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MANAGING 21 ST C AIR QUALITY. DISPERSIVE PROCESSES. Mining Waste transfer stations – especially PM 10 in UK. DISPERSIVE PROCESSES. Demolition Vehicle Wear: Cu, Zn, Cd, Sb, Ba, Pb Brakes pads Cu, Ba, Sb. AGRICULTURE. Dispersive sources Ploughing Pesticides Pollen dispersal.
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DISPERSIVE PROCESSES • Mining • Waste transfer stations – especially PM10 in UK
DISPERSIVE PROCESSES • Demolition • Vehicle Wear: • Cu, Zn, Cd, Sb, Ba, Pb • Brakes pads • Cu, Ba, Sb
AGRICULTURE • Dispersive sources • Ploughing • Pesticides • Pollen dispersal
DISPERSIVE PROCESSES Mining, agriculture, construction, roads HNO3 H2SO4 NEUTRALIZATION ORGANICS OXIDATION ORGANIC ACIDS DUST EMISSION
A SENSE OF FAILURE • Re-authorization of CAA(1970) in 1990s • Recognised a failure to meet O3 standards • Noted HC down 30% NOx down 50% • UK things were not getting better- titration • Secondary pollution had detached pollutants from there sources • Seemingly illogical…
RETHINK 96/62/EC SO2 NO2 PM Pb O3 benzene CO PAH Cd As Ni Hg • Human health • Public information Alert • Zones and agglomerations • Technical and scientific support • Working groups and position papers • Methods • Indicative CBA • Daughter Directives and position papers 1,3butadiene HF not included!
CLEAN AIR for EUROPE (CAFE) beyond 96/62/EC • Follows 96/62/EC • but in CAFE - a preoccupation with O3/PM • Concern with environment • and not just health • Synergisms - not pollutant by pollutant approach • Indoor issues – only where it relates to outdoor pollutants
Atkinson Grimshaw Glasgow Docks
YELLOW FOGS Scattering Tar in droplets Gaslight Yoshio Markino- The Painter of Fog
COLOUR OF SMOG Scattering… NO2 brown London fog
SOMETIMES OUTCOMES NOT OBVIOUS In some places the air has become worse in the weekends NO + O3 NO2 + O2
2OPHOTOCHEMICAL POLLUTION CARCINOGENS NEUROTOXIN ENDOCRINE DISRUPTOR TERATOGEN DOMINANCE of the AUTOMOBILE WOOD SMOKE VOCs, O3 COAL SMOKE DIESEL SMOKE SMELLs LEAD H2S POPs TIME
MEXICO CITY STUART FRANKLIN
SEPTEMBER 1986 FUEL CHANGE
ROLE OF “AUTOMOTIVE VAPOURS” CH4 + OH CH3 + H2O CH3 + O2 CH3O2 CH3O2 + NO CH3O + NO2 CH3O + O2 HCHO + HO2 HO2 + NO OH + NO2 CH4 + 2O2 + 2NO HCHO + 2NO2 + H2O …initially scientists thought that the effectiveness of the organic compound would be related to its rate of reaction with OH
PHOTOCHEMICAL OZONE CREATION POTENTIAL (POCP) • However OH reactivity did not capture branching …..where a molecule spilt into two • Ethene (ethylene) typifies this process… CH2=CH2 + O3 CH2O2* + HCHO • Can at times be a hundred fold more reactive than simple organic compounds
CH3 POCP OF AROMATICSBENZENE AND TOLUENE • Benzene and toluene have many double bonds • High POCP • Antiknock additives • Can lead to an effective lachrymator, peroxybenzoylnitrate (PBzN) an aromatic PAN: • C6H5C(O)OONO2 • Mexico city and aromatics
WINTER NOX SMOGS • Termolecular oxidation • Titration NO+O3
WINTER POLLUTION PROBLEMS • Low temperatures favour nitrogen dioxide formation • Cold start gives high carbon monoxide • Stable air masses • Tyre dust
EMISSION CONTROL CONCERN Pollution Emissions …less applicable in an age of secondary pollutants
PRIMARY CONTROL SPORTING EVENTS • Beijing 2008 Olympic Games • Kaohsiung 2009 World Games • London 2012
AIR QUALITY MANAGEMENT POLICY CONCERN Siting issues Air quality standards/goals Emission inventory Monitoring network Meteorological measurement Disagreement Distrust Models! Computer model Devise tactics to meet standards Political wrangle Perceptions Enforce emissions Lower Pollution Economic impact Elsom (1992)
AQM OR EMISSION CONTROL • AQM complex • Control principles • Other methods –financial instruments • Emission trading, permits, fees, fuel tax • CBA
ADVANTAGES • Can control secondary pollutants • Is focused on the heath based issues • Can be flexible in terms of socio-economic strategies
EPAQS & COMEAP • Links between DoH and Air Quality Division
AIR QUALITY MANAGEMENT Air quality standards/goals Emission inventory Monitoring network Meteorological measurement Computer model Devise tactics to meet standards Enforce emissions Lower Pollution
COMPLIANCE – Stationary SourcesROLLBACK AND BEYOND • Clean Fuels • Reduce fuels use – efficiency, better plant • Certification • Zoning • Architectural coatings
COMPLIANCE - AutomobilesROLLBACK AND BEYOND • Reduce total emissions • Speed, pooling, public transport, urban planning • Reduce vehicle emissions • Cleaner engines, fuels catalytic converters • Maintenance and inspection • certification
EUROPEAN CONTROLS • Ever tightening regulations as part of a recognition of the role of motor vehicles
DIESEL PRIMARY NO2 • EURO III diesel cars have oxidation catalysis and particle traps • This now means the emission ratio for NO2/NOx is 50% rather than 5% in the past…
METHANOL • potential alternative to a hydrogen economy • production via syngas from natural gas • CH4 + H2O → CO + 3H2 nickel catalyst 850°C • CO + 2H2 → CH3OH copper, zinc oxide, and alumina @5–10 MPa and 250 °C • good motor fuel
METHANOLMODELLING IMPACT IN A LARGE CITY • Peak 1h ozone likely to change little • More general O3 improvements though… • PAN reduced • Increased peak HCHO, but average does not change much • Toxicological problems
LEZ • EURO3 • PM • 2012 Minibus
Bush and Lula (Brazil) on Biofuel 9 Mar 07 BIOFUELS • The European Union biofuels directive: • 2010 at least 5.75% biofuel usage for traffic fuel. • 2020 10 % • Backed down 2008 http://news.bbc.co.uk/1/hi/world/europe/7186380.stm • George W. Bush 2006 State of the Union speech: US to replace 75% of the oil it imports from the Middle East by biofuels by 2025
SECONDARY ORGANIC AEROSOL • Recognising that the organic material formed in the smog was important • Oxidized compounds, but necessarily non volatile – e.g. dicarboxylic acids
DIESEL PARTICLES • Increasing concern about very fine particles black diesel vehicles • Nitration of organics • Carcinogens
Los Angeles ULTRAFINES (50-100nm) Most abundant catalytic metals: Fe, Ti, Cr, Zn, Ce Some 10% of primary organic particles seem to be from cars... Cass et al Phil. Trans. 2000
toxaphene Aldrin Chlordane DDT Dieldrin endrin, heptachlor Hexachlorobenzene mirex polychlorinated biphenyls polychlorinated dibenzo-p-dioxins polychlorinated dibenzofurans PERSISTENT ORGANIC POLLUTANTS (POPS) Compounds resistant to environmental degradation UNEP short list of 12