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What’is “emission” ?. Simple Definition; “Release of pollutants into the air from a source.”. “The release or discharge of a substance into the environment. Generally refers to the release of gases or particulates into the air.”. İmmission (don’t confuse!)
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What’is “emission” ? Simple Definition; “Release of pollutants into the air from a source.” • “The release or discharge of a substance into the environment. Generally refers to the release of gases or particulates into the air.” İmmission (don’t confuse!) The level of a particular pollutant in the environment. Widely used for air emissions and noise
Sources of air pollution • Point sources • A point source is a stationary source that can best be described as a manufacturing plant or a similar entity having one or more emissions units discharging air emissions into the atmosphere, and located at one specific geographic area. • Area sources • An area source is also a stationary source that is not included in the point source inventory. • Line sources • A mobile source is a moving source that emits air pollutants. Source: http://www.epa.state.oh.us/dapc/aqmp/eiu/eiu.html
Emissions of primary air pollutants Nitrogen oxides emissions in the UK in 1998.1753 thousand tonnes (NO2 and NO) Sulphur dioxide emissions in the UK in 1998.1615 thousand tonnes Source; http://www.ace.mmu.ac.uk/eae/english.html
What’is an emission inventory? • Simple definition; “An emisisoninventory is an estimation of airpollution” • “An emissionsinventory is a detailedlisting of pollutantemissions, andtheircalculatedemission rate estimates, as identifiedfromspecificsourcesin a givengeographicareafor aspecified time period. (baseyear..etc.)” Source: http://www.epa.state.oh.us/dapc/aqmp/eiu/eiu.html http://www.baaqmd.gov/pln/emission_inventory.htm
Emission Inventory • Information fromsourceidentifications is compiledinto a comprehensivereportinventoryingsources, activitiesandpollutants. • Presentandfutureyearinventoriesarecriticalcomponents of airqualityplanningandmodeling. • Thesourcemay be a utility, refinery, automobile, train, etc. Eachtype of source can be placedinto a point, area or mobile sourcecategory.
Emission inventories are used for a wide variety of purposes, but are most often developed in response to regulation. Emissioninventoriesareused • forvariouspolicy-makingpurposes, • characterization of temporalemissiontrends, • trackingtrends in emissionsover time. • toassesstheeffectiveness of airpollutionpolicy, • development of urban strategies, • emissionsbudgetingforregulatoryandcompliancepurposes, • prediction of ambientpollutantconcentrationusingairdispersionmodels (as inputtoairqualitymodels) • as inputtoexposureand risk assessments
An emissioninventorycontainsthefollowinginformation. • Tabular summary of emissionestimatesbysourcecategory • Background information, includingthereasonsforcompilingtheinventory • Geographicareacoveredbytheinventory • Time intervalrepresentedbytheemissioninventory (forexample, annual, seasonal, hourly) • Population, employment, andeconomic data usedtoestimateandallocateemissions • proceduresusedtocollectthe data, sources of data (where data areacquired), copies of questionnairesandresults, andcitationsforallemissionfactors • Identification of methodsusedtocalculateemissions, includingexamplecalculations • Complete documentation of allassumptionsmade • Identification of emissionssources not included in theinventory • List of references
How do I develop an air toxics emission inventory for my local area? What is thepurpose? • Toassesspublichealth risk, • Tofocus on subsequentinventoryimprovementwork, • Todevelopcontrolstrategiesandnewregulations.
A goodlocalscreening is vital (1) whatpollutants, sourcecategories, andgeographicareasshould be included; (2) therelativeimportance of major, area, and mobile sources; and (3) whetheryou can basetheinventory on existinginventories, permitfiles, andothersources of information, such as upsetormalfunctionreports, Risk Management Plans, andtheToxicRelease Inventory (TRI).
Emission Inventory • Inventory should be as accurate as possibleandthatitsuncertainties be wellunderstood,sothatdecisions can be made on a soundbasis. • Iftheexistinginventory is not adequate, substantialimprovementsmay be possiblebyusinglocal-scale data. • An improvedinventorywillprovidemoreaccurateinformation as well as an understanding of thelevel of uncertainty of emissionsestimatesforeachcategory. • An emissioninventoryincorporatingdetailedlocalinformation is likelytoreflectlocalconditionsmoreaccuratelythanonedeveloped on thebasis of general nationalinformation. • Anotherbenefit of a moreaccurateemissioninventorypertainstotheassessment of health risk.
Emission Inventory Techniques Todevelop an emissioninventoryfor an area, onemust • Listthetypes of sourcesforthearea, such as automobiles… • Determinethetype of airpollutantemissionfromfromeach of thelistedsources, such as PM, SO2, NO2… • Findvalidemissionfactorsforeach of thepollutants • Through an actualcount, orbymeans of someestimatingtechnique, determinethenumberand size of specificsource in thearea • Multiplytheappropriatenumbersfromandtoobtainthe total emissionsandthensumthesimilaremissionstoobtainthe total forthearea.
A typicalexamplewillillustratetheprocedure. Supposewewishtodeterminetheamount of CO fromcoalfurnaceemittedperday, duringtheheatingseason, in a smallcity of 500.000 population: • Thesource is coalfurnaceswithintheboundaryarea of thecity. • Thepollutant of concern is CO • Emissionfactorsfor CO arelisted in variousways (240 gram pertone of coal) • coalsalesfigures, obtainedfromthelocaldealersassociation (400 ton perday). • 240 gram CO/ton*400 tones/day=96 kg CO/day
Calculation of emission EQUATION E = A x EF where, E = emissions (amount of SO2 etc) A = activity data (liters of fuel, kg of cement) EF = emission factor (kg CO2/liter of fuel, kgCO2/kg cement) Source: http://cd4cdm.org/countries%20and%20regions/Asia/Philippines/Training%20Workshop/erc/overcarbon.ppt
E = A x EF A (activity data) - data on the magnitude of human activity resulting in emissions or removals taking place during a given period of time (liters of fuel consumed, etc) EF (emission factor) - a coefficient that relates the activity data to the amount of chemical compound which is the source of later emissions. - Emission factors are often based on a sample of measurement data, averaged to develop a representative rate of emission for a given activity level under a given set of operating conditions. (amount of Carbon/unit activity) Source: http://cd4cdm.org/countries%20and%20regions/Asia/Philippines/Training%20Workshop/erc/overcarbon.ppt
Sample Emissions Calculation (for coal consumption) For Eskibağlar Mahallesi Emission rate= (amount of coal burned in stovesx Emission factor) + (amount of coal burned in boilersx Emission factor) Imported coal PM =[(0,98 x 5977 ton/yıl x 2 kg/ton) + (0,02 x 5977 ton/yıl x 5 kg/ton)] x (1 ton/103 kg)= 12 ton/yıl SO2 =[(0,98 x 5977 ton/yıl x 4 kg/ton) + (0,02 x 5977 ton/yıl x 25,93 kg/ton)] x (1 ton/103 kg)= 26 ton/yıl CO =[(0,98 x 5977 ton/yıl x 38 kg/ton) + (0,02 x 5977 ton/yıl x 0,3 kg/ton)] x (1 ton/103 kg)= 223 ton/yıl VOC=[(0,98 x 5977 ton/yıl x 0,2 kg/ton) + (0,02 x 5977 ton/yıl x 4 kg/ton)] x (1 ton/103 kg)= 2 ton/yıl NOx=[(0,98 x 5977 ton/yıl x 2,3 kg/ton) + (0,02 x 5977 ton/yıl x 1,5 kg/ton)] x (1 ton/103 kg)= 14 ton/yıl Soma Lignite PM =[(0,98 x 2878 ton/yıl x 3 kg/ton) + (0,02 x 2878 ton/yıl x 40 kg/ton)] x (1 ton/103 kg)= 11 ton/yıl SO2 =[(0,98 x 2878 ton/yıl x 12 kg/ton) + (0,02 x 2878 ton/yıl x 24,37 kg/ton)] x (1 ton/103 kg)= 35 ton/yıl CO =[(0,98 x 2878 ton/yıl x 25 kg/ton) + (0,02 x 2878 ton/yıl x 137,5 kg/ton)] x (1 ton/103 kg)= 78 ton/yıl VOC=[(0,98 x 2878 ton/yıl x 0,5 kg/ton) + (0,02 x 2878 ton/yıl x 0,015 kg/ton)] x (1 ton/103 kg)= 1 ton/yıl NOx=[(0,98 x 2878 ton/yıl x 2,1 kg/ton) + (0,02 x 2878 ton/yıl x 2,9 kg/ton)] x (1 ton/103 kg)= 6 ton/yıl
Sample Emissions Calculationfortraffic Calculation of emissions from gasoline powered vehicles (government vehicles) Emission rate (annual base)= kilometers traveled per year x number of vehicles x emission factor (EF) PM = (20 km/day x 250 days/year) x 571 vehicles x 0,029 g/km x 1ton/106 g = 0,082 ton/year SO2 = (20 km/gün x 250 gün/yıl) x 571 araç x 0,111 g/km x 1ton/106 g = 0,317 ton/year CO = (20 km/gün x 250 gün/yıl) x 571 araç x 1,688 g/km x 1ton/106 g = 4,819 ton/year VOC = (20 km/gün x 250 gün/yıl) x 571 araç x 0,135 g/km x 1ton/106 g = 0,385 ton/year NOx = (20 km/gün x 250 gün/yıl) x 571 araç x 0,314 g/km x 1ton/106 g = 0,896 ton/year ( *) Government cars are not traveling at weekends.
PREPERATION OF EMISSION INVENTORIES AND GIS SUPPORTED MAPPING OF AIR POLLUTION IN ESKISEHIR Anadolu University, Eskişehir Hicran Çınar*, Ozan Devrim Yay, Tuncay Döğeroğlu *Res. Asst., Anadolu University - Environmental Engineering - hcinar@anadolu.edu.tr
Objective of the study • To calculate the emissions due to combustion, • To investigate the contribution of residential heating, traffic and industrial fuel consumption to the air pollution in urban Eskişehir and • To make a visual evaluation of the spatial distribution of emissions on the study area by generating pollution maps using GIS.
Study area Industrial region Population (2002): 504.724 kişi ; Area: 123,1 km2 (EOIR: 22 km2); Population density: 4.998 capita.km-2; Number of districts: 65; Number of homes: 175.280 ; Number of industrial facilities in EOIR: 198
Pollutants included • PM • SO2 • CO • VOC’s • NOX
Selected pollutant sources • Homes (residential heating) area source • Motor vehicles (exhaust emissions) line and area source • Industrial facilities, EOIR (combustion of fossil fuels) point and area sources • Industrial and non-industrial facilities in town center which use great amount of fuel (combustion of fossil fuels) point sources
Literature review Classification of pollutant sources Collection of required data for calculations Determination of convenient emission factors(Corinair, EPA) Calculation of emissions Prepare tables and graphics to understand inventory results more easily Mapping with GIS (Geomedia Professional 4.0, Surfer, Image Analyst, MFworks ) Assessment of the inventory results, compare the results with that of other cities Methodology 1. Planning 2. Progress 3. Assessment
Residental heating characteristics Soma lignite Coal Natural gas Natural gas Natural gas Coal ımported coal Fuel Consumption for 2002 Natural gas : 105,667,582 m3 (ESGAZ) Imported coal : 144,000 tons (calculated) Soma lignite : 69,000 tons (calculated)
Emission factors • Residential heating; * Stoves: Durmaz et. al 1994 * Boiler system: EPA (Imported coal:1996, Lignite: 1998 and natural gas: 1998) • Traffic; * CORINAIR, 2002 • Industrial fuel consumption; * EPA,1998
Findings Emission estimates for 2002 (tons.year-1)
Contribution of differentsourcegroupstothe total annualemissions 2002 of Eskisehir 881.1 tons.year -1 2467.4 tons.year -1 9146.5 tons.year -1 404.9 tons.year -1 3064.6 tons.year -1 Residential – Soma Lignite Traffic Point sources Residential – Natural gas Residential – Imported coal Organised Industrial Region Consumption of imported coal and Soma lignite for residential heating is important for the formation of PM, SO2 and CO emissions. Also, traffic is playing an important role in the formation of VOC and NOx emissions. Share of expected annual ambient air emissions caused by natural gas consumption for industrial use and residential heating is less than other sources. Here, advantages of using natural gas is observed.
Estimated emissions for traffic related sources, 2002 (tons.year-1) Equations Line sources are resposible for approximately 20% of total traffic emissions * For line sources, substantial countings of vehicles on site had been conducted to determine traffic flow and vehicle type mixture. Data about vehicle countings of morning and evening peak hours on 22 major arterias and 8 counting stations in the weekdays at were gathered from the Eskişehir Major Transportation Plan.
Distribution of traffic related emissions Emissions from diesel traffic vehicles (buses,trucks ..) contribute most to air pollution. PM = 110 tons.year -1 SO2 = 744 tons.year-1 Total number of vehicles in 2002; : 84025 Automobile 75% Minibus 2% Bus 1% !! Great amount of emissions! Van- small truck 13% Truck 9% CO = 1214 tons.year -1 VOCs = 235 tons.year -1 NOx = 1901 tons.year -1 Buses are responsible for 39,4 % of total NOx emissions. (including all sources) Trucks are responsible for 32,6 % of total VOC emissions in Eskişehir.
Interpolation+ Overlay Distribution of residential heating and traffic related SO2emission estimates for 2002 (tons.km-2.year-1)
Results and Discussion • Arranging pollutants according to their annual • emissions; • CO > NOX > SO2 > PM > VOCs • Arranging pollutant sources according to their annual • emissions; • Residential heating > Traffic > Industry
Results and Discussion • Assessment according to pollutant- source relationship • Consumption of imported coal and Soma lignite for residential heating is important for the formation PM, SO2 and CO emissions. Also, traffic is playing an important role in the formation of VOC and NOx emissions. Share of expected annual ambient air emissions caused by natural gas consumption for industrial use and residential heating is less than other sources. Here, advantages of burning natural gas can be observed obviously.
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Recommendations • This study can be used for/in order to • Preperation of different scenarios, • Making future projections, • Investigte the relationship between pollution distribution and • land use data, • Investigate the seosonal variation, • Uncertainty analysis of the emission inventory, • Determination of some air quality parameters by using convenient • models with inventory results, • for example, determination of the ambient air concentration of a pollutant • Compare inventory results and measurement data.