• Journal of Environmental Science International
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• v.20 no.5
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• pp.599-610
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• 2011

Emission of air pollutants such as nitrogen oxides ($NO_x$), hydrocarbons (HC), $SO_2$, and particulate matter (PM) and $CO_2$ from ship during 2009 in Busan port was estimated based on activity-based method. The significant fraction (> 50%) of ship emission resulted from container and general cargo ships. Emission at port operation mode was the most dominant compared to at sea and maneuvering modes. Emission at North port was the largest source of air pollutants among ports. The magnitudes of air pollutants $NO_x$, $SO_2$, HC, $CO_2$, and PM in Busan port were $8.7{\times}10^3$, $8.23{\times}10^3$, $0.35{\times}10^3$, $4.86{\times}10^6$, and $0.67{\times}10^3$ ton/yr, respectively. The ratio of $NO_x$ to VOC is about 25. Our ship emission estimate is 2 times higher than that in CAPSS emission inventory.

• Journal of Korean Society for Atmospheric Environment
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• v.29 no.3
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• pp.307-316
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• 2013

The sensitivity of ozone to $NO_x$ and volatile organic compounds (VOCs) emission rates under different ventilation rates and $NO_2-to-NO_x$ emission ratios in a street canyon is investigated using a chemistry box model. The carbon bond mechanism IV (CBM-IV) with 36 gaseous species and 93 chemical reactions is incorporated. $NO_x$ and VOCs emission rates considered range from 0.01 to $0.30ppb\;s^{-1}$ with intervals of $0.01ppb\;s^{-1}$. Three different ventilation rates and three different $NO_2-to-NO_x$ emission ratios are considered. The simulation results show that the ozone concentration decreases with increasing $NO_x$ emission rate but increases with increasing VOCs emission rate. When the emission ratio of VOCs to $NO_x$ is smaller than about 4, the ozone concentration is lower in the street canyon than in the background. On average, the magnitude of the sensitivity of ozone to $NO_x$ emission rate is significantly larger than that to VOCs emission rate. As the $NO_x$ emission rate increases, the magnitude of the sensitivity of ozone to $NO_x$ and VOCs emission rates decreases. Because the ozone concentration is lower in the street canyon than in the background, the increased ventilation rate enhances ozone inflow from the background. Therefore, the increase in ventilation rate results in the increase in ozone concentration and the decrease in the magnitude of the sensitivity of ozone to $NO_x$ and VOCs emission rates when the emission ratio of VOCs to $NO_x$ is smaller than about 4. On the other hand, the increase in $NO_2-to-NO_x$ emission ratio results in the increase in ozone concentration because the chemical ozone production due to the $NO_2$ photolysis is enhanced. In the present experimental setup, the contribution of the change in $NO_2-to-NO_x$ emission ratio to the change in the sensitivity of ozone to $NO_x$ emission rate is larger than that of the change in ventilation rate.

• Asian Journal of Atmospheric Environment
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• v.12 no.1
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• pp.17-29
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• 2018

For the first time in the city of Riyadh, the formation of $O_3$ and its relationship with NO and $NO_2$ ($NO_x$) was investigated. Throughout the summer $O_3$, NO, and $NO_2$ were collected from three locations: residential, industrial, and rural areas. During the sampling period $O_3$ concentrations exceeded 1-hour local standards a few times yet remained consistent with the standards most of the time. The $O_3$ concentrations were observed highest in the rural location and lowest in the industrial area. The diurnal variation of NO followed a double peak: one in the morning and the other in the evening, representing the traffic pattern. Early morning NO peaks were observed in the rural location, which were attributed to the movement of NO from other locations. The $O_3$ concentrations depicted typical pattern, increasing after sunrise and reaching its maximum during midday. The highest $O_3$ concentrations were observed in the rural location followed by the residential and industrial. $NO_2$ photolysis rates were 3-4 times higher compared to other similar investigations, potentially due to intense solar radiation. A strong negative correlation was observed between $NO_x$ and $O_3$ values in the industrial location indicating photochemical activities around the industrial area were higher, likely due to additional $NO_x$ emissions from industries. Regression analysis of $NO_x$ and OX ($O_3+NO_2$) indicated that in residential and industrial locations at nighttime there were large $NO_x$ independent regional contributions which is attributed to VOCs. The Weekend Effect was observed in the city potentially due to the production of the OH radical and subsequent reactions with VOCs implying that the area is VOC-sensitive.

• Journal of the Korean earth science society
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• v.36 no.1
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• pp.36-50
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• 2015

The purpose of this study is to assign emission source profiles of volatile organic compounds (VOCs) and particulate matters (PMs) for chemical speciation, and to correct the temporal allocation factor and the chemical speciation of source profiles according to the source classification code within the sparse matrix operator kernel emission system (SMOKE) in the Seoul metropolitan area. The chemical speciation from the source profiles of VOCs such as gasoline, diesel vapor, coating, dry cleaning and LPG include 12 and 34 species for the carbon bond IV (CBIV) chemical mechanism and the statewide air pollution research center 99 (SAPRC99) chemical mechanism, respectively. Also, the chemical speciation of PM2.5 such as soil, road dust, gasoline and diesel vehicles, industrial source, municipal incinerator, coal fired, power plant, biomass burning and marine was allocated to 5 species of fine PM, organic carbon, elementary carbon, $NO_3{^-}$, and $SO_4{^2-}$. In addition, temporal profiles for point and line sources were obtained by using the stack telemetry system (TMS) and hourly traffic flows in the Seoul metropolitan area for 2007. In particular, the temporal allocation factor for the ozone modeling at point sources was estimated based on $NO_X$ emission inventories of the stack TMS data.

• Journal of Korean Society for Atmospheric Environment
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• v.32 no.2
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• pp.167-175
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• 2016

In this study, we estimate air pollutants emission from agricultural waste burning. We investigated activities related to agricultural waste burning such as crop burning rates, location, and time by region. The average crop burning rates per square meter farmland of fruits, pulses, barleys, cereals, vegetables, and special crops were $273.1g/m^2$, $105.7g/m^2$, $7.4g/m^2$, $121.0g/m^2$, $290.7g/m^2$, and $392.9g/m^2$, respectively. We estimated air pollutants emissions with pre-developed emission factors. The estimated air pollutant emission of agricultural biomass burning were CO 148,028 ton/year, $NO_x$ 5,220 ton/year, $SO_x$ 11 ton/year, VOC 59,767 ton/year, TSP 21,548 ton/year, $PM_{10}$ 8,909 ton/year, $PM_{2.5}$ 7,405 ton/year, and $NH_3$ 5 ton/year. When these results compared with the entire emissions of national inventory (CAPSS), CO, VOC, $PM_{10}$ account for about 17.8%, 6.2%, 6.7% of the total, respectively.

• Korean Journal of Materials Research
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• v.10 no.5
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• pp.328-334
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• 2000

The photocatalyst of $TiO_2$coated on glass bead was prepared from sol-gel method to remove the VOC (vola-tile organic compounds) by the photocatalytic reaction. The coated films were characterized by X-ray diffraction(XRD), specific surface area(BET), and scanning electron microscopy observation (SEM), The gas-phase photocatalytic degradation of trichloroethylene(TCE) and benzene with coated titanium dioxide on glass beads was in-vestigated using a fixed bed reactor. The degradation was calculated by the concentration difference with the retained on the reactor with aid of gas chromatography. At steady state, conversion yields were obtained for 80% of trichloroeth-vlene in 400 ppmv concentration and 65% on benzene in the range of concentration from 50 to 300 ppmv, respectively.

• Journal of Korean Society for Atmospheric Environment
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• v.34 no.1
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• pp.76-86
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• 2018

Using the CAPSS emissions data, we analysed changes and reasons in the annual air pollutant emission trends from 1999 to 2014. The CO emissions in the metropolitan area decreased steadily since 2001, when the latest model year of automobiles and high efficiency fuel were applied. However, other regions have not changed significantly in annual emissions. $NO_x$ emissions continued to increase since 2003, and unchanged after the decline in 2007. $SO_x$ emissions are steadily declining due to the supply of low sulfur oil. The $PM_{10}$ and $PM_{2.5}$ emissions were repeatedly affected by the influence of motor vehicles activities in the metropolitan area. In Gangwon and Chungcheong Provinces, emissions are increasing according to the use of coal in the manufacturing sector. And VOC and $NH_3$ emissions are increasing steadily every year. The major CO emission sources was automobiles in the metropolitan area. However, agricultural residue burning was the biggest CO sources in the Chungchong, Honam and Yeongnam Provinces. The major sources of $NO_x$ emissions differ from region to region. In the Metropolitan area, Honam and Yeongnam region, the truck was the largest emitter of $NO_x$. However, the cement kiln was the largest producer of $NO_x$ in Gangwon region, and the power plant is the largest emitter in Chungcheong Provinces.

• Journal of the Mineralogical Society of Korea
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• v.24 no.2
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• pp.101-110
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• 2011

Charcoal burning in the process of manufacture and ordinary use often release many constituent chemical species. As a result of open burning, the chemical composition as well as the physical properties of original material changes through the modification of surface properties of charcoal. Surface modification could be more responsible toward the outside elements for surface adsorption, it becomes easy to adsorb more toxic elements through surface adsorption. In this study, four kinds of commercially available charcoal were studied against the chemical and thermal stability along with the heavy metals and organic hazardous substances. Thermo gravimetric analysis (TGA) and differential scanning calorimetry, from room temperature to $400^{\circ}C$, were performed to study the weight loss and the changes in the behavior of those substances. According to TGA analysis, about 10% of weight loss was happened before $200^{\circ}C$. It was found that related weight loss of this temperature region may responsible to the gas phase organic matter. Natural charcoal, K1 and C1 show 15% of loss during the reaction heated to $400^{\circ}C$, while the artificial charcoal K2, C2 show the weight loss of about 20% was found. This is consistent with the main organic matter and VOC analysis results shown. Chemical composition based on the x-ray diffraction analysis was carried out. X-ray diffraction analysis reveals the existence of chemical additive in the forms of $Ba(NO_3)_2$, $BaCO_3$, and $NaNO_3$.

• Journal of Korean Society for Atmospheric Environment
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• v.30 no.3
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• pp.251-260
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• 2014

Biomass burning is one of the significant emission source of PM and CO, but a few studies are reported in Korea. Air pollutants emission from biomass burning such as wood stove and boiler, and wood-pellet stove and boiler were estimated in this study. Activity levels related to biomass burning such as fuel types, amount of fuel loading, and location and temporal variation were investigated by field survey over Korea. Fuel loadings were 14.9 kg/day for wood stove, 31.3 kg/day for wood boiler, 12.8 kg/day for wood-pellet stove, 32.5 kg/day for wood-pellet boiler during the season of active use. These were mostly burned in winter season from october to april of next year. Estimated annual emissions from wood stove & boiler were CO 76,677, $NO_x$ 710, $SO_x$ 70, VOC 20,941, TSP 6,605, PM10 2,921, PM2.5 1,851, and NH3 7 ton/yr, respectively. Emissions from wood-pellet stove and boiler were CO 32,798, $NO_x$ 1,830, $SO_x$ 25, VOCs 5,673, TSP 629, PM10 457, PM2.5 344, and $NH_3$ 2 ton/yr, respectively. When the emission estimates are compared with total emissions of the national emission inventory (CAPSS: Clean Air Policy Support System), Those occupy 12.5%, 2.8% of total national emission for CO and PM10, respectively. These results show wood and wood-pellet burning appliances were one of the major source of air pollution in Korea. In future, these types of heaters need to be regulated to reduce air pollution, especially in suburb area.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2002.10b
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• pp.423-424
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• 2002

Amount of regulated emissions (CO, $NO_x$, HC), and emissions of some groups of organic substances (volatile hydrocarbons, polyaromatics, and aldehydes) were measured in the standard ECE 83 test on spark ignition engine of a passenger car. The influence of the engine oil composition (mineral or fully synthetic) was examined. For both engine oils, exhaust emissions were measured with fresh oil as well as used oil at the end of the oil drain interval. Unleaded petrol and CNG were used as fuels in all experiments performed. The main conclusion made from the tests is that polyaromatics is the only part of th ε exhaust emissions that was influenced with the nature of the engine oil. Effect on the other components of emissions (aldehydes and VOC) was negligible. Emissions of polyaromatics were almost twice higher for fresh mineral as for fresh fully synthetic oil. The amount of polyaromatics in the exhaust emissions increased slightly with mileage for fully synthetic and substantially more for mineral engine oil.