• Title/Summary/Keyword: Secondary air pollution

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Characteristics of long-range transported PM2.5 at a coastal city using the single particle aerosol mass spectrometry

  • Cai, Qiuliang;Tong, Lei;Zhang, Jingjing;Zheng, Jie;He, Mengmeng;Lin, Jiamei;Chen, Xiaoqiu;Xiao, Hang
    • Environmental Engineering Research
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    • v.24 no.4
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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.

The Status and Direction of State Implementation Plans to Improve Air Quality of the United States (미국 주 정부 실천계획의 현황 및 추진방향)

  • 신태주
    • Proceedings of the Korea Air Pollution Research Association Conference
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    • 2000.04a
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    • pp.49-51
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    • 2000
  • 오존은 온도가 높고 태양 빛이 강한 여름철에 휘발성 유기화합물(Volatile Organic Compounds)과 질소화합물(NOx)의 광 화학 반응으로 생성되는 이차적 공해물질(Secondary Air Pollutant)이다. 성층권에 존재하는 오존은 피부암을 유발시키는 강한 자외선을 차단하고 흡수하는 고마운 존재이지만, 급속한 산업발달로 다량의 공해물질유출로 인해 생성된 지표면상의 오존은 대단히 유독해서 높은 농도에서 장시간 호흡 시 호흡기관의 장애는 물론이고 치사까지 이르게 하는 것으로 알려져 있다. (중략)

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Biotreatment Technologies for Air Pollution Control (생물학적 처리기술을 이용한 대기오염 제어)

  • Won, Yang-Soo
    • Clean Technology
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    • v.13 no.1 s.36
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    • pp.1-15
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    • 2007
  • Biological treatment is a relatively recent air pollution control technology in which off-gases containing biodegradable odors and volatile organic compounds(VOCs) are vented through microbes. It is a promising alternative to conventional air pollution control methods. Bioreactors for air pollution control have found most of their success in the treatment of dilute and high flow waste air streams containing VOCs and odor compounds. They offer several advantages over traditional technologies such as incineration or adsorption. These include lower treatment costs, absence of formation of secondary pollutants, no spent chemicals, low energy demand and low temperature treatment. The three most widely used technologies are described, namely biofiltration, biotrickling filtration, bioscrubbing. The most widely used bioreactor for air pollution control is biofilter, but it has several limitations. In the past years major progress has been accomplished in the development of vapor phase bioreaction systems, for solving problems of biofilter. Biotrickling filters are more complex than biofilters, but are usually more effective, especially for the treatment of compounds which are difficult to degrade or compounds that generate acidic by-products. This, paper reviews fundamental and theoretical/practical aspect of air pollution control in biofilter, biotrickling filter and bioscrubber, focusing more extensively on biotrickling filtration. Special emphasis is given to the operating parameters and the factors influencing performance for air pollution control, and cost estimation in biotreatment technologies.

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The Study on Chemical Conversion of Acidic Gases in Air (대기중 산성가스의 화학적 변화에 관한 연구)

  • Park Tae-Sool
    • Journal of environmental and Sanitary engineering
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    • v.20 no.4 s.58
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    • pp.1-8
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    • 2005
  • Pocheon is a basin geographically, and the diffusion of air pollutants is very difficult. Thus, it is essential to consider the characteristics of geographical and weather conditions before industrial complex and various air pollution sources are developed in the area. It is recommended that Environmental Impact Statements (EIS) must be carried out before any action is taken. Constantly occurring fog in the Pocheon area absorbs large amounts of acidic gases, and it transformed into the secondary pollutants such as the salts of sulfate and nitrate. Fog, which occurs very often in Pocheon area, was analyzed for its acid components. Conversion from the gaseous sulfur dioxide into sulfate ion is relatively high, $86\~90\%$ while $68\~76\%$ of NOx is converted into nitrate ion form.

A Study of Concentration Prediction of Automobile Air Pollutant Near the Highway (자동차 대기오염물질이 고속도로 인접지역에 미치는 농도 예측에 관한 연구)

  • Park, Seong-Gyu;Kim, Sin-Do;Kim, Jong-Ho
    • Journal of Korean Society for Atmospheric Environment
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    • v.14 no.6
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    • pp.607-620
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    • 1998
  • The influence of transportation on air quality has been elevating in urban area. Air pollutants from automobiles cause primary and secondary air pollution, and need to be tightly controlled. In this study, the effect of automobile air pollutants on highway vicinity area was evaluated by the comparison of field measurement. and target was for modeling using CALINE3, NO2 was the target for this work. It was found that the concentration predicted by CALINE3 is overestimated at low wind speed and input data of wind speed requires correction. Based on the measured data, the wind speed was modified by effective wind speed equation [Ue=U+0.24·EXP(-pxU)], and there after the accuracy of CALINE3 calculation was improved neighborhood area of highway. It was also observed that weather conditions and traffic volume affect the concentration of air pollution. Finally, the NO2 effect of automobile air pollutants on the vicinity area of highway proved to be up to 400∼600m from the highway.

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Air Pollution Trends in Japan between 1970 and 2012 and Impact of Urban Air Pollution Countermeasures

  • Wakamatsu, Shinji;Morikawa, Tazuko;Ito, Akiyoshi
    • Asian Journal of Atmospheric Environment
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    • v.7 no.4
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    • pp.177-190
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    • 2013
  • Air pollution trends in Japan between 1970 and 2012 were analyzed, and the impact of air pollution countermeasures was evaluated. Concentrations of CO decreased from 1970 to 2012, and in 2012, the Japanese environmental quality standard (EQS) for CO was satisfied. Concentrations of $SO_2$ dropped markedly in the 1970s, owing to use of desulfurization technologies and low-sulfur heavy oil. Major reductions in the sulfur content of diesel fuel in the 1990s resulted in further decreases of $SO_2$ levels. In 2012, the EQS for $SO_2$ was satisfied at most air quality monitoring stations. Concentrations of $NO_2$ decreased from 1970 to 1985, but increased from 1985 to 1995. After 1995, $NO_2$ concentrations decreased, especially after 2006. In 2012, the EQS for $NO_2$ was satisfied at most air quality monitoring stations, except those alongside roads. The annual mean for the daily maximum concentrations of photochemical oxidants (OX) increased from 1980 to 2010, but after 2006, the $98^{th}$ percentile values of the OX concentrations decreased. In 2012, the EQS for OX was not satisfied at most air quality monitoring stations. Non-methane hydrocarbon (NMHC) concentrations generally decreased from 1976 to 2012. In 2011, NMHC concentrations near roads and in the general environment were nearly the same. The concentration of suspended particulate matter (SPM) generally decreased. In 2011, the EQS for SPM was satisfied at 69.2% of ambient air monitoring stations, and 72.9% of roadside air-monitoring stations. Impacts from mineral dust from continental Asia were especially pronounced in the western part of Japan in spring, and year-round variation was large. The concentration of $PM_{2.5}$ generally decreased, but the EQS for $PM_{2.5}$ is still not satisfied. The air pollution trends were closely synchronized with promulgation of regulations designed to limit pollutant emissions. Trans-boundary OX and $PM_{2.5}$ has become a big issue which contains global warming chemical species such as ozone and black carbon (so called SLCP: Short Lived Climate Pollutants). Cobeneficial reduction approach for these pollutants will be important to improve both in regional and global atmospheric environmental conditions.

A Study on the Control Performance for Hazardous Gases by Surface Discharge induced Plasma Chemical Process (연면방전의 플라즈마 화학처리에 의한 유해가스제어 성능에 관한 연구)

  • 이주상;김신도;김광영;김종호
    • Journal of Korean Society for Atmospheric Environment
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    • v.11 no.2
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    • pp.185-190
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    • 1995
  • Recently, because of the worse of the air pollution, the excessive airtught of building and the inferiority of air conditioning system, the development of high efficiency air purification technology was enlarged to the environmental improvement of an indoor or a harmful working condition. The air purification technology has used chemical filters or charcoal filters or charcoal to remove hazardouse gaseous pollutants (SO$_{x}$, NO$_{x}$, NH$_{3}$, etc.) by air pollutant control technology, but they have many problems of high pressure loss, short life, wide space possession, and treatment of secondary wastes. For these reason, the object of reasearch shall be hazardous gaseous pollutants removal by the surface discharge induced plasma chemical process that is A.C. discharge of multistreams applied A.C. voltage and frequency between plane induced eletrode and line discharge eletrode of tungsten, platinum or titanium with a high purified alumina sheet having a film-like plane. As a result, the control performance for hazardous gaseous pollutants showed very high efficiency in the normal temperature and pressure. Also, after comtact oxidation decomposition of harmful gaseous pollutants, the remainded ozone concentration was found much lower than that of ACGIH or air pollution criteria in Korea.rea.

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