• Proceedings of the Korean Institute of Building Construction Conference
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• 2021.05a
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• pp.116-117
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• 2021

This study examined basic mechanical properties by developing eco-friendly soil concrete using Masato particulate matter treated as waste. Experiments show that DG10 satisfies the compressive strength criterion, but for DG20, the criterion was not reached. As the mixing volume of Masato particulates increased, the compressive strength and slump decreased, and in the case of the compression strength test after freezing and melting, it was found that the standards were not met.

• Journal of the Korean GEO-environmental Society
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• v.14 no.11
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• pp.25-31
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• 2013

Civil and military firing ranges are usually contaminated with heavy metals such as lead and copper and remediation is required. Acid washing and extraction are common remediation methods. Lead contaminated firing range soil samples were collected and a preliminary study was conducted to evaluate the characteristics of the contamination and the contribution of high specific gravity particles. Ethylenediamine tetra acetic acid(EDTA) extraction was applied for the removal of heavy metal but the extraction was not feasible for the firing range soil. Even after the repeated EDTA extraction, the contamination were still over the Korean environmental standard indicating that soil particles highly contaminated with heavy metal which release the heavy metal ion even after the repeated extraction. Some colored and higher specific gravity particles were separated from the soil samples and analyzed. The colored particles have specific gravity of 2.5-6.6. The saturation ratio of Pb and EDTA was 4.9-32%. After removal of these colored particles, the sandy soil showed moderate contamination which can be treated with soil washing. This was proved with the five-level sequential extraction and TCLP tests.

• Journal of Korean Society for Atmospheric Environment
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• v.8 no.1
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• pp.52-57
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• 1992

The influence of soil particles on TSP transported from China contient to Seoul by the Yellow sand phenomenon was investigated from the analytical results of TSP during three years, April 1988 through May 1991. The TSP was collected by a high volume air sampler abour five times a month, and then analyzed by A.A.S. and UV-Visible spectrophotometry. During the Yellow sand phenomenon, the mean concentration of TSP at Seoul was about 578 $\mug/m^3$ and three times higher than that in the ordinary time which was about 194 $\mug/m^3$. The mean contribution of soil particles calculated by Al content to TSP was 28% in the ordinary time, but the degree of contribution jumped to about 60% during the Yellow sand phenomena. The concentration of soil particles transported from China continent to Seoul was estimated to be 175.1 $\mug/m^3$ on an average(104 $\mug/m^3-231 \mug/m^3$).

• Korean Journal of Soil Science and Fertilizer
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• v.5 no.2
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• pp.59-64
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• 1972

The liming effect of the four different siliceous materials with six grades of fineness were investigated in comparison with limestone under the submerged condition for three months, and the alkalinity extracted by 0.07N-EDTA and N-NaOAc solutions were determined to evaluate the neutralizing power of these materials. 1. Fused phosphate took 20 days with finer particles than 60 mesh (Tyler), 34 days with -40+48 mesh particles and 84 days with -20+25 mesh particles to reach the pH 5.5 from pH 4.0 of initial soil pH. These adjusted soil acidities were less 1.0-0.5 unit of pH compared with the pH of particles of limestone. 2. The basic reduction furnace slag increased the pH value to 5.5 in the finer particles than 100 mesh, but the other coarse particles appeared to have slow changes of the soil acidity to pH 4.5-4.7 for the three months. Wollastonite didn't affect the increase of soil pH in coarser particles than 25 mesh whereas other finer particles increased upto pH 4.5-5.0. Blast furnace slag is definitely slower through all sizes of particles. 3. In the relationship between the adjusted soil acidities and alkalinities dissolved in EDTA and NaOAc solution, NaOAc-alkalinity agreed quite closely to the activity of neutralizing value of silicates and limestone containing fineness of particles. The correlation coefficients between the amended soil acidities and NaOAc-alkalinities were stabilized with high significance at the 8 days after water logging and 16 days with the EDTA-alkalinities.

• Korean Journal of Environmental Agriculture
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• v.29 no.4
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• pp.402-407
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• 2010

Zerovalent iron (ZVI) is one of the most commonly used metallic reducing agents for the treatment of toxic contaminants in wastewater. Traditional ZVIs are less effective than nanoscale ZVI (nZVI) due to prolonged reaction time. However, the reactivity can be significantly increased by reducing the size of ZVI particles to nanoscale. In this study, nZVI particles were synthesized under laboratory condition and their efficiency in removing hexavalent chromium (Cr(VI)) from aqueous solutions were compared with commercially available ZVI particles. The results showed that the synthesized nZVI particles (SnZVI) reduced >99% of Cr(VI) at the application rate of 0.2% (w/v), while commercial nZVI (CnZVI) particles resulted in 59.6% removal of Cr(VI) at the same application rate. Scanning electron micrographs (SEM) and energy dispersive spectra (EDS) of the nZVI particles revealed the formation of Fe-Cr hydroxide complex after reaction. Overall, the SnZVI particles can be used in treating chromium contaminated wastewater.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.10 no.1
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• pp.163-172
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• 1990

The filter criteria of geotextiles to prevent excessive loss of fine particles in cohesion-less soils are largely depend on the flow conditions of water in soil/geotextile systems. In the soil/geotextile system under uni-directional flow conditions, it is adequate to retain only the coarse soil fraction because a 'self-induced' soil filter layer may form in cohesionless soil adjacent to the geotextile. In alternating flow conditions, however, a complete soil filter layer within the soil will not form and thus the geotextile pores must be small enough to retain finer particles of the soil to be protected. Based on these concepts, theoretical filtration criteria of geotextiles are developed considering the flow conditions of water. To test the validity of these criteria, laboratory testing was carried out. This indicated that large losses of fine particles would result, especially at high hydraulic gradients, short periods and low vertical loads. The revised filtration criteria are proposed evaluating effect of various design factors.

• Journal of the Korean Society of Clothing and Textiles
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• v.34 no.4
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• pp.653-662
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• 2010

This study investigates the effect of particle size on the detergency of particulate soil using an $\alpha-Fe_2O_3$ particle as the model. Monodispersed spherical $\alpha-Fe_2O_3$ particles were prepared by the hydrothermal aging of an acidic $FeCl_3$ and HCl solution. The $\xi$-potential of PET fiber was measured by the streaming potential method. The potential energy of interaction between the particle and fiber was calculated using the heterocoagulation theory for a sphere-plate model. The $\xi$-potential of PET fiber and potential energy of interaction between particles and fiber increased with a decreasing particle size in a DBS solution. However, in the nonionic surfactant solution, the $\xi$-potential signs of PET fiber and $\alpha-Fe_2O_3$ particles were (-) and (+), respectively; there was no repulsive power between the particles and substrate. The adhesion of particles to the fabric increased with increasing particle size in the anionic surfactant solution and their removal from the fabric increased with a decreasing particle size. The adhesion of particles to the fabric and their removal from the fabric was biphasic with a maximum and minimum at 0.1% concentration of the surfactant solution. In the nonionic surfactant solution the adhesion of particles to fabric and their removal from the fabric were greater than the ones in the anionic surfactant DBS solution.

• Fashion & Textile Research Journal
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• v.4 no.1
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• pp.86-91
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• 2002

To estimate dispersion stability of particles, suspending power and particle size were examined as functions of pHs, surfactants, electrolytes and ionic strengths using ${\alpha}-Fe_2O_3$ particle as the model of particulate soil. Suspending power and particle size were determined by UV-Vis spectrumeter and by light scattering using the polarization ratio method, respectively. The suspending power was relatively high with polyanion electrolytes and was low with neutral salts. The suspending power was biphasis, minimum pH 6~7, and the effect of surfactant on the suspending power was insignificant. Generally suspending power increased with decreasing the particle size governed aggregation of dispersed particles regardless of solution conditions. Hence the suspending power was inversely related to the particle size.

• Proceedings of the Korean Geotechical Society Conference
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• 2003.03a
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• pp.597-604
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• 2003

In the soil washing process, the contaminants are usually removed by abrasion from soil particles using mechanical energy and water However, organic contaminants with low water solubility like polycyclic aromatic hydrocarbons (PAH) are remained on soil particles. Previous studies have shown that surfactant possessing amphipathic activity enhances the solubility of organic materials. For this reason solutions with surfactants have been used to improve removal of organic contaminants on soil washing process. But, in this manner, many problems were found like complete loss of surfactants and additional contamination by surfactant. The remediation method using microemulsion has been introduced to overcome these disadvantages. In this case, surfactants are recycled by phase separation of microemulsion after remediation. In microemulsion process, the surfactant will be recycled by phase separation of the microemulsion into a surfactant-rich aqueous phase and an oil phase after extraction. That is why remediation concept applying microemulsion as washing media has been Introduced. Suitable microemulsion have to be used in order to have the chance of refilling the soil after decontamination and to avoid any risk due to toxicity. The purpose of this research is to evaluate effect of microemulsion to remediation of contaminated soil. We performed test with various organic contaminants like Pyrene and BTEX, also compared efficiency of remediation in microemulsion process with soil washing

• Journal of Soil and Groundwater Environment
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• v.18 no.5
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• pp.56-64
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• 2013

After the law has been enacted for the prevention and recovery of mining damage in 2005, efforts of remediation have been started to recover heavy metal contaminated soils in agricultural land near mining sites. As part of an effort, the upper part of cultivation layer has been treated through covering up with clean soil, but the heavy metal contamination could be still spreaded to the surrounding areas because heavy metals may be remained in the lower part of cultivation layers. In this study, the most frequently occurring arsenic (As) contamination was selected to study in agricultural land nearby an abandoned metal mining site. We applied separation technologies considering the differences in the physical characteristics of soil particles (particle size, density, magnetic properties, hydrophobicity, etc.). Based on physical and chemical properties of arsenic (As) containing particles in agricultural lands nearby mining sites, we applied sieve separation, specific gravity separation, magnetic separation, and flotation separation to remove arsenic (As)-containing particles in the contaminated soil. Results of this study show that the removal efficiency of arsenic (As) were higher in the order of the magnetic separation, flotation separation, specific gravity separation and sieve separation.