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Preparation of Fine Particulate Emissions Inventories. Lesson 1 Introduction to Fine Particles (PM 2.5 ). What will We Discuss in Lesson 1?. After this lesson, participants will be able to describe: the general composition of fine particulate matter in the atmosphere
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Preparation of Fine Particulate Emissions Inventories Lesson 1 Introduction to Fine Particles (PM 2.5 )
What will We Discuss in Lesson 1? • After this lesson, participants will be able to describe: • the general composition of fine particulate matter in the atmosphere • how fine particulate matter are formed • typical composition of ambient air in 2 western areas • sources that contribute to the formation of fine particulate matter, nationally and in this area
Why is This Information Important? • This information • puts the local inventory efforts in perspective, • shows how source types fit into the overall accounting of PM2.5 • provides a foundation for setting inventory priorities in your area
PM2.5 Composition • Definitions • Crustal ~ Metallic oxides in earth’s crust • Fugitive Dust ~ Crustal matter emitted into the air directly, not thru a stack or vent. • Sulfate ~ H2SO4 (condensed), (NH4)HSO4 (NH4)2SO4 • Nitrate ~ NH4NO3 • Organic Carbon ~ OC • Organic Matter ~ OC + the associated O & H • Elemental Carbon ~ EC • Primary ~ Directly emitted • Secondary ~ Formed in air from precursor gases (generally considered to be all PM2.5)
Why is Ambient Composition Important? • Identifying important source types on days with high PM2.5 concentration • Help prioritize inventory efforts • Carbonaceous vs. Crustal • Sulfate vs. Nitrate • Role of Ammonia • Help in benchmarking the validity of the EI
PM2.5 Composition (cont’d) • Other characteristics: Sulfate, Carbon & NO3 • Sulfate forms slowly, over long distances • Sulfate patterns relatively “flat” over large regions. • Regionally disbursed sources • Carbon has both regional & urban components • High Nitrate concentrations are usually • more localized • tend to form in urban areas, or • where abundance of animal or fertilizer NH3
PM2.5 Composition Varies Across U.S. Northwest Midwest Southeast Sulfate Nitrate EC OC Crustal
Mid-Atlantic Area Air Quality in More Detail • Maryland • Baltimore County • Kentucky • Pennsylvania • Allegheny Co • Northampton County • Lancaster County • Delaware County • Philadelphia County
Composition of PM2.5 in Baltimore Co, MD BALTIMORE 240053001
Composition of PM2.5 in Allegheny Co, PA PITTSBURGH 420030008
Composition of PM2.5 in Northampton Co, PA BETHLEHAM 420950025
Composition of PM2.5 in Lancaster Co, PA LANCASTER 420710007
Composition of PM2.5 in Delaware Co, PA PHILADELPHIA 420450002
Composition of PM2.5 in Philadelphia Co, PA PHILADELPHIA 421010004
Composition AND Urban Excess • Components of PM are higher in the urban area than in the surrounding area • Urban Excess is that part of the urban AQ that is higher than in surrounding areas • Simplistically, urban excess is assumed mostly associated with urban sources ENFI 2007
Urban Excess Concept in Mid-Atlantic Excess of OC and Nitrate PM 2.5 (esp in Winter) in Urban Areas of Mid Atlantic http://www.cambridge.org/us/catalogue/catalogue.asp?isbn=0521842875
Atlanta, GA / Ring of Rural Locations 10 Bottom: Regional Contribution Top: Urban Excess 8 6 ug/m3 4 2 0 Sulfate Est. Ammonium Nitrate EC+OC Crustal “Urban Excess” in Atlanta, GA Rural Monitors used for Comparison ( + ) Draft Analysis
What are the Key Source Types Emitting PM2.5 and it’s Precursors (Nationally)? 2005 Nat’l Emissions (1000 short tons) Source Category PM2.5 NH3 NOx SO2 VOC FUEL COMB. ELEC. UTIL. 508 27 3,856 10,469 48 FUEL COMB. INDUSTRIAL 178 17 2,042 1,784 152 FUEL COMB. OTHER 421 17 733 578 1,375 CHEMICAL & ALLIED PRODUCT MFG 30 23 70 259 249 METALS PROCESSING 54 3 69 213 46 PETROLEUM & RELATED INDUSTRIES 18 3 354 257 601 OTHER INDUSTRIAL PROCESSES 354 177 429 327 442 SOLVENT UTILIZATION 7 0 7 0 4,278 STORAGE & TRANSPORT 23 1 19 5 1,484 WASTE DISPOSAL & RECYCLING 268 26 111 26 395 HIGHWAY VEHICLES 127 307 6,407 145 4,078 OFF-HIGHWAY 292 3 4,403 516 2,858 MISCELLANEOUS 3,256 3,539 211 135 3,970 TOTAL 5,536 4,143 18,711 14,714 19,976
Overview of PM2.5 Sources in NE U.S. • PM2.5 (OC, EC, Ammonium Nitrate and Sulfate, Crustal) • Open Fires (primary OC, EC, VOC, NOx & NH3) • Open burning, land clearing debris, prescribed fires • Motor Vehicles (NOx, VOC, NH3, OC, EC) • Non road emissions (NOx, VOC, NH3, OC, EC) • aircraft, lawn, construction, and agricultural equipment. • Residential Wood Combustion (OC, EC, VOC) • Boilers (OC, EC, VOC, NOx, SO2, some crustal) • Fugitive Dust (mostly crustal, some OC, EC) • More ~ Anti-skid sanding, Construction • Lesser ~ Agriculture, unpaved roads, windblown dust
Overview of PM2.5 Sources in NE U.S. • PM2.5 (Crustal, OC, EC, Ammonium Nitrate) • Misc VOC Sources (precursor to secondary OC) • household and industrial products, such as paints and varnishes, cleaners, disinfectants, and degreasers. • Fuel combustion and the handling and distribution of fuel • Dairies and other livestock waste • Open Burning and Prescribed fires • Misc Ammonia Sources (precursor to ammonium nitrate) • Livestock wastes from dairies and agricultural operations
Mid-Atlantic Area 2005 PM 2.5 Emissions (TPY) Note: Anthropogenic VOC (Biogenic VOC > Anthropogenic VOC in Mid Atlantic, SE US)
Mid-Atlantic Area 2005 PM 2.5 Emissions (TPY) Note: Extent of Ag Biomass Waste Burning is not fully understood
Crustal Material – Sources & Composition • Fugitive Dust ~ Main source of Crustal • Unpaved roads • Anti-skid materials on paved roads • Agricultural tilling, dairies • Wind-blown dust • Construction • Fly ash • Composition of Fugitive Dust ~ a mixture of: • “earth oxides” (e.g., oxides of Ca, Al, Si, Fe & Ti) • carbonaceous material (EC, OCM)
Speciation of Crustal • “Speciation” ~ process of estimating the components of the sample, e.g., crustal by using the chemical characteristics of the sample: Crustal% = C1Al% + C2Ca% + C3Si% +C4Fe% + C5Ti% where Al%, Ca%, Si%, Fe% & Ti% are these species % of the sample’s mass • Speciation can be done on both ambient measurements AND emissions • More about emissions speciation later
Carbonaceous Material – “Matter” • Ratio of OC to EC changes with source • Mobile Sources Gas: 5 - 15 • Mobile Sources Diesel: 0.4 • Open Fires: 10 - 12 • Residential Wood Burning: 7 - 8 • Fugitive Dust: 15 - 25 Hannaford 2009
Organic Carbon “Matter” (OCM) Emissions • “Matter” is the O and H that are part of the OC molecule • The OC measurement must be “augmented” to account for the “matter” • Augmentation of Primary (Fresh) Emissions • augmentation done using a multiplier – • OCM = C * OC • C(E) = 1.2 to 1.8 (depending on source type) • C(E) applied in Emissions processor *C(E) values documented in Reff 2009 • Augmenting Aged Aerosol -- C(E) = 1.8 - 2.4 (depends on aging, other factors)
Organic Carbon “Matter” (OCM) Emissions • Aerosol Aging and Secondary Formation: • 2 aging / formation processes: • 1st – particles oxidize as they “age” • 2nd – additional “secondary” particles form • AQ Models age the aerosols and account for the formation of secondary organic carbon • In ambient aerosols, the C(A) can be as high as 2.4 • ambient OC includes secondary formation (which has a high matter content) and • aerosol aging by oxidation, which adds O and H “matter”
Let’s Review and Summarize • A Complex Mixture • Speciated Ambient Data • Composition • Primary vs. Secondary • Key Sources • Composition by source type • Directly emitted vs. precursors
Review of Important PM2.5 SourceCategories PRECURSOR EMISSIONS DIRECT EMISSIONS Combustion SO2 NH3 a, b c Open Burning (all types) Power Gen (Coal) On-Road Mobile Non-Road & On-Road Mobile Boilers (Coal) Animal Husbandry Residential Wood Burning Power Gen (Oil) Fertilizer Application Wildfires Boilers (Oil) Wastewater Treatment Power Gen Industrial Processes Boilers Boilers (Oil, Gas, Coal) Boilers (Wood) VOC d NOx Biogenics Crustal / Metals On-Road Mobile (Gas, Diesel) b Solvent use Power Gen (Coal) Fugitive Dust On-Road (Gas) Non-Road Mobile (Diesel) Mineral Prod Ind Storage and Transport Boilers (Gas, Coal) Ferrous Metals Residential Wood Residential (Gas, Oil) Petrochemical Industry Industrial Processes Waste Disposal NOTE: BOLD Categories in a Includes primary organic particles, elemental carbon and condensible organic particles; also some flyash b Impact of carbonaceous emissions on ambient PM 5 to 10 times more than crustal emissions impact are most important nationally. Their c Includes SO , and SO and H SO condensible inorganics relative importance varies among and 2 3 2 4 d Contributes to formation of secondary organic aerosols between urban and rural areas.
Questions? Typical Haze in the Blue Ridge Mountains TPace 2009