air pollution ? meteorology chemistry photochemical smog aerosol visibility reduction diffusion acid...

Air pollution ?

Meteorol-ogy

Chem-istry

Photochem-ical Smog

Aerosol

Visibility reduction

Diffu-sion

Acid rain

Ozone hole

Deposi-tion

Trans-port

Gas pol-lutant

출처 : 위키피디아 Library of Congress CALL NUMBER LC-USW36-376, reproduction number LC-DIG-fsac-1a35072

출처 : Martin Bernetti AFP/ Getty images

Increase of scale

Local scale City scale Regional scale Global scale

Emission TransportRemoval

1. Effects and sources of air pollutants

1.1 Definition of air pollution오염물질이 인간 , 동 · 식물 및 재산에 유해하거나 인간의 쾌적한 생활을 방해할 정도의 양으로 대기 중에 존재하는 상태

1.2 Air pollution Episodes

• Meuse valley :Belgium December 1930 Severe three-day fog 60 people died• Dorora: United States October 1948 Four-day fog 20 persons died• London smog: 1952 December 5-8, Four-day fog 4000 persons died 1956: clean air actSmog=Smoke+fog

• LA smog: photochemical smog Hydrocarbon, nitrogen oxides, sunlight LA is located in low basins surrounded by moun-tains

출처 : Wongfuphil.wordpress.com

1.3 General listing of air pollutants

1) Concentration Units

1ppm: 1 volume of gaseous pollutant/106 volume (pollutant+air)g m-3

2) Classification of air pollutant

• General classificationParticulate mattersSulfur containing compoundOrganic compoundNitrogen-containing compoundCarbon monoxideHalogen compoundsRadioactive compoundsPhotochemical oxidantsOther inorganic compounds

• Classification based on originPrimary pollutant: those emitted directly from sources ex) SO2, CO

Secondary pollutant: those formed in the atmosphere by chemical reactions ex) NO2, O3

1.4 Particulate matters (Aerosol)

• Definition: 대기 중에 부유하고 있는 액상과 고체상의 입자들 • Size: 0.0002m-500m• Particles less than 0.1 m : Brownian motions• Particles between 0.1 and 2m: removed by rainout and

washout• Particles larger than 20m: large settling velocity removed from the air by gravity and inertial processes

Measurement: high volume sampler, PM10 sampler

TSP: total suspended particulate matter PM10: the particulate matter which diameter is less than 10 m. Damage to respiratory organ : fine particle (d<2.5m) Visibility reduction : principally affected by fine particles

Aerodynamic diameter: the diameter of a sphere of unit den-sity (1g cm-3) that has the same terminal gravitational settling velocity in still air as the actual particle in question

1-5 Carbon monoxide

• Colorless, odorless gas• A lifetime of 2 to 4 months in the atmosphere• Natural source: oxidation of methane, biomass burning• Anthropogenic source: vehicle• minor role in photochemical reaction leading to ozone

formation• Effect on health: reduce the oxygen-carrying capacity

of the blood

1-6 Sulfur oxides

• SO2 (sulfur dioxide), SO3 (sulfur trioxide)

• SO2: nonflammable, nonexplosive, colorless gas

• SO2 -> Sulfuric acid

• Acid rain ( 한반도 pH ~5, Cl-> SO42-> NO3

- : 2012 대기환경연보 )

• : Acid rain pH<5.6• Long range transport• Sulfate: pronounced reduction in visibility

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1.7 Effects of hydrocarbons, Oxides of nitrogen, photochemical oxidants 

1-7-A Hydrocarbon ( 탄화수소 )• Organic compounds composed of hydrogen and carbon• Alkanes (CnH2n+2): RH ex) Methane (CH4), ethane (C2H6)

• R alkyl radical (CnH2n+1)

• Alkenes (CnH2n) :double bond

• Alkyne (CnH 2n-2): triple bond

• Aromatics : Benzene (C6H6), Toluene, Xylene

• Hydrocarbons, in combination with the oxides of nitrogen in the presence of sunlight, form photochemical oxidants

• No direct adverse effects upon human health• Radical: 적어도 한 개 이상의 쌍을 이루지 못한 전자를 갖고 있는

원자나 분자• Ex) Alkyl radical CnH2n+1

• VOCs: volatile organic compounds• The entire set of vapor phase atmospheric organics

excluding CO and CO2

1-7-B Oxides of nitrogen

• Nitric oxide (NO), Nitrogen dioxide (NO2), nitrous oxide (N2O), NO3, N2O3, N2O4, N2O5

 • NOx: NO+NO2

• NOy: the sum of the reactive oxides of nitrogen and all other compounds that are atmospheric products of NOx.

• NOx, HNO3, HNO2, nitrate radical (NO3), N2O5, PAN (N2O, NH3

는 아님 )• NO2: the highest concentration in ambient air

Absorbs visible light Photochemical smog Nitric acid (HNO3) -> acid rain

1-7-C Photochemical oxidants

• Ozone(O3), Peroxyacetyl nitrate (PAN), Hydrogen peroxide (H2O2), formic acid (HCOOH) etc

• The products of atmospheric reactions involving VOCs, NOx and radical and sunlight

• VOCs: volatile organic compounds

• Secondary pollutant• Photochemical smog: high concentration of photochemical

oxidants Marked reduction in visibility Brownish sky

1-8 Sources of air pollutants

• Emission inventory : the study conducted to determine the emission of particular pollutant done through the use of emission factor

• emission factor: typical emissions that are emitted by a particular source type based on the specific pollutant, type of process, age, size, type of control technology.

• Major anthropogenic sources: transportation, fuel combustion (stationary source), industrial process.

대기환경연보 2012

대기환경연보 2012

대기환경연보 2012

1-9 Global issues related to air pollution

• Acid rain, global warming, stratospheric ozone hole

1) Global warming• Greenhouse effect: 대기가 태양의 단파복사를 거의 투과시키고

지구의 장파복사는 흡수 재 방출시킴으로써 지표면의 온도를 지구 복사평형온도보다 높게 만드는 효과

• Greenhouse gas : water vapor, carbon dioxide, methane, nitrous oxide (N2O), CFCL3 CF2Cl2

• Kyoto protocol: International framework convention on climate change with the objective of reducing greenhouse gases in an effort to prevent anthropogenic climate change

• Signed in 1997• Entered into force in 2005• Industrialized countries (37) reduce collective emissions of

greenhouse gases by 5 % against 1990 levels over the five-year period 2008-2012.

• CO2, CH4, N2O, HFC, PFC, SF6

2) Stratospheric ozone hole

The presence of ozone in the lower stratosphere produces a very beneficial effect by absorbing a significant amount of the short wavelength ultraviolet radiation. Ozone hole in the stratosphere over Antarctica in spring (October)  Montreal protocol (1987) : International agreement among nations designed to protect the ozone layer by phasing out the production of a number of substances (CFCs) believed to be responsible for ozone depletion.

대기환경 연보 2012

대기환경 연보 2012

전국 대기오염측정망 설치현황 (‘12 년 12 월말 기준 )

NO CompoundsMolecu-

lar weight

B.P (°C) NO Compounds

Molecu-lar

weight

B.P (°C) NO Compounds

Molecu-lar

weight

B.P(°C)

1 Benzene 78.1134 80.1 6 o-Xylene104.151

2145.2 11 1,1-Dichloroethane 98.96 57-59

2 Toluene 92.1402110.

67 Chloroform 119.38 61.0 12

Carbon tetrachlo-

ride153.82 76-77

3Ethylben-

zene106.167

136.

28

MethylChloro-

form133.41 74-76 13 1,3-Butadiene 54.09 -4.4

4 m,p-Xylene 106.167138.

39

TriChloroethy-

lene131.39 86.7

5 Styrene 106.167139.

110

Tetrachloroethy-

lene165.83 131.3

분석대상물질 (VOC 13 종 )

대기환경 연보 2012

연도별 SO2 연평균 농도분포

대기환경 연보 2012

연도별 NO2 연평균 농도분포

대기환경 연보 2012

연도별 O3 연평균 농도분포

대기환경 연보 2012

연도별 CO 연평균 농도분포

대기환경 연보 2012

연도별 PM-10 연평균 농도분포

대기환경 연보 2012

주요도시의 월평균 농도

대기오염 관련 Web Site

국내 site• Library.me.go.kr: 환경부 지식 포털 • www.nier.go.kr: 국립환경과학원• erip.nier.go.kr: 환경연구종합정보 서비스

외국 sitewww.epa.gov