• 한국안전학회지
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• 제15권4호
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• pp.127-133
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• 2000

The incomplete treatment of the swinery wastewater is one of the major factors of the river contamination resulting from an eutrophication. Even through many treatments were considered to reduce the contamination of the river by the swinery wastewater, the most effective treatment was not developed yet. Therefore, this project was focused on the development of the treatment that was a low cost and a high efficiency using a steel-making slag. The swinery wastewater was passed through a U-type tube packing the slag in the laboratory. And the swinery wastewater was cleaned effectively in the laboratory experiment. Based on these laboratory results, the treatment facility in a stock farm was constructed to confirm the effect of slag on the first-treated swinery wastewater. After the treatment of the first-treated swinery wastewater through the slag, the water quality of the river was improved and the biodiversity was increased.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2018년도 춘계 학술논문 발표대회
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• pp.91-92
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• 2018

A glassy thin film was formed on the surface of the blast furnace slag. When blast furnace slag is used as an admixture of concrete, addition of alkali activators were required. However, alkali activators are not only dangerous as chemical products, but they are also difficult to use as expensive materials. Therefore, it is necessary to study the way of removal of the glassy thin film of blast furnace slag without the risk and cost increase. In this study, to solve this problem, experiment was carried out to improve the hydration reactivity by treatment the surface of blast furnace slag using arc discharge. Experimental results show that when the surface of the blast furnace slag was tratmented by arc discharge, the glassy thin film was destroyed. And the hydration reactivity was improved, the compressive strength was increased.

• 자원리싸이클링
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• 제18권3호
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• pp.36-41
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• 2009

본 연구에서는 철강 산업 부산물인 전기 아크로에서 발생되는 슬래그(이하 EAF-slag 표기)를 탄산화 반응에 따른 슬래그이 물성변화 및 몰탈 시험을 통해 콘크리트용 대체 골재로써의 가능성을 검토하였으며, 특히 본 연구에서는 탄산화 처리에 따른 EAF-slag의 물성 변화에 대하여 논하였다. 연구 결과 EAF-slag의 탄산화 처리에 따라 EAF-slag 입자 표면에 칼사이트가 생성되면서 골재로써의 표면 기공율을 감소하였으며, pH도 7까지 안정화되는 것을 확인할 수 있었다. EAF-slag를 모래 대체에 따른 몰탈 압축 강도실험 결과 EAF-slag의 모래 대체 50%의 경우 7일 강도뿐만 아니라 28일 강도 증가도 함께 관찰되었다.

• Membrane and Water Treatment
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• 제9권3호
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• pp.181-188
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• 2018

A sidestream contains the filtrate or concentrate from the belt filter press, filter backwash and supernatant from sludge digesters. The sidestream flow, which heads back into the sewage treatment train, is about 1-3% less than the influent flow. However, the sidestream can increase the nutrient load since it contains high concentrations of phosphorus and nitrogen. In this study, the removal of PO4-P with organic matter characteristics and bacteriological changes during the sidestream treatment via ladle furnace (LF) slag was investigated. The sidestream used in this study consisted of 11-14% PO4-P and 3.2-3.6% soluble chemical oxygen demand in influent loading rates. LF slag, which had a relatively high $Ca^{2+}$ release compared to other slags, was used to remove $PO_4-P$ from the sidestream. The phosphate removal rates increased as the slag particle size decreased 19.1% (2.0-4.0 mm, 25.2% (1.0-2.0 mm) and 79.9% (0.5-1.0 mm). The removal rates of dissolved organic carbon, soluble chemical oxygen demand, color and aromatic organic matter ($UV_{254}$) were 17.6, 41.7, 90.2 and 77.3%, respectively. Fluorescence excitation-emission matrices and liquid chromatography-organic carbon detection demonstrated that the sidestream treatment via LF slag was effective in the removal of biopolymers. However, the removal of dissolved organic matter was not significant during the treatment. The intact bacterial biomass decreased from $1.64{\times}10^8cells/mL$ to $1.05{\times}10^8cells/mL$. The use of LF slag was effective for the removal of phosphate and the removal efficiency of phosphate was greater than 80% for up to 100 bed volumes.

• Advances in environmental research
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• 제8권1호
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• pp.55-69
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• 2019

The generation of ferrous slag, an industrial by-product from the iron ore industry, results in serious environmental problems. The chemical compositions indicate 30-34% SiO₂, 30-34% CaO, 18-22% Al₂O₃ and 0.5-0.6% Fe₂O₃. The specific gravity, moisture content and pH are in the range of 1.3-1.65, 9.1-10% and 8.5-9.0 respectively. The major part of the slag is composed of sand-size particles. The problems of disposal of slag could be minimized by considering its use in various environmental engineering applications providing additional value to the by-product. This paper mainly focuses on the potential utilization and valorisation of ferrous slag in both water and wastewater treatments. It is effective for the treatment of water and wastewater containing nutrients, heavy metals and polluted river/stormwater.

• 상하수도학회지
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• 제22권4호
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• pp.413-420
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• 2008

In order to utilize cinder melting slag as a filter media to control the quality of early rainwater, its environmental stability was verified by heavy metal elution experiment and improved by pre-treatment. Possibilities of improving its function as an absorbent was considered. Absorption characteristics of melting slag before and after the pre-treatment were analyzed by heavy metal equilibrium and stationary-phase column experiments, which in turn were analyzed by comparison experiment with activated carbon. As a result of heavy metal elution experiment, every metal item existed in a much lower amount than the criteria or was not detected, implying that there is no problem recycling it. Absorption equilibrium experiment showed that the time for pre-treatment melting slag to reach the equilibrium was reduced, while the absorbed amount was greatly increased. Stationary-phase column experiment assures us that the elimination rate was not changed much by influx rate, pH and the change in packing volume rate, indicating that this melting slag can be used not only as a filter media to control the quality of early rainwater but also in many areas of water-processing.

• 청정기술
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• 제6권2호
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• pp.85-92
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• 2000

제강슬래그의 재활용 범위를 확대하기 위한 방안으로 제강슬래그를 여재로 이용하여 축산폐수 처리효과를 조사하였다. 제강슬래그를 접촉용 여재로 활용한 순환식 폐수처리 장치를 이용하여 기존의 시설에서 처리된 축산폐수를 재처리한 결과 pH는 제강슬래그의 특성으로 인하여 상승하였으며 질소와 인의 농도를 효과적으로 낮추었으며 COD와 BOD도 감소하였다. 축산단지의 현장실험 결과 여재로 사용한 제강슬래그는 부유물질을 효과적으로 제거하였으며 유입 농도의 갑작스런 변화를 완화하였다. COD와 BOD의 경우 재처리수에서 항상 유입 폐수보다 낮아졌으나 유입수의 농도에 영향을 받았다. 에이징된 제강슬래그를 열처리 한 경우 free-CaO 성분의 증가로 열처리를 하지 않은 경우에 비하여 처리수의 pH 상승 정도가 커졌으며 인 제거 특성도 향상되었다.

• 한국세라믹학회지
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• 제18권1호
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• pp.3-12
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• 1981

A glass-ceramics based on blast-furnace slag, with some additives to the theoretical composition in order to control properties of mother glass and the heat treatment conditions, has been investigated. The raw materials in this study were blast-furnace slag, serpentine, feldspar and quartz as mother glass ingredients. Titanium dioxide and chromite were used as the nucleating agents. Batch compositions of the prepared glasses and ceraming conditions were found by trial and error method. The optimum conditions were confirmed by analyzing several measured physical properties such as density change during heat treatment, microhardness of slag-ceramics prepared, viscosity change of glass at heat treatment temperatures, nucleation density change, dilatometric properties, differential thermal analysis, identification of the grown crystal and crystal sizes. The batch composition feasible to prepare slag-ceramics was 40% of blast-furnace slag, 25% of serpentine, 18% of feldspar and 17% of silica sand. Three percent titanium dioxide and 1% chromite of the mother glass were added as nucleating agents. The ceraming conditions under which the slag-ceramics having considerably good properties can be developed found as: "The glass was heated at 75$0^{\circ}C$ for 2 hours for nucleation, and the temperature was raised up to 1, 00$0^{\circ}C$ with a rate of 0.75$^{\circ}C$/min for crystal growth.owth.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2003년도 가을 학술발표회 논문집
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• pp.318-321
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• 2003

Steel slag is produced during steel making process. Compared with the blast furnace slag, converter slag has the expansibility due to the reaction with water and free CaO. Therefore it is specified in Standard Specification for Concrete in Korea that steel slag aggregate must not be used in concrete. In this study, atomized steel slag aggregate is conducted from converter slag by the atomizing method. Atomized steel slag and conventional converter slag are same in its composite by nature in the converter but compounds of the composite become different because of different method of slag treatment. Especially atomized steel slag aggregate overcomes expansibility that is the weak point for usage. It is researched whether it has the possibility, suitability for fine aggregate in concrete. Slump and air content are measured in fresh concrete, compressive and bending strength in hardened concrete. These is compared with control concrete with washed sand.

• 한국토양비료학회지
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• 제32권3호
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• pp.295-303
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• 1999

제강슬래그의 작물재배시 산성토양개량제로서의 이용 가능성을 밝히기 위해 1997년에 공시품종을 동진벼로 하여 순천시 인안동의 간척논, 보성군 유정기 깨시무늬병 대량 발생논 그리고 나주시 남평의 실험논에 무처리, 제강슬래그 4, 8, $12Mg\;ha^{-1}$ 그리고 석회 $2Mg\;ha^{-1}$를 처리하여 벼를 재배하였다. 토양 pH, Ca, Mg, Fe 그리고 규산함량은 제강슬래그 시용량이 증가할수록 높아지는 경향이었다. 토양 pH의 증가는 주로 Ca함량의 증가에서 기인한 것으로 나타났으며 Fe함량은 처리 후 시간이 경과함에 따라 급격히 감소하다가 점차 안정된 값을 보였다. 토양 규산함량도 제강슬래그 시용량이 증가할수록 점차로 높아지는 경향이었고 무처리구나 석회 $2Mg\;ha^{-1}$ 처리구에 비해 유의하게 높아 제강슬래그가 산성토양 개량제, Fe 또는 Si의 공급원으로 이용가능성이 있음을 알 수 있었다. 석회 $2Mg\;ha^{-1}$수준의 토양 Ca함량은 제강슬래그 4 또는 $8Mg\;ha^{-1}$ 처리의 그것과 비슷하여 석회 시용에 의한 토양개량 효과를 얻기 위해서는 석회 시용량의 2~4 배의 제강슬래그를 시용해야 함을 알 수 있었나. 식물체내 무기화학성분 중 식물체내 무기화학성분 중 식물체내 Ca, $SiO_2$ 그리고 Fe함량은 제강슬래그 시용량이 증가할수록 높아지는 경향이었다. 제강슬래그 시용구에서는 생육후기로 갈수록 제강슬래그 4와 $8Mg\;ha^{-1}$ 처리구에서 생육이 양호하였으며 생육후기까지 지속적인 생장이 이루어져 생육후기에는 석회 처리구나 무처리구의 생육량을 능가하였다. 정조수량 및 수량관련 형질은 제강슬래그 4나 $8Mg\;ha^{-1}$ 처리에서 가장 높아 최고 수량을 얻기 위한 제강슬래그 처리수준은 $4{\sim}8Mg\;ha^{-1}$정도로 판단된다.