• Title/Summary/Keyword: Pollutants

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A Study on the Treatment of Nondegradable Pollutants by Ultrasonic Irradiation (초음파에 의한 난분해성물질 처리에 관한 연구)

  • 손종열;모세영;문경환
    • Journal of Environmental Health Sciences
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    • v.21 no.3
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    • pp.102-106
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    • 1995
  • This study was performed to examine factors affecting the decompostion of nondegradable polluants(trichloroethylene(TCE), phenol) using ultrasonic irradiation. The TCE and phenol, which are major hazard compounds causing environmental pollution, were not decomposable pollutants by conventional treatment. The results show that the oxidation and reduction reaction of ultrasound produced $H_2O_2$, $H^+$ and $OH^-$ radical, which decomposed pollutants of TCE and phenol in water. It was confirmed that the ultrasonic irradiation showed an excellent removal efficiency for the nondegradable pollutants than any other processes, utilized in the treatment of organic compounds in the industrial wastewater. Conclusively, these results suggest that ultrasonic irradiation may be highly useful for the treatment of wastewaters contaminated organic pollutants, which is difficult to treat economically by conventional process.

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The Domestic Research Trend and the Road Map of Health Risk Assessment of the Air Quality in Korea (대기환경부문 건강위해평가의 국내 연구 동향과 발전방향)

  • Shin, Dong Chun
    • Journal of Korean Society for Atmospheric Environment
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    • v.29 no.5
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    • pp.528-535
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    • 2013
  • Air pollution in large cities is reduced through the environmental health policies, but due to increased population and automobile, some pollutants are still a problem. These air pollutants are known to cause asthma and respiratory diseases. According to an OECD report, the number of premature deaths will increase. Hazardous air pollutants should be managed through a systematic monitoring, risk assessment, and many studies are in progress. In order to manage hazardous air pollutants, transformation of policy for the protection of human health is required. management policy through the calculation of the excess number of deaths that occur from hazardous air pollutants for the public health is necessary. Korea has put a lot of efforts for air quality, but health risk assessment should be more considered.

Numerical Simulation for Diffusion and Movement of Air Pollutants in Atmospheric Flow Coastal Urban Region (연안도시지역의 대기유동장에서 대기오염물질의 확산과 이동에 관한 수치모의)

  • 이화운;김유근
    • Journal of Environmental Science International
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    • v.6 no.5
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    • pp.437-449
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    • 1997
  • To predict diffusion and movement of k pollutants In coastal urban region a numerical simulation shouts be consider atmospheric flow field with land-sea breeze, mountain-valley wand and urban effects. In this study we used Lagrangian [article dispersion method In the atmospheric flow field of Pusan coastal region to depict diffusion and movement of the Pollutants emoted from particular sources and employed two grid system, one for large scale calculating region with the coarse mesh grid (CMG) and the other for the small region with the One mesh 914 (FMG). It was found that the dispersion pattern of the pollutants followed local circulation system in coastal urban area and wale air pollutants exhausted from Sasang moved Into Baekyang and Jang moutain, air pollutants from Janglim moved into Hwameong-dong region.

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A Numerical Study for the Design of Ventilation System for the gaseous Pollutants (기체 유해물질 환기장치 설계를 위한 수치모사)

  • 엄태인
    • Journal of the Korean Society of Safety
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    • v.9 no.4
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    • pp.77-84
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    • 1994
  • A study is performed in order to design a effective ventilation equipment for the pollutants in workshop. The procedure has been used to calculate the flow in a confined rectangular space channel. A cross free stream is flowed from open space and jet stream including pollutants is injected from bottom area. Calculation results shows a wake region which exists immediarely downstream of the jet discharge and are compared with the experimental data. Calculation data are in good agreement with experimental results. A wake plays an important role on a stagnation of the pollutants. Thus ventilation equipment has to be designed without a stagnation region which give rise to concentration stratification. In this study, calculation parameters are the position and velocity of pollutants and fresh air from cross free stream. It is concluded that more measurements of local velocities, temperatures and concentrations of the pollutants.

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The Role of Fronts on the Vertical Transport of Atmospheric Pollutants II: Vertical transport experiment using MM5 (대기오염물질의 연직 수송에 미치는 전선의 역할 II: MM5를 이용한 3차원 연직 수송 실험)

  • Nam, Jae-Cheol;Hwang, Seung-On;Park, Soon-Ung
    • Atmosphere
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    • v.14 no.4
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    • pp.3-18
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    • 2004
  • Neglecting the vertical transport from the surface, most of the previous studies on the long-range transport of pollutants have only considered the horizontal transport caused by the free atmosphere wind. I used a three dimensional numerical model, MM5 (The fifth generation Penn State Univ./NCAR Mesoscale Model) for the simulation of vertical transport of pollutants and investigated the mechanism of the vertical transport of atmospheric pollutants between planetary boundary layer(PBL) and free atmosphere by fronts. From the three dimensional simulation of MM5, the amount of pollutants transport from PBL to free atmosphere is 48% within 18 hour after the development of front, 55% within 24 hour, and 53% within 30 hour. The ratios of the vertically transported pollutant for different seasons are 62%, 60%, 54%, and 43% for spring, summer, fall, and winter, respectively. The most active areas for the vertical transport are the center of low pressure and the warm sector located east side of cold front, in which the strong upward motion slanted northward occurs. The horizontal advection of pollutants at the upper level is stronger than at the lower level simply because of the stronger wind speed. The simulation results shows the well known plum shape distribution of pollutants. The high concentration area is located in the center and north of the low pressure system, while the second highest concentration area is in the warm sector. It is shown that the most important mechanism for the vertical transport is vertical advection, while the vertical diffusion process plays an important role in the redistribution of pollutants in the PBL.

Evaluation of Green House Gases (GHGs) Reduction Plan in Combination with Air Pollutants Reduction in Busan Metropolitan City in Korea

  • Cheong, Jang-Pyo;Kim, Chul-Han;Chang, Jae-Soo
    • Asian Journal of Atmospheric Environment
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    • v.5 no.4
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    • pp.228-236
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    • 2011
  • Since most Green House Gases (GHGs) and air pollutants are generated from the same sources, it will be cost-effective to develop a GHGs reduction plan in combination with simultaneous removal of air pollutants. However, effects on air pollutants reduction according to implementing any GHG abatement plans have been rarely studied. Reflecting simultaneous removal of air pollutants along with the GHGs emission reduction, this study investigated relative cost effectiveness among GHGs reduction action plans in Busan Metropolitan City. We employed the Data Envelopment Analysis (DEA), a methodology that evaluates relative efficiency of decision-making units (DMUs) producing multiple outputs with multiple inputs, for the investigation. Assigning each GHGs reduction action plan to a DMU, implementation cost of each GHGs reduction action plan to an input, and reduction potential of GHGs and air pollutants by each GHGs reduction action plan to an output, we calculated efficiency scores for each GHGs reduction action plan. When the simultaneous removal of air pollutants with the GHGs reduction were considered, green house supply-insulation improvement and intelligent transportation system (ITS) projects had high efficiency scores for cost-positive action plans. For cost-negative action plans, green start network formation and running, and daily car use control program had high efficiency scores. When only the GHGs reduction was considered, project priority orders based on efficiency scores were somewhat different from those when both the removal of air pollutants and GHGs reduction were considered at the same time. The expected action plan priority difference is attributed to great difference of air pollutants reduction potential according to types of energy sources to be reduced.

Emission Reduction of Air Pollutants Produced from Chemical Plants

  • Lee, Byeong-Kyu;Cho, Sung-Woong
    • Journal of Korean Society for Atmospheric Environment
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    • v.15 no.E
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    • pp.29-38
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    • 1999
  • This study identified emission sources and emissions of air pollutants such as volatile organic compounds (VOCs), solvents, and acid gases produced from chemical plants. We collected air samples from various processes, reactors and facilities using VOC detectors and workers' experience. We identified chemical structures and emission concentrations of air pollutants. We analyzed total emissions of air pollutants emitted from the chemical plants. Also, we developed some emission reduction technologies based on chemical types and emission situations of the identified air pollutants. For reduction of air emissions of acid gases, we employed a method improving solubility of pollutants by reducing scrubber operation temperature, increasing surface area for effective contact of gas and liquid, and modifying or changing chemicals used in the acid scrubbers. In order to reduce air emissions of both amines and acid gases, which have had different emission sources each other but treated by one scrubber, we first could separate gas components. And then different control techniques based on components of pollutants were applied to the emission sources. That is, we first applied condensation and then acid scrubbing method using H2SO4 solution for amine treatment. However, we only used an acid scrubbing method using H2O and NaOH solution for acid gas treatment. In order to reduce air emissions of solvents such as dimethylformamide and toluene, we applied condensation and activated carbon adsorption. In order to reduce air emissions of mixture gases containing acid gases and slovents, which could not be separated in the processes, we employed a combination of various air pollution control devices. That is, the mixture gases were passed into the first condenser, the acid scrubber, the second condenser, and the activated carbon adsorption tower in sequence. In addition, for improvement of condensation efficiency of VOCs, we changed the type of the condensers attached in the reactors as a control device modification. Finally, we could successfully reduce air emissions of pollutants produced from various chenmical processes or facilities by use of proper control methods according to the types and specific emission situations of pollutants.

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Concentration of Air Pollutants and Asthma in Taejon City (대전지역 대기오염물질농도와 천식 환자수의 관련성)

  • 서원호;장성실;권호자
    • Journal of Environmental Health Sciences
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    • v.26 no.2
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    • pp.80-90
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    • 2000
  • To determine the effect of air pollutants in Taejon City, we used medical insurance claim data for asthma and the data monitored from telemetry system of Ministry of Environment for air pollutants and meteorological factors. From November 1st, 1997 to October 31th, 1998, 95,629 asthma patients were covered by medical insurance at Taejon City. Subjects were composed of 49,563 males (51.8%) and 46.336 females(48.2%), and among the subjects, the proportion under 15 years old was 62.8% of the total. During the study period, daily mean concentrations of each air pollutants-So2, No2, CO, O3 and TSP-were 9.8 ppb, 17.6 ppm, 1.414 pp, 17.3 ppb and 60.6 $\mu\textrm{g}$/㎥, respectively, which were lower than each of the environmental recommended exposure levels, Through the simple correlation analysis between each air pollutants and meteorological factors, O3 was positively correlated with temperature, but negatively with relative humidity. TSP, SO2, NO2, CO were negatively correlated with meteorological factors, and these air pollutants except O3 were positively correlated with each other, O3 was correlated with TSP positively but the others negatively. Estimating relative risks of each air pollutant with the baseline general additive model, daily mean concentrations of TSP(Lag 0, 1, 4, 5day) were significantly associated with the increase of the asthma admission. Two age subgroups, under 15 and 15~54 have shown various association of all air pollutants concentration with the asthma admission. However, in case of over 54 age subgroup, only TSP(Lag 0 day) among all air pollutants was associated with the asthma admission. Each of ambient outdoor pollutant concentrations in Taejon City are significantly associated with the admission of asthma patients even though all concentrations in Taejon City are significantly associated with the admission of asthma patients even though all concentrations were much lower than the environmental recommended exposure levels. Therefore, continuous effort lowering air pollutant concentration and introducing an active environmental conservation policy should be implanted for preventing hazardous health effects. Considering major proportion of asthma admissions, high susceptibility and less confounding factors among the age subgroup under 15 will be a useful target population for assessing such health effect monitoring.

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A Review on the Characteristics of Air Pollutants Emitted from Passenger Cars in Korea

  • Jung, Sungwoon;Kim, Jeongsoo
    • Journal of ILASS-Korea
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    • v.21 no.4
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    • pp.223-236
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    • 2016
  • On-road source emissions are major air pollutants and have been associated with serious health effects in Seoul metropolis. Thus, it is of fundamental importance to have an accurate assessment of vehicle emissions in order to implement an effective air quality management policy. As a result, there is a need to overview vehicle emission characteristics of air pollutants. This article discusses vehicle exhaust sampling and chemical analysis, emission characteristics of air pollutants, and emission regulations from passenger cars. The vehicle exhaust sampling and chemical analysis methods were described in particulate matter and gaseous compounds. In this article, chassis dynamometer, measurement instrumentation for nano-particulate matter and carbon compounds analysis device were described. For the gasoline and diesel vehicles, the effective parameters of emissions were average vehicle speed, vehicle mileage and model year. The particle number emissions for diesel nano-particles were sensitive to the sampling conditions. Also, the particle number emissions with a diesel particle filter (DPF) largely reduced rather than those without it. This article also describes different emission characteristics of air pollutants according to biodiesel or bioethanol mixing ratio. The Korean emission standards for passenger cars were compared with those of the US and EU. Finally, the objective is to give an overview of relevant background information on emission characteristics of air pollutants from passenger cars in Korea.

Study on Accelerated Aging Characteristics of Paper-Records by Air Pollutants (종이 기록물의 대기 중 유해물질에 의한 가속 열화 특성 연구)

  • Park, Mi-Seon;Jeong, So-Yoon;Hwang, Ji-Hyun;Kim, Hyoung-Jin;Kim, Shin-Do
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.46 no.4
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    • pp.76-84
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    • 2014
  • Preventive conservation is one of most important issues in the field of conservation for paper-records. Many researchers have been studied environmental factors such as effects of humidity, temperature, biological attack and air pollutants. Air pollutants strongly associated with oxidative and hydrolytic degradation of cellulose. It is important to control air pollutants in storage environment to improve stabilities of conservation environment. Four paper samples have been analyzed for their accelerated aging characteristics by air pollutants, sulfur dioxide, nitrogen dioxide, ozone, carbon monoxide. Physical and optical properties and weight molar masses(Mw) showed that interactions between air pollutants and paper sample. Nitrogen dioxide, ozone caused severe damage to cellulose in paper by hydrolytic and oxidative decompositions during aging.