Air quality dispersion modelling of wood smoke emissions in residential areas in Sweden

Transcription

1 Air quality dispersion modelling of wood smoke emissions in residential areas in Sweden Gunnar Omstedt 1, Christer Johansson 2 and Lars Gidhagen 1 1 Swedish Meteorological and Hydrological Institute, Norrköping, Sweden 2 The Institute of Applied Environment Research, Stockholm,Sweden Introduction Experimental sites Measurements Models Results Conclusions 7/9/24 1

2 The goal is to describe how the use of bio-mass for energy production effects: Emission (from units<1 MW) Air Quality Health To describe the effects the use and development of new technology will have on emissions in the future Focus on airborne particles Bio-mass-Health-Environment (BHM) Introduction Lycksele # Växjö 7/9/24 2 l #

3 Lycksele Experimental sites Växjö 7/9/24 3

4 M Residential wood boilers and stoves and monitoring stations in Lycksele/Sweden 136 old boilers 511 new boilers and stoves Fo M Airport C N Emission factors Particles mg/mj Modern boilers with heat storage tank.22 Old-type boilers with heat storage tank.89 Old-type boilers without heat storage tank 2.19 Stoves.11 Fireplace.11 Traffic exhaused Thermal plant (bio) Small scale oil Offroad mashines Yearly PM emission in Lycksele: 66 ton/year Snowcats Old wood boilers 7/9/24 4 New wood boilers and stoves

5 Ions (filter, IC) Particelmass (TEOM) (PM1 / PM2.5) Sot Hygroscopic properties (TDMA) Particle size distributions (DMPS) Composition (SAM) (filter fine-, coarse fraction, PIXE) Chemical composition (Hi-Vol PM1) Measurments Particles mass, number,size distribution and chemical composition Gases NOx, CO, SO2, VOC 7/9/24 5

6 Temperatur ( C ) PM2.5 (µg/m 3 ) Dec 28-Dec 11-Jan 25-Jan 8-Feb 22-Feb 8-Mar Forsdala Norrmalm town Centre Vindeln 14-Dec 28-Dec 11-Jan 25-Jan 8-Feb 22-Feb 8-Mar FORSDALA NORRMALM TOWN CENTRE VINDELN Group Group Measurments Temp < -1 C Temp > -1 C 7/9/24 6

7 Change in mean wind direction from hour-to-hour (degrees) Wind speed (m/s) Meteorological measurements Std V-rik (grader) Wind rose Lycksele Tannen Period: Wind Sonic max (.5/U,17) Vindhastighet (m/s) number of hours Stable conditions, define as L<2, for about 6% /9/24 7

8 Models Gaussian models: Airviro and Dispersion (partly based on the Danish OML model) Meteorological inputs: local measurements Computational Fluid Dynamic model: StarCD Meteorological inputs: from meteorological model (HIRLAM) 7/9/24 8

9 PM2.5 Forsdala (µg/m 3 ) Results Model Dispersion (µg/m 3 ) when T < -1 C Model Dispersion (µg/m 3 ) when T<-1 C Dispersion Airviro PM2.5 Norrmalm (µg/m 3 ) Model Dispersion (µg/m 3 ) when T<-1 C PM2.5 Town Centre (µg/m 3 ) Model Airviro (µg/m 3 ) when T < -1 C PM1 Forsdala (µg/m 3 ) Model Airviro (µg/m 3 ) when T<-1 C PM2.5 Norrmalm (µg/m 3 ) Model Airviro (µg/m 3 ) when T<-1 C PM2.5 Town Centre (µg/m 3 ) when T< -1 C 7/9/24 9

10 Dispersion Airviro Modell (Dispersion) (µg/m 3 ) då T > -1 grader PM2.5 (µg/m 3 ) Forsdala-Vindeln Modell (Airviro) (µg/m 3 ) då T > -1 grader PM2.5 (µg/m 3 ) Norrmalm-Vindeln PM2.5 (µg/m 3 ) Forsdala-Vindeln Modell (Dispersion) (µg/m 3 ) då T>-1 grader Modell (Airviro) (µg/m 3 ) då T>-1 grader PM2.5 (µg/m 3 ) Centrum-Vindeln PM2.5 (µg/m 3 ) Norrmalm-Vindeln Modell (Dispersion) (µg/m 3 ) då T> -1 grader Modell (Airviro) (µg/m 3 ) då T> -1 grader PM2.5 (µg/m 3 ) Centrum-Vindeln when T> -1C 7/9/24 1

11 PM2.5 (µg/m 3 ) Strong Activity data for domestic woodburning 14-Dec 28-Dec 11-Jan 25-Jan 8-Feb 22-Feb 8-Mar Weak Forsdala Norrmalm town Centre Vindeln Emissions are dependent on ambient temperature and this relationship must be considered in order not to overestimate the emissions 7/9/24 11

12 PM2.5 µg/m 3 PM2.5 µg/m Forsdala 14-Dec 28-Dec 11-Jan 25-Jan 8-Feb 22-Feb 8-Mar year 21/22 town centre Number of data points= 63 r=.75 Average X=9.4 Average Y=8.3 Number of data points= 74 r=.69 Average X=4.8 Average Y= Dec 28-Dec 11-Jan 25-Jan 8-Feb 22-Feb 8-Mar year 21/22 PM2.5 µg/m Norrmalm Results 14-Dec 28-Dec 11-Jan 25-Jan 8-Feb 22-Feb 8-Mar year 21/22 Lycksele, Sweden modell measurments Number of data points= 61 r=.67 Average X=7.8 Average Y=9.1 7/9/24 12

13 Furuvik/ Lycksele PM1 µg/m 3 9-percentiles of daily mean Example of model calculations Forsdala/ Lycksele PM1 µg/m 3 98-percentiles of daily mean 7/9/24 13

14 CFD model High resolution, horizontal 5*5 m, vertical 2 layers below 6 m ( grid cells) Meteorolog inputs by the meteorological model HIRLAM22 7/9/24 14

15 PM1(µg/m 3 ) Teleborg Number of data points=83 r=.91 Average X=13.5 Average Y= PM1 (µg/m 3 ) background PM1 (µg/m 3 ) Växjö centre Results- Växjö Number of data points=84 r=.72 Average X=13.7 Average Y= PM1 (µg/m 3 ) background Strong correlation between measured PM1 in the town and in background air 7/9/24 15

16 The emission factors and their time variability are very critical parameters for the model assessment of the air quality and its relation to standards in areas with massive use of wood stoves. Environmental air quality standards for PM1 and evaluation thresholds (according to EU directives) were exceeded in rather different meteorological conditions in the two towns. For the northern town the main contribution was from local sources, mainly from biomass burning in old wood stoves, during strongly stable, light wind conditions. For the southern town the main contribution was long-range transport of air pollutants. Domestic wood burning is the main contributor to the particle emissions from bio-mass use, due to use of old technology. The major abatement strategy to reduce emissions in the future is the application of new technology. Conclusions 7/9/24 16

17 Typical traffic and wood burning distributions Results from Lycksele (cold < -1 C) Central site Residential (Forsdala) Traffic (car tunnel) Wood stove ( laboratory exp.) dn/dlogdp (cm- 3 ) 1.5E+6 9.E+5 7.5E+5 6.E+5 4.5E+5 1.5E+5.E+.E+ 1.E+ 1.E+1 1.E+2 1.E+3 particle diameter (nm) 1.4E+8 1.2E E E+7 6.E E+5 4.E+7 2.E+7 dn/dlogdp (cm -3 ) p a rticle d ia m e te r (n m ) 7/9/24 17

18 Typical traffic and wood burning distributions Results from Lycksele (cold < -1 C) dn/dlogdp (cm -3 ) Central site Residential (Forsdala) p article d iam e te r (n m ) /9/24 18

19 Activity data for domestic woodburning Forsdala Norrmalm Temperatur Centrum Temperatur 7/9/24 19 PM2.5 (µg/m 3 ) Forsdala-Vindeln PM2.5 (µg/m 3 ) Norrmalm-Vindeln Temperatur Lycksele Forsdala Centrum Norrmalm Temperature (C) PM2.5 (µg/m 3 ) Centrum-Vindeln Activity factor