• Wind and Structures
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• 제9권4호
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• pp.297-313
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• 2006

The concentration of air pollution along roads is higher than the surrounding area because ventilation efficiency has decreased due to the high-density use of space along roads in recent years. In this study, ventilation efficiency around a heavily traffic road covered by an elevated highway and hemmed in along its side by buildings is evaluated using Visitation Frequency (VF, the frequency for pollutant to return to the objective domain) and Purging Flow Rate (PFR, the air flow rate for defining the local domain-averaged concentration). These are analyzed using Computational Fluid Dynamics (CFD) based on the standard $k-{\varepsilon}$ model. The VF and PFR characteristics of four objective domains are analyzed in terms of the changes in wind direction and arrangements of the fencing dividing up and down direction in the road center under the elevated highway. The resulting VFs are more than 1.0 for all cases, which means that pollutants return to the objective domain restricted by the elevated highway and side buildings. The influence of the arrangement of the buildings around the objective domain and the structure in the domain on the VF is substantial. In cases where there are no obstacles under the elevated highway, the local air exchange rate in the domain tends to be improved. Using these indices, the urban ventilation efficiencies between different urban areas can be compared easily.

• Journal of the Korean Data and Information Science Society
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• 제27권3호
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• pp.577-586
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• 2016

최근 국내에서도 환경보건에 관한 관심이 급증하고 있는데, 특히 중금속은 발암의 특성이나 독성의 비임계성에서 대기오염물질과 구분이 되며, 낮은 수준일지라도 장기간 노출되면 호흡기계, 순환기계, 신경계 및 정신적 질환을 유발하는 것으로 알려져 있다. 이들 중금속 중 망간은 인체에 유해하지만 발암물질로 분류되지 않은 탓에, 망간 자체에 대한 연구는 미비한 편인고, 특히 망간은 자동측정장치 (AWS)를 통한 측정이 불가능하고 측정 및 분석에 고난도의 기술이 요구되어서 예산 등 비용효율성의 문제로 지속적인 관측이 불가능하다. 그러한 이유로 우리나라에서는 계절별로 10~12일 정도만 관측이 이루어지고 있다. 본 논문에서는 자동측정이 가능한 기온, 강수, 풍속 등 기상인자와 관측된 $SO_2$, $PM_{10}$, $O_3$ 등 대기질 물질을 이용한 망간 농도에 대한 통계 모형을 설계하고 이를 통해 부분적으로 관측된 망간 농도를 추정하여 망간의 위해성평가에 대한 정확도를 향상 시키고자 한다. 이를 위해 제안된 모형을 시화 반월 공업지역에서 관측된 자료를 적용하였다.

• 공업화학
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• 제8권3호
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• pp.517-523
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• 1997

본 연구는 유동층연소로에서 유,무연탄 혼합연소시 대기오염물질 발생과 연소효율에 관하여 실험하였으며, 실험결과는 다음과 같다. 유동층연소로 높이가 증가할수록 이산화황과 질소산화물의 농도는 증가하는 것으로 나타났으며, 무연탄 혼합비가 증가할수록 이산화황의 농도는 증가하였으나 질소산화물농도는 큰 변화가 없었다. 무연탄 혼합비가 증가할수록 비산유출율도 증가하였고 주입 가연성분에 대한 유출 가연성분비도 증가하였다. 또한, 무연탄 혼합비에 관계없이 비산유출입자의 평균입경에 따른 미연분 함량은 미세입자에서 대체로 높게 나타났다. 한편, 연소효율은 층온도 $850^{\circ}C$, 과잉공기 20% 이상에서 큰 차이를 보이지 않았으므로 유속 0.3m/s, 층온도 $850^{\circ}C$, 과잉공기비 20%의 조건으로 혼합연소시키는 것이 적절한 것으로 나타났다.

• Environmental Engineering Research
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• 제24권4호
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• pp.690-698
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• 2019

Air pollution has attracted ever-increasing attention because of its substantial influence on air quality and human health. To better understand the characteristics of long-range transported pollution, the single particle chemical composition and size were investigated by the single particle aerosol mass spectrometry in Fuzhou, China from 17th to 22nd January, 2016. The results showed that the haze was mainly caused by the transport of cold air mass under higher wind speed (10 m·s^-1) from the Yangtze River Delta region to Fuzhou. The number concentration elevated from 1,000 to 4,500 #·h^-1, and the composition of mobile source and secondary aerosol increased from 24.3% to 30.9% and from 16.0% to 22.5%, respectively. Then, the haze was eliminated by the clean air mass from the sea as indicated by a sharp decrease of particle number concentration from 4,500 to 1,000 #·h^-1. The composition of secondary aerosol and mobile sources decreased from 29.3% to 23.5% and from 30.9% to 23.1%, respectively. The particles with the size ranging from 0.5 to 1.5 ㎛ were mainly in the accumulation mode. The stationary source, mobile source, and secondary aerosol contributed to over 70% of the potential sources. These results will help to understand the physical and chemical characteristics of long- range transported pollutants.

• 한국조경학회지
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• 제13권1호
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• pp.1-24
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• 1985

The pinus trees planted by the road in the Seoul -Suwen high-way was surveyed on the damages due to air pollution during April and May in 1984. The results were as follows ; The concentration of SO$_2$was ranged from 0.003 to 0.05ppm, NOx from 0.03 to 0.1ppm and the amount of dust fall, from 10 to 110ton/km$^2$/month. While the concentrations of gaseous pollutants such as SO$_2$and NOx were notsignificantly different in the type of road and with in the distence of 20 meters from the road the dust falls were decreased as remoted from the road. The tissue damages of leaves were determined by the microscopic observation. The higher concentration of dust fall on the leaf, the more severe damage observed in the stomata. The attached dust of the leaves were ranged from 1l to 75mg/g of leaf, and those were significantly incereased as near from road. The sulfur contents of leaves were measured at 0.15g/100g of leaf in the 5 meters located and at 0.064g/100g of leaf in the 20 meters, and the lead contents, 45ug/g of leaf in the 5 meters and 24ug/g in the 15 meters. The appearent damages of plant were very much corelated to the attached dusts of leaves the sulfur contents and the amount of dust fall, and the multiple regression analysis between the damages and factors of air pollution were under taken. As increment of vehicle in future, the air Pollution was predicted and the plant damages were estimated.

• 한국대기환경학회지
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• 제28권2호
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• pp.172-181
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• 2012

Mercury is one of the most hazardous air pollutants. Recently, mercury has been a concern in domestic and overseas because it has lethal toxicity, long distance transport, persistence and bioaccumulation in the environment. Stationary combustion sources such as coal-fired power plants, waste incinerators, and cement kilns are the major sources of mercury emissions. The objectives of this study were to measure the concentration for mercury from coal-fired power plants and to calculate emission factor to estimate its emission. The results showed that the mercury concentrations in the flue gas were 1.63-3.03 mg/$Sm^3$ in anthracite-fired power plants (average 2.32 mg/$Sm^3$) and 1.95-3.33 mg/$Sm^3$ in bituminous-fired power plants (average 2.6 mg/$Sm^3$). Mercury emission factor was estimated as 25.74 mg/ton for anthracite-fired power plants and 12.48 mg/ton for bituminous-fired power plants. Because actual measurements are limited in quantity, it is desirable to refine our estimates by extending the actual measurements.

• 한국환경보건학회지
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• 제49권1호
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• pp.30-36
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• 2023

Background: Among various pollutants, fine particle (PM_2.5, defined as particle less than 2.5 nm in aerodynamic diameter) shows the most consistent association with adverse health effects. There is scientific evidence documenting a variety of adverse health outcomes due to exposure to PM_2.5. Objectives: This study aims to assess the health benefits of that would be achieved by meeting the World Health Organization's air quality guidelines for PM_2.5 using AirQ+ and BenMAP. Methods: We estimated PM_2.5 related health benefits in Korea from implementing the World Health Organization's air quality guidelines (annual average 5 ㎍/m³ and 10 ㎍/m³) and Korea's National Ambient Air Quality Standard (annual average 15 ㎍/m³). We used World Health Organization's AirQ+ and U.S. Environmental Protection Agency's Environmental Benefits Mapping and Analysis Program. Results: The annual number of avoided PM_2.5 related premature deaths exceeding WHO guideline levels was assessed using both AirQ+ and BenMAP. We estimated that the health benefits of attaining the World Health Organization's air quality guidelines for PM_2.5 (annual average 5 ㎍/m³) would suggest an annual reduction of 26,128 (95% confidence interval [CI]: 17,363~34,024) and 26,853 (95% CI: 18,527~34,944) premature deaths. Conclusions: Our study provided useful information to policy makers and confirms that the reduction of PM_2.5 concentration would result in significant health benefits in Korea.

• 한국대기환경학회지
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• 제34권2호
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• pp.233-243
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• 2018

This study was carried out to characterize the ambient levels of PAH concentrations in Pohang city, where steel industry has been intensively developed. A large amount of PAH emissions from steel production and related industries in Pohang are concerned about the environmental health hazards of nearby residents. TSP samples were seasonally collected during 10 days at four sites in Pohang from April to December 2010. Each sample was collected for 24 hours using high-volume air sampler. All samples were extracted by $soxtec^{TM}$ before concentration of 1.0 mL. The concentrates were analyzed by GC/MS. The prevailing wind direction was southwest and west-southwest in Pohang during the measurement period. Variations of TSP concentrations appeared to be similar between four sites. The highest TSP concentration was found in fall, while the lowest in summer. The highest PAH concentration was found at an industrial site, while the lowest at a residential/commercial site. In the case of BaP, the average concentration at the industrial site was $0.63{\pm}0.66ng/m^3$, which was approximately 2 times of the residential/commercial site. The paired t-test (p<0.05) showed significant differences between industrial and residential area. Particulate PAH concentrations were higher in the winter and lower in the summer. The concentrations of BaP in winter were 2~10 times higher than those in the other three seasons. This study clearly demonstrated the impact of steel industry on the elevated levels of PAH in Pohang city.

• 한국환경보건학회지
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• 제32권5호
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• pp.522-531
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• 2006

This study has been conducted to evaluate the influence of ambient heavy metals to the air quality and to find their sources in Ulsan. Korea. The distribution characteristics of ambient heavy metals with wind direction were investigated by using pollution-rose diagram. Carcinogenic risk for five trace heavy metals (Pb. Cd, Cr, Mn, and Ni), which are classified to carcinogenic material by US EPA, are assessed according to the classification system of USEPA and WHO. According to pollution-rose calculation on pollutants sources, Pb and Cu in Deoksin, which is an adjacent to Onsan industrial complexes, were $0.1058\;and\;0.3242{\mu}g/m^3$. These concentration levels are the highest at all sampling sites. From this result we could confirm that it was affected by Onsan industrial complex that is located northeast of Deoksin.,And the maximum concentration of Cd, Cr, and Ni were $0.0306,\;0.0102,\;and\;0.0146\;{\mu}g/m^{3} in Yeocheon respectively. Because Yeocheon is in the Mipo industrial complexes, which have many combustors, incinerators, and manufacturing facilities compared to other regions. In carcinogenic risk assessment, Pb, Ni, and Mn concentration level at six sampling sites were lower than the risk level guideline values ($10^{-5}$) of WHO. However, $Cr^{6+}$ and Cd concentration in Yeocheon were 60% and 205% higher than the guideline values of WHO. Therefore it is very important that the emission from industrial complexes were carefully managed and controlled to improve air quality in residential area.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
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• pp.1309-1314
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• 2011

People spend approximately 80 ~ 90 % of their time in various kinds of indoor spaces. And, in metropolitan area, most people spend more than 1 hour in public transportation everyday. For this reason, people's interest in the indoor air quality is drastically increasing. Among various indoor air pollutants, $CO_2$ is one of the most severe environmental concerns. Ventilation is commonly used to keep low $CO_2$ concentration in the passenger cabin. However, ventilation may worse the indoor air quality problem in case of subway because the tunnel is seriously polluted by particulate matters. In this study, an alternative way to remove $CO_2$ was suggested. The adsorption of $CO_2$ by $CO_2$ adsorbent was studied. Zeolite modified with base was prepared, and $CO_2$ removal performance was tested in $4m^3$ and $24m^3$ environmental chambers. It was found that $CO_2$ adsorbent could effectively remove $CO_2$ in the chambers.