• 제어로봇시스템학회:학술대회논문집
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• 1997.10a
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• pp.8-10
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• 1997

In recent years, the metal industry has become increasingly aware of an unwanted component in metal scrap-radioactive material. Worldwide, there have 38 instances where radioactive sources were unintentionally smelted in the course of recycling metal scrap. In some cases contaminated metal consumer products were distributed internationally. U.S. mill that have smelted a radioactive source face costs resulting from decontamination, waste disposal, and lost profits that range from 7 to 23 million U.S. dollars for each case. Despite radiation monitoring system does not provide 100% protection, POSCO has developed the system for the first time in the steel industry of KOREA.

• Journal of Korea Foundry Society
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• v.41 no.2
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• pp.139-143
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• 2021

A type of titanium alloy, ferro-titanium, is the main material used to manufacture steel and stainless steel. Considering economic aspects, ferro-titanium ingots are intended to be manufactured using low-cost titanium scrap, and the best pretreatment process for removing impurities from recycled titanium scrap surfaces was studied here. Instead of ordinary acid or organic solvents, ecofriendly methods were researched and applied, and chip scrap materials were used. A high-quality ferro-titanium ingot was manufactured from titanium scrap after a pretreatment process was applied, and the impurities and properties were analyzed and compared with commercial material standards through a component analysis.

• Resources Recycling
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• v.28 no.2
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• pp.3-13
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• 2019

Aluminum is the most abundant metal and the second most plentiful metallic element in the earth's crust, after silicon. Aluminum is a light, conductive, and corrosion resistant metal with strong affinity for oxygen. However, the primary aluminum production process is highly energy intensive. The recycling of aluminum scrap reduces the energy consumption and environmental burden, comparing to the primary metal production. However, the amount of the recovered metal from scrap is limited because of the difficulties to remove the impurities in the scrap. This work provides an overview of the aluminum production and recycling process, from the preparation of alumina to the scrap upgrading and the melting process.

• Resources Recycling
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• v.29 no.5
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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.

• Proceedings of the IEEK Conference
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• 2001.10a
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• pp.209-212
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• 2001

Aircraft industry is developed very fast so titanium scrap was generated to manufacture. Titanium scrap was wasted and used to deoxidize cast iron so we are study recycling of it. In this research were studied that metal hydride of reacted in hydrogen chamber of AMS4900, 4901, return scrap titanium alloy and sponge titanium granule. The temperature of hydrogenation was 40$0^{\circ}C$ in the case of pure sponge titanium but return scrap titanium alloy were step reaction temperature at 40$0^{\circ}C$ and 50$0^{\circ}C$, and after the hydride of titanium alloy were crushed by ball mill for 5h. Titanium hydride contains to 4wt.% of hydrogen theoretically as theory. It was determined by heating and cooling curve in reaction chamber. The result of XRD was titanium hydride peak only that it was similar to pure titanium. Titanium hydride Powder particle size was about 45${\mu}{\textrm}{m}$, and recovery ratio was 95w% compared with scrap weight for a aluminum foam agent.

• Bulletin of the Korean Chemical Society
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• v.32 no.10
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• pp.3796-3798
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• 2011

• Resources Recycling
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• v.4 no.1
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• pp.25-30
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• 1995

In the preparatIon of reclaimed aluminium lllgot from alumimum scrap, the aluminium recovery was studied a as a function of the preliminary treatment of samples, addition of flux and melting atmosphere. AI dross is produced by an oxidation reaction at the surface of liquid metal. The recovery of AI metal increases u up to maximum 95% by adding salt up to 7%, The recovery of AI metal in the compacted chip bale without oil removal mcrease about 14% compared io non-compacted chip. In the case of the AI seed melting process, the recovery of Al metal of the crushed and compacted chip hale is 97%, In meltmg of alumimum scrap under the atmosphere of carbon and nitrogen gas, the recovery of AI metal increase, but it is decreased when the mixture of salt and carbon powder is added excessively.

• Transactions of the Korean Society of Mechanical Engineers
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• v.10 no.6
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• pp.923-928
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• 1986

A set of measurements has been made for the thermal conductivity of the pure paraffin in liquid and solid phases and for the effective thermal conductivity of the paraffin with metal scrap with the aid of the heat flux meter. Ther thermopile-type heat flux meter has been designed by steady state method and the functional relation between the temperature difference of both sides and heat flux has been obtained. The measured values of thermal conductivity are compared with the existing data for the pure paraffin and with the predicated values from the suggested model in which only one empirical constant is contained. The comparison within ten percent of the volume fraction of the metal scrap in the paraffin is satisfactory.

• Resources Recycling
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• v.4 no.3
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• pp.10-18
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• 1995

Recycling of GaAs scrap which occurs durmg the manufachre of GaAs waters is. therefore, required to solve the environmentalproblcrns caused by arsenic metal and to reutilize gallium which is a expensive metal. A thema-analyticalstudy (thermogravimeg. and derivative thermogravimetry) tor the evaporation behavior of Fa, As from Gak\ulcorner scrap powdersat vacuum atmosphere(2-2.5X 10'mmHg); was primarily performed to identi j the possibility of Ga extraction. Until79YC, the weight change of G d s porvder does not take place, at 800-970C range GaAs vaporizes as the GaAs compound,and over 1WO"C it decamposes mto Ga and As md then As vaporizes rapidly as a result of the difference af vaporprcssure for Ga and As, liquid Ga rcmains eventually.mains eventually.

• Journal of Korea Foundry Society
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• v.18 no.3
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• pp.240-245
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• 1998

In the view point of the environmental conservation and the energy reduction, the recycling of metal scrap is coming as one of the global subjects in the world. In this study, the movement of intermetallics with electromagnetic force in a melt of a scrap of Al-Si-Cu alloy (JIS ADC12), which was widely used in diecasting process, was investigated in order to eliminate the Fe element, which was usually accumulated in a scrap. In this study, we applied electromagnetic method to eliminate Fe element in ADC12 aluminum alloy scrap which contains 1.64wt.% Fe and the effects of electromagnetic force on the particle movement was visualized and confirmed by water modeling and experiment. As a result, the Fe intermetallic compounds are moved to the direction opposite to that of the electromagnetic force as the force applies, thus eliminated from the bulk metal. Therefore, the content of Fe in matrix decreased from 1.64wt.% to 0.45wt.%.