• Journal of Soil and Groundwater Environment
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• v.13 no.3
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• pp.52-58
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• 2008

Mn-impregnated activated carbon (Mn-AC) prepared at different conditions was applied in the treatment of synthetic wastewater containing both organic and inorganic contaminants. Phenol and As(III) was used as the representative organic and inorganic contaminants, respectively. After evaluation of the physicochemical characteristic and stability of Mn-AC, oxidation of As(III) as well as adsorption of phenol by activated carbon(AC) and Mn-AC were investigated in a batch reactor. To investigate the stability of Mn-AC, dissolution of Mn from each Mn-AC was measured pH ranging from 2 to 4. Although Mn-AC was unstable at a strong acidic condition, the dissoluted Mn was below 3 ppm at pH 4. XRD analysis of Mn-AC indicated that the mineral type of the impregnated manganese was $Mn_2O_3$. From the simultaneous treatment of As(III) and phenol by AC and Mn-AC, As(III) oxidation by Mn-AC was greater than that by AC at lower pH, while the reverse order was observed at higher pH. After impregnation of Mn onto AC, 13% decrease of the surface area was observed, causing 8% reduction of phenol removal. Considering removal properties of As(III) and phenol, Mn-AC could be applied in the simultaneous treatment of wastewater contaminated with multi-contaminants.

• Resources Recycling
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• v.20 no.3
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• pp.28-39
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• 2011

This review investigated theoretical principals and practical application examples on recirculation system of soil washing-wastewater treatment-treated water recycling. As for technologies which have attempted to remediating metals-contaminated soil in and around country, there are reactive barriers, encapsulation, solidification/stabilization, soil washing, and phytoremediation. Among those, in particular, this review covers soil washing technology which physicochemically removes contaminants from soils. The major drawbacks of this technology are to generate a large amount of wastewater which contains contaminants complexed with ligands of washing solution and needs additional treatment process. To solve these problems, many chemical treatment methods have been developed as follows: precipitation/coprecipitation, membrane filtration, adsorption treatment, ion exchange, and electrokinetic treatment. In the last part of the review, recent research and field application cases on soil washing wastewater treatment and recycling were introduced. Based on these integrated technologies, it could be achieved to solve the problem of soil washing wastewater and to enhance cost effective process by reducing total water resources use in soil washing process.

• Journal of Soil and Groundwater Environment
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• v.12 no.1
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• pp.97-102
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• 2007

An environmental survey from three abandoned metal mine areas was undertaken on to assess the risk of adverse health effects on human exposure to heavy metals influenced by past mining activities. Tailings contained high concentrations of heavy metals may have a impact on soils and waters around the tailing piles. In order to perform the human risk assessment, chemical analysis data of soils, rice grains and waters for As, Cd, Cu and Pb have been used. The HQ values for heavy metals via the rice consumption were significantly higher compared with other exposure pathways in all metal mine areas. The resulting HI values in three mine areas were higher than 9.0, and their toxic risk due to rice ingestion was strong in these mine areas. The cancer risk of being exposed to As by the rice consumption from the A, B and C mine areas was $5.1\;{\times}\;10^{-3}$, $6.8\;{\times}\;10^{-3}$ and $3.1\;{\times}\;10^{-3}$, respectively. The As cancer risk via the exposure pathway of rice ingestion from these mine areas exceeds the acceptable risk of 1 in 10,000 set for regulatory purposes. Thus, the daily intakes of rice by the local residents from these mine areas can pose a potential health threat if exposed by long-term As exposure.

• Economic and Environmental Geology
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• v.54 no.6
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• pp.689-698
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• 2021

Since the mine reclamation scheme was implemented from 2007 in Korea, various remediation programs have been decontaminated the pollution associated with mining and 254 mines were managed to reclamation from 2011 to 2015. However, as the total amount of contaminated mine drainage has been increased due to the discovery of potential hazards and contaminated zone, more efficient and economical treatment technology is required. Therefore, in this study, the adsorption properties of arsenic was evaluated according to the adsorbents which were derived from water treatment sludge(Alum based adsorbent, ABA-500) and granular ferric hydroxide(GFH), already commercialized. The alum sludge and GFH adsorbents consisted of aluminum, silica materials and amorphous iron hydroxide, respectively. The point of zero charge of ABA-500 and GFH were 5.27 and 6.72, respectively. The result of the analysis of BET revealed that the specific surface area of GFH(257 m²·g^-1) was larger than ABA-500(126~136 m²·g^-1) and all the adsorbents were mesoporous materials inferred from N₂ adsorption-desorption isotherm. The adsorption capacity of adsorbents was compared with the batch experiments that were performed at different reaction times, pH, temperature and initial concentrations of arsenic. As a result of kinetic study, it was confirmed that arsenic was adsorbed rapidly in the order of GFH, ABA-500(granule) and ABA-500(3mm). The adsorption kinetics were fitted to the pseudo-second-order kinetic model for all three adsorbents. The amount of adsorbed arsenic was increased with low pH and high temperature regardless of adsorbents. When the adsorbents reacted at different initial concentrations of arsenic in an hour, ABA-500(granule) and GFH could remove the arsenic below the standard of drinking water if the concentration was below 0.2 mg·g^-1 and 1 mg·g^-1, respectively. The results suggested that the ABA-500(granule), a low-cost adsorbent, had the potential to field application at low contaminated mine drainage.

• Economic and Environmental Geology
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• v.37 no.1
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• pp.99-106
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• 2004

Pollution reduction and/or control technology becomes one of the pressing post-semiconductor research field to lead an advanced industrial structure. Soil/groundwater remediation techniques may act as a core technology which will create many demands on pollution reduction areas. A plenty numbers of abandoned metal mines were left without any remediation action in Korea, and it may be potential sources of heavy metal and As contamination in the ecosystem. In order to bring this soil contamination to a settlement, the emerging soil/groundwater remediation techniques should be introduced. Main research topics in the United States and Europe move towards the clean remediation technology without any secondary impact and the feasible application of developing technique into the field scale study. With these advantages, several soil/groundwater techniques such as electrokinetic soil processing, permeable reactive barrier, stabilization/solidification, biosorption, soil flushing with biosurfactant, bioleaching and phytoremediation will be summarized in this paper.

• Korean Journal of Plant Resources
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• v.27 no.4
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• pp.344-353
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• 2014

This study was carried out to analyze the effect of arsenic types on growth and arsenic accumulation ability of Pteris multifida. Among arsenic pollution sources, Sodium arsenate, Calcium arsenate, Sodium arsenite and Potassium arsenite were treated in horticultural compost contaminated with $500mg{\cdot}kg^{-1}$. P. multifida was cultivated for 12 weeks. The results of study, Calcium arsenate treatment showed slightly decreased growth of P. multifida. But, growth of P. multifida cultivated in the remaining arsenic treatment was similar to untreated control plot. With only short-term cultivation of 4 weeks, aerial part of P. multifida in Sodium arsenate treatment showed high arsenic accumulation of $2,289.5mg{\cdot}kg^{-1}DW$. The arsenic accumulation ($2,956.0mg{\cdot}kg^{-1}DW$) was the highest at 12 week. On the other hand, underground part showed the highest arsenic accumulation in Potassium arsenite treatment ($2,470.2mg{\cdot}kg^{-1}DW$) and Calcium arsenate treatment accumulated $1,060.7mg{\cdot}kg^{-1}DW$ of arsenic. Regardless of arsenic types, aerial part of P. multifida was absorbed more than $1000mg{\cdot}kg^{-1}DW$ of arsenic. And removal of arsenic in soil was also higher. Therefore, Pteris multida is considered to be suitable phytoremediation meterial of various arsenic contaminated areas.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.1
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• pp.51-59
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• 2010

The sediments and soils around a mine are likely to be exposed to contamination of arsenic (As) through mining operations. In this study, the factors associated with As movement in soils around a closed zinc (Zn) mine were evaluated by the relationship of As distributions to physico-chemical properties of soils. A sequential extraction scheme, based on a soil P fractionation, was used to assess the As distributionsin solid phases. A significant difference in As distributions was found between paddy and upland soils. While As contents of paddy soils increased with soil depth, those of upland soils decreased with soil depth. In upland soils, As showed additional significant relationships to oxides of Si, Al and Fe. Although a major fraction of As in soils was found to be in the NaOH extractable fraction, As exhibited highly significant relationship to the Zn species that apparently originated from the mine. Therefore, As mobility around Zn mine seems to be governed by mass flow of the particulates containing As-associated Zn in paddy soils, whereas retention reactions such as adsorption, complexation, and precipitation seem to predominate in upland soils.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.11
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• pp.1205-1214
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• 2005

This study was carried out to investigate the emission characteristics of volatile metals(Hg, As, Se) and semi volatile metals such as Pb from small and medium size municipal solid waste incinerators(MSWIs). The concentrations of Hg, Pb, As and Se in emission gas from small size waste incinerators were higher than those of medium size waste incinerators. This is probably due to less air pollutant control devices and high emission gas temperature of the small size waste incinerators relative to the medium size waste incinerators. Emission gas temperature from small and medium size waste incinerators were divided into 2 groups. The first group was about $100^{\circ}C$ and the second roup in the range of $400{\sim}700^{\circ}C$. The concentrations of emission gas at the second group were Hg $70.43\;{\mu}g/Sm^3$, Pb $0.94\;{\mu}g/Sm^3$, As $9.83\;{\mu}g/Sm^3$ and Se $5.05\;{\mu}g/Sm^3$. The concentrations of Hg, Pb, As and Se at the first group were lower than those found at the second group. Besides, the removal efficiencies of Hg in medium size waste incinerators were $55.2{\sim}95.9%$. Emission gas temperature reduction from waste heat boiler(WHB) contribute to control of Hg. Based on above results, we postulate that the temperature of flue gas should play a very important role in volatile metal control in small and medium size MSWIs. In order to improve the volatile metals removal efficiency, the temperature of cooling system must be controlled and the air pollution control device should be operated properly.

• Journal of the Korea Institute of Building Construction
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• v.12 no.1
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• pp.115-121
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• 2012

If cement could be manufactured with industrial byproducts such as granulated blast furnace slag, phosphogypsum, and waste lime rather than clinker, there would be many advantages, including the maximization of the use of these industrial byproducts for high value-added resources, the conservation of natural resources and energy by omitting the use of clinker, the minimization of environmental pollution problems caused by $CO_2$ discharge, and the reduction of the production cost. For this reason, in this study, mechanical behavior tests of non-sintered cement concrete were performed, and elasticity modulus and stress-strain relationship of non-sintered cement concrete were proposed. Nine test members were manufactured and tested according to reinforcement ratio and concrete compressive strength. According to the test results, there was no difference between general cement concrete and non-sintered cement concrete in terms of flexure and shear behavior.

• Journal of Soil and Groundwater Environment
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• v.14 no.6
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• pp.78-86
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• 2009

Applicability of CaO and steel slag as stabilizers in the treatment of field and paddy soils near Pungjeong mine contaminated with arsenic and cationic heavy metals was investigated from batch and column experiments. Immobilization of heavy metals was evaluated by TCLP dissolution test. Immobility of heavy metal ions was less than 15% when steel slag alone was used. This result suggests that $Fe_2O_3$ and $SiO_2$, known as the major component of steel slag, have little effect for the immobilization of heavy metal ions due to acidity of TCLP solution. Immobilization of cationic heavy metals was little affected by the ratio of CaO and steel slag while arsenic removal was increased as the ratio of steel slag to CaO increased. In the column test, concentrations of both arsenic and cationic heavy metals in effluents were below the water discharge guideline over the entire reaction period. This result can be explained by the immobilization of cationic heavy metals from the increased pH in soil solution as well as by the formation of insoluble $Ca_3(AsO_4)_2$. From this work, it is possible to suggest that arsenic and cationic heavy metals can be concurrently stabilized by application of both CaO and steel slag.