• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.04a
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• pp.107-110
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• 2003

Reduction of nitrate by zero valent iron (Fe$^{0}$ ) has been previously studied, but the proper treatment for the by-product of ammonium has not been reported. However, in terms of nitrogen contamination, ammonium may be regarded as another form of nitrogen contaminants since it can be oxidized to nitrate again under aerobic conditions. This study is focused on simultaneous removal of nitrate and its by-product of ammonium, with the ZanF (Zeolite anchored Fe), a product derived from zeolite modified by Fe(II) chloride followed by reduction with sodium borohydride. Batch experiments were performed without buffer at two different pH condition with ZanF, iron filing, Fe(II)-sorbed zeolite, and pure zeolite to estimate the nitrate reduction and the ammonium production. At higher pH, removal rate of nitrate was reduced in both ZanF and iron filings. ZnF removed 60 % of nitrate at initial pH of 3.3 with no production of ammonium, while iron filing showed equivalent production of ammonium to the reduced amount of nitrate. In terms of nitrogen contamination, ZanF removed about 60 % and 40 % at initial pH of 3.3 and 6, respectively, while iron filing presented negligible removal against total nitrogen including nitrate and ammonium.

• Journal of Soil and Groundwater Environment
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• v.16 no.6
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• pp.1-9
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• 2011

A bibliographical review of Gy sampling theory for particulate materials was conducted to provide readers with useful means to reduce errors in soil contamination investigation. According to the Gy theory, the errors caused by the heterogeneous nature of soil include; the fundamental error (FE) caused by physical and chemical constitutional heterogeneity, the grouping and segregation error (GE) aroused from gravitational force, long-range heterogeneous fluctuation error ($CE_2$), the periodic heterogeneity fluctuation error ($CE_3$), and the materialization error (ME) generated during physical process of sample treatment. However, the accurate estimation of $CE_2$ and $CE_3$ cannot be estimated easily and only increasing sampling locations can reduce the magnitude of the errors. In addition, incremental sampling is the only method to reduce GE while grab sampling should be avoided as it introduces uncertainty and errors to the sampling process. Correct preparation and operation of sampling tools are important factors in reducing the incremental delimitation error (DE) and extraction error (EE) which are resulted from physical processes in the sampling. Therefore, Gy sampling theory can be used efficiently in planning a strategy for soil investigations of non-volatile and non-reactive samples.

• Journal of Soil and Groundwater Environment
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• v.20 no.3
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• pp.1-6
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• 2015

The rapid industrial development is facing problem due to energy depletion in Korea. So that, it can be necessary to develop alternative energy sources. Alternative energy like biofuels can be produced by using waste fuel, which is ecofriendly. As we know, the organic waste was banned to dump in landfill and ocean dumping. The most practicable method usually used to reduce organic waste is getting feedstuff or composting, considering the discharge characteristics of agricultural by-products waste treatment were selected. In this study, bio-coal was made using agriculture by product. Biocoal was prepared by adding 50 g of uniformly mixture into reactor and was carbonized at low temperatures 210, 220, and 230℃. The time of reaction was 1, 2 and 3 hours. Bio-coal approximately was similar to the standard of solid fuels. Other characteristics of fuel were also studied. The experiments which were analyzed were moisture content and calorific value, ash, chlorine, sulfur and heavy metals analysis as mercury, cadmium, lead, arsenic, and chromium. As a result, bio-coal 220℃, 2 hours was the optimal conditions while heating.

• Journal of Korean Society on Water Environment
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• v.31 no.2
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• pp.209-215
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• 2015

The purpose of this study is to evaluate the characteristic of the iron oxide carrier for removing arsenic contained in the groundwater. 4 types of iron oxide carrier used in the study is iron oxide coated sand carrier (IOCSC), iron oxide coated zeolite carrier (IOCZC), iron oxide plasticity carrier (IOPC) and platinum iron oxide plasticity carrier (PIOPC). The results of this study, IOPC is showed high arsenic adsorption strength and the maximum amount of adsorption than the IOCC. Based on the results of the arsenic adsorption characteristic, by using IOCC was conducted to column test. As a result, PIOPC is showed a high arsenic adsorption amount than IOPC, it was found that the time required to reach the breakthrough point is also extended. Therefore it is determined that stably compliance with water quality standards enhanced drinking water when using the PIOPC.

• Journal of Soil and Groundwater Environment
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• v.6 no.3
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• pp.43-52
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• 2001

It is important that the gas collected from wells completed in waste landfill should be continuously and stably transported to pre-treatment stage through pipelines. The transport is generally affected by fluid flow characteristics of landfill, gas reserves, leachate moisture holdup in pipeline, structures and dimensions of pipeline network, etc. This paper analyzes the pipeline transport and collection mechanism for gas generated in a durable waste landfill. From the results, the optimal controlled scheme of blower inlet pressure is proposed for the prevention of trapped gas pocket zones.

• Journal of Soil and Groundwater Environment
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• v.17 no.4
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• pp.19-26
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• 2012

The influence of operation time on electrokinetic restoration was investigated to remove salts from sulfate-accumulated greenhouse soil. Operation time is directly related to the process cost, therefore, we determined the relationship between operation time and removal of salts. Nitrate and sodium were removed almost completely within 2 weeks, chloride and calcium was removed in proportion to the operation time. Sulfate was accumulated at the center of anode and cathode. The soil electrical conductivity (EC), an indicator for soil salinity, showed similar shape with the residual sulfate after electrokinetic treatment. The soil EC was not changed after 2 weeks, however, the energy consumption increased with operation time. Based on the experimental results, most salts except sulfate were removed within 2 weeks, but sulfate was not removed during same time period. For the further removal of sulfate, longer operation time is in need.

• Membrane and Water Treatment
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• v.14 no.2
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• pp.95-106
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• 2023

In the developing country like India, groundwater is the main sources for household, irrigation and industrial use. Its contamination poses hydro-geological and environmental concern. The hazardous waste sites such as landfills can lead to contamination of ground water. The contaminants existing at such sites can eventually find ingress down through the soil and into the groundwater in case of leakage. It is necessary to understand the process of migration of pollutants through sub-surface porous medium for avoiding health risks. On this backdrop, the present paper investigates the behavior of pollutants' migration through porous media. The laboratory experiments were carried out on a soil-column model that represents porous media. Two different types of soils (standard sand and red soil) were considered as the media. Further, two different solutes, i.e., non-reactive and reactive, were used. The experimental results are simulated through numerical modeling. The percentage variation in the experimental and numerical results is found to be in the range of 0.75- 11.23 % and 0.84 - 1.26% in case of standard sand and red soil, respectively. While a close agreement is observed in most of the breakthrough curves obtained experimentally and numerically, good agreement is seen in either result in one case.

• Journal of Soil and Groundwater Environment
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• v.28 no.6
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• pp.16-23
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• 2023

Heavy metal (Zinc, Cadmium, Lead) adsorption onto surface modified activated carbon was performed in order to better understand the effect of sodium ion addition to activated carbon. Surface modification methods in this research included water washing, nitric acid washing, and sodium addition after nitric acid washing. These surface modifications generated oxygen functional groups with sodium ions on the surface of the activated carbon.. This caused the change of the specific surface area as well as in the ratio of the carboxyl groups. Heavy metal adsorption onto sodium-containing activated carbon was the most among the three modifications. After the adsorption of heavy metals, the carboxyl group ratio decreased and sodium ions on the surface of the activated carbon were almost non-existent after the adsorption of heavy metals onto sodium-containing activated carbon. The results from this research indicated that ion exchange with sodium ions in carboxyl groups effectively improved heavy metal adsorption rather than electrostatic adsorption and hydrogen ion exchange.

• Journal of Soil and Groundwater Environment
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• v.29 no.2
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• pp.1-10
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• 2024

With industrial development, the inevitable increase in both organic and inorganic waste necessitates the exploration of waste treatment and utilization methods. This study focuses on co-pyrolyzing lignin and red mud to generate metalbiochar, aiming to demonstrate their potential as effective adsorbents for water pollutant removal. Thermogravimetric analysis revealed mass loss of lignin below 660℃, with additional mass loss occurring (>660℃) due to the phase change of metals (i.e., Fe) in red mud. Characterization of the metal-biochar indicated porous structure embedded with zero-valent iron/magnetite and specific functional groups. The adsorption experiments with 2,4-dichlorophenol and Cd(II) revealed the removal efficiency of the two pollutants reached its maximum at the initial pH of 2.8. These findings suggest that copyrolysis of lignin and red mud can transform waste into valuable materials, serving as effective adsorbents for diverse water pollutants.

• Journal of Soil and Groundwater Environment
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• v.17 no.6
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• pp.102-111
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• 2012

Fine suspended solids generated effluence from treatment process of mine drainage could destroy environment as the aesthetic landscapes, and depreciate water quality. Therefore, the purpose of this research is focused on process development applied the actual field for controlling fine suspended solids and heavy metals, and so lab-scale test was performed for inducement of basic data. The mine drainage used in this research was sampled in H mine located Jeongseon-gun, Gangwon-do. Concentration of suspended solid, arsenic, iron and manganese was exceeded the standard of contaminant limitation for the clean water, and particle size of suspended solid was less than 10 m as fine particle. Although hydraulic retention time of mine drainage for effective settling was required more than 6 hours, hydraulic retention time would be increased in winter season when the settling efficiency could be reduced because of viscosity decreasing. Moreover, installed inclination plate helped to increase settling efficiency of suspended solid about 48 %. Filtering media that was the most effective removal of suspended solids and heavy metal was decided granular activated carbon of 1~2 mm was the optimal size.