Air pollution dispersion modelling application for license procedures

Transcription

1 Air pollution dispersion modelling application for license procedures Dipl. Ing. Helmut Lorentz Radebeul, Mohrenstraße Environmental Manager Day South East Europe - Sofia 1

2 Content Dispersion Modelling of air pollution Limited values Procedure Selecting type of model Sensitive parameter Dispersion Model AUSTAL2000 Dispersion Model PLUME Environmental Manager Day South East Europe - Sofia 2

3 Air Quality Directives Air Quality Framework Directive and Daughter Directives have been introduced to control levels of certain pollutants 1. Daughter Directive 1999/30/EC - nitrogen dioxide (NO 2 ) and oxides of nitrogen (NO x ) - sulphur dioxide (SO 2 ) - particulate matter (PM10), PM2.5 is in discussion - lead (PB) 2. Daughter Directive 2000/69/EC - carbon monoxide (CO) - benzene (C 6 H 6 ) 3. Daughter Directive 2002/3/EC - ozone (O 3 ) 4. Daughter Directive 2004/107/EC - arsenic, cadmium, mercury, nickel and polycyclic aromatic hydrocarbons 4. Daughter Directive 2008/50/EG - PM Environmental Manager Day South East Europe - Sofia 3

4 Diagram Modelling Air Pollution Emission (mass of pollutants emitted by sources, e.g. motor vehicles) Transmission (transport, dispersion and conversion of pollutants) Immission (air pollution concentration or deposition of pollutants) Environmental Manager Day South East Europe - Sofia 4

5 Air Quality Modeling Digitizing emission sources (industry, traffic etc.) Emission parameters (Emission factors, emission rates, time series) Topography Buildings Emission Model Wind Field Model Wind field Library Emissions Dispersion parameters Meteorological Data Dispersion Model (Wind direction, -velocity, Stability class) Concentrations Background Level Industry Domestic Heating Side Roads Complete Concentrations Contribution from long Distance Emission Sources Environmental Manager Day South East Europe - Sofia 5

6 ??? Reliable, relevant Wind input data??? And emission models? Environmental Manager Day South East Europe - Sofia 6

7 Spatial scales of hot spot - models represents where the highest concentrations occur to which the population is exposed Traffic Screening model PROKAS, prognostic MISKAM Industry AUSTAL2000, LASAT Urban Suburban Rural Eco system AUSTAL2000, LASAT LASAT, EURAD LASAT, EURAD Environmental Manager Day South East Europe - Sofia 7

8 Which Model? Structure of the investigation Area Windfield Model Dispesion Model plain, no significant Buildings, but complex Road Network not required complex Relief, difering Land Cover, no significant Buildings DIWIMO KALM LPRWND (LASAT) METRAS-PC LASAT AUSTAL2000 plain, significant Buildings complex Relief, difering Land Cover, significant Buildings MISKAM LPRWND (LASAT) Kombination von KALM und LPRWND (LASAT) bzw. MISKAM MISKAM PROKAS_B LASAT IMMIS Luft Street AUSTAL2000 LASAT Calculation of Concentrations Wind Tunnel Simulation complex sources and conditions of despersion SF - Tracergas and Field Experiment 6 DIWIMO, LPRWND: diagnostic Windfield Model KALM : Nocturnal Flow Model METRAS-PC : meso-scaled prognostic Model MISKAM : micro-scaled prognostic Model Environmental Manager Day South East Europe - Sofia 8

9 Factors influencing Modelling Traffic - Number of vehicles per h on the road Emission - Share of vehicle types Emission - Traffic situation Emission - Turbulence due to car velocity Air flow Industry /Domestic Heating sources - Mass Flow concentration Emission - Exhaust parameter Air flow Topography - Deep and narrow valleys - Nocturnal valley drainage flow Air flow Buildings - Density and height of buildings - Distance between buildings at the roadside - Street canyon width Air flow Background concentration Environmental Manager Day South East Europe - Sofia 9

10 Meteorological Data Meteorological data representative for the area of investigation or? Environmental Manager Day South East Europe - Sofia 10

11 Influence Topography Changing of wind direction and wind velocity e.g. area of Stuttgart Online Windfeldberechnung (calculation of wind fields) Based on point measurements calculation of wind fields every 30 minutes for the area Stuttgart Environmental Manager Day South East Europe - Sofia 11

12 Example Topography Field of immissions calculated with LASAT - influence of topography: polluted area extend into valleys without sources Environmental Manager Day South East Europe - Sofia 12

13 Nocturnal Drainage Flow (1) During nights with few clouds and slow wind velocities the air at the ground cools down and flows gravity driven because of their higher density following the slope of terrain. Nocturnal valley drainage flow Nocturnal drainage flow from elevated plains and valleys as well as accumulation of cold air at the gound (Baumgartner, 1963) Environmental Manager Day South East Europe - Sofia 13

14 Nocturnal Drainage Flow (2) Uhr Uhr Uhr Smoke following the drainage flow at the ground into the valley Environmental Manager Day South East Europe - Sofia 14

15 Example Nocturnal Drainage Flow Distribution of pollutants without nocturnal drainage flow Distribution of pollutants with nocturnal drainage flow Environmental Manager Day South East Europe - Sofia 15

16 Street Canyon Measurement Position Environmental Manager Day South East Europe - Sofia 16

17 Influence of Building on wind flow Example of wind tunnel experience Environmental Manager Day South East Europe - Sofia 17

18 Roof Air flow PALM Längsschnitt / Dach Symmetrieebene PALM: zeitliches Mittel t=4-8h z u x MISKAM Beide Modelle: Gebäudeumströmung PALM: Dachwirbel Strömung über Dach gekrümmt Nachlaufwirbel bis über Dachniveau MISKAM: kein Dachwirbel Strömung kaum gekrümmt Nachlaufwirbel bis auf Dachniveau Environmental Manager Day South East Europe - Sofia 18

19 Local concentration PM10 Local Hot Spots at Streets Industry Train Road Traffic Ships Domestic Heating Offroad Offroad Regional Background km Source: U. Hartmann Environmental Manager Day South East Europe - Sofia 19

20 Restrictions of GAUSS Model Wind- and Turbulence fields are homogeneous in space and time Flat, homogeneous terrain Constant source strength invalid by calm, low windspeed Statistic of Dispersion Classes Dispersion parameters by experiments Dispersion coefficients valid in the range approx. 100 m km Results: Annual Mean Value, 98% Percentile Environmental Manager Day South East Europe - Sofia 20

21 Influence of stack height on ambient air concentration Relative concentration Low emission height High emission height Distance from Source Environmental Manager Day South East Europe - Sofia 21

22 Previous Gauss Model Gauß Model (AUSTAL86) Without direction change! Environmental Manager Day South East Europe - Sofia 22

23 Calculation area c max < 50*Stack height 50*30m=1500m Environmental Manager Day South East Europe - Sofia 23

24 PLUME Developed 1996 during a project PHARE Dispersion calculation with Gaussian formula The PLUME software was developed with a graphical user interface and it was taken into account that the user can easily apply it. PLUME has an interface to meteorological data from the national weather service. Consider wind speed and direction, stability classes of the atmosphere (Pasquill), plume rise formula (Hanna, 1982), horizontal advection, vertical and cross-wind turbulence, diffusion and gravitational deposition Implements vertical wind profile for urban or rural conditions Environmental Manager Day South East Europe - Sofia 24

25 PLUME The state of the art of PLUME represents the dispersion modeling knowledge and technical software level of the end of the 1990s Do not consider horizontal heterogeneity of the meteorological fields regarding the local relief or nocturnal air flow, dry deposition the chemical transformations, e.g. NO/NO 2 conversion Do not consider changes of plume travel according to chronological changings of meteorological parameters during the dispersion process Cannot calculate time series for all hours of a year Environmental Manager Day South East Europe - Sofia 25

26 History of Dispersion model for industrial sources in Germany Until 2002 the Gaussian dispersion model TALBO 86 was established as official dispersion model for industrial sources. From 2002 Lagrangian dispersion model AUSTAL2000 is the official German Federal Environmental Agency air pollution dispersion model and meets the demands contained in appendix 3 of the German "Technical Instruction Clean Air" (TA Luft) Environmental Manager Day South East Europe - Sofia 26

27 AUSTAL 2000 AUSTAL2000 contains a 3-dimensional LaGrange particle model (according to the German guideline VDI 3945 sheet 3) allowing to calculate as well concentration time series as statistical concentration parameters (annual mean) AUSTAL2000 able to cope with complex terrain (mountains, hills; max slope 1:5) and also the effects of buildings AUSTAL2000 is able calculate concentrations and odour frequency AUSTAL2000 is able calculate dry and wed depositions Environmental Manager Day South East Europe - Sofia 27

28 Thank you for your attention Environmental Manager Day South East Europe - Sofia 28