Breckland Crematorium - Chimney Height Calculation
Breckland Crematorium Norwich Road Scoulton Norfolk NR9 4NR
Chimney Height Calculation Supporting information document February 2019
ehrc
Environmental Health Resource Centre Limited, 41 Elsiedene Road, London N21 2RN
eMail:
[email protected]
iPhone: 07802 349 581
eFax: 0871 66 11 321
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Contents: 1.0
Introduction
3
2.0
Input data
4
2.1
Cremation equipment
4
2.2
Emissions data
5
2.3
Local environmental data
7
2.4
Building information
8
3.0
Chimney height
8
Resources Appendices Appendix 1: Air quality maps Appendix 2: Site plan Appendix 2: Chimney height calculations
ehrc Breckland Crematorium - Chimney Height Calculation
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1.0
Introduction
ehrc were engaged to undertake a chimney height calculation for the proposed Breckland Crematorium. Breckland Crematorium will be a new crematorium housing two FTIII cremators. Exhaust gasses will pass though one abatement plant and process chimney. The purpose of this report is to determine the chimney height for the proposed installation. The methodology used in to calculate chimney height this assessment is the HMIP Technical Guidance Note D1 “Guidelines on Discharge Stack Heights for Polluting Emissions”, which takes into account a number of factors, including:
Stack diameter Emission release rates at reference conditions Emissions volume flow and efflux e fflux velocity and temperature at stack conditions The effect of nearby buildings Local background air quality data Guideline concentrations for protecting the environment
The D1 assessment is widely accepted by Regulators for the calculation of chimney heights for Crematoria. Surrogate data from other crematoria operating identical equipment will be used in this assessment because the proposed installation is not yet operational.
ehrc Breckland Crematorium - Chimney Height Calculation
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2.0
Input data
2.1
Cremation equipment
Perth Crematorium opening in 2018 and operates two FTIII cremators via single abatement plant is likely to be the influencing factor on emissions. The following data was obtained from the commissioning test report undertaken in June 2018 Perth Crematorium average of all runs: Parameter
Units
Stack inside diameter (all)
0.35
m
Exhaust gas flow rate (actual)
4514
m /hr
Exhaust gas flow rate (reference)
1799
m /hr
144 (417)
°C (°K)
Emission temperature Efflux velocity
8.6
3
3
m/s
Perth Crematorium Run H1: Parameter
Units 3
Exhaust gas flow rate (actual)
4514
m /hr
Exhaust gas flow rate (reference)
1799
m /hr
144 (417) 8.6
°C (°K) m/s
Emission temperature Efflux velocity
3
Perth Crematorium Run H2: Parameter
Units 3
Exhaust gas flow rate (actual)
4514
m /hr
Exhaust gas flow rate (reference)
1799
m /hr
144 (417)
°C (°K)
Emission temperature Efflux velocity
8.6
3
m/s
Perth Crematorium Run Hg1: Parameter
Units
Exhaust gas flow rate (actual) Exhaust gas flow rate (reference) Emission temperature Efflux velocity
3
4514
m /hr
1799 144 (417)
m3/hr °C (°K)
8.6
m/s
Perth Crematorium Run Hg2: Parameter
Units 3
Exhaust gas flow rate (actual)
4514
m /hr
Exhaust gas flow rate (reference)
1799
m /hr
144 (417) 8.6
°C (°K) m/s
Emission temperature Efflux velocity
ehrc Breckland Crematorium - Chimney Height Calculation
3
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Perth Crematorium Run D&F: Parameter
Units 3
Exhaust gas flow rate (actual)
4514
m /hr
Exhaust gas flow rate (reference)
1799
m /hr
144 (417)
°C (°K)
Emission temperature Efflux velocity
8.6
3
m/s
The full emissions test report used in this assessment is available as Appendix 2 to the permit application.
2.2
Emissions data
Crematoria are regulated under Environmental Permits, which require specific emission limits to be met. The emission limits for England, Scotland and Wales are well established in Process Guidance Note PG5/2(12) September 2012 as Best Available Techniques Emission Limits. Used in conjunction with the exhaust gas flow at reference conditions from the each Crematorium report, the maximum allowable emission rates in g/sec from the proposed crematorium can be calculated as follows: (Gas flowREF x 3600) x Emission Limit / 1000 = Emission ra rate te g/sec As can be seen from the emissions report, actual emissions from crematoria are much lower (better) than the permitted emission limits, but worst case emission limits are used in this assessment. Emission rates from the proposed chimney as used in the D1 assessment are as follows: Perth Crematorium average of all runs: Emission limit 3 (mg/m )
Exhaust gas flow rate (reference) 3 Nm /sec
Max mass emission rate (g/sec)
Particulate Matter
20.00
0.73
0.014692
Hydrogen Chloride Mercury
30.00 0.05
0.73 0.73
0.022038 0.000037
VOC
20.00
0.73
0.014692
Carbon Monoxide
100.00
0.73
0.073461
Emission limit 3 (mg/m )
Exhaust gas flow rate (reference) 3 Nm /sec
Max mass emission rate (g/sec)
Particulate Matter
20.00
0.76
0.015256
Hydrogen Chloride Mercury
30.00 0.05
0.76 0.76
0.022883 0.000038
VOC Carbon Monoxide
20.00 100.00
0.76 0.76
0.015256 0.076278
Parameter
Perth Crematorium Run H1:
Parameter
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Perth Crematorium Run H2: Emission limit 3 (mg/m )
Exhaust gas flow rate (reference) 3 Nm /sec
Max mass emission rate (g/sec)
Particulate Matter
20.00
0.72
0.014372
Hydrogen Chloride Mercury
30.00 0.05
0.72 0.72
0.021558 0.000036
VOC
20.00
0.72
0.014372
Carbon Monoxide
100.00
0.72
0.071861
Emission limit 3 (mg/m )
Exhaust gas flow rate (reference) 3 Nm /sec
Max mass emission rate (g/sec)
Particulate Matter
20.00
0.60
0.012039
Hydrogen Chloride
30.00
0.60
0.018058
Mercury
0.05
0.60
0.000030
VOC
20.00
0.60
0.012039
Carbon Monoxide
100.00
0.60
0.060194
Emission limit 3 (mg/m )
Exhaust gas flow rate (reference) 3 Nm /sec
Max mass emission rate (g/sec)
Particulate Matter
20.00
0.83
0.016656
Hydrogen Chloride
30.00
0.83
0.024983
Mercury VOC
0.05 20.00
0.83 0.83
0.000042 0.016656
Carbon Monoxide
100.00
0.83
0.083278
Emission limit 3 (mg/m )
Exhaust gas flow rate (reference) 3 Nm /sec
Max mass emission rate (g/sec)
Particulate Matter Hydrogen Chloride
20.00 30.00
0.76 0.76
0.015139 0.022708
Mercury VOC
0.05 20.00
0.76 0.76
0.000038 0.015139
Carbon Monoxide
100.00
0.76
0.075694
Parameter
Perth Crematorium Run Hg1:
Parameter
Perth Crematorium Run Hg2:
Parameter
Perth Crematorium Run D&F: Parameter
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2.3
Local environmental data
In addition to emissions and technical data, the D1 model uses Guideline concentration (Gd) data and Background concentration (Bc) data in the determination of chimney height. It is noted that Gd and Bc data in the D1 Document are out of date, and this section confirms that original D1 data has not been used in this assessment. For Gd, current in the D1the model is asstatutory follows: short-term Air Quality objectives have been used, and Gd data used Guideline Concentrations:
3
mg/m
Notes 3
Particulate Matter
0.05
50µg/m Air Quality objective (.gov.uk)
Hydrogen Chloride
0.750
750µg/m Hourly limit (.gov.uk)
Mercury
0.0075
7.5µg/m Hourly limit (.gov.uk)
VOC
0.195
195µg/m Hourly limit as Benzene (.gov.uk)
Carbon Monoxide
10.0
10mg/m Air Quality objective (.gov.uk)
3
3
3
3
For Background concentration (Bc), data was derived as follows: defra UK ambient air quality map for background air quality (where background data has been modelled for each UK kilometre grid square into a range of pollution concentrations) which is the resource generally used for D1 calculation, and Air Pollution in the UK 2015, (defra)
Bc data used in the D1 model is as follows: Background Concentrations: Particulate Matter Hydrogen Chloride
3
mg/m 0.017 0.00
Notes 3
13-17µg/m – UK Ambient Air Quality Interactive Map. Assumed zero. 3
Mercury
0.000003
3ng/m - Air Pollution in the UK 2015.
VOC (as if benzene)
0.00005
