• 제목/요약/키워드: Chemical Industries

검색결과 864건 처리시간 0.054초

Memtrane SEparation of Activated Sludge for Waste Water Treatment and Water Recycle

  • Miyano, O-Tadadki;Yohgi Inoue;Toyozo Hamada;Shuji Nakatsuka
    • 한국막학회:학술대회논문집
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    • 한국막학회 1999년도 Energy Saving Membrane Separtion Systems 에너지 절약형 막분리 시스템
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    • pp.39-39
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    • 1999
  • Membrane separation technology has become a more attractive technology on waste water treatment and water recycle in recent years. On this application, membrane does not take main part of treatment, such as decomposition or handling of organic matter in the waste water, but it is very important supporting method in the total system. Activated sludge is most popular method as main part. In the system , membrane works as a separator to obtain clear water after biological treatment, by which the permeate could be released, recycled or applied to further additional treatment, instead of conventional sedimentation, coagulation and sand filtration. We would like to introduce our system cases for waste water treatment and water recycle, in which membrane separation technology works. In most of cases, membranes are applied to solid- liquid separation of activated sludge. Our experiences will be introduced as following items.

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가역 화학 열 펌프(CHP)를 이용한 냉장.냉동 시스템 개발 연구 (R&D OF FREEZING AND REFRIGERATION SYSTEM USING CHP.)

  • 이종호;김석종
    • 한국에너지공학회:학술대회논문집
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    • 한국에너지공학회 1996년도 춘계학술발표회 초록집
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    • pp.132-135
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    • 1996
  • This study is to develop an ammonia based chemical heat pump(STELF) for a freezing and refrigeration system coupled to gas, fuel and/or waste from industrial processes as heat sources. Recently it has been continually taking a growing interest in chemical heat pumps without electric power and having higher COP's than those of existing compression type refrigeration systems using freon. By introducing STELF technology, efficient heat recovery utilizing enormous amount of waste heat in energy consuming large scale industries or building for their own refrigeration purposes is possible. Moreover, air-conditioning systems coupled to city gas for small scale industries or building can be realized. Therefore, STELF technology can contribute much for overall energy savings and efficient energy management.

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Fabrication and Properties of Nano-structured Ceramics

  • Ueno, Tomoyuki;Yoshimura, Masashi
    • 한국분말야금학회:학술대회논문집
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    • 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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    • pp.321-322
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    • 2006
  • Nano-structured ceramics, which consist of structural elements with nanometer-size crystallites, are expected to show various unusual properties. We developed the novel nano-structured ceramics which consists of $Si_3N_4$ and TiN and a self-lubricant material. The ceramics was fabricated by powder metallurgy process using mechano-chemical grinding process and short-time sintering process. Each grain size of matrix and the self-lubricant particle was under about 50 nm and a few namometer. It showed high wear resistance and low friction coefficient by controlling of microstructure.

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아프리카에서 다국적기업의 윤리경영 (Ethical Issues of Multinational Companies in Africa: host country and industry characteristics)

  • 김재준
    • 무역학회지
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    • 제44권3호
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    • pp.271-287
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    • 2019
  • This paper reviews and analyzes the ethical issues of multinational corporations (MNCs) in Africa. First, we find that the transparency and institutions of a host country have a negative relationship with the number of ethical violations of the MNCs. Second, this covers the effects of industry characteristics on each category of ethical issues such as the human rights and the environment. Based on the database of "Ethical Consumer", we show that the Auto, Chemical, Finance, and Telecommunication industries are more likely to violate human rights issues, and that Mining, Oil, Cosmetics, and Chemical industries are more likely to pollute the environments. Further, the country of origin does matter: the US and Asian companies are more likely to be involved with the business ethics violations than are their European counterparts.

Study on the Causes of Premature Cracking of Epoxy Coatings for Ship's Ballast Tanks

  • Song, Eun Ha;Lee, Ho Il;Chung, Mong Kyu;Lee, Seong Kyun;Baek, Kwang Ki
    • Corrosion Science and Technology
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    • 제5권2호
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    • pp.69-76
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    • 2006
  • Premature cracking of the epoxy coatings applied on ship's ballast tanks(BT) can lead to damage of ship's hulls. To avoid this, it's important to have clear understanding of the underlying mechanism and primary factors of the coating crack. In this study, the efforts were made to clarify the integrated effects of main factors, i.e., initial coating shrinkage, thermally induced strain, steel-structural strain and the intrinsic coating flexibility at the initial and after aging, to the early cracking phenomena of epoxy coating in the ship's ballast tank. The coating crack is caused by combination of thermal stress, structural stress, and internal stresses which is closely related to chemical structures of the coatings. On the other hand, thermal stresses and dimensional stabilities would rarely play a major role in coating crack for ballast tank coatings with rather large flexibility. Crack resistance of the coatings at early stages can be estimated roughly by measuring internal stress, FT-IR and $T_g$ value of the coatings. A new screening test method was also proposed in this study, which can be possibly related to the long-term resistance of epoxy-based paints to cracking.

LPCVD로 제조된 다결정실리콘에 As를 주입한 시료의 비저항에 대한 온도의존성 연구 (Temperature Dependence of Resistivity in As Implanted LPCVD Polycrystalline Silicon Films)

  • 하형찬;김정태;고철기;천희곤;오계환
    • 한국재료학회지
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    • 제1권1호
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    • pp.23-28
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    • 1991
  • 저압 화학 증착법으로 증착된 다결정실리콘에 As를 이온주입하여 As농도와 $25~105^{\circ}C$ 범위의 측정온도에 따른 비저항의 변화를 조사하였다. 비저항이 최대가 되는 적정 As농도가 존재하였으며 이때 비저항의 온도의존성면에서 활성화에너지 값도 최대를 보였다. Passivation공정후 감소된 비저항이 $O_2$플라즈마 처리와 $N_2$ 분위기에서의 열처리에 의하여 회복되는 현상에 대하여 설명한다.

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화학 및 가스 공정산업에서 주요 공정제어 기술 (Major Control Techniques for Chemical and Gas Process Industries)

  • 유성진;이창준;이종민
    • 한국가스학회지
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    • 제15권1호
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    • pp.1-8
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    • 2011
  • 최근 석유 위주의 에너지원에서 가스나 신재생에너지와 같은 새로운 에너지원을 생산 혹은 이용하는 공정들에 대한 연구가 활발한 가운데 이러한 공정들의 상업화를 위해서는 조업 중 에너지 절감과 생산 단가의 경제성 확보가 필수적이며, 이를 위해서는 적합한 공정제어 기법의 도입이 필수적이라 할 수 있다. 본 논문에서는 지난 50여 년간 공정산업에 적용된 다양한 공정제어 기법 중 큰 기틀이 되는 몇몇 기술을 소개하고, 가스 관련 공정의 응용 예 및 앞으로 나아갈 방향에 대해 논하였다.