• Title/Summary/Keyword: Concentration of pollutants

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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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A Study of Comparison of outflow characteristics of pollutants by rainfall event of forest area near Juam lake basin (주암호 유역의 강우사상에 따른 오염물질의 유출특성)

  • Kim, Nam-Joung;Shin, Dae-Yewn
    • Journal of environmental and Sanitary engineering
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    • v.22 no.4
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    • pp.87-104
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    • 2007
  • The objective of this study is to estimate the load of pollutants caused from the forest area among non-point pollutants within the Juam lake. The surveyed forest area was classified into broad-leaved, conifer, mixed and herbage area by forest tree type. Water quality and flux were investigated under rainfall and non-rainfall, respectively. Then, pollutant loading was evaluated by using the values of unit pollutant loading factor of each point and area of forest zone. Water quality analysis results of runoff by forest tree types were as follows. - Annual BOD, $COD_{Mn}\;and\;COD_{Cr}$ concentration of runoff in conifer area was high, and particle and biological recalcitrant compounds were flowed highly. - SS, T-N and T-P concentration was high in runoff from broad-leaved area, and biological degradable compounds was flowed. - Water quality of water from valley was maintained good under non-rainfall and could be utilized as fresh drinking water. Through water quality standard investigation, a countermeasure establishment was necessary to secure a good quality of drinking water - BOD, $COD_{Mn},\;and\;COD_{Cr}$ concentration of Bo-sung river was higher 1.5 times than other 2 streams, and because of high T-N, and T-P concentration in Songgwang stream, the management for this was necessary.

Determination of Persistent Organochlorine Pollutants in Rat Hair by Gas Chromatography-Mass Spectrometry

  • Shin, Ho-Sang;Pyo, Hee-Soo;Park, Song-Ja
    • Bulletin of the Korean Chemical Society
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    • v.25 no.10
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    • pp.1489-1494
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    • 2004
  • A gas chromatography/mass spectrometric assay method was developed for the determination of persistent organochlorine pollutants (POPs) in hair. For the exact extraction study was used hair of rat exposed with POPs. Sonication of the hair matrix with 3 M HCl solution in methylene chloride of the extraction methods studied was the most efficient and rapid sample preparation method. After sonication of rat hair was achieved clean up with a solid phase extraction procedure using silica gel-florisil. Elution was performed with 8 mL of methylene chloride. The eluate was concentrated to approximately 100 ${\mu}L$ and analyzed by gas chromatography-mass spectrometry (GC-MS). Detection limits of POPs were in the concentration range of 0.6-1.2 ng/g in rat hair. Aldrin, dieldrin, p,p-DDT and mirex were dosed rat for 4 weeks at concentration of 0.01 mg/L in drinking water and detected in rat hair at concentration of 2.8, 11.3, 7.9 and 15.6 ng/g, respectively. Aldrin and p,p-DDT were metabolized to dieldrin and p,p-DDE, which were detected in concentration of 9.7 and 2.9 ng/g in rat hair, respectively. The developed method may be valuable to be used to analyze POPs in human hair.

Mathematical Modelling of Biofilter for Waste Air Biotreatment (폐가스 처리에 대한 바이오필터의 수학적 모델링)

  • Im, Gwang-Hui
    • KSBB Journal
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    • v.14 no.5
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    • pp.550-560
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    • 1999
  • There have been many research efforts on biofilter modeling including Ottengraf et al. who derived a model equation for the concentration profile of pollutants(e.g., VOCs) in the biolayer and solved their outlet concentration of the waste gas stream through biofilter. However, for most of research works done so far, the effects to explain the effect of adsorption of organic particles to medium(i.e., adsorbent) have been ignored. In this work biofilter modeling accompanying process lumping has been proposed and the theoretical effect of adsorption property of the medium, on the biofilter performance of eliminating organic components in waste gas stream, is intensively discussed.

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Numerical Simulation of $NO_2$Concentration considering SST Effects (SST 효과를 고려한 계절별 $NO_2$농도 수치모의)

  • 원경미;이화운;김유근
    • Journal of Environmental Science International
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    • v.10 no.3
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    • pp.187-194
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    • 2001
  • For the purpose of predicting air pollutants concentration in Pusan coastal urban, we used an Eulerian model of flow and dispersion/chemistry/deposition process considering SST effects which estimate through POM. The results of air quality model including emission from various sources show that the seasonal variation pattern of respective pollutants was affected by the seasonal SST fields and local circulation. Horizontal deviation of diurnal SST was 2.5~4K, especially large gradients in coastal region. Through numerical simulation of wind fields we predicted that local circulation prevailed during daytime in summer and nighttime in winter. So high concentration distribution showed toward inland in spring and summer seasons, while high concentration distribution showed at inland near coast in autumn and winter.

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Yearly Variation and Influencing Factors of Ozone Concentration in the Ambient Air of Seoul (서울시 대기중 오존오염도의 연도별 변화와 그 영향인자 분석: 광화문 지역을 중심으로)

  • Lee, Ki-Won;Kwon, Sook-Pyo;Chung, Yong
    • Journal of Korean Society for Atmospheric Environment
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    • v.9 no.1
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    • pp.107-115
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    • 1993
  • This study was carried out to find the characteristics of surface ozone concentration data obtained during 1988-1991 by the Korea Ministry of Environment. Seasonal data (spring, summer, autumn and winter) wre obtained in May, August, November and February respectively at Kwanghwamun in Seoul. The pollutants analyzed in this study are $SO_2, TSP, CO, NO, NO_2 and NO_2/NO$. Atmospheric factors such as solar radiation, wind speed, relative humidity, cloud amount and atmospheric temperature are also analyzed. The influence of pollutants and atmospheric factors that affect ozone concentration were analyzed by statistical method. The results are summarized as follows : 1. The ozone concentration varied seasonally. The maximum values were 23 ppb in spring, 33 ppb in summer, 16 ppb in autumn and 13 ppb in winter. So the seasonal ozone value was highest in Summer. 2. Te diurnal concentration of ozone was highest during 2-4 P. M. and was very low in the morning and evening. 3. The maximal correlation coefficients of each season between ozone concentration and the influencing pollutants or atmospheric factors asr as follows ; a. spring, r = 0.44(solar radiation) b. summer, r = -0.59(relative humidity) c. autumn, r = -0.55(relative humidity) d. winter, r = -0.58($NO_2$) 4. The major factor affecting the ozone concentration in spring was solar radiation, Relative humidity was the first affecting factor in summer, autumn and $NO_2$ concentration was dominant in winter.

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The Effect of Ventilation and Concentration of Indoor Air Quality at Indoor Parking Lots (실내주차장의 실내공기질 농도특성 및 환기에 의한 저감효과)

  • Park, Jeong-Ho
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.20 no.4
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    • pp.241-247
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    • 2010
  • Recently, indoor air quality (IAQ) has been one of the major concerns of people. Indoor parking lots are subject to be exposed to high concentrations of air pollutants emitted from vehicles. This study was performed to investigate indoor air quality (IAQ) at indoor parking lots. Sampling sites were selected 5 indoor parking lots. Target indoor air quality parameters include a number of criteria pollutants such PM$_{10}$, CO, CO$_2$, and HCHO. In addition, a variation of IAQ according to ventilation system operating was measured at C site (underground parking lot). In general, all pollutants were maintained below indoor air quality maintenance standards. The indoor air quality at indoor parking lots was affected by the availability of the ventilation facility and their operation frequency. At the underground parking lot (C site) with ventilation system, TVOC concentration according to ventilation system operating were found to be lower operating (488.2 ${\mu}g/m^3$) than non-operating (1,401.2 ${\mu}g/m^3$).

Effects of Emission from Seoul Metropolitan Area on Air Quality of Surrounding Area Using MESOPUFF II Model (MESOPUFF II모델을 이용한 서울시 $SO_2$배출량이 주변지역 대기질에 미치는 영향 분석)

  • 조창래;이종범
    • Journal of Korean Society for Atmospheric Environment
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    • v.14 no.6
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    • pp.563-576
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    • 1998
  • To study the influences of the emission sources during lune 13∼15 1997 in Seoul, MESOPVFF II model has been used. The MESOPVFF II model includes terrain effects, chemical transformation and removal processes. Data of 20 surface meteorological stations and the upper air station on mid-west area in Korea were used as a DWM (Diagnostic Wind Model) input data. This model is likely to be applicable because the predicted SO2 concentration was well matched with measured 502 concentration in Seoul and Kyonggido. In generally air pollutants in Seoul have major influence on the other cities but the result of modeling appeared also air pollutants of the other cities influence on Seoul. Finally, in the case of calculating the air quality by diffusion model, the influences of air pollutants emitted in metropolitan area as well as the emission rate in modeling area should be considered.

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제철소 폐수의 재활용을 위한 막분리 공정

  • Jeon, In-Su;Lee, Cheol
    • Proceedings of the Membrane Society of Korea Conference
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    • 1995.06a
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    • pp.51-71
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    • 1995
  • In case of industrial wastewater, it has various pollutants, high concentration and different physical, chemical properties each other in accordance with classofocation of wastewater. Therefore, after inquiring into the influence on the membrane of the dissolved pollutants, we should select the membrane of best efficient quality.

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Runoff Characteristics of Nonpoint Pollutants Source in Urban Area (중소도시지역 비점오염물질의 유출 특성)

  • Lee, Geon-Jik;Seong, Jin-Uk;Park, Ju-Hyun;Joe, Gyu-Soo;Park, Je-Chul
    • Journal of Environmental Science International
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    • v.19 no.7
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    • pp.819-827
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    • 2010
  • This study was conducted to investigate runoff characteristics of non-point pollutants source at the urban area in boeun area, Chungbuk Province. The monitoring site covering the watershed of $2.11\;km^2$ contains about 40.3 % of total watershed with the urban area. The monitoring was conducted with six events for five months and Event Mean Concentration(EMC) and Site Mean Concentration(SMC) of SS, BOD, CODMn, T-N, T-P were calculated on the result of the water quality parameters. As a result of the comparion between Arithmetic Mean Concentration and Event Mean Concentration, it showed that over all Event Mean Concentration was higher than Arithmetic Mean Concentration. And it showed that SS, BOD, T-P featured the first-flushing effect, showing relatively high concentration in early-stage storm event.