FORUM-AE Workshop 1 Heathrow Airport Particulate Measurements 10th January 2014

Transcription

1 FORUM-AE Workshop 1 Heathrow Airport Particulate Measurements 10th January 2014 David Vowles Air Quality and Noise Policy Manager

2 Introduction Brief overview of Heathrow Continuous particle measurements PM 10 and PM 2.5 Additional Particulate measurements and projects Ultrafine Particles Sensor Network Project (with University of Cambridge)

3 Brief overview of Heathrow A single grass runway was built in 1930 Developed into RAF Heston in 1944 First passenger flight was 1 January 1946 to Buenos Aires UK s only hub airport - located in west London Covers area of 12.3km 2 Cap of 480,000 ATMs a year Approximately 1,290 ATMs per day 70 million passengers a year Approximately 191,200 a day 1.46 million tonnes cargo a year Only UK airport within an AQMA (for NO 2 )

4 Continuous particle measurements PM10 and PM2.5

5 Heathrow has one of the most extensive air quality monitoring regimes in Europe Heathrow operates 4 sites (highlighted) Monitoring on-airport has occurred since 1993 (LHR2) important for modelling, but an area where no people live Local authorities and the government operate the remainder Heathrow has an Air Quality Strategy in place to reduce airport-related emissions

6 Heathrow has the most extensive set of air quality monitoring in the local area measuring fine particles (PM 2.5 ) Pollutants measured Monitoring site Owner Site type NO NO 2 PM 10 PM 2.5 SO 2 O 3 LHR2 HAL Airport x x x x Harlington HAL Background x x x x x Green Gates HAL Urban x x x x background Oaks Road HAL Urban x x x x background Harmondsworth LB Hillingdon Background x x x Sipson LB Hillingdon Urban x x background Oxford Avenue LB Hillingdon Roadside x x x Hayes LB Hillingdon Roadside x x x Cranford LB Hounslow Suburban x x x x x Hatton Cross LB Hounslow Roadside x x x Heathrow is committed to capturing data no-one else has committed to London Hillingdon Defra Suburban x x x Slough Colnbrook Slough Borough Council Urban background x x x

7 Heathrow uses TEOMs to measure particles LHR2 site TEOM tapered element oscillating microbalance PM 10 - TEOM at LHR2, Green Gates and Oaks Road. FDMS TEOM (a modified form of TEOM which measures both volatile and non-volatile fractions) at Harlington. PM TEOM at LHR2, Green Gates and Oaks Road. FDMS TEOM at Harlington. (FDMS - Filter Dynamics Measurement System) Inlet for PM 10 or PM 2.5

8 Data collection and QA/QC is to national standards EU Directive on Ambient Air Quality (2008/50/EC) sets limit values for a range of pollutants UK Government has produced AQ objectives for England and Wales (must be at least as stringent as the EU limit values). Audit calibration procedures are UKAS accredited to ISO (documented in Ricardo-AEA s AURN QA/QC manual). AQ measurements are reviewed by Ricardo-AEA: Daily - results are compared with national monitoring stations Quarterly - to check for any spurious values and to apply the best daily zero and sensitivity factors 6-monthly - intercalibration and audit. Air intakes are cleaned and all aspects of site infrastructure are checked. Annually to incorporate information from the 6-monthly intercalibration audits to fully validate and finalise data

9 VCM correction for TEOM PM 10 Data TEOM monitors heat the sample inlet to 50 C to prevent condensation on the filter. This elevated temperature can result in the loss of volatile and semi-volatile components of PM 10, such as ammonium nitrate. King s College London (KCL) has developed a Volatile Correction Model, which allows TEOM PM 10 data to be corrected for the volatile components lost as a result of the TEOM s heated inlet, available at It uses data from nearby TEOM-FDMS particulate analysers, which measure the volatile and non-volatile components of the PM 10. The volatile component (which typically does not vary much over a large region), can be added to the TEOM measurement. KCL state that the resulting corrected measurements have been demonstrated as equivalent to the gravimetric reference equivalent. HAL uses this corrected PM 10 data. No requirement to correct PM 2.5 data measured using the TEOM.

10 Annual average gravimetric PM 10 measurements around Heathrow Airport

11 Trends in daily average PM 10 concentrations

12 Annual average gravimetric PM 2.5 measurements around Heathrow Airport FDMS monitor

13 Particulate monitoring - conclusions PM 10 and PM 2.5 concentrations meet EU limit values in the vicinity of the airport. All AQ measurements are made to national standards and are comparable to EU limit values Key emission sources aircraft, airside vehicles, landside vehicles and fixed boiler plant Heathrow s Air Quality Strategy is aimed at reducing airportrelated NO X emissions to help cut air pollution below EU limit values Many AQ Strategy actions will also reduce emissions of particles. The data does not enable us to carry out source apportionment Heathrow is keeping under review development in the impact of particles to inform future policies.

14 Ultrafine Particles

15 UFP monitoring at LHR - Friday 4th May 2012 TSI Model 3010 Condensation Particle Counter measures particle diameter range from 7nm to approximately 3 μm. On entering the CPC, particles pass through a saturator where the working fluid (butan-1-ol) evaporates into the gas stream to supersaturate it. The vapour condenses onto the particles to form droplets larger in diameter than the original particles. They pass through a laser and light scattered by the droplets is collected and focused onto a photodetector. The photo-detector converts the light signal to an electrical pulse that is recorded as a particle count.

16 Ultrafine particles - Data from Heathrow Airport -T5 Pushback GPU Arrival

17 T5 entire sampling period comparisons with PM fractions

18 UFP monitoring conclusions Pattern of particle number measured at Heathrow mirrored those taken at other airports (e.g. Copenhagen) Peak particle counts correlated with activity from nearby engines (e.g. auxiliary power unit, diesel GSE, aircraft engines) No clear relationship between peaks in UFP and in PM 10 and PM 2.5 concentrations The European Committee for Standardisation (CEN) is developing standards for the measurement of ultra-fine particles. At present, there are no agreed standard methods, nor have limit values or target values been agreed by the European Commission for exposure in ambient air. Heathrow will maintain a dialogue with other leading airports to compare findings on policies to reduce emissions of UFP (e.g. use of electric, hydrogen and other low/zero emission technologies)

19 SNAQ Sensor Network Project (with University of Cambridge)

20 SNAQ high density sensor network system at Heathrow Airport ( ) Objectives: Electro-chemical sensor network system for a range of air quality metrics in and around Heathrow airport. Novel software tools for network calibration, analysis and datamining, visualisation and interpretation. Evaluation against emissions inventories and dispersion models. Source attribution outputs for London Heathrow (area). Creation of a data set including NO, NO 2, CO, CO 2, SO 2, O 3, VOCs and size-speciated PM for science and policy studies. Optimising sensor network design for different environments. Funded by NERC

21 SNAQ sensor installed at Oaks Road monitoring site Cambridge sensor

22 Inner workings of a SNAQ sensor

23 Thirty three monitors were installed in 2012 and 2013

24 Attributing sources: sensor to the west of southern runway (27L) Particle number polar bivariate plots

25 High density sensor monitoring conclusions Ability to have a small-scale network of monitors Easier to locate than conventional monitors Ability to finger-print specific emissions sources and operations More data available for emission inventories? Ability to attribute emissions sources?

26 Conclusions Concentrations of conventional particles meet EU limit values around the airport Heathrow s AQ Strategy will help further reduce emissions of particles Impact of UFP is a developing area and one Heathrow will keep under review Installing a network of simpler monitors may give us a powerful management tool Heathrow will continue to carry out AQ monitoring and trial new techniques From current data, we can not assign source apportionment of any sources at pollution monitoring sites like we can with NO 2. I am looking into new ways to provide this information

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28 Annual average NO 2 concentrations measured around Heathrow Airport from 1995

29 Calculated source apportionment of NO X concentrations and measured NO 2 Hillingdon NO 2 Green Gates Sipson Oxford Ave Above limit value LHR2 Cranford Below limit value Oaks Road Hatton Cross Key: monitoring sites exceeds EU limit value close meets to EU EU limit limit value value meets EU limit value Reproduced from Ordnance Survey digital map data Crown copyright All rights reserved. Key: source apportionment Aircraft Auxiliary Power Units Airside Vehicles Other Airport Airport-related Road Traffic Other Road Traffic Background