• Journal of Korean Society on Water Environment
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• v.23 no.2
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• pp.281-286
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• 2007

A chemical and biological permeable barrier with economic feasibility is suggested to treat landfill leachate in this study. The proposed composite layers consist of bentonite, and polyurethane (PU) foam that is mixed with powdered activated carbon (PAC) and inoculated with microorganisms from local wastewater treatment plant. Each layer is mixed with local sand, and yellow brown soil. Batch tests were conducted to investigate the sorptions of nitrate on the PU foam and PAC, and nitrification/denitrification rate of each layer material. Nitrification occurred in 30 minutes with initial ammonia concentration of 100 mg/L, and the concentration of nitrate attached in the PU foam increased after 270 minutes. Results of denitrification batch tests showed 76.6%, 87.3% and 88% of nitrate removal efficiency at 10%, 20% and 30% of the volume ratio of PU foam, respectively. The pH increased from 7 to 9.42, and alkalinity increased from 980 mg/L to 1720 mg/L during the denitrification batch tests. In the column experiments using the proposed composite layers with 20% of the volume ratio of the PU foam, about 96% of BOD, 63% of COD, 58.1~79.5% of total nitrogen were removed.

• Journal of the Korean GEO-environmental Society
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• v.10 no.6
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• pp.61-68
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• 2009

The main objective of this study was to examine the removal of heavy metals from water by inflated vermiculites. The component of vermiculites was analyzed by XRF, and the concentration of metal ion was measured by ICP-AES. Serial batch kinetic tests and batch sorption tests were conducted to determine the removal characteristics for heavy metals in aqueous solutions. As a result, solution pH values of tests with the inflated vermiculites generally increased and then stabilized. Equilibrium pHs were generally established within 5 hrs. In addition, removal rates of inflated vermiculites were tested at the initial concentration of 3 mg/L. As a result, at equilibrium concentration, except for chromium (36.23%), Most of the heavy metals were effectively removed (96.08~98.54%). Finally, sorption data were correlated with both Langmuir and Freundlich isotherms. The Qmax obtained from Langmuir isotherm were determined to Pb $725.4mg\;kg^{-1}$, Cd $568.8mg\;kg^{-1}$, Zn $540.2mg\;kg^{-1}$, Cu $457.2mg\;kg^{-1}$ Cr $0.9mg\;kg^{-1}$ respectively. The results of the study indicate that inflated vermiculites can be properly used as an adsorbent for various heavy metals because of its outstanding removal rate.

• Journal of Korean Society of Water and Wastewater
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• v.14 no.1
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• pp.99-107
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• 2000

In this article, the removal of surfactant by ozone and BAC was studied. Batch and pilot tests were carried out for these studies. In batch tests, efficiency of ozone oxidation process was evaluated for LAS(Linear Alkylbenzen Sulfonate) and SLS(Sodium Lauryl Sulfate) removal. Under oxidant conditions, the removal of LAS was more effective than that of SLS. The removal of surfactant was more enhanced with increasing pH in oxidant systems. Pilot tests are carried out with BAC single process and ozone oxidation/BAC combined process. The removal of LAS was more effective in ozone oxidation/BAC combined process than BAC single process about 10-20%. In the case of SLS, the efficiency of BAC single process was similar to that of ozone oxidation BAC combined process. According to temperature, the removal efficiency of SLS changed from 70% to 95% and initial concentration of surfactant had no effects on removal efficiency of SLC under applied temperature above $15^{\circ}C$.

• Membrane and Water Treatment
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• v.9 no.3
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• pp.173-179
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• 2018

Microcystin-LR, one of algal toxins induced by the eutrophication of a reservoir, is known to be harmful to human by adversely affecting our liver and brain. Hypochlorous acid is very efficient to remove Microcystin-LR in a clear well. The previous researches showed that CT, pH and temperature affected removal rate in batch tests. It was noted that hydrodynamic properties of clear well could also influence its removal rate. A mathematical model was built using an axial dispersion reactor model and software was used to simulate the removal rate. The model consisted of the second order differential equations including dispersion, convection, Microcystin-LR reaction with chlorine. Kinetic constants were obtained through batch tests with chlorine. They were $0.430{\times}10^{-3}L/mg/sec$ and $0.143{\times}10^{-3}L/mg/sec$ for pH 7.0 and 8.1, respectively. The axial dispersion reactor model was shown to be useful for the numerical model through conservative tracer tests. The numerical model successfully estimated the removal rate of Microcyctin-LR in a clear well. Numerical simulations showed that a small dispersion number, low pH and long hydraulic retention time were critical for higher removal rate with same chlorine dosage. This model could be used to optimize the operation of a clear well during an eutrophication season.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2006.04a
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• pp.37-40
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• 2006

The batch tests were performed to determine the ratio of hydrogen peroxide on diesel contaminated soil. The objective of test was to determine and optimize the hydrogen peroxide requirements for the remediation of a soil contaminated with diesel fuel. The batch test were done on 5g diesel contaminated soil containing hydrogen peroxide (34.5%). Initial diesel concentration were 2,000mg/kg, 5,000mg/kg, and 10,000mg/kg. The $Diesel(g):H_2O_2(g)$ ratio varied 1:1, 1:10, 1:50, 1:100, with contact reaction time 120 min. Results the batch test, effective ratio of $Diesel(g):H_2O_2(g)$ is 1:100.

• Journal of Korean Society of Environmental Engineers
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• v.37 no.4
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• pp.234-239
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• 2015

Various leaching tests were applied to the soil affected by accidental leakage of HF in an industrial area in Korea. Three different leaching methods including pH-stat, continuous batch leaching, and column tests were adopted to assess leaching characteristics and mobility of fluorine(F) in soil and the potential risks to ecosystem. Both natural and spiked samples were used for the leaching tests. F concentrations in the batch tests increased by leaching rapidly in the early stage of leaching and then maintained rather constant levels. Column leaching test also show similar result to that of the batch test. pH also controlled the leaching behavior of the soil. With increasing pH, more F was released in the pH-stat test. This is mainly due to the competition and exchange with hydroxyl ions, as pH increase to the alkaline range. Most of the F released by the accident seem to have removed in the very early stage of leaching, whereas some natural proportion from soil minerals are thought to have been released very slowly. Therefore, little F released during the accident remained, based on the results of this study on the samples after two years of the accident. We could conclude that soil contaminated by external effects such as chemical accidents should be managed immediately, especially with F.

• Journal of the Korean GEO-environmental Society
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• v.10 no.7
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• pp.25-32
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• 2009

The main objective of this study was to examine the removal properties of Cu from water by inflated vermiculites. The component of vermiculites was analyzed by XRF and the concentration of Copper ion was measured by UV-VIS. Serial batch Kinetic tests and batch sorption tests were conducted to determine the removal characteristics for Cu in aqueous solutions. The result shows that removal rate, $K_{obs}$, of Cu are 0.73, 1.52, and 1.71 for initial pH 3, pH 4, pH 5, respectively, and are 3.19, 1.90, and 0.73 for the initial concentration of $1mg\;L^{-1}$, $5mg\;L^{-1}$, $10mg\;L^{-1}$, respectively. It leads to the conclusion that the removal rates are inversely proportional to the initial Cu concentration and are increased proportionally to the initial pHs. Finally, Sorption data were correlated with both Langmuir and Freundlich isotherms. As a result, Langmuir and Freundlich models were well fitted to batch isotherm data with good values of the determination coefficient. but the determination coefficient value for the Freundlich model fit was slightly higher than that of Langmuir model (0.965 for the Freundlich model and 0.936 for the Langmuir model). Using the Langmuir model, the maximum sorption capacity ($Q_{max}$), Freundlich partition coefficient, and the numerical value of n wrer estimated as $1,250mg\;kg^{-1}$, $635.1L\;kg^{-1}$ and 1.69, respectively. These results show that the inflated vermiculites could be used as an excellent adsorbent for copper contained in various types of aqueous solutions.

• 한국지구물리탐사학회:학술대회논문집
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• 2003.11a
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• pp.581-589
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• 2003

The variable flotation response ores from different deposits results basically from mineralogical association and their differences. Development of new techniques for analyzing the metallurgical performance of flotation and other concentration processes is demanded even in the treatment of rather simple ores such as porphyry ores. Diagnostic metallurgical analysis can be used to quantify the most possible recovery processes. Several porphyry copper/gold ores around the world were used to examine the responses in flotation, gravity separation and cyanidation in order to define the linkage between the recovery processes for both copper and old values. Laboratory batch flotation, gravity separation and cyanidation tests were carried out on these samples. All results were used to correlate the relative recovery of copper and gold, and to predict the highest possible metal recovery in the system. The metallurgical predictions were made according to the flotation conditions used and gravity separation. The results of various concentration processes on each porphyry ore samples are presented and discussed. All seven samples have shown significantly different gold/copper metallurgy. The grade/recovery relationships of gold and copper in the laboratory batch tests for the best results and the plants are given in the Figures below. The results of laboratory tests show that the copper recoveries converged to about $90\%$, but the gold recoveries were spread over $55-80\%$, except the K S ore. Series of standard cyanidation tests on the flotation concentrate samples and gravity separation using Knelson Separator on heads ores were carried out to cross-link the metallurgy and mineralogy of gold in the porphyry ores.

• Journal of Soil and Groundwater Environment
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• v.25 no.1
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• pp.53-61
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• 2020

This study assessed the feasibility of coal mine drainage sludge (CMDS) as a stabilizing agent for mercury contaminated soil through pot experiments and batch tests. In the pot experiments with 43 days of lettuce growth, the bioavailability of mercury in the amended soil and mercury content of the lettuce were decreased by 46% and 50%, respectively. These results were similar to those of the soil amended with the sulfide compound (FeS) generally used for mercury stabilization. Thus, CMDS could be an attractive mercury stabilizer in terms of industrial by-product recycling. Batch tests were conducted to examine mercury fractionation including reactions between the soil and acetic acid. The result showed that some elemental fraction changed to strongly bounded fraction rather than residual (HgS) fraction. This made it possible to conclude that mercury adsorption on oxides in CMDS was the major mechanism of stabilization.

• Journal of the Korean Society of Groundwater Environment
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• v.4 no.2
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• pp.78-84
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• 1997

Batch and column tests were performed to investigate the sorption capacity of bottom soils of Kimpo metropolitan waste landfill. Sorption capacity and sorption isotherm from the batch test for inorganic and heavy metal substances and retardation capacity of heavy metals from the column test are obtained. It was recognized from the tests that the samples match well with Freundlich isotherm and marine clay has good sorption capacity for potassium and heavy metals such as lead and cadmium. The soil samples with different geologic origins did not show significant differences in the sorption capacity of tested components.