SOURCES OF AIR POLLUTANTS
COURSE COMMUNICATION l l Timetable: l l Open office
ASSESSMENT l Non graded problem sheet literary seminar presentation for Journalistic essay 16th March(?) l Journalistic essay – New Scientist style Introduced 30 Jan and due March ?? l Exam
FUELS as HYDROCARBONS l Hydrogen and other fuels l Fate of carbon and hydrogen in combustion l Effect of oxygen limitation l Smoke l PAH
PAH l Condensation in flames l Optimum temperatures in wood burning relatively low
GHOST MONEY Ghost month = smoke month 90,700 tonne of money are burned burning paper money releases benzene or furfural? ~27 kg BaP (if furnaces) cf UK kg/annum July 2008: EPA sealed a Land God Temples ( ) furnace in Bade Village ( ) Lungtan Township ( ),
NITROGEN and AIR l Zeldovic cycle N+ O 2 l Prompt nitrogen CH + N 2 HCN + N HCN CN NO l Oxygen balance different for CO and NO
AUTOMOTIVE EMISSIONS Balancing carbon and nitrogen l l CO + O 2 CO 2 N 2 + O 2 N O
NO 2 l l Satellite images show strong association with cities – especially motor vehicles
SULFUR EMISSIONS l Sulfur as an impurity in fuel l High sulfur coals l Higher in fuel oils- low in petrol l l Globally emissions from ships are an increasing source sulfur
CHLORINE CHEMISTRY l Coal and wood can have high chlorine concentrations. Emissions as HCl (or CH 3 Cl) HCl HNO 3 H 2 SO 4 10 hours 25 hours
DAMAGE TO CARS Paintwork exposed to simulated raindrops SALT RAIN WITH RUST ACID RAIN WITH RUST ACID RAIN pH 3.7 salts accumulate on rust particles DISCOLOURATION 1 mm Mark Guishard
NITRO/CHLORO/SULFUR PAH
METALS IN PARTICLES – IMPURITIES IN FUELS l Vanadium l Nickel …so we get V 2 O 5, V 2 O 4, V 2 O 3 and even 2NiO.V 2 O 5 l l Porphyrins combine readily with metals
ADDITIVES l Boron l Chlorine – lowers PAH? l Tetra ethyl lead The C-Pb bond is quite weak, so fragments producing lead and C2H5 radicals which can help terminate the combustion process by radical reactions.
METHYLCYCLOPENTADIENYL MANGANESETRICARBONYL (MMT) l Approved by US-EPA at 1ounce per gallon of gasoline for street-vehicles l Fears of links between manganese and brain damage l Battle between Ethyl Corp and EPAs
l Even after coal - still an urban problem l Diesel – unburnt carbon l Less that 10 or even 2.5 m FINE PARTICULATE MATTER Phillip Tan
BRICKMAKING l K 2 Al 4 (Si 6 Al 2 O 20 )(OH) 4 + SiO 2 2KAlSi 3 O 8 + 2Al 2 SiO 5 + 2H 2 O l K 2 Al 4 (Si 6 Al 2 O 20 )(OH) 2 F 2 + SiO 2 2KAlSi 3 O 8 + 2Al 2 SiO 5 + 2HF muscovite silica sillimanitemicrocline
INCINERATORS l Metals – mercury! l SO 2 from fuel l NO l HCl from PVC etc l Dioxin… how to make
SUDBURY l Ni 2 S 3 + 4O 2 2NiO + 3SO 2
CELEBRATING POLLUTION
DEMOLITION Building dusts – lots of trace contaminants
AGRICULTURE l Dispersive sources Ploughing Pesticides Pollen dispersal
DISPERSIVE PROCESSES ORGANICSORGANIC ACIDS NEUTRALIZATION HNO 3 H 2 SO 4 DUST EMISSION Mining, agriculture, construction, roads OXIDATION
VEHICLE WEAR l Wear: Cu, Zn, Cd, Sb, Ba, Pb l Brakes Cu, Ba, Sb l Diesels Ba, Sb
ASIA - MOTORCYCLES l Traditionally 2-stroke engines lots of organic matter and particles – with organic material l Electric power l Air power
EUROPEAN CONTROLS l Ever tightening regulations as part of a recognition of the role of motor vehicles
CARBON FOOTPRINT ALSO