• Journal of Soil and Groundwater Environment
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• v.6 no.4
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• pp.41-50
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• 2001

The use of clay has been the favored method of reducing or eliminating hazardous contaminants in the leachate from landfills. But, neither natural clays nor organoclays modified with surfactants are able to effectively sorb both heavy metals and organic contaminants. Therefore, the objective of this study is to determine the optimal amount of surfactant added on the clay mineral to effectively remove both of them. For this purpose, Na-Bentonite as the natural clay, and hexadecyltrimethylammonium (HDTMA) as the cationic surfactant were used, Chlorobenzene and lead ($Pb^{2-}$) were selected as representative contaminants. Experimental result showed that chlorobenzene sorption increased with increasing HDTMA to bentonite, ratios. On the contrary, the removal rate of lead decreased as the amount of HDTMA increased. The removal of chlorobenzene was influenced by the amount of HDTMA added to the bentonites rather than initial concentration of chlorobenzene, but the removal of lead was much more influenced by the initial concentration of lead. The adsorption of lead was not affected by chlorobenzene, and vice versa. The competitive sorption between the heavy metal and the organic contaminant was not present.

• Korean Journal of Food Science and Technology
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• v.18 no.4
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• pp.264-269
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• 1986

This study was undertaken to investigate the removal efficiency of heavy metals (Cd, Pb) in rice and wheat flour by cooking and processing. After four times washing of rice grains with water, the removal ratios of cadmium and lead from artificially-contaminated samples were 39.271 and 34.9%, respectively. In cookingof rice grains washed three-times with water, the residue levels of cadmium and lead decreased to 85.7%, 83.0% in electric rice cooker and 74.51%, 72.6% in pressure rice cooker, respectively. No significant difference was observed in the removal of the metals between naturally-contaminated and artificially contaminated rice samples, and between the electric and pressure rice cookers. In baking of artificially-contaminated wheat flour into cookie and loaf bread, the removal ratios of cadmium and lead were negligible as expected. When knife-cut noodle was made from artificially-contaminated wheat flour and boiled in water, 75% of the metals were found in the noodle solids and only 25% of them were removed into the broth.

• Journal of Environmental Health Sciences
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• v.32 no.1 s.88
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• pp.8-18
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• 2006

The aim of this study is to evaluate the emission characteristics of mercury, lead, arsenic, and selenium from medium size municipal solid waste incinerators(MSWIs) in Korea. The concentrations of mercury, lead, arsenic, and selenium emitted from medium size MSWI stack were $2.67\;{\mu}g/Sm^3,\;0.38\;mg/Sm^3,\;1.33\;{\mu}g/Sm^3,\;0.28\;{\mu}g/Sm^3$, respectively. The concentration levels of mercury, lead, arsenic in flue gas from medium size MSW incinerator stacks selected were nearly detected under the Korea criteria level. Removal efficiencies of mercury, lead, arsenic, and selenium in waste heat boiler(WHE) and cooling tower(CT) were $90.36\%,\;69.76\%,\;43.04\%,\;40.64\%$, respectively. In general, the removal efficiencies of mercury and lead in WHE were higher than those of arsenic and selenium in WHE. Emission gas temperature reduction from waste heat boiler(WHB) and cooling tower(CT) can control mercury and lead of medium size MSWIs. To evaluate the relationship between mercury, lead, arsenic, selenium of fly ash and those of flue gas, it was carried out to correlation analysis of each metal concentration in the fly ash and in the flue gas from medium size MSWIs. From the correlation analysis, the coefficients of mercury, lead, arsenic, and selenium were 0.61, -0.38, 0.87, 0.28, respectively. The results of correlation analysis revealed that it should be highly positive to the correlation coefficients of mercury and arsenic in the fly ash and those of the flue gas emitted from medium size MSWIs. As it were, the concentrations of mercury and arsenic of flue gas from medium size MSWIs are high unless mercury and arsenic in fly ash are properly controlled in dust collection step in medium size MSWIs. It was also concluded that mercury, lead, arsenic, and selenium from MSWIs stacks could be controlled by waste heat boiler(WHE) and dust collecting step in medium size MSWIs.

• Geotechnical Engineering
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• v.13 no.6
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• pp.123-138
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• 1997

Electroosmotic tests were performed on saturated marine clay specimens contaminated with lead to investigate the efficiency of the electrokinetic technique for removal of heavy metals from the cohesive soils. For this purpose, testing program included variable conditions such as the concentration of lead (500, 5, 000, 50, 000mg/kg), the level of electrical current (10, 50, 100 mA), operating duration (5, 15, 30days), and the application of three dirtferent chemicals for enhancement in efficiency. The pH of inflow and outflow, electroosmotic flow and electrical conductivity during the test, and the pH and the concentration of lead across the specimen after the test are presented. Test results came to the conclusion that the electrokinetic technique was very effective to remove heavy metals such as lead from the contaminated cohesive soil. Adding ecetic acid at the cathod to dissolve the procipitates of lead hydroxide as found to be effective for the enhancement of the efficiency in remediation.

• Journal of Korean Society of Water and Wastewater
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• v.25 no.3
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• pp.359-366
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• 2011

The feasibility of using volcanic ash for lead ion removal from wastewater was evaluated. The adsorption experiments were carried out in batch tests using volcanic ash that was treated with either NaOH or HCl prior to the use. Volcanic ash dose, temperature and initial Pb(II) concentration were chosen as 3 operational variables for a $2^3$ factorial design. Ash dose and concentration were found to be significant factors affecting Pb(II) adsorption. The removal of Pb(II) was enhanced with increasing volcanic ash dose and with decreasing the initial Pb(II) concentration. Pb(II) adsorption on the volcanic ash surface was spontaneous reaction and favored at high temperatures. Calculation of Gibb's free energy indicated that the adsorption was endothermic reaction. The equilibrium parameters were determined by fitting the Langmuir and Freundlich isotherms, and Langmuir model better fitted to the data than Freundlich model. BTV(base-treated volcanic ash) showed the maximum adsorption capacity($Q_{max}$) of 47.39mg/g. A pseudo second-order kinetic model was fitted to the data and the calculated $q_e$ values from the kinetic model were found close to the values obtained from the equilibrium experiments. The results of this study provided useful information about the adsorption characteristics of volcanic ash for Pb(II) removal from aqueous solution.

• Journal of the Korean GEO-environmental Society
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• v.3 no.4
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• pp.5-10
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• 2002

Pistia stratiotes(Water Lettuce) can be applied to remove inorganic pollutants from the wastewater for the advanced treatment. This study attempts to remove heavy metals from the secondary treated wastewater. Three different initial concentrations of heavy metals were applied as 0.5, 1.0 and 1.5 mg/L for Lead(Pb) and Chromium(Cr(VI)). In addition, the removal efficiency for the mixture of Lead and Chromium was also observed. The removal efficiency of Pb was in the range of 41.0~72.0% for Pb and it was in the range of 25.0~30.0% for Cr(VI) by Pistia stratiotes. The plants placed in static systems were able to remove the heavy metals in a few days of exposure. However, it was observed that the heavy metals affected produce phytotoxic effects on plants resulting in inhibition of chlorophyl synthesis, decrease in biomass production, and finally plant necrosis. The removal efficiencies of Pb and Cr(VI) by Pistia stratiotes were increased with plant growth.

• Journal of Chest Surgery
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• v.32 no.7
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• pp.668-670
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• 1999

The most important indication for the removal of the lead-electrode system is the presence of an infection. When an infection occurs, the entire pacemaker system including the impluse generator and lead-electrode system should be removed. The entrapped electrode can be removed by a continous traction, by the use of forceps, snares or baskets, by the use of a locking stylet or a dilator sheath, and by an operation. We report a case that underwent a removal of an entrapped transvenous pacemaker electrode by the use of snaring technique.

• Journal of Soil and Groundwater Environment
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• v.18 no.7
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• pp.1-11
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• 2013

The actively soil pollution by the toxic heavy-metals like the arsenic, cadmium, lead due to the industrialization and economic activity. The uses the electrokinetic remediation of contaminated soil has many researches against the fine soil having a small size in the on going. However, it is the actual condition which the research result that is not effective due to the low surface charge of the particle and high permeability shows in the electrokinetic remediation in comparison with the fine soil in the case of the sandy soil in which the particle size is large. In this research, the electrokinetic remediation and ultrasonic wave fetch strategy is compound applied against the sandy soil polluted by the arsenic, cadmium, and lead removal efficiency of the sandy soil through the comparison with the existing electrokinetic remediation tries to be evaluated. First of all, desorption of contaminants in soil by ultrasonic extraction in the Pre-Test conducted to see desorption effective 5~15%. After that, By conducted Batch-Test results frequency output century 200 Khz, reaction time 30 min, contaminated soil used in experiment was 500 g. Removal efficiency of arsenic, cadmium, lead are 25.55%, 8.01%, 34.90%. But, As, Cd, Pb remediation efficiency less than 1% in EK1(control group).

• 한국생물공학회:학술대회논문집
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• 2005.04a
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• pp.252-256
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• 2005

Removal of heavy metal ions from aqueous solution by brown sea weeds (Hizikia fusiformis, Laminaria, and Undaria pinnatifida) was 80-96% for lead, cadmium, chromium and copper ions. Fifty percent of the adsorption was completed in 4 min. The uptake of lead and cadmium ions followed Langmuir adsorption. In the adsorption experiments using single and multi metal ions 80-95% of metal ions were removed, and the removal efficiency was the best for lead ion.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2002.04a
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• pp.44-48
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• 2002

Washing technique using solubilization and surfactant as a extractant was studied by removing contaminants from the cohesive soil contaminated with heavy metal. For this purpose, the laboratory desorption batch tests were peformed in the kaolinite contaminated with lead by using acetic acid as a solubilization and SDS as a anionic surfactant. In desorption batch tests, the effects of extractant concentration and mixing ratio were investigated and also the coupling effects of acetic acid added with surfactant were considered. Test results show that the removal efficiency of acetic acid as a extractant in the kaolinite contaminated with lead increased with increasing the concentration of acetic acid and the acetic acid was found to be more effective when adding CMC 2 or 3 of surfactant. Additionally, regardless of the initial concentration, the efficiency of lead removal from the contaminated soil increased with increasing shaking ratio.