• International Journal of Advanced Culture Technology
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• v.12 no.2
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• pp.334-344
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• 2024

In Dangjin, Chungcheongnam-do, there are not only power plants and large steel complexes, but also small and medium-sized air pollutant emission facilities. The dust generated by these facilities has a very small particle size and a large surface area due to condensation and physical and chemical reactions, and is discharged containing various harmful substances. Therefore, this study analyzed the distribution of particulate matter and heavy metal concentrations by particle size in the vicinity of the steel complex, residential area, and reference point using an eight-stage Cascade Impactor. Overall, the direct impact sites with a short distance from the steel complex had the highest concentration, followed by the indirect impact sites, and the non-impact sites had the lowest concentration, indicating that they are directly affected by the steel complex. The atmospheric dust concentration distribution showed a bimodal distribution with a minimum value around the 1.1 to 2.1 ㎛ particle diameter. However, during the yellow dust event, the maximum concentration was biased toward coarse particles. The proportion of PM2.5 in the dust tended to be higher in winter, while the ratio between PM2.5 and PM10 was relatively higher in spring. Regardless of the location of the impact point, heavy metals in the dust were dominated by iron and aluminum, followed by zinc, lead, and manganese.

• Journal of Environmental Science International
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• v.1 no.1
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• pp.89-96
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• 1992

In this study , we have investigated leaching characteristics of heavy metals and alkalinity centering around steel mill slags by several extraction methods, for the purpose of risk assessment that exert influence on environment and offer of the foundation data of reuse by slags. Korean standard method, U.S.EPA Extraction Procedure, alkalinity extraction test and 9 step sequential fractionation experiment by Miller et al. were carried out for investigating teachability of steel mill slags. As a result of this experiment, heavy metals were little detected and it was considered that alkalinity does not exert a bad effect around environment in slabs with large particle size. By the result of 9 step fractionation experiment, heavy metal contents in slags were not plentiful, in addition, even comparatively plentiful contended heavy metals, for the most part, were likely to detained or bonded in silica matrix. Therefore, in case of slags with large particle size, it seems that teachability of heavy metals were next to impossible that is existed as a safety condition.

• Resources Recycling
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• v.10 no.4
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• pp.48-57
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• 2001

The main consistent materials and main elements of the bottom ash in municipal solid waste incineration ash according to particle size were investigated and the environmental hazards were considered by investigating the content of dioxin and heavy metals in bottom ash and the concentration of heavy metals in its leachate. The main materials of bottom ash are glasses, ceramics, scraps of iron. As the particle size increases, their percentage weight also increases and their percentage weight was over 70% in 4 mesh~25 mm particle size fraction. The main elements of bottom ash are CaO, $SiO_2$, $Fe_2$$O_3$,$ A1_2$$O_3$and the content of CaO decreases and the content of $SiO_2$increases as particle size increases. The heavy metals accumulate in small particle size fraction. The concentration of heavy metals in each leachate by domestic leaching test is almost similar. As the aging period is prolonged, pH of bottom ash lowers gradually and the leached concentration of Cu and Pb diminishes.

• Particle and aerosol research
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• v.17 no.4
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• pp.133-148
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• 2021

This study aims to estimate the amount of air pollutants emitted from heavy industry facilities in North Korea. To compare the emission in 2017 from the heavy industry sector in North Korea with South Korea, the heavy industry sector was classified with the South Korean classification (Matching Heavy Industry sector) and air pollutant emissions by Matching Heavy Industry sector in North Korea were estimated. The CO, NO_x and SO_x emissions of Matching Heavy Industry sector in North Korea are 22%, 73%, and 31% of the emission in South Korea, respectively. The air pollutant emissions in the Matching Heavy Industry sector in North Korea for CO, NO_x and SO_x were 0.6%, 124%, and 24% of the total air pollutant emission in North Korea estimated from EDGAR, respectively. As for the distribution of emissions by administrative district of the Matching Heavy Industry sector in North Korea, NO_x was concentrated in the western part of North Korea, and CO and SO_x emissions were concentrated in Hamgyong-bukto.

• The Korean Journal of Food And Nutrition
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• v.9 no.3
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• pp.307-313
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• 1996

The study was performed under the various conditions, such as the edible parts and particle sizes of Allium, the concentrations, the temperatures, and the pH of heavy metal solutions to investigate their adsorption capacity of heavy metals by genus Allium. The adsorption amount of Cd by Allium in the aqueous solution was apparently higher than that of Zn by them. The larger the particle size of welsh onion and shallot was, the higher the adsorption of Cd was. But the adsorption ratio was not different. As the temperature increased, the amount of heavy metal adsorption increased in general, but the adsorption of Cd by wild garlic, Zn by garlic decreased. Adsorption of Cd and Zn to Allium was not affected by the various pH. The correlation between the amount of components in edible putts of Allium and that of adsorption of heavy metals was significantly high in amino acids containing sulfhydryl radical (-SH) and vitamin B2.

• Journal of the East Asian Society of Dietary Life
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• v.9 no.3
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• pp.363-369
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• 1999

The heavy metal removability of four kinds of tea was investigated in the various conditions: particle size of tea(10, 35. 70, 100 mesh), concentration of heavy metal(25, 50, 100ppm) and extraction temperature(30. 50, 70. 10$0^{\circ}C$). The removabilities by the tea solids were increased as the particle size decreased, concentration of heavy metal increased, and extracting temperature increased. Of the four kinds of tea Pb, Cd and Cu removability by Eucommia ulmoides Oliv tea was the highest. In addition, heavy metal removability by Schizandra chinensis Baillon tea was better than that of other tea as extraction temperature was increased.

• Progress in Medical Physics
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• v.8 no.1
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• pp.47-52
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• 1997

Simulations were performed using a Monte Carlo technique in order to show physical phenomena occurring when a heavy charged particle such as proton or alpha particle traverses the medium. It was confirmed that the sharp Bragg peak occurred deeper in the water with the increasing proton energy. It is found that the use of such a sharp Bragg peak due to heavy charged particles would be far superior to the case of the photon or electron, since the absorbed dose in the target tissues would be better localized, thereby minimizing the damage to the surrounding tissues.

• Journal of Korean Society for Atmospheric Environment
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• v.20 no.2
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• pp.225-236
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• 2004

Diesel engines which emit a lot of PM and NOx have been known as a main air polluter. Especially, diesel particulate matters (OPM) including black smoke are hazardous air pollutants to human health and environment. The nations retaining advanced engine technologies have reinforced emission regulations. To meet these regulations diesel engine manufacturers have developed low-emission diesel engines, aftertreatment equipments, alternative fuel technologies and so on. In this study, particle number concentrations characteristics according to particle size and engine driving conditions were analyzed when these low-emission technologies were applied. There was a tendency of increasing particle number concentrations from heavy-duty diesel engines with increasing engine rpm and load rate. In the cases of COPF (Catalytic Diesel Particulate Filter), CNG (Compressed Natural Gas) engine and ULSD (Ultra Low Sulfur Diesel) more than 99% of particle number concentration were removed.

• Journal of the Korean Society of Marine Environment & Safety
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• v.14 no.4
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• pp.247-256
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• 2008

For the systematic scientific management of tidal flat sediment in Julpo bay of Korea, this study conducted a survey of particle composition, organic matter(l.L) and heavy metals for three lines ; including F, R and L lines in tidal flat sediment. Particle composition of tidal flat sediments consisted predominantly of clay at F line which was in right angle direction to the coast, whereas R and L lines were located horizontally along the coast and consisted predominantly of silt. Mean grain size values of tidal flat sediments were in the range of 3.7 ${\phi}{\sim}$10.4 ${\phi}$(average 7${\phi}$). The contents of heavy metals observed at R and L lines were lower than those at F line. The correlation analysis among heavy metals, organic matter and particle size was found to have a good interrelationship. For the evaluation of heavy metals pollution, two criteria of US NOAA and KEI(in Korea) were applied Heavy metals pollution level of tidal flat sediments belonged in Non polluted and Moderately polluted groups in US EPA criteria, and its pollution levels sat below ERL in NOAA criteria. The results of heavy metals pollution level obtained by KEI criteria were found to be less than the goal level.

• 한국신재생에너지학회:학술대회논문집
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• 2010.11a
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• pp.199.2-199.2
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• 2010

Biodiesels are well-known as alternative fuels. also we know that biodiesels increase NOx and reduce PM(Particulate Matter) by previous many studies. But PM in most these studies was considered about the mass. In this study, We have performed experimental test for PM and exhaust emission by mixed ratio of biodiesel in heavy duty diesel engine. PM was investigated by The nano particle number and the mass. The mass of PM was evaluated by using the standard gravimetric method, The number of PM was evaluated by using the EEPS(Engine Exhaust Particle Sizer), on the ESC(European Steady Cycle) mode. Sampled gas through dilutor was directly extracted from tail pipe and EEPS measured diluted exhaust gas. Biodiesel is made up of used cooking oil. Diesel as base fuel was sold on market and contains 2% biodiesel. The mass of PM was reduced 10% and the nano particle number was increased 5%. The particle number less than 40nm was increased, but the particle number more than 40nm is decreased.