• 한국지하수토양환경학회지:지하수토양환경
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• 제19권5호
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• pp.1-8
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• 2014

The metals contamination of farmland soil nearby abandoned metal mine was serious problem in Korea. Stabilization of contaminated soil was reported using various stabilizers. Application of limestone and steel refining slag was reported as effective stabilizers in the stabilization of metals. The batch studies confirmed that the mixture of limestone and steel refining slag was suitable for stabilization of metals in contaminated soil. The limestone and steel refining slag mixture (2 : 1 and 3 : 2) were used in column studies and it was confirmed that the stabilizers effectively stabilized heavy metals in contaminated soil. The pH of the soil was increased with the addition of stabilizers. Total leached concentration of metals from the column study was reduced 44, 17, and 93% in comparison to the control at arsenic, cadmium and copper, respectively. The sequential extraction studies showed that the exchangeable fraction was changed into carbonate bound fraction (Cd and Cu) and Fe-Mn oxide bound fraction (As). Based on the results we confirmed that 2:1 ratio of limestone and steel refining slag effectively stabilizes the heavy metals. The mixed treatment of lime stone with steel refining slag would be an effective and feasible method for controlling metals leaching in contaminated soil.

• 한국재료학회지
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• 제13권4호
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• pp.239-245
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• 2003

In order to explore the possibility to extract precious metals from PCB(Printed Circuit Board) scrap by gravity separation, a high temperature melting process was adopted, from the recycling view point, to investigate the influence of viscosity on A1$_2$$O_3$-CaO$-SiO_2$ slag system composed of PCB scrap. For optimizing the pre-treatment process of PCB scrap, an experimental condition for the complete calcination and oxidation of organic materials in PCB scrap was established and a quantitative analysis of oxidized PCB scrap was also carrie out. It was found that 6 hours were enough for the complete oxidation of PCB scrap at 1273 K in an atmosphere condition. A slag, l5wt%$A1_2$$O_3$-45wt%CaO-40wt%SiO$_2$, was chosen as a basic slag composition which is determined based on the quantitative analysis of PCB scrap. Viscosities were measured in slag systems both made from pure fluxes and from PCB scrap with additional fluxes. Slag viscosities composed of pure fluxes were measured to be 5.29 poise and 30.52 poise at temperatures of 1773 and 1573 K, whereas that of PCB scrap with additional fluxes were 3.37 poise and 69.89 poise, respectively.

• 농업과학연구
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• 제51권2호
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• pp.227-238
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• 2024

Methane (CH₄) is an important greenhouse gas, with a short-term greenhouse effect 80-fold that of carbon dioxide. Blast furnace slag used as a base ingredient for silicate fertilizer, and contained Fe³⁺, which acts as reduction of CH₄ emissions in flooded rice paddy. This study was evaluated the effects of the silicate fertilizer with different rates of the iron slag on CH₄ emissions and rice growth. In this study, the SF 0.0% was applied with silicate fertilizer containing 0.0% of the iron slag, while the SF 2.5% and SF 5.0% were treated with silicate fertilizer containing 2.5 and 5.0%, respectively. The CH₄ emissions during rice cropping period were assessed using a closed-chamber method and then determined by Gas chromatography. The CH₄ fluxes were reduced by 17% (SF 0.0%), 17% (SF 2.5%), and 8% (SF 5.0%) compared to the treatment with only-inorganic fertilization (control). Conversely, rice grain yield increased by 15 - 30% compared to the control owing to the improvement of soil quality by silicate fertilization. In particular, soil pH, available phosphorus and available silicic acid content were increased with the increase in the iron slag rates from 0.0 to 5.0%. These contributed to a significant increase in rice growth such as 1,000-grains weight and percentage of filled grains. Consequently, these findings were indicated that the application of silicate fertilizer containing 2.5 - 5.0% of iron slag would be the most effective in both CH₄ reduction and rice growth.

• 자원리싸이클링
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• 제32권2호
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• pp.3-11
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• 2023

본 연구에서는 Waelz Kiln(WK) 공정에 의해 발생되는 슬래그로부터 물리적 처리에 의해 60% 이상의 품위를 가지는 철 농축산물을 얻고자 하였다. 대상 WK 슬래그는 수 mm 크기의 조립자로서 슬래그의 T-Fe 함량은 40.24%, ZnO 함량은 1.03%으로 확인되었다. WK 슬래그는 실험실 로드밀을 이용하여 다양한 분쇄시간 동안 분쇄하였으며, 분쇄된 시료는 우선 저자력(0.05 T) 세기에서 선별되었다. 그 결과, 10분 분쇄된 시료에서 가장 높은 철 품위를 나타내었으며, 20분 분쇄시료를 대상으로 자력세기에 따라 실험한 결과, 보다 고자력인 0.8 T에서 가장 높은 품위 및 최고 수준의 회수율이 관측되었다. 앞선 결과들을 바탕으로 본 연구에서는 최적의 관련 물리적 처리공정을 제안하였으며, 최적 공정에 의해 얻어진 철 농축산물의 품위 그리고 농축율은 각각 61.34% 그리고 1.52으로 평가되었다.

• 한국토양비료학회지
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• 제44권6호
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• pp.1016-1022
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• 2011

본 연구는 논 토양에서 규산질 비료의 성상이 다른 두 종의 규산질 비료의 토양 시비를 통한 토양의 화학적 특성 변화와 벼의 화학적 영양 성분을 평가하고자 수행하였다. 강원도 춘천시 소재 논 토양에서 두 종 (슬래그를 이용한 입상 규산질 비료와 수용성 입상 규산질 비료)의 규산 처리 수준에 따른 토양환경 변화를 보기 위해 무처리와 관행시비, 처리 기준의 0, 1, 2, 4배 처리 후 토양 화학적 변화를 고찰하였다. 슬래그를 이용한 규산질 비료의 처리 시 토양 pH는 시험 전 토양 pH에 비하여 상승하였으나 수용성 규산염을 원료로 한 규산질 비료의 처리 시에는 pH의 변화가 나타나지 않았는데 이는 수용성 규산염의 처리 양이 적고 가수분해율이 적기 때문인 것으로 판단된다. 슬래그를 이용한 규산질 비료를 처리한 구의 토양 유효규산 함량은 15일과 35일까지는 슬래그를 이용한 모든 규산질 비료 처리 구에서 증가하였다. 하지만 처리 60일 후부터는 유효규산 함량이 감소하는 것으로 나타났으나 수용성 규산염을 원료로 한 규산질 비료의 경우에는 토양 유효규산 함량의 증가가 대조구와 비교하여 볼 때 매우 적게 증가한 것으로 나타났다. 슬래그를 이용한 규산질 비료 처리구에서는 처리량에 관계없이 무처리 구에 비해 치환성 칼슘과 유효 인산 함량이 증가하는 것으로 나타났으나 최고 수준 (4배)의 처리구에서의 유효 인산 함량은 비례적으로 증가하지는 않았다. 슬래그를 이용한 규산질 비료 처리구에서의 볏짚의 규산 함량은 무처리구와 관행 처리구에 비해 모두 증가하는 것으로 나타났다. 즉, 규산질 비료를 처리함에 따라 규질비 ($SiO_2$/N)가 증가하였다. 관행 처리구와 슬래그를 이용한 규산질 비료 100% 처리시의 규질비는 각각 8.4와 11.5로 나타났다. 본 실험의 연구 결과를 통하여 슬래그를 이용한 규산질 비료의 토양시비는 토양의 화학적 성질 개선 및 수도 생육을 위해 바람직하나 수용성 규산질 비료의 경우에는 엽면 시비를 통한 액상 분무 등을 통하여 시비를 하는 것이 바람직하다고 판단된다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2008년도 춘계 학술발표회 초청강연 및 논문집
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• pp.920-925
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• 2008

In this presentation, a leaching experiment which is followed the pH changes(pH=4, pH=7) and the mixing rates(1%, 3%, 5%, 7%) was carried out to examine the arsenic reduction effects and the leaching characteristics on arsenic contaminated soil after stabilization treatment in which 5 materials were used as stabilization agencies, i.e. ZVI(zero valent iron), blast furnace slag, steel refining slag, quick lime, and oyster shell meal. Except for blast furnace slag, the arsenic removal rate increased as the mixing rate increases of stabilization agencies. Arsenic leaching concentration was indicated that pH=7 condition is higher than pH=4 condition. This result shows because arsenic immobilization reaction increases as pH decreases, and arsenic adsorption takes place as pH decreases.

• 산업기술연구
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• 제29권A호
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• pp.55-60
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• 2009

Stabilization treatment is one of processes for wastes and their components to reduce their toxicity and migration rates to surroundings. Inorganic binders such as calcium hydroxide, blast furnace slag and red mud were tested for their potential applicability to in-situ stabilization of heavy metal contaminated tailings in the abandoned metal mines. Columns(150mm dia. ${\times}$ 450mm length) filled with mixtures of inorganic binders and tailing from the Geumjang mine with various mixing ratios of binders to tailings, 5%, 7% and 9% were applied artificial rainfall tests for 28 days. Effluents from columns filled with calcium hydroxide and tailing showed high pH's of ~12.5 and a increasing trend of concentration in Pb and Zn with a significant decrease in permeability in terms of elapsed days. Those with burning slag and tailing showed pH's of ~8.5 and significantly low concentrations in heavy metals with a stable permeability. In case of red mud, effluents showed significantly low concentrations in heavy metals but a decreased permeability with pH's of ~10.5. Conclusively, this basic study suggests burning furnace slag be a potential stabilizer for effective treatment of heavy metal contaminated mine tailings.

• 한국물환경학회지
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• 제20권3호
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• pp.215-222
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• 2004

The sewages produced from small villages, rural community, drinking water reservation area and park which doesn't have sewage piping system can be caused a serious water pollution at the restricted areas. The objective of this research was to suggest an economical and effective sewage treatment method by investigating the removal of the organics, nitrogen, and phosphorus in the multi-soil-layering reactor. Soil, natural zeolite, and iron slag were used as a supporting media of multi-soil-layering in this research. The purpose of natural zeolite addition was to maintain the consistent ammonium exchange capacity by providing a sequential environment, and that of iron slag addition was to remove phosphorus by adsorption. Continuous experiment of lab-scale single-soil-layering (S-1), multi-soil-layering (S-2), and mixed-soil-layering (S-3) methods were studied to compare and optimize three different types of the reactors. The organic removal efficiencies showed more than 90% in all three reactors. While S-1 and S-3 reactors showed about T-N removal of 31%, 45%, respectively, the average T-N removal efficiency of the S-2 reactor represented an 87%. In conclusion, that results suggest that the multi-soil-layering reactor could be effectively utilized as a plant for treatment of small village sewage.

• 한국토양비료학회지
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• 제50권6호
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• pp.663-673
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• 2017

Heavy metal(loid) contamination of rice is the main issue in abandoned metal mine area with regard to food safety. A field study was conducted in mine area to see if soil amendments treatment including calcium superphosphate, sulfur, steel slag and S-containing fertilizer could reduce As and/or Cd content in rice grain and increase the growth of rice. The As content in brown rice reduced to 60% compared to the control only in $7.0Mg\;ha^{-1}$ of steel slag treatment. Cd reduction in rice was thought to be not the effect of amendments but the result from the difference in growth and development of rice plant and this could be ascribed to low soil Cd availability to rice plant. Compared with control, increased rice yield of cultivar Hwanggeumnuri was 1.3~2.2 and $1.5Mg\;ha^{-1}$ in calcium super phosphate and S-containing fertilizer treatment, respectively and the trend was also observed in cultivar Ungwang. However, steel slag treatment reduced the Ungwang yield by $0.4{\sim}0.9Mg\;ha^{-1}$. Future work will be needed to establish the agricultural measure with which secure the safety and yield of rice simultaneously.

• 한국세라믹학회지
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• 제17권1호
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• pp.27-34
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• 1980

The synthesis of glass-ceramic materials from glasses based on industrial wastes or natural rocks their physical properties were studied. Glasses of composition, CaO14.7∼16.1, MgO7.4∼9.0, Al2O38.3∼19.3, SiO2 48.9∼51.0wt% were prepared from domestic blast furnace slag, serpentine, sea sand and etc. with additions of chromic oxide, and fluoride as nucleating agent. The glasses were subjected to controlled heat treatments and yielded fine microstructure of glass-ceramics which were composed of monocrystalline phase of aluminous diopside. X-ray diffraction techniques were adopted to identify the crystalline phases and to determine the degree of crystallization quantitatively. Density, coefficient of thermal expansion, young's modulus, microhardness and modulus of rupture were measured and the resulting properties were discussed in terms of the heat-treatment conditions, the degree of crystallization, species of crystaline phase, the microstructures formed in glass-cramics and the chemical compositions of mother glasses.