• International Journal of Highway Engineering
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• v.13 no.2
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• pp.187-193
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• 2011

The stormwater runoff from road or expressway is known as one of important nonpoint pollution sources. To reduce the pollutants discharge from road or expressway, many best management practices(BMPs) have been applied and planned. Among the BMPs, road sweeping can be effective way to prevent pollutant washoff to environment. This study is performed to evaluate the characteristics of particles collected from the road by sweeping car. Size distribution and pollutant concentration of particles were analyzed. Based on the pollutant concentration and the specification of road such as length, width, and unit for pollutant generation, total amount of pollutant to be removed by road sweeping was estimated. Most of sediments collected by road sweeping was classified into sandy soil and fraction of fine grained soil was low. Although the concentrations of pollutants such as heavy metals in road sediments did not exceed the soil contamination criteria, washout of pollutants during sweeping work by spraying water might cause leaching of pollutants contained in sediments and thus resulted in low pollutant concentrations. Reduced amounts of pollutant by road sweeping showed 31.4% TSS reduction for ${\bigcirc}{\bigcirc}$ region and 7.7% TSS for ${\triangle}{\triangle}$ region. Other pollutants showed low reduction rate, because of their leaching by water spraying. Results from this study indicate that detailed and well-planned investigation for the road sweeping is necessary for the accurate estimation of pollutant reduction from road or expressway.

• Journal of Korean Society for Atmospheric Environment
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• v.27 no.3
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• pp.303-312
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• 2011

Data on the energy usage including biomass, emissions of air pollutants ($SO_x$, $NO_x$, CO), and the air quality in North Korea are analyzed. The energy usage in North Korea has decreased in the 1990s and thus, the emission amount of air pollutants. Coal and biomass constitute a major fraction of energy sources since the 1990s. It is identified that the emission amount of air pollutants per unit energy consumption in North Korea is much higher than South Korea for the period data are available (since 1990) implying that the air pollutant emission management system in North Korea is inadequate. In particular, the amount of biomass burning for household cooking and heating is significant with the huge emissions of air pollutants such as CO and organic species both in the gas and aerosol phase. Furthermore, it is found that the existing energy usage and air pollutant emission data are not consistent in biomass burning related data.

• Journal of environmental and Sanitary engineering
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• v.21 no.4 s.62
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• pp.77-86
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• 2006

The water purification was very important in Korea which has not sufficient water resource and while adsorption method among the various methods to eliminate the water pollutants has been widely used by activated carbon. This study was conducted the basic experiment for hall distribution, pH, conductivity, electronic microscope, cation exchange and inorganic materials the adsorption capacity of Korean traditional charcoal which has similar characteristics to activated carbon of organic pollutants. As a result of observing Korean traditional charcoal with electronic microscope, it was found that it has porous structure, oak charcoal has circular structure, pine charcoal has square structure and bamboo charcoal has hexagonal structure, which has high void fraction per unit area because of its thin cell wall structure. As a result of experimenting hall distribution, hall distribution of bamboo high temperature charcoal is high as 0.269cc/g and has the greatest inorganic contents and cation exchange capacity(CEC) which are the important factor of chemical adsorption.

• Journal of Preventive Medicine and Public Health
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• v.21 no.2 s.24
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• pp.284-294
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• 1988

To measure the mutagenic activity of micro-organic pollutants in drinking water, mutagenicity test was conducted using Salmnella typhimurium TA 98 strain on the water sample taken from three water supply stations and six tap water in Seoul in July and November 1987. The results were as follows : 1. The average amounts of organic matters in raw, treated, and tap water sampled in July were 0.38mg/l, 0.28mg/l, and 0.45mg/l. respectively, and sampled in November were 0.34mg/l, 0.24mg/l, and 0.22mg/l, respectively. The amount of organic matters of tap water sampled in November did not increase while that of tap water sampled in July increased compare to those of raw or treated water. 2. The amount of organic matters is the highest in neutral fraction compare to acidic and basic fractions. 3. In the five out of six tap water and raw water of Paldang and Kuui station sampled in July, the mutagenicity ratios were greater then two (both direct and indirect mutagenicity). 4. In the three out of six tap water and raw and treated water of Kuui station sampled in November, the mutagenicity ratios were greater than two. 5. While mutagenic activities were low in acidic and basic fraction, they were high in neutral fraction. The samples which had high mutagenic acitivity in the total amount also showed high mutagenic activity in neutral fraction. 6. While mutagenic acitivity was decreased after the treatement of water, it was increased in tap water as the distance from the water supply station increases.

• Environmental Mutagens and Carcinogens
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• v.15 no.2
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• pp.131-139
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• 1995

Air suspedned particulates are the most serious factor among air pollutants in Seoul and their extracts have been revealed to be pulmonary carcinogenes. Air particulates were collected at a site representative of the high traffic area of Seoul from December 1993 to May 1994. Polycyclic aromatic hydrocarbons (PAHs) and nitroarenes in organic extracts of air particulates were determined by gas chromatography and mutagenicity of particle extracts was evaluated by the pre-incubation procedure with Salmonella typhirnurium TA98 and TA 98NR. The average concentration of total suspended particulates and inhalable (less than 10 $\mu$m) particulates were 169.63 $\mu g/m^3$, 141.92 $\mu g/m^3$, respectively. The relative contribution of organic matters was highest in neutral fraction and was lowest in basic fraction. Among identified 20 PAHs, the level of PAHs with 4-benzen ring i.e., pyrene, benzo(a)anthracene and chrysene were much higher than the PAHs with higher ring numbers. The mutagenicity of air particulates was much higher in the presence of rat liver microsomai fraction (S9 mixture) than that observed in its absence, which indicates that air particulates contained both direct and indirect mutagens. Nitroarenes in this study were not almost detected but mutagenicity of their fraction was higher. These results are represent to research for the identification of nitroarenes in the forward study.

• Applied Chemistry for Engineering
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• v.8 no.3
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• pp.517-523
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• 1997

We have been studied that combustion efficiency and the production of air pollution of anthracite-bituminous coal blend in a fluidized bed coal combustor. Also, the reaching time of steady state condition have been studied. This experimental results are presented as follows. As the height of fluidized bed combustor becomes higher, the concentrations of $SO_2$ and NOx mainly increased. Also, as anthracite fraction increased, the emission of $SO_2$ concentration was increased but, the variation of $NO_X$ concentration was negligible according to anthracite fraction. When anthracite fraction ratio was increased, elutriation rate was increased and exit combustible content over feeding combustible content was increased. Regardless of anthracite fraction ratio the uncombustible weight percentage according to average diameter of elutriation particles were approximately high in the case of fine particles. Over bed temperature $850^{\circ}C$ and excess air 20%, the difference of combution at the velocity 0.3m/s, bed temperature $850^{\circ}C$, the excess air 20%.

• Economic and Environmental Geology
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• v.27 no.5
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• pp.469-477
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• 1994

Many researchers have investigated most representative sequential extraction method using various reagents for determining the chemical forms of metals in soils and sediments. In this paper, a newly modified method for sequential extraction scheme based on Tessier's method by Environmental Geochemistry Research, Centre for Environmental Technology, Imperial College, was introduced and examined. In comparison with Tessier's method, originally designed for sediment analysis by Atomic Absorption Spectrophotometry (AAS), the sequential extraction scheme has been developed for the multi-element analysis by Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES). The partitioning of particulate trace elements was classified into five fractions: (i) exchangeable, (ii) bound to carbonates or specially adsorbed, (iii) bound to Fe and Mn oxides, (iv) bound to organic matter and sulphides and (v) residuals. The experimental results of the pilot study for in-house reference material (HRM2) and certified international standard reference material (SRM2711) using the modified method showed not only reasonable precision and accuracy but also acceptable overall recovery rates. In addition, mine dump soils sampled in the Dalsung Cu-W mine, Korea were prepared and sequentially extracted using the method. Most of Cu was bound to organic matter/sulphides and residual fractions. The dominant fraction of soil Pb and Zn in the study area was found in the residuals. The fraction of Cd showed a wide variation between samples and could be found bound to the carbonates or specially adsorbed, oxides, organic fraction and residuals. The recovery rates of Cd, however, were poor due to relatively low Cd concentrations in soils. The heavy metals in these mine dumps appear to be in the more inert forms and should not be readily bioavailable. The soils, however, had very low pH values (average 4.1) and had sandy textures; consequently, rapid infiltration of rainfall may increase leaching of Zn and Cd which were found to be around 5 to 10% of the exchangeable fraction. As a result of the investigation of this study, it has been strongly recommended that these mine waste materials should still be considered a significant contaminant source and will need environmental remediation to prevent pollutants from being released into the environment.

• Environmental Analysis Health and Toxicology
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• v.5 no.3_4
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• pp.19-28
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• 1990

Nitroarenes are ubiquitous environmental pollutants displaying potent mutagenicity in bacteria and carcinogenicity in mammal. In this study, the concentration of nitroarenes in coarse and fine particles and mutagenicity of POC$\_$N/ fraction was investigated in suspended particulates at the Shinchon and Bulkwang area of Seoul. The suspended particulates were collected bimonthly by a high volume cascade impactor air sampler from July 1987 to May 1988. Extractable organic matter was obtained by ultrasonic extraction on diethly ether/cyclohexane (8/2, v/v). Neutral fraction was obtained by liquid-liquid extraction. Polar neutral organic compounds (POC$\_$N/) was fractionated by thin-layer chromatography. Finally, the concentrations of nitroarenes in POC$\_$N/ fraction were measured and determined by capillary gas chromatography. Direct and indirect mutagenicity of POC$\_$N/ fraction were measured using Salmonella typhimurium TA 98. The result were as follows: 1) Major nitroarenes at the Shinchon area was 1-nitropyrene and at the Bulkwang area it was 2,7-dinitro-9-fluorenone during the year. 2) Average concentration of total nitroarenes measured was 67.26 ng/m$^3$in fine particles which was 1,3 folds higher that in coarse particle (52.30 ng/m$^3$). 3) Annual pattern of nitroarenes concentrations revealed that concentration during heating season (Feb., Jan., Mar.) was 2.2 folds higher than that in non heating season (May, Jul., Sep.). Concentration of each season has 157.68 ng/m$^3$and 80.39 ng/m$^3$. 4) The mutagenic activity of POC$\_$N/ fraction from fine particles was higher compared to that of coarse particles and was increased when metabolically activated, with 59 mixture. Mutagenicities, Metabolically activated, were significantly different between Shinchon and Bulkwang area, 322.8 rev/250 $\mu\textrm{g}$/plate and 286.8 rev/250 $\mu\textrm{g}$/plate, respectively. 5) Annual pattern of mutagenicity of POC$\_$N/ fraction revealed that mutagenicity during the heating season was 1.7 folds higher at Shinchon area and 1.2 folds higher at Bulkwang than during the non heating season. The variable contents and levels of nitroarenes in suspended particulates may affect human health significantly. Further studies such as risk assessment should be conducted on the basis of these kind of studies.

• Journal of Navigation and Port Research
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• v.39 no.4
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• pp.345-351
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• 2015

This study investigated the optimum depth for the application of bioremediation in contaminated coastal sediment using a lab scale column experiment. The biostimulants were placed in the top surface of the sediment facing seawater, 3cm, 6cm and 10cm of the depth from the surface, respectibely. During the experiment, the changes of organic pollutants and heavy metal fractions in the sediment were monitored in 1 month and 3month time intervals. The organic pollutants found during various analysis such as chemical oxygen demand, total solids and volatile solids, significantly reduced when the depth of the biostimulant was 3cm or less. In contrast, at a depth of over 6cm, the reduction of organic pollutants decreased, and the results were similar to the control. Heavy metals fractions in the sediment also changed with the depth of the biostimulants. The exchangeable fraction of the metals was quite reduced at the sediment surface in the column, but the organic bound and residual fractions considerably increased at a depth of 3cm. Based on this study, the optimum biostimulants depth for in-situ bioremediation of contaminant coastal sediment is 3cm from the sediment surface.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.8 no.4
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• pp.13-18
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• 1999

Recently among after-treatment devices which have high possibility of utility diesel oxidation catalyst(DOC) is concerned over the world. DOC oxidizes pollutants by means of activate-reaction during by-passing in the catalyst in doing so conversion efficiency of PM, CO and HC is high and this device does not have an effect on engine performance because back pressure is not nearly increased, But as a small amount of sulfur content in fuel is oxidized it makes sulfate which is absorbed on the surface of catalyst. So in this study the experiment is carried out by means of using ordinary fuel(0.1wt%) and low sulfur fuel(0.05wt%) with DOC and the emission gas of diesel engine is measured.