A Study on Recycling Process of Salt Flux from Aluminum Black Dross

( Byoungyong Im ),( Yubin Kang ),( Chan Gi Lee ),( Tae Hyung Kim ),( Hyun-woo Shim ),( Dae Guen Kim ) 한국폐기물자원순환학회(구 한국폐기물학회) 2019 ISSE 초록집 Vol.2019 No.-

Casting process is of important manufacturing routes for aluminum products that are used in the various industrial fields such as automobiles, electronics, and constructions. In this process, magnesium (Mg), which has the high oxidizing properties, is added as alloying element and thus some oxides can be caused. In order to obtain the enhanced recovery rate and purity of aluminum, it is essential to control the amount of oxides and inclusions (i.e., dross) during the melting process. Salt flux is put into the molten metal to prevent the generation of oxides and trap inclusions. At this time, substance generated at the surface of the molten metal is called black dross. In Korea, about 300,000 tons of aluminum dross are generated annually and about 60,000 tons are landfilled. In particular, the black dross generated from the recycling of aluminum cans is about 20,000 tons. However, the landfilled black dross contains a large amount of resources such as metals, oxides and salt fluxes, which are necessary to recycle. Herein, we report a separation and recovery of the salt flux from black dross. The used black dross is a spherical shape with approximately 2 cm in diameter and contains not only 50 wt.% of metals and oxides such as Mg, Al, MgO and Al2O3, but also 50 wt.% of flux such as NaCl and KCl. For separation and recovery of metals, oxides and salt flux, the black dross was treated along with a pulverization, dissolution, solid-liquid separation, and distillation techniques. Experiments were carried out to find the optimum conditions for each technique. The components were evaluated by ICP (Inductively Coupled Plasma), XRF (X-ray Fluorescence) and XRD (X-ray Diffraction and Scattering) analysis, and water content was determined by TGA (Thermogravimetric analysis). Black dross pulverized by cut mill is suitable in dissolution and solid-liquid separation (filter press), because the efficiency depends on a particle size. Furthermore, the distillation rate was the highest value at pressure (-0.04 MPa) and temperature (80 oC). When applied above, we can confirm that the recovery rate of salt flux from black dross is to be 97.99%.

Synthesis of Na-P1 and Analcime-typed Zeolite from Waste Resources

( Yubin Kang ),( Byoungyong Im ),( Jin-ho Yoon ),( Tae Hyung Kim ),( Hyun-woo Shim ),( Basudev Swain ),( Chan Gi Lee ),( Dae Guen Kim ) 한국폐기물자원순환학회(구 한국폐기물학회) 2019 ISSE 초록집 Vol.2019 No.-

Zeolite is a functional ceramic material having a versatile physiochemical properties and thus has attracted great interest as one of the most classes of environmental fields, for example catalyst, adsorbent and ion exchanger. In recent, it has been known that zeolite has an excellent effect on dehumidification and odor removal. Zeolites are theoretically known to have millions of crystal structures and generally exist in the form of aluminum and silicon polymerized with hydroxyl groups. Therefore, if some waste resources contain aluminum or silicon, they can be considered as candidates of a raw material for synthesis of zeolite. However, the preparation of zeolite along with waste resources is still challenging. In this study, Na-P1 zeolite and analcime-typed zeolite, which are mainly used as heavy metal ion exchangers, were synthesized using waste resources. The aluminum black dross (Al resource) and waste glass powder (Si resource) were used as raw materials of waste resources, which can be generated from the aluminum melting process and the waste LCD panel, respectively. To remove impurities of both raw materials, the acid treatment was carried out with 1 M hydrochloric acid for 2 hrs, and then were pulverized by oscillation mill. The obtained powder was used as a raw material for zeolite synthesis. Here, we applied to hydrothermal process for zeolite synthesis. With control of experimental parameters such as raw material ratio (aluminum black dross : waste glass powder), reaction temperature, and reaction time, it was confirmed that Na-P1 zeolite and analcime-typed zeolite were synthesized and optimum condition for selective synthesis of zeolite was also suggested.

폐 갈분을 이용한 친환경 합성목재 성형을 위한 원료 배합 기술 개발 및 특성 평가

임병용(Byoungyong Im),이찬기(Chan Gi Lee),박경수(Kyung-Soo Park),유희룡(Hee Lyong Ryu),강이승(Leeseung Kang) 한국에너지기후변화학회 2016 에너지기후변화학회지 Vol.11 No.2

Wood plastic composite (WPC) has attracted increasing research attention because they can be substitute for the materials in various residential construction industry and furniture industry due to the environmentally friendly and economical feasibility. In this work, ecofriendly WPC was developed using waste reed flour prepared by melt-mixing and compression molding. Effect of compatibilizer contents, mixing ratio of polymer metrics for WPC was investigated by measuring mechanical properties, morphology and water absorption. The mixing ratio of 1:3 for LDPE:Homo PP with 6-7 wt% compatibilizer has high strength and good moldability because of low porosity in WPC body and good dispersity of reed flour in polymer metrics.

Isolation of α-Glucosidase Inhibitor Producing Soil Microorganism and Inhibitory Effects of Microbial Metabolites on α-Glucosidase

Ha NamJool,Kim KyoungJe,Kang ByoungYong,Choi SungSook,Lee JinWoo 大韓藥學會 2002 大韓藥學會 總會 및 學術大會 Vol.2002 No.2

Effect of Joule-Heating Treatment on the Microstructure and Physical Properties of 16-Stranded Compressed Copper Wires

Jin-Ju Choi,Byoungyong Im,Yubin Kang,Dae-Geun Kim 대한금속·재료학회 2021 대한금속·재료학회지 Vol.59 No.11

Compressed wires are produced by cross-sectionally compressing stranded conductors, which results in a smaller conductor diameter. This also leads to a lower weight wire, because a thinner external insulated coating can be used, compared to the low-voltage wires typically used in automobiles. However, a post production heat treatment of the compressed wires is required because plastic deformation occurs during compression after drawing the wires. In this study, the work hardening of stranded compressed copper wires was controlled by Joule-heating, and the resulting changes in microstructure, mechanical, and electrical properties after various annealing voltages (0, 25, 27, 31, 35, and 39 V) were observed. The results confirmed that as the annealing voltage increased from 0 to 31 V, the anisotropic deformation texture with a <111> orientation as the main component was reduced, and micrograins were generated throughout the stranded wires via recrystallization. At an annealing voltage above 31 V, the grains grew to be more than twice as large as those before heat treatment. At an annealing voltage of 31 V these structural changes contribute to the elongation increase of the compressed wires to 28.34%, and an improvement in electrical resistance to 145.85 mΩ.

A Research on Synthesizing Lithium Hydroxide Nanoparticles using Recovered Lithium Carbonate from Battery Spent by Double Precipitation Method

( Tae Hyung Kim ),( Byoungyong Im ),( Yubin Kang ),( Chan Gi Lee ),( Hyun-woo Shim ),( Dae-guen Kim ) 한국폐기물자원순환학회(구 한국폐기물학회) 2019 ISSE 초록집 Vol.2019 No.-

High-purity Lithium hydroxide (LiOH) is used in many areas such as catalysts, carbon dioxide absorber and especially as lithium ion batteries. Various methods have been studied to synthesize LiOH, among those, ion exchange and electrolysis methods are commonly used. However, precursor conversion efficiency into LiOH using lithium carbonate (Li₂CO₃) is somewhat as low as under 60% due to its low solubility of Li₂CO₃ in water as reported in papers, showed mixed phase with Li₂CO₃ and LiOH coexisting in one solution. Due to its low solubility and conversion efficiency, even the precursor ratio precisely controlled, Li₂CO₃ powders still remained. To overcome these problems, double precipitation method has been adopted. Specific ratio of precursor, which is 1 : 2 was chosen and the hydroxyl containing precursor was divided into half. First precursor ratio of 1 : 1 was reacted for 90 min at solution temperature of 90oC and filtered to removed precipitates. After the filtration, half of its hydroxyl precursor was put into filtered solution and reacted with equal condition. After double reaction, precipitated powder was filtered and the solution was evaporated at solution temperature of 80℃ until the white powder emerged. Through this method, we could synthesize powder with pure LiOH-H₂O phase, 20 ~ 100 nm sized particles and 99.18% Li purity.

알루미늄 블랙드로스로부터 유가자원 회수를 위한 재활용 공정 연구

강유빈,임병용,김대근,이찬기,안병두,김용환,이만승,Kang, Yubin,Im, Byoungyong,Kim, Dae-Guen,Lee, Chan Gi,Ahn, Byung-Doo,Kim, Yong Hwan,Lee, Man Seung 한국자원리싸이클링학회 2018 資源 리싸이클링 Vol.27 No.5

알루미늄 드로스는 알루미늄 용해 공정에서 용탕 표면에 발생하는 산화물 덩어리로서, Salt 유무에 따라 화이트드로스와 블랙드로스로 구분된다. 화이트드로스의 경우 금속 함량이 높아 용해 공정으로 재활용 되지만, 블랙드로스는 금속 함량이 낮고 성분 분리가 어려워 대부분 매립 처리되며, 물과 반응하면 가스와 발열 반응이 일어나 토양오염의 원인으로 작용한다. 하지만 블랙드로스에는 NaCl과 KCl과 같은 Salt 성분과, $Al_2O_3$, MgO와 같은 무기소재가 포함되어 있어 이러한 유가자원을 회수하고 소재화하는 기술 연구가 필요하다. 본 연구에서는 알루미늄 블랙드로스를 재활용하기 위한 공정을 제시하였다. 파쇄-용해(Dissolution)-고액분리-감압증발을 거치는 공정을 통하여 블랙드로스에 존재하는 무기물과 용해성 물질을 분리하였다. 물과 블랙드로스 함량을 제어하여 조건에 따라 분리물의 회수율을 최적화하였으며, 블랙드로스:물 비율이 1:9 일 때 91 wt.%의 Salt flux 회수율을 보임을 확인하였다. 추가적으로, 회수된 무기물을 이용한 제올라이트의 합성을 통하여 블랙드로스의 소재화 가능성을 확인하였다.

Sm 첨가에 따른 Al-Si-Cu 알루미늄 합금의 미세조직 및 열전도도 변화

최진주,강유빈,임병용,이찬기,김한구,박광훈,김대근,Choi, Jin-Ju,Kang, Yubin,Im, Byoungyong,Lee, Chan-Gi,Kim, Hangoo,Park, Kwang Hoon,Kim, Dae-Guen 한국재료학회 2020 한국재료학회지 Vol.30 No.1

In this study, the effects of Sm addition (0, 0.05, 0.2, 0.5 wt%) on the microstructure, hardness, and electrical and thermal conductivity of Al-11Si-1.5Cu aluminum alloy were investigated. As a result of Sm addition, increment in the amount of α-Al and refinement of primary Si from 70 to 10 ㎛ were observed due to eutectic temperature depression. On the other hand, Sm was less effective at refining eutectic Si because of insufficient addition. The phase analysis results indicated that Sm-rich intermetallic phases such as Al-Fe-Mg-Si and Al-Si-Cu formed and led to decrements in the amount of primary Si and eutectic Si. These microstructure changes affected not only the hardness but also the electrical and thermal conductivity. When 0.5 wt% Sm was added to the alloy, hardness increased from 84.4 to 91.3 Hv, and electric conductivity increased from 15.14 to 16.97 MS/m. Thermal conductivity greatly increased from 133 to 157 W/m·K.