• Journal of Korean Society of Environmental Engineers
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• v.35 no.5
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• pp.350-355
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• 2013

Little information is available for emission pathway even if HFC-134a that is known as one of the major greenhouse gases has been broadly used in Korea. This paper attempts to clarify the emission characteristics of HFC-134a used for refrigerant of cold drinking vending machines (CDVMs) at the use- and disposal-phase. We measured the residual amounts in the scrap CDVMs of 47 by applying commercial recover for refrigerant. The first-order kinetic model was introduced and the emission rate would be proportional to the remaining quantity of refrigerant. The emission factor at the use-phase was determined indirectly to be $6.9{\pm}0.7$ %/yr within a confidence interval of 95%, using information on residual amount and elapsed operation time at the disposal point. Correspondingly, the annual emission rate of HFC-134a per CDVM was determined to be 11.6 g. The average residual rate of HFC-134a in scrap CDVMs was assessed to be $62.5{\pm}2.2%$, leading to a potential emission amount of 144.8 g per scrap CDVM. The chemical compositions of refrigerants from scrap passenger vehicles are quite similar to those of new refrigerants, suggesting that the refrigerants from scrap passenger vehicles could be reused. During the recovering process of refrigerant, the recovered refrigerant was contaminated by compressor lubricant that accounted for about 30% in weight. It is necessary to separate the refrigerant from the recovered material contaminated by lubricant for recycling and reuse the refrigerant.

• 한국가스학회:학술대회논문집
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• 2003.05a
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• pp.83-90
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• 2003

• 한국가스학회:학술대회논문집
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• 2003.05a
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• pp.79-82
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• 2003

• Journal of Soil and Groundwater Environment
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• v.17 no.3
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• pp.21-31
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• 2012

This paper presents the short-term and long-term measures to determine the fugitive dust concentration in a contaminated site, which is a crucial step for the determination of particulate emission factor (PEF) for risk assessment. As a long-term measure, USEPA method employing Q/C value (inverse of the ratio of the geometric mean air concentration to the emission flux at center of a 0.5-acre square source) seems to be suitable as it reflects regional-specific meteorological conditions. However, it requires nation-wide database collection and interpretation. Use of ASTM method is an alternative as a short-term measure. The method is readily field-applicable as PEF calculation equation is simple and input parameters can be easily derived at the site of interest as well without the nation-wide efforts. Using ASTM method, PEF at the Former Janghang Smelter Site was determined. According to various mode of aggregate size distribution and fractions of vegetative cover, which are the most important factors in PEF calculation, PEF values at the Former Janghang Smelter Site varied greatly. When the mode of aggregate size distribution was set at 0.25 mm, PEF values at the Former Janghang Smelter Site was 5~20 times higher than the default PEF value (i.e., 35 ${\mu}g/m^3$) shown in the current Korean Soil Contamination Risk Assessment Guidance. On contrast, when the mode was set at 2 mm, PEF values at the Former Janghang Smelter Site was 160~640 times lower than the default PEF value in the Korean Guidance.

• Journal of Korean Society for Atmospheric Environment
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• v.23 no.5
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• pp.596-611
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• 2007

Resuspended dust from paved roads in Seoul and Incheon metropolitan areas is regarded as one of the major $PM_{10}$ sources in these areas, according to the recent emission estimates using the emission factors compiled in AP-42. It is well known that the AP-42 model for estimating $PM_{10}$ emissions from paved roads requires information on silt loadings of particular paved roads. The conventional AP-42 method (vacuum swept method) for road silt sampling, however, is expensive, time consuming, and dangerous. These drawbacks led us to develop a Mobile Dust Monitoring System (MDMS) capable of doing real time measurements of silt loading of paved roads, thereby we could get higher resolution silt loading data both in terms of time and space without too much human efforts and danger. In this study, for the real-time measurement of silt loading of paved roads, the principle used in the TRAKER method of U.S. Desert Research Institute was employed and the entire sampling systems including data acquisition system were designed for theses purpose and mounted on a SUV. The correlation between the silt loading measured by vacuum swept method and the speed corrected ${\Delta}Dust$ was derived for the vehicle-based silt loading measurements, and then the variations of silt loading on paved roads were surveyed using the MDMS in test routes of Seoul and Incheon. From the results of real-time measurements, temporal and spatial variations of silt loading data together with the existence of hot spots were observed for paved roads in Seoul and Incheon. The result of this study will be employed to estimate fugitive dust emissions from paved roads.

• Journal of Environmental Science International
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• v.30 no.10
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• pp.789-802
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• 2021

This study analyzed the characteristics of high PM_2.5 episodes that meets the concentration criteria of Emergency Reduction Measures Plan (ERMP) in Busan during the 2015-2020, and compared with those in Seoul. As a first step, the CAPSS-2017 emission data was employed to analyze the emission differences between Busan and Seoul, and pointed out that Busan emission included the dominance of ship emissions (37.7%) among total PM_2.5 city emissions, whereas fugitive PM_2.5 emission was the highest in Seoul. These emission characteristics are indicating that the controlling action plan should be uniquely applied to cope with ERMP in each region. We selected extremely high PM_2.5 episode days that meet the criteria of ERMP levels. In Busan, Ulsan, and Gyeongnam region, 15, 16, and 8 days of extremely high PM_2.5 cases were found, respectively, whereas Seoul showed approximately doubling of occurrences with 37 cases. However, the occurrences in summer season indicated big differences between two cities: the proportion of summer-season occurrence was 13-25% in Busan, whereas no single case have occurred in Seoul. This is suggesting the needs of comprehensive summer emission reduction plan with focusing on sulfur reduction to effectively cope with the ERMP levels in summer in the southeastern region, including Busan.

• Journal of Korean Society for Atmospheric Environment
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• v.29 no.5
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• pp.536-544
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• 2013

Even a small amount of hazardous air pollutants could have a harmful influence upon human beings, animals and plants. Hazardous air pollutants have the properties of toxicity, canceration and organism accumulation. They include heavy metals, volatile organic compounds, polycyclic aromatic hydrocarbons, dioxin, etc. The Clean Air Conservation Act has defined specific hazardous air pollutants and designated 35 pollutants, distinguishing them from common air pollutants for special control. This study investigates the history of the controls of specific hazardous air pollutants with reference to some relevant laws and regulations in Korea. It investigates the regulations at the permission stage, such as the restrictions on installation of emission facilities, the permission and reporting of installation of emission facilities, and the regulations at the operation stage, such as maintaining permissible emission levels, installation of measuring devices, dues for emission, self-measurement and securing environmental engineers. The current regulatory management is not so satisfactory in regards to the serious effects of specific hazardous air pollutants upon the human body. An advanced new concept, like the maximum available control technology in US, the facilities management standards, which will soon take effect, will be able to lessen the emissions of fugitive hazardous air pollutants. In addition, this study discusses some possible stricter controls on the emission facilities of specific hazardous air pollutants and proposes some measures to maintain and supplement the current systems.

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.121.2-121.2
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• 2016

PFA 라이닝 밸브 (PFA Lined Valve)는 고온 (~120oC) 고압 (~10 bar)에서 강한 부식성을 갖은 화학물질 (염산, 황산, 질산 등)을 이송시킬 수 있도록 내식성, 비점착성, 내열성 향상을 위한 불소계 수지 PFA (Perfluoroalkoxy)가 밸브 내면부에 가공되어 있으며, 고순도 화학약품 및 반도체 LCD 석유화학 제철 제약 분야 등의 제조공정에서 사용되고 있다. 미국 EPA (Environmental Protection Agency)에서는 석유화학 플랜트에서 발생되는 비산배출 (fugitive emission)의 대부분인 60% 정도가 밸브에서 발생된다고 보고하고 있으며, 근래 빈번한 불산 노출사고 내용을 매스컴에서 접할 수 있는 것처럼 PFA 라이닝 밸브가 설치되는 산업현장에서는 미소 누설에도 치명적인 인명피해 사고가 발생하기 때문에 국제규격에 따른 PFA 라이닝 밸브의 기밀누설에 관한 규제 및 관리가 중요하다. 본 논문에서는 가압진공법을 이용하여 PFA 라이닝 볼밸브의 비산배출 측정하였으며, 작동횟수/온도변화에 따른 PFA 라이닝 볼밸브의 비산배출 특성을 고찰하였다.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.05b
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• pp.312-313
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• 2003

환경부 훈령 제500호 "비산먼지 저감대책 추진에 관한 업무처리 규정(2001.9.4)"에 따르면 "비산먼지"라 함은 일정한 배출구 없이 대기 중에 직접 배출되는 먼지를 말하며, 대기환경보전법에서는 비산먼지 발생사업의 신고 및 발생억제 의무를 규정하고 있다. 미국 국가배출목록(U.S. EPA, 2000)에 의하면 미세먼지(PM10) 배출량의 89%를 비산먼지가 차지하고 있으며 이러한 수치는 비산먼지가 대기질에 미치는 영향도가 어느 정도인지를 예시하고 있다. 한편 우리나라의 경우 현재 미세먼지 배출목록에서 비산먼지 항목이 누락되어 있기 때문에 효율적인 대기질 관리를 위해서는 전국 지역별 비산 먼지 배출 목록의 구축이 시급한 것으로 사료된다. (중략)

• 한국가스학회:학술대회논문집
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• no.5
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• pp.189-194
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• 2002