal fission process as they did in the dark. Furthermore, the undivided and branched (light grown) cell did not agglutinate at the end of the fermentation process as did the distinct spherical (dark grown) cells.

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