• Tunnel and Underground Space
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• v.19 no.3
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• pp.248-260
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• 2009

With regard to oversea mineral resources development, recent trend has been changed from a simple capital investment to a direct development of the resources. In relation to the stability of a slope in large open-pit coal mine, groundwater system was investigated and the validity of horizontal drainage hole was evaluated in Pasir coal mine, Indonesia. In this work, various field tests were carried out for a characterization of groundwater system, which included in-situ permeability measurement, tracer test and monitoring of groundwater levels. Especially, the influence of SM river on the characteristics of the groundwater flow system was mainly inspected. For the permeability measurement, Guelph permeameter was employed, and was found that sandstone was more permeable than mudstone and coal seam. From a comparison of lithological structure and the results of groundwater level monitoring, sandstone and thin coal seam with fractures were found to be a main channel for groundwater flow. In the results of tracer tests, the effect of SM river on the groundwater system depends on the geological structure of its base. To identify the effect of horizontal drainage holes, 2-D groundwater modeling was performed. Four different cases were tested, which are different from the length of drainage hole and the existence of pond on top of the slope. To enhance the drainage effect and slope stability, the drainage hole should be drilled to the depth of coal seam layer, which provides a main pathway of groundwater flow and embedded by sandstone. For this purpose, correct identification of surrounding geology should be preceded.

• Journal of Environmental Science International
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• v.20 no.2
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• pp.241-249
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• 2011

In this research, equilibrium of adsorption and kinetics of As(V) removal were investigated. The coal mine drainage sludge(CMDS) was used as adsorbent. To find out the physical and chemical properties of CMDS, XRD (X-ray diffraction), XRF (X-ray fluorescence spectrometer) analysis were carried out. The CMDS was consist of 70% of goethite and 30% of calcite. From the results, an adsorption mechanism of As(V) with CMDS was dominated by iron oxides. Langmuir adsorption isotherm model was fitted well more than Freundlich isotherm adsorption model. Adsorption capacities of CMDS 1 was not different with CMDS 2 on aspect of amounts of arsenic adsorbed. The maximum adsorption amount of two CMDS were respectively 40.816, 39.682 mg/g. However, the kinetic of two CMDS was different. The kinetic was followed pseudo second order model than pseudo first order model. Concentrations of arsenic in all segments of the polymer in CMDS 2 does not have a constant value, but the rate was greater than the value of CMDS 1. Therefore, CMDS 2, which is containing polymer, is more effective for adsorbent to remove As(V).

• Journal of the Korean Society of Groundwater Environment
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• v.2 no.1
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• pp.38-47
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• 1995

This study was carried out in order to provide basic information on neutralization processes of acid mine drainage (AMD) from the abandoned Donghae coal mine in the Samchuk coalfield. The contents of potentially toxic elements in stream water increase and the level of pH decreases during dry season. Hydrated lime is turned out to be the best neutralizer of the acid mine water from a technical and economic viewpoint. From the results of equilibrium calculation, Fe and Al could be precipitated as FeOOH, and Al(OH)$_3$, respectively, in the neutralization process. The sites of holding basins necessary to equalize quantity and quality of AMD are recommended by GIS analysis, and the capacities of holding basins are determined by hydrological calculation.

• Journal of Soil and Groundwater Environment
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• v.14 no.1
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• pp.29-35
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• 2009

In this study, the effect of pH and temperature on the adsorption behavior of acid mine drainage (AMD) on coal mine drainage sludge (CMDS) has been investigated during the treatment of coal mine drainage (CMD) by electrical purification method. The pH$_{zero\;point\;charge}$ (pH$_{zpc}$) of CMDS was 5. The removal ratio of copper, zinc, cadmium, iron were increased according to the increase of pH value. The adsorption amount of copper showed 0.64 mg g$^{-1}$ sludge. It was independent of pH value. The adsorption amount of the other metals showed l.l times when pH was 3. The adsorption amount of chromium was a little bit increased at the pH value higher than 7 due to a small amount of the chromium was eluted as $Cr(OH)_6^{3-}$. The amount of metals' absorption were decreased according to temperature was increase at pH value was 3. The selectivity order was Cd>Fe > Zn > Cu. The amount of absorption showed q$_{max}$ Cu 2.747 mg g$^{-1}$ andZn 2.525 mg g$^{-1}$ when pH value higher than 5. It was independent of temperature.

• Economic and Environmental Geology
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• v.52 no.1
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• pp.29-35
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• 2019

The purpose of this study was to assess the applicability of acid mine drainage sludge (AMDS) pellets for the arsenic (As) stabilization and to suggest an evaluation method for arsenic stabilization efficiency in soil around abandoned coal mines. The soil samples were collected from the agricultural field around Ham-Tae, Dong-Won, Dong-Hae, and Ok-Dong coal mine. The As concentration in soil was exceeding the criteria of soil pollution level, except for Ham-Tae coal mine. The AMDS pellets are more appropriate to use by reducing dust occurrence during the transport and application process than AMDS powder. In addition, AMDS pellets were maintained the As stabilization efficiency. The application of AMDS pellets for the As stabilization in soil was assessed by column experiments. The AMDS pellets were more effective than limestone and steel slag, which used as the conventional additives for the stabilization process. The As extraction by $0.43M\;HNO_3$ or $1M\;NaH_2PO_4$ solution were appropriate evaluation methods for evaluation of As stabilization efficiency in the soil.

• Resources Recycling
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• v.19 no.2
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• pp.54-62
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• 2010

In order to obtain the basic data for recycling of coal mine tailings, the characteristics of coal mine tailings, the formation of AMD from the tailings and the leaching of heavy metal from the tailings were studied. The samples were characterized in terms of chemical composition, mineral composition and content of heavy metal of the tailings were investigated. The effects of time, temperature, content of pyrite, sulfide minerals on the formation of AMD were also investigated. For the leaching tests, the KS method, TCLP method and column test were used. From the investigated data, we can see that the coal mine tailings can be used as aggregate for filling used gallery. We can also see that the formation of AMD from coal mine tailings can be prevented by mixing 4% or more limestone with it.

• Journal of Soil and Groundwater Environment
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• v.26 no.6
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• pp.18-26
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• 2021

Soil aggregation begins with flocculation of clay particles triggered by interfacial reactions of polyvalent cation such as Ca²⁺ and Fe³⁺, and they are also known as important elements to control the mobility of arsenic in soil environment. The objective of this study was to investigate the feasibility of CMDS (coal mine drainage sludge) for soil loss reduction and stabilization of arsenic-contaminated soil in a 37% sloped farmland under rainfall simulation. The amount of soil loss decreased by 43% when CMDS was applied, and this result was not significantly different from the case of limestone application, which yielded 46% decrease of soil loss. However, the relative amount of dispersed clay particles in the sediment CMDS-applied soil was 10% lower than that of limestone-applied soil, suggesting CMDS is more effective than limestone in inducing soil aggregation. The concentrations of bioavailable arsenic in CMDS amended soil decreased by 46%~78%, which was lower than the amount in limestone amended soil. Therefore, CMDS can be used as an effective amendment material to reduce soil loss and stabilize arsenic in sloped farmland areas.

• Proceedings of the Petrological Society of Korea Conference
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• 2003.05a
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• pp.11-14
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• 2003

• Proceedings of the Mineralogical Society of Korea Conference
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• 2003.05a
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• pp.11-14
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• 2003

• Resources Recycling
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• v.29 no.6
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• pp.41-47
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• 2020

This study was carried out to utilize the coal bottom ash generated in a circulating fluidized bed combustion boiler as a treatment agent for heavy metal ions, and experiments were conducted to remove heavy metal ions from the acid mine drainage. The batch experiments were conducted to investigate the influence of dosage of ash, initial concentration of solution on the removal capacity of heavy metal ions (Cu, Cd, Cr, Pb). The results of the experiment showed that the total removal capacity of heavy metals was 30.8 mg/L and 46.4 mg/g, respectively, under the condition that the concentration of coal ash was added as 15 g/L of heavy materials and 10 g/L of light materials. After that, a long-term column experiment was performed to determine the maximum removal capacity of heavy metal ions (Cu, Cd, Cr, Pb, As), and the removal capacity for each metal component was investigated. After approximately 60 days of operation, the maximum removal capacity of heavy metals was 23.6 mg/g at pH 9.25.