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Baek, Ko-Kil;Choi, Yang-Jin
- Journal of Korea Foundry Society
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- v.12 no.6
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- pp.471-479
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- 1992
For the last 2 decades, the bonding materials for the foundry sand and the foundry equipments with high performance have been developed and employed in the foundry shops. In those periods, the furan resins hardened in higher temperature have been replaced with the self-hardened ones in the room temperature. Simultaneously the various reclamation methods of the self-hardened furan resin sand have been developed in order to get the clean working environments, the reduction of solid wastes and the lower of production cost in the foundry. In this experimental study, the combustion reclamation method using the fluidized bed among the various methods was studied in order to reduce the L.O.I. and /or $N_2$ gas due to the deposition of the furan resins and the hardeners. Comparing the results of this experimental combustion reclamation method with those of the employed pneumatic method, the Surface Stability Index of the specimen made by combustion method is 30% higher than that of the latter one and L.O.I. decreases about 30%. The reclamation temperature of 650$^{\circ}C$ in this experimental fluidized bed would be recommended in the viewpoints of the reclamation period, the fuel consumption and the residual quantity of the furan resin. The formula determining the minimum fluidizing velocities according to the temperatures in the fluidized bed has been obtained.
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Kim, Kwang-Woo;Ko, Dong-Hyuk;Choi, Dong-Chon;Kim, Sung-Won;Kim, Joong-Yul
- International Journal of Highway Engineering
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- v.3 no.4 s.10
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- pp.105-116
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- 2001
This study was performed to evaluate the characteristics of waste foundry sand (WFS) and the asphalt mixture made of a foundry waste sand. To estimate the applicability of WFS, chemical and physical properties were measured by XRF(X-ray fluorescent), and SEM(Scanning electronic microfilm). To improve the stripping resistance of WFS asphalt mixture, anti-stripping agents (a hydrated lime and a liquid anti-stripping agent) were used. To improve tensile properties and durability of WFS asphalt concrete mixture, LDPE(low-density polyethylene) was used as an asphalt modifier Marshall mix design, indirect tensile strength, tensile strength ratio(TSR) after freezing and thawing, moisture susceptibility and wheel tracking tests were carried out to evaluate performance of WFS asphalt concrete. Comparing with conventional asphalt concrete, WFS asphalt concretes showed similar or the better qualify in mechanical properties, and satisfied all specification limits. Therefore, it Is concluded that waste foundry sand can be recycled as an asphalt pavement material.
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Hong, Yung-Myung;Lee, Yeong-Sang;Kim, Dong-Ok
- Journal of Korea Foundry Society
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- v.3 no.2
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- pp.100-105
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- 1983
The mechanism of coal-dust action on inhibiting burn-on of Sand to iron castings was taken in consideration by means of casting test and thermal decomposition test. To compare the ability of inhibiting sand burn-on, test castings were produced in green sand moulds added three different coal-rusts. And quantitative determination of lustrous carbon and volatiles production for coal-dust samples were performed.The lustrous carbon production was in good agreement with the casting test result. But total voltiles production was relatively inefficient on hibiting sand burn-on to test castings.The lustrous carbon theory can be given to explain the mechanism which coal-dust inhibits sand burn-on to iron castings.
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;Benson, Craig H
- Journal of the Korean Geotechnical Society
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- v.18 no.5
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- pp.179-193
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- 2002
Waste foundry sands were tested to determine their leaching characteristics when used as reactive media in permeable reactive barriers (PRBs). Water leach tests and column leach tests were performed on twelve foundry sands and three reference materials such as Peerless iron, a local fill material, and torpedo sand. The latter three materials were tested to compare concentrations of heavy metals and anions found in other materials commonly placed below the groundwater table with those from the foundry sands. Results of water leach tests md total elemental analyses showed that all of the laundry sands are Category 2 materials per Section NR 538 of the Wisconsin Administrator Code. However, tests on Peerless iron, torpedo sand, and a typical fill material indicate that these materials, which are commonly placed below the groundwater table, also are Category 2 materials. Thus, using foundry sand as a PR3 medium should pose no greater risk than that imposed using conventional construction materials.
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