• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2005년도 INTERNATIONAL SYMPOSIUM ON SOIL & GROUNDWATER ENVIRONMENT
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• pp.59-61
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• 2005

In Korea, hundreds of abandoned and closed coal and metallic mines are present in the steep mountain valleys due to the depression of the mining industry since the late 1980s. From these mines, enormous amounts of coal waste were dumped on the slopes, which causes sedimentation and acid mine drainage (AMD) to be discharged directly into streams causing detrimental effects on soil and water environments. A limestone slurry by-product (lime cake) is produced from the Solvay process in manufacturing soda ash. It has very fine particles, low hydraulic conductivities ($10^{-8}{\sim}10^{-9}cm/sec$), high pH, high EC due to the presence of CaO, MgO and $CaCl_2$ as major components, and traces of heavy metals. Due to these properties, it has potential to be used as a neutralizer for acid-producing materials. A field plot experiment was used to test the application of lime cake for reclaiming coal wastes. Each plot was 20 x 5 m (L x W) in size on a 56% slope. Treatments included a control (waste only), calcite ($CaCO_3$), and lime cake. The lime requirement (LR) for the coal waste to pH 7.0 was determined and treatments consisted of adding 100%, 50%, and 25% of the LR. The lime cake and calcite were also applied in either a layer between the coal waste and topsoil or mixed into the topsoil and coal waste. Each plot was hydroseeded with grasses and planted with trees. In each plot, surface runoff and subsurface water were collected. The lime cake treatments increased the pH of coal waste from 3.5 to 6, and neutralized the pH of the runoff and leachate of the coal waste from 4.3 to 6.7.

• 한국토양비료학회지
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• 제47권6호
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• pp.533-539
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• 2014

Mine wastes such as acid mine drainage (AMD) can cause the detrimental effects on surrounding environment, thereby eventually threatening human health. Main objective of this study was to evaluate the neutralizing effect of fly ash (FA) as a stabilizing material AMD. Field plot was constructed in a coal waste depot which has caused aluminium-whitening adjacent to the stream. Different mixing ratios of FA were applied on a top of the soil, and then the physicochemical properties of runoff and soil were monitored. Constructed plots were as following: control (mine waste only (W)), mine waste + 20% ($w\;w^{-1}$)of FA (WC20M), mine waste + 40% ($w\;w^{-1}$)of FA (WC40M), and WC40M dressed with a fresh soil at the top (WC40MD). Result showed that initial pH of runoff in control was 5.09 while that in WC40M (7.81) was significantly increased. For a plot treated with WC40M, the concentration of Al in runoff was decreased to $0.22mg\;L^{-1}$ compared to the W as the control ($4.85mg\;L^{-1}$). Moreover, the concentration of Fe was also decreased to less than half at the WC40M compared to the control. Application of FA can be useful for neutralizing AMD and possibly minimizing adverse effect of AMD in mining area.

• 환경영향평가
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• 제16권1호
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• pp.35-43
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• 2007

Vitrified aggregates obtained by using mine tailings were evaluated using various leaching methods to assess their environmental safety. The leaching tests in this study include continuous batch leaching, Dutch availability leaching, pH-stat and tank diffusion test as well as TCLP (Toxicity Characteristic Leaching Procedure), which is commonly adopted. Vitrification technique has successfully been applied treating some solid wastes containing high level of heavy metals, such as EAF (Electric Arc Furnace) dust and mine tailings. The potentially most leachable element among trace metals was As and theoretically about 7% of total concentrations in the aggregate can be released under extreme condition. Zinc was leached about 4% and the other trace metals including Cd, Cr and Pb were hardly released from the vitrified mine tailing aggregate.

• 한국지구물리탐사학회:학술대회논문집
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• 한국지구물리탐사학회 2007년도 공동학술대회 논문집
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• pp.219-224
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• 2007

We conducted geophysical surveys to detect antitank mine at Namji-eup, Gyeongsangnam-do which had been installed during Korean war. The surveys consisted of 2 stages, at the first stage we divided the survey area into 7 block and carried out magnetic gradient survey and GEM-3 EM survey sequentially for each block. Hence we verified anomaly areas using an excavator and a metal detector. Most of anomalies were found to be garbages such as trash cans, metallic wastes, and so on. And also, the concrete pipe was found at depth of 1 m, which had not referred in any report of that area. At the second stage, after trenching the covered soil down to 75 cm the same surveys were conducted. We could not find the strong signal to be inferred from a antitank mine, but we pointed out some anomalies to need careful handling because demining is very dangerous work even though there is few possibility that is mine.

• 자원환경지질
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• 제33권2호
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• pp.139-146
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• 2000

Development of an effective liner by utilization of the tailings frm the Imcheon mine and polymer has been tried. The tailings piled in the Imcheon mine, whose true specific gravity is about 2.86, are composed mainly of quartz, alkali-feldspar, muscovite and pyrite, and mostly (93.7% in volume) coarser than sand grain size (50${\mu}{\textrm}{m}$). Strength, leaching and permeability tests have been performed on the test specimens of polymer concrete manufactured with various mixing proportions of tailings, unsaturated polyester resins(UPR), calcium carbonates, stone powder sludges and granite soils. Polymer concrete specimens with stone powder sludges or granite soils as fillers and aggregates indicate 2.5 to 3 fold higher flexural and compressive strengths and lower permeabilities than those with calcium carbonates, which shows their usability as a waterproof liner. Also, the polymer concrete liner with stone powder sludge fillers is more advisable in aspects of utilization of waste sludges than that with other fillers.

• 한국지하수토양환경학회지:지하수토양환경
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• 제10권3호
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• pp.1-8
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• 2005

석탄저장소, 텅스텐 광산의 광미, 고철 제련장내의 오염된 토양을 대상으로 중금속의 존재형태와 용출 가능성에 대하여 조사하였다. 석탄저장소와 광미, 제련장 지역 내 토양의 중금속 농도는 논과 비 오염지역의 산 토양보다는 높게 나타났으며, 대부분의 중금속의 존재형태는 reducible, organic과 residual fraction이 높게 나타났다. 오염되지 않은 토양의 중금속의 존재형태는 residual 형태가 주를 이루었다. 용출 가능성에 대한 평가는 오염되지 않은 토양보다는 오염된 토양에서 높게 나타났으며, pH 7.0 보다는 pH 4.0에서 시간이 증가함에 따라 용출량이 증가하였다. 오염 된 토양으로부터 중금속의 용출은 Cu, Zn, Pb 등이 용출시간이 25시간 또는 35시간에 유사 평형에 도달했다. 오염되지 않은 토양의 낮은 용출은 중금속의 존재형태 중 높은 residual fraction의 비율에 의해 기인된 것으로 사료된다.

• 한국환경복원기술학회지
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• 제14권6호
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• pp.71-85
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• 2011

In Okdong coal mine abandoned area, every year large amount of mine wastes have been swept away due to heavy rains in summer. Because pH of coal-mine waste is in the early 4, plant naturally does not grow there due to unfavorable condition for growing plant. This study had an experiment to grow plant for 6 months using Mycorrhizae which can be adapted well in acid soil. As a result of Experiment, In the infected experiment pot, 90% of the plants survived but in case of uninfected experiment pot, only 25% were alive. From Growth Experiment, it appeared that average stem length increase (cm/month), average fresh weight increase ($g^{fw}/month$), average dry weight increase ($g^{dw}/month$) were increased by 60%, 21%, 31% respectively. Especially, Mycorrhizae plays an important role in providing nutrients and water when seeding are established. Mycorrhizae prevents death caused by lack of nutrients and water and helps growth and development of plant when seeding are established in the early stage. This study proved that Mycorrhizae is comparatively effective in plant growth and prevention of erosion in coal-mine abandoned area.

• 자원리싸이클링
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• 제5권4호
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• pp.25-31
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• 1996

유용광물의 유실과 자연환경 훼손의 원인이 되는 석회석 광산 폐석을 자체 제작한 회전식 스크린 선별기를 이용하여 시멘트 제조용 원료로의 재활용방법의 개발을 시도하였다. 자체 제작한 회전식 선별기의 분리 조작에서는 시료의 수분함유량 6wt%이하, 시료의 선별기내 체류시간 15sec, 선별기의 회전수 600rpm의 조건에서 분리된 조대산물중의 CaO 품위는 37.36wt%에서 $42pm$2wt%로 상승하였다. 따라서, 광범위한 입도범위(수십Cm에서 1.0mm까지)를 가지는 시료를 효과적으로 분리 회수하기 위한 분리 공정을 수립하여 실험한 결과 분리된 조대산물중의 CaO 품위는 46.85wt%까지 상승하였다. 이 결과는 시멘트 제조용 원료로서 직접사용품위에는 불충분하지만 광산에서 폐석중의 dolomite의 선별이 가능하므로 직접 재활용이 가능할 것으로 추측된다. 한편 분리된 미립산물(점토류, 20mm이하)등은 전 공정에 걸쳐 안정적인 화학조성을 유지하고 있기 때문에 시멘트 제조용 부원료로서 직접 재활용이 가능할 것으로 판단된다.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2006년도 총회 및 춘계학술발표회
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• pp.41-44
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• 2006

The objective of this study was to evaluate the stabilization of As and heavy metals in tailings from the Samkwang Au-Ag mine with $Ca(OH)_2$. In order to evaluate the stabilization ability of As and heavy metals in the tailings, column test was implemented with various conditions as 1) particle size of $Ca(OH)_2$, 2) mixing method and 3) flow rate of eluents during 60 days. The results showed that addition with 5% of $Ca(OH)_2$ in 1kg of the tailings had the most effective ability of stabilization up to 95%. In addition, stabilization ability of As and heavy metals in tailings was enhanced using a fine powder of $Ca(OH)_2$. Therefore, stabilization technology can be used as a remediation of As and heavy metals in mine wastes including tailings and a nearby soils from abandoned metal mines.

• 한국토양환경학회지
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• 제3권1호
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• pp.31-44
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• 1998

본 연구는 중금속원소의 주오염원 중의 하나인 금속폐광산에 다량 잔존하는 폐석을 효율적으로 처리하기 위해 실내모형시험을 수행하였으며, 그 결과를 광산폐석처리의 기술개발에 기초자료로 활용하고자 한다. 실험의 도구는 실험결과에 거의 영향이 없는 내산성 내알카리성의 아크릴산수지와 폴리에틸렌 관을 사용하였다. 본 연구에서 제작 운용된 8개의 모형을 계내의 환경, 충진물의 배열방식 및 종류 등으로 분류한다면 4개의 그룹으로 나눌 수 있다. 그룹 1은 계내에 폐석으로만 충진하여 개방계에서 실험한 배경모델이고, 그룹 2는 각각 두 개의 폐석층과 석회암편층을 층상으로 배열한 뒤 개방계와 폐쇄계로 구분하여 실험하였다. 그룹 3은 폐석과 석회암편을 골고루 잘 섞어 계내에 충진하고(혼합모델)이를 개방계와 폐쇄계로 구분하여 실험하였으며, 마지막 그룹 4는 폐석층의 표층부에 석회암편층을 가하여 실험하였다. 배경모델인 모델 Ⅰ로부터 배수된 시수는 실험초기부터 말기까지 중금속원소의 용존량이 매우 높다. 그런, 다른 모델에 비해 그룹 3에 해당되는 모델 Ⅴ와 Ⅶ은 중금속원소의 함량이 매우 낮아 제거효과가 가장 높은 것으로 나타났다. 폐쇄된 혼합모델에서 폐석과 석회암편의 혼합비를 1:1, 2:1로 달리하더라도 중금속원소의 제거효과 는 대동소이한 것으로 나타났다. 그러나, 계내를 같은량의 충진물로 충진하더라도 혼합모델은 층상모델에 비해 중금속원소의 제거효과가 현저히 높다. 그리고, 다른 실험조건이 같은 폐쇄계와 개방계를 비교하면 전자의 중금속원소의 제거효과가 다소 높은 것으로 나타났다.