• 제목/요약/키워드: Steel scrap

검색결과 64건 처리시간 0.025초

Geotechnical properties of tire-sand mixtures as backfill material for buried pipe installations

  • Terzi, Niyazi U.;Erenson, C.;Selcuk, Murat E.
    • Geomechanics and Engineering
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    • 제9권4호
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    • pp.447-464
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    • 2015
  • Millions of scrap tires are discarded annually in Turkey. The bulk of which are currently landfilled or stockpiled. These tires consume valuable landfill space or if improperly disposed, create a fire hazard and provide a prolific breeding ground for rats and mosquitoes. Used tires pose both a serious public and environmental health problem which means that economically feasible alternatives for scrap tire disposal must be found. Some of the current uses of scrap tires are tire-derived fuel, creating barrier reefs and as an asphalt additive in the form of crumb rubber. However, there is a much need for the development of additional uses for scrap tires. One development the creation of shreds from scrap tires that are coarse grained, free draining and have a low compacted density thus offering significant advantages for use as lightweight subgrade fill and backfill material. This paper reports a comprehensive laboratory study that was performed to evaluate the use of a shredded tire-sand mixture as a backfill material in trench conditions. A steel frame test tank with glass walls was created to replicate a classical trench section in field conditions. The results of the test demonstrated that shredded tires mixed with sand have a definite potential to be effectively used as backfill material for buried pipe installations.

Current Status of Magnesium Smelting and Recycling Technology (마그네슘의 제련 및 리사이클링 기술 현황)

  • Sohn, Ho-Sang
    • Resources Recycling
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    • 제29권5호
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    • pp.3-14
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    • 2020
  • Magnesium is the third most abundant structural metal after aluminum and iron. Magnesium is the lightest metal in the common metals. It has a density 33 % less than aluminum and 77% lower than steel. However, the primary magnesium production process is highly energy intensive. The recycling of magnesium scrap reduces the energy consumption and environmental burden, comparing to the primary metal production. However, the amount of recovered metal from scrap is limited because of the difficulties to remove the impurities in the scrap. This work provides an overview of the magnesium production and recycling process.

Environment Emission and Material Flow Analysis of Chromium in Korea

  • Shin, Dong-won;Kim, Jeong-gon
    • Journal of Powder Materials
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    • 제22권3호
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    • pp.187-196
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    • 2015
  • With the stabilization of Korea's industrialization, it has become interested in the efficient use of rare metals, climate change and industrial environment and safety etc. It is thus making efforts to implement economic policies that address such issues. Therefore it is necessary to understand the demand, supply and use of metal materials. Since 2010, the Korean government has developed the integrated material flow methodology and has been trying to examine the demand, supply and use of metal materials. In 2013, the Korean government surveyed the material flow of chromium. Material flow analysis and environment emission of chromium were investigated 8 steps; (1) raw material, (2) first process, (3) Intermediate product, (4) End product, (5) Use/accumulation, (6) Collection, (7) Recycling, (8) Disposal. Chromium was used for stainless steel, alloy steel, coated sheets, refractory material and coating materials. Recycling was done mainly in use of stainless steel scrap. To ensure efficient use of chromium, process improvement is required to reduce the scrap in the intermediate product stage. In the process of producing of the products using chromium, it was confirmed that chromium was exposed to the environment. It requires more attention and protection against environment emission of chromium.

Recent Improvements in Integrated Zinc Control and Dust/Sludge Recycling at China Steel

  • Liu, Kuo-chung;Chiang, Shyh-yi
    • Proceedings of the IEEK Conference
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    • 대한전자공학회 2001년도 The 6th International Symposium of East Asian Resources Recycling Technology
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    • pp.437-442
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    • 2001
  • In an integrated steel mill, zinc (Zn) inputs from raw materials and steel scrap are enriched in the dusts and sludges collected from gas and water cleaning systems. The reuse of these dusts and sludges must be controlled within certain limit to avoid Zn accumulation and related operational problems in blast furnace. An integrated system has been established at China Steel Corporation (CSC) to enhance the internal reuse of Zn-containing dust/sludge while keeping Zn input within control lim it. However. the performance of this system has not been very satisfactory until one and half years ago when a rationalization process was initiated. The essence of this rationalization process, the recent improvements in Zn control and dust and sludge reuse are reported and discussed.

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INFORMATION SYSTEM ON INTEGRATED RADIATION SAFETY (ISIRS) AND ORPHAN SOURCES CONTROL IN KOREA

  • Lee, Dewhey
    • Journal of Radiation Protection and Research
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    • 제26권3호
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    • pp.255-263
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    • 2001
  • An Orphan Sources Control program controlled by a web based information system in Korea has been developed to satisfy the national demand on a total management of and integrated radiation safety. There are, currently, three approaches going on to control and manage the orphan sources in Korea. First, Korean regulatory authority has been conducting scrutinizing investigation on and thoroughly monitoring the possession of unlicensed radioactive sources from the late 1990s. Second, the regulatory authority will fully operate an information system on radiation safety to effectively trace and monitor all radioactive sources in the country by the mid 2001. Finally, the regulatory authority strongly advises steel mill companies to closely scrutinize and inspect the scrap metals when they attempt to reutilize metals to prevent from being contaminated by uncontrolled sources through the scrap monitoring systems.

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