Stationary source emissions - Determination of the mass concentration of sulphur dioxide by instrumental techniques

This Technical Specification describes a method for sampling and determining the concentration of gaseous sulphur dioxide (SO2) emissions from stacks. This method is based on instrumental techniques. It is applicable to both periodic measurements and the calibration of automated measuring systems permanently installed on stacks, for regulatory or other purposes.

Emissionen aus stationären Quellen - Ermittlung der Massenkonzentration von Schwefeldioxid mit instrumentellen Verfahren

Diese Technische Spezifikation beschreibt ein Verfahren zur Probenahme und Bestimmung der Konzentration von gasförmigem Schwefeldioxid (SO2) in Emissionen aus Abgaskanälen. Dieses Verfahren liegt den Techniken instrumenteller Analytik zugrunde. Es ist anwendbar bei wiederkehrenden Messungen und bei der Kalibrierung von automatischen Messeinrichtungen (AMS), die aus gesetzgeberischen oder anderen Gründen stationär an einem Abgaskanal installiert sind.

Émissions de sources fixes - Mesurage des émissions de dioxyde de soufre par des techniques instrumentales

La présente Spécification technique décrit une méthode de prélèvement et de détermination de la concentration des émissions de dioxyde de soufre gazeux (SO2) des cheminées. Cette méthode s’appuie sur des techniques instrumentales. Elle est applicable tant aux mesurages périodiques qu’à l’étalonnage des systèmes de mesurage automatisés installés à demeure sur des cheminées, à des fins réglementaires ou autres.

Emisije nepremičnih virov - Določevanje masne koncentracije žveplovega dioksida z instrumentalnimi tehnikami

Ta tehnična specifikacija opisuje metodo vzorčenja in določevanja koncentracije emisij plinastega žveplovega dioksida (SO2) iz odvodnikov. Ta metoda temelji na instrumentalnih tehnikah. Uporablja se za redno spremljanje in kalibracijo avtomatskih merilnih sistemov, ki so trajno nameščeni na odvodnike, in sicer za regulativne ter druge namene.

General Information

Status
Published
Public Enquiry End Date
19-Sep-2016
Publication Date
11-Jun-2017
Technical Committee
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
30-May-2017
Due Date
04-Aug-2017
Completion Date
12-Jun-2017

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SLOVENSKI STANDARD
SIST-TS CEN/TS 17021:2017
01-julij-2017
(PLVLMHQHSUHPLþQLKYLURY'RORþHYDQMHPDVQHNRQFHQWUDFLMHåYHSORYHJDGLRNVLGD
]LQVWUXPHQWDOQLPLWHKQLNDPL
Stationary source emissions - Determination of the mass concentration of sulphur
dioxide by instrumental techniques
Emissionen aus stationären Quellen - Ermittlung der Massenkonzentration von
Schwefeldioxid mit instrumentellen Verfahren
Émissions de sources fixes - Mesurage des émissions de dioxyde de soufre par des
techniques instrumentales
Ta slovenski standard je istoveten z: CEN/TS 17021:2017
ICS:
13.040.40 (PLVLMHQHSUHPLþQLKYLURY Stationary source emissions
SIST-TS CEN/TS 17021:2017 en,fr,de

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST-TS CEN/TS 17021:2017
CEN/TS 17021
TECHNICAL SPECIFICATION
SPÉCIFICATION TECHNIQUE
January 2017
TECHNISCHE SPEZIFIKATION
ICS 13.040.40
English Version
Stationary source emissions - Determination of the mass
concentration of sulphur dioxide by instrumental
techniques

Émissions de sources fixes - Détermination de la Emissionen aus stationären Quellen - Ermittlung der

concentration massique en dioxyde de soufre par des Massenkonzentration von Schwefeldioxid mit

techniques instrumentales instrumentellen Verfahren

This Technical Specification (CEN/TS) was approved by CEN on 23 October 2016 for provisional application.

The period of validity of this CEN/TS is limited initially to three years. After two years the members of CEN will be requested to

submit their comments, particularly on the question whether the CEN/TS can be converted into a European Standard.

CEN members are required to announce the existence of this CEN/TS in the same way as for an EN and to make the CEN/TS

available promptly at national level in an appropriate form. It is permissible to keep conflicting national standards in force (in

parallel to the CEN/TS) until the final decision about the possible conversion of the CEN/TS into an EN is reached.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,

Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,

Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,

Turkey and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels

© 2017 CEN All rights of exploitation in any form and by any means reserved Ref. No. CEN/TS 17021:2017 E

worldwide for CEN national Members.
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Contents Page

European foreword ....................................................................................................................................................... 4

1 Scope .................................................................................................................................................................... 5

2 Normative references .................................................................................................................................... 5

3 Terms and definitions ................................................................................................................................... 5

4 Symbols and abbreviations ...................................................................................................................... 11

4.1 Symbols ............................................................................................................................................................ 11

4.2 Abbreviated terms ....................................................................................................................................... 12

5 Principle .......................................................................................................................................................... 12

5.1 General ............................................................................................................................................................. 12

5.2 Measuring principle .................................................................................................................................... 12

6 Description of the measuring system ................................................................................................... 13

6.1 General ............................................................................................................................................................. 13

6.2 Sampling and sample gas conditioning system ................................................................................. 14

6.3 Analyser equipment .................................................................................................................................... 16

7 Performance characteristics of the method ....................................................................................... 16

8 Suitability of the measuring system for the measurement task ................................................. 18

9 Field operation .............................................................................................................................................. 18

9.1 Measurement section and measurement plane ................................................................................ 18

9.2 Sampling strategy......................................................................................................................................... 19

9.3 Choice of the measuring system ............................................................................................................. 19

9.4 Setting of the measuring system on site .............................................................................................. 20

10 Ongoing quality control ............................................................................................................................. 22

10.1 Introduction ................................................................................................................................................... 22

10.2 Frequency of checks .................................................................................................................................... 22

11 Expression of results ................................................................................................................................... 23

12 Measurement report ................................................................................................................................... 23

Annex A (informative) Example of uncertainty estimation for the method and compliance

with required emissions measurement uncertainty ...................................................................... 24

A.1 General ............................................................................................................................................................. 24

A.2 Elements required for the uncertainty determinations ................................................................ 24

A.3 Example uncertainty budget .................................................................................................................... 27

A.4 Evaluation of compliance with a required measurement uncertainty ..................................... 32

Annex B (informative) Calculation of the uncertainty associated with a concentration

expressed under dry conditions and at an oxygen reference concentration ......................... 34

B.1 Uncertainty associated with a concentration expressed under dry conditions.................... 34

B.2 Uncertainty associated with a concentration expressed at a O reference

concentration ................................................................................................................................................ 36

Annex C (normative) Annual lack of fit test ..................................................................................................... 38

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C.1 Description of test procedure .................................................................................................................. 38

C.2 Establishment of the regression line ..................................................................................................... 38

C.3 Calculation of the residuals ....................................................................................................................... 39

C.4 Test requirements ........................................................................................................................................ 39

Annex D (informative) Annual check of conditioning system ................................................................... 40

D.1 General ............................................................................................................................................................. 40

D.2 Demonstration via proficiency testing scheme participation ...................................................... 40

D.3 Demonstration via direct user testing of conditioning system .................................................... 40

Annex E (informative) Procedure for correction of data from drift effect............................................ 42

Annex F (informative) Chemistry of SO aqueous solubility ...................................................................... 44

Bibliography ................................................................................................................................................................. 45

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European foreword

This document (CEN/TS 17021:2017) has been prepared by Technical Committee CEN/TC 264 “Air

quality”, the secretariat of which is held by DIN.

Attention is drawn to the possibility that some of the elements of this document may be the subject of

patent rights. CEN shall not be held responsible for identifying any or all such patent rights.

According to the CEN-CENELEC Internal Regulations, the national standards organisations of the

following countries are bound to announce this Technical Specification: Austria, Belgium, Bulgaria,

Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia,

France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta,

Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,

Turkey and the United Kingdom.
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1 Scope

This Technical Specification describes a method for sampling and determining the concentration of

gaseous sulphur dioxide (SO ) emissions from stacks. This method is based on instrumental techniques.

It is applicable to both periodic measurements and the calibration of automated measuring systems

permanently installed on stacks, for regulatory or other purposes.
2 Normative references

The following documents, in whole or in part, are normatively referenced in this document and are

indispensable for its application. For dated references, only the edition cited applies. For undated

references, the latest edition of the referenced document (including any amendments) applies.

EN 15259:2007, Air quality - Measurement of stationary source emissions - Requirements for

measurement sections and sites and for the measurement objective, plan and report

EN 14793:2016, Stationary source emission - Demonstration of equivalence of an alternative method with

a reference method

EN 15267-4, Air quality - Certification of automated measuring systems - Part 4: Performance criteria and

test procedures for automated measuring systems for periodic measurements of emissions from stationary

sources

EN ISO 14956:2002, Air quality - Evaluation of the suitability of a measurement procedure by comparison

with a required measurement uncertainty (ISO 14956:2002)

ISO/IEC Guide 98-3, Uncertainty of measurement — Part 3: Guide to the expression of uncertainty in

measurement (GUM:1995)
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
standard reference method
SRM
reference method prescribed by European or national legislation
[SOURCE: EN 15259:2007]
3.2
reference method

measurement method taken as a reference by convention, which gives the accepted reference value of

the measurand
NOTE 1 A reference method is fully described.
NOTE 2 A reference method can be a manual or an automated method.

NOTE 3 Alternative methods can be used if equivalence to the reference method has been demonstrated.

[SOURCE: EN 15259:2007]
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3.3
alternative method

measurement method which complies with the criteria given by this Technical Specification with

respect to the reference method

Note 1 to entry: An alternative method can consist of a simplification of the reference method.

[SOURCE: EN 14793:2017]
3.4
measuring system

set of one or more measuring instruments and often other devices, including any reagent and supply,

assembled and adapted to give information used to generate measured quantity values within specified

intervals for quantities of specified kinds
[SOURCE: JCGM 200:2012]
3.5
automated measuring system
AMS

entirety of all measuring instruments and additional devices for obtaining a result of measurement

Note 1 to entry: Apart from the actual measuring device (the analyser), an AMS includes facilities for taking

samples (e.g. probe, sample gas lines, flow meters and regulator, delivery pump) and for sample conditioning (e.g.

dust filter, pre-separator for interferents, cooler, converter). This definition also includes testing and adjusting

devices that are required for functional checks and, if applicable, for commissioning.

Note 2 to entry: The term “automated measuring system” (AMS) is typically used in Europe. The term

“continuous emission monitoring system” (CEMS) is also typically used in the UK and USA.

[SOURCE: EN 15267-4:2017]
3.6
portable automated measuring system
P-AMS

automated measuring system which is in a condition or application to be moved from one to another

measurement site to obtain measurement results for a short measurement period
Note 1 to entry: The measurement period is typically 8 h for a day.

Note 2 to entry: The P-AMS can be configured at the measurement site for the special application but can be

also set-up in a van or mobile container. The probe and the sample gas lines are installed often just before the

measurement task is started.
[SOURCE: EN 15267-4:2017]
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3.7
calibration

set of operations that establish, under specified conditions, the relationship between values of

quantities indicated by a measuring method or measuring system, and the corresponding values given

by the applicable reference

Note 1 to entry: In case of automated measuring system (AMS) permanently installed on a stack the applicable

reference is the standard reference method (SRM) used to establish the calibration function of the AMS.

Note 2 to entry: Calibration should not be confused with adjustment of a measuring system.

[SOURCE: EN 15058:2017]
3.8
adjustment

set of operations carried out on a measuring system so that it provides prescribed indications

corresponding to given values of a quantity to be measured

Note 1 to entry: The adjustment can be made directly on the instrument or using a suitable calculation

procedure.
[SOURCE: EN 15058:2017]
3.9
span gas

test gas used to adjust and check a specific point on the response line of the measuring system

Note 1 to entry: This concentration is often chosen around 80 % of the upper limit of the range

3.10
measurand
particular quantity subject to measurement
[SOURCE: EN 15259:2007]

Note 1 to entry: The measurand is a quantifiable property of the stack gas under test, for example mass

concentration of a measured component, temperature, velocity, mass flow, oxygen content and water vapour

content.
3.11
interference

negative or positive effect upon the response of the measuring system, due to a component of the

sample that is not the measurand
3.12
influence quantity

quantity that is not the measurand but that affects the result of the measurement

Note 1 to entry: Influence quantities are e.g. presence of interfering gases, ambient temperature, pressure of the

gas sample.
3.13
ambient temperature
temperature of the air around the measuring system
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3.14
emission limit value
ELV

limit value given in regulations such as EU Directives, ordinances, administrative regulations, permits,

licences, authorizations or consents

Note 1 to entry: ELV can be stated as concentration limits expressed as half-hourly, hourly and daily averaged

values, or mass flow limits expressed as hourly, daily, weekly, monthly or annually aggregated values.

3.15
measurement site

place on the waste gas duct in the area of the measurement plane(s) consisting of structures and

technical equipment, for example working platforms, measurement ports, energy supply

Note 1 to entry: Measurement site is also known as sampling site.
[SOURCE: EN 15259:2007]
3.16
measurement plane
plane normal to the centreline of the duct at the sampling position
Note 1 to entry: Measurement plane is also known as sampling plane.
[SOURCE: EN 15259:2007]
3.17
measurement port

opening in the waste gas duct along the measurement line, through which access to the waste gas is

gained
Note 1 to entry: Measurement port is also known as sampling port or access port.
[SOURCE: EN 15259:2007]
3.18
measurement line

line in the measurement plane along which the measurement points are located, bounded by the inner

duct wall
Note 1 to entry: Measurement line is also known as sampling line.
[SOURCE: EN 15259:2007]
3.19
measurement point

position in the measurement plane at which the sample stream is extracted or the measurement data

are obtained directly
Note 1 to entry: Measurement point is also known as sampling point.
[SOURCE: EN 15259:2007]
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3.20
performance characteristic

one of the quantities (described by values, tolerances, range) assigned to equipment in order to define

its performance
3.21
response time

duration between the instant when an input quantity value of a measuring instrument or measuring

system is subjected to an abrupt change between two specified constant quantity values and the instant

when a corresponding indication settles within specified limits around its final steady value

Note 1 to entry: By convention time taken for the output signal to pass from 0 % to 90 % of the final variation of

indication.
3.22
short-term zero drift

difference between two zero readings at the beginning and at the end of the measurement period

3.23
short-term span drift

difference between two span readings at the beginning and at the end of the measurement period

3.24
lack of fit

systematic deviation within the range of application between the measurement result obtained by

applying the calibration function to the observed response of the measuring system measuring test

gases and the corresponding accepted value of such test gases
Note 1 to entry: Lack of fit can be a function of the measurement result.

Note 2 to entry: The expression “lack of fit” is often replaced in everyday language by “linearity” or “deviation

from linearity”.
3.25
repeatability in the laboratory

closeness of the agreement between the results of successive measurements of the same measurand

carried out under the same conditions of measurement
Note 1 to entry: Repeatability conditions include:
— same measurement method;
— same laboratory;
— same measuring system, used under the same conditions;
— same location;
— repetition over a short period of time.

Note 2 to entry: Repeatability can be expressed quantitatively in terms of the dispersion characteristics of the

results.

Note 3 to entry: In this Technical Specification the repeatability is expressed as a value with a level of

confidence of 95 %.
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3.26
repeatability in the field

closeness of the agreement between the results of simultaneous measurements of the same measurand

carried out with two sets of equipment under the same conditions of measurement
Note 1 to entry: These conditions include:
— same measurement method;

— two sets of equipment, the performances of which are fulfilling the requirements of the measurement

method, used under the same conditions;
— same location;
— implemented by the same laboratory;

— typically calculated on short periods of time in order to avoid the effect of changes of influence parameters

(e.g. 30 min).

Note 2 to entry: Repeatability can be expressed quantitatively in terms of the dispersion characteristics of the

results.

Note 3 to entry: In this Technical Specification, the repeatability under field conditions is expressed as a value

with a level of confidence of 95 %.
3.27
reproducibility in the field

closeness of the agreement between the results of simultaneous measurements of the same measurand

carried out with several sets of equipment under the same conditions of measurement

Note 1 to entry: These conditions are called field reproducibility conditions and include:

— same measurement method;

— several sets of equipment, the performances of which are fulfilling the requirements of the measurement

method, used under the same conditions;
— same location;
— implemented by several laboratories.

Note 2 to entry: Reproducibility can be expressed quantitatively in terms of the dispersion characteristics of the

results.

Note 3 to entry: In this Technical Specification, the reproducibility under field conditions is expressed as a value

with a level of confidence of 95 %.
3.28
residence time in the measuring system

time period for the sampled gas to be transported from the inlet of the probe to the inlet of the

measurement cell
3.29
uncertainty

parameter associated with the result of a measurement that characterizes the dispersion of the values

that could reasonably be attributed to the measurand
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3.30
standard uncertainty
uncertainty of the result of a measurement expressed as a standard deviation
3.31
combined uncertainty

standard uncertainty attached to the measurement result calculated by combination of several standard

uncertainties according to the principles laid down in ISO/IEC Guide 98-3 (GUM)
3.32
expanded uncertainty

quantity defining an interval about the result of a measurement that may be expected to encompass a

large fraction of the distribution of values that could reasonably be attributed to the measurand

U ku× c

Note 1 to entry: In this European Technical Specification, the expanded uncertainty is calculated with a level of

confidence of 95 %.

Note 2 to entry: The expression overall uncertainty is sometimes used to express the expanded uncertainty.

3.33
uncertainty budget

calculation table combining all the sources of uncertainty according to EN ISO 14956 or

ISO/IEC Guide 98-3 in order to calculate the combined uncertainty of the method at a specified value

4 Symbols and abbreviations
4.1 Symbols
For the purposes of this document, the following symbols apply.

A(t ) (result given by the analyser after adjustment at t at span point – result given by the

0 0

analyser after adjustment at t at zero point) / (calibration gas concentration at span point

– calibration gas concentration at zero point)
B(t ) result given by the analyser after adjustment at t at zero point
0 0
C measured concentration
C measured concentration corrected for drift
corr

Drift(A) {[(result given by the analyser during the drift check at t at span point – result given by

end

the analyser during the drift check at t at zero point) / (calibration gas concentration at

end
span point – calibration gas concentration at zero point)] – A(t )} / (t – t )
0 end 0

Drift(B) (result given by the analyser during the drift check at t at zero point – result given by the

end
analyser after adjustment at t at zero point) / (t – t )
0 end 0
f volume fraction
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k coverage factor
M molar mass
mol
t time
t time of adjustment
t time of check for drift at the end of the measurement period
end
u standard uncertainty
u combined uncertainty
U expanded uncertainty
V molar volume
mol
4.2 Abbreviated terms
For the purposes of this document, the following abbreviated terms apply.
AM alternative method
AMS automated measuring system
P-AMS portable automated measuring system
PTFE polytetrafluoroethene
SRM standard reference method
5 Principle
5.1 General

This Technical Specification describes a method for sampling and determining SO emissions using an

instrumental technique. This Technical Specification does not prescribe a specific technique; however,

it does prescribe performance criteria in Clause 7 for the analyser and the associated sampling system

(the complete measuring system). The performance characteristics of the method shall meet these

performance criteria. This Technical Specification also specifies requirements and recommendations

for ongoing quality assurance and quality control in Clause 10.
5.2 Measuring principle

The measuring systems used for SO measurements shall be extractive and typically comprise of the

following parts:
— a sampling probe;
— a filter;
— a sample gas line;
— a conditioning system;
— an analytical instrument.
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There are a number of instrumental techniques available for the analyser, which can measure SO in

emissions. Examples include infrared (IR) absorption, ultraviolet (UV) absorption, UV fluorescence and

electrochemical cells. The complete sampling system and analytical system is known as a portable

automated measuring system (P-AMS).

The concentration of SO is measured as a volume concentration if the analyser is calibrated using a

volume concentration standard. The final results for reporting are expressed in milligrams per cubic

metre (mg/m ) and reported at standard conditions (see Clause 11).
6 Description of the measuring system
6.1 General

A sample is extracted from the emission source for the required period of time at a controlled flow rate.

A filter removes the dust in the sampled volume before the sample is conditioned (unless

configuration 4 is being used) and passed to the analyser.

Different sampling and conditioning configurations are available in order to avoid the water vapour

condensation in the measuring system.
Possible configurations are:

— Configuration 1: removal of water vapour by condensation using a cooling system;

— Configuration 2: removal of water vapour through elimination using a permeation drier;

— Configuration 3: dilution with dry, clean ambient air or nitrogen of the gas to be characterized;

— Configuration 4: maintaining a temperature of all parts of the sampling system up to the analyser.

It is important that all parts of the sampling equipment upstream of the analyser are made of materials

that do not react with or absorb SO .

All components coming into contact with the gas shall be maintained at a temperature of at least 160 °C.

For configuration 1 this only applies to components upstream of the conditioning unit. For

configuration 3 this only applies to components upstream of the point of dilution. Heating is not

required post the dilution point as it is a requirement to decrease the sample acid dew point to below

ambient temperature (see 6.2.4.2).

NOTE For configuration 2 it can be necessary to introduce pre-cooling apparatus before the permeation drier

to avoid temperatures of over 120 °C at the permeation tubes as this is likely to cause damage.

If there are droplets present in the stack gas it should be discussed with the local competent authority if

this method is appropriate.

The conditions and layout of the sampling equipment contribute to the combined uncertainty of the

measurement. In order to minimize this contribution this Technical Specification specifies performance

criteria for the sampling system given in Table 1.
Alternative conditioning systems exist and may be acceptable, pro
...

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