SIST EN 14791:2005

Stationary source emissions - Determination of mass concentration of sulphur dioxide - Reference method

This European Standard describes a manual method for sampling and determining SO2 content in ducts and stacks emitting to the atmosphere by two analytical methods: Ion chromatography and Thorin method.
This European Standard is the Standard Reference Method (SRM) for periodic monitoring and for calibration or control of Automatic Measuring Systems (AMS) permanently installed on a stack, for regulatory purposes or other purposes. To be used as the SRM, the user shall demonstrate that the performance characteristics of the method are better than the performance criteria defined in this European Standard and that the overall uncertainty of the method is less than ± 20,0 % relative at the daily Emission Limit Value (ELV).
An Alternative Method to this SRM may be used provided that the user can demonstrate equivalence according to the Technical Specification CEN TS 14793, to the satisfaction of his national accreditation body or law.
This Standard Reference Method has been evaluated during field tests on waste incineration, co-incineration and large combustion installations. It has been validated for sampling periods of 30 min in the range of (0,5   2 000) mg/m3 SO2 for Ion Chromatography variant and 5 mg/m3 - 2 000 mg/m3 SO2 for Thorin method according to emission limit values laid down in the following Council Directives:
3   Council Directive 2001/80/EC on the limitation of emissions of certain pollutants into the air from large combustion plants;
3   Council Directive 2000/76/EC on waste incineration plants.
The limit values of EU Directives are expressed in mg SO2/m3, on dry basis and at the reference conditions of 273 K and 101,3 kPa.

Emissionen aus stationären Quellen - Bestimmung der Massenkonzentration von Schwefeldioxid - Referenzverfahren

Diese Europäische Norm legt ein manuelles Verfahren fest zur Probenahme und Bestimmung des SO2-Gehaltes in Abgaskanälen, die ins Freie emittiert werden. Es werden zwei analytische Verfahren beschrieben: die Ionenchromatographie und das Thorin-Verfahren.
Diese Europäische Norm ist das Standardreferenzverfahren (SRM) für die periodische Überwachung und für die Kalibrierung oder Überprüfung von automatischen Messsystemen (AMS), die aus gesetzgeberischen oder anderen Gründen permanent an einem Abgaskanal installiert sind. Damit dieses Verfahren als Standardreferenzverfahren angewandt werden kann, muss nachgewiesen werden, dass die Verfahrenskenngrößen besser sind als die in dieser Norm festgelegten Leistungskriterien und dass die Gesamtmessunsicherheit des Verfahrens kleiner ist als 20 %, bezogen auf den Tages-Emissionsgrenzwert (ELV).
Ein Alternativverfahren zu diesem Standardreferenzverfahren darf angewendet werden, wenn der Anwender vor der nationalen Akkreditierungsstelle oder dem Gesetz die Äquivalenz nach der Technischen Spezifikation CEN/TS 14793 nachweisen kann.
Dieses Standardreferenzverfahren wurde in Feldversuchen an Müllverbrennungsanlagen und Mitverbrennungsanlagen sowie an Großfeuerungsanlagen beurteilt. Es wurde mit Probenahmedauern von 30 min für SO2-Konzentrationen im Bereich von 0,5 mg/m3 bis 2 000 mg/m3 SO2 mit der ionenchromatographischen Variante  und von 5 mg/m3 bis 2 000 mg/m3 SO2 für das Thorin-Verfahren validiert, entsprechend den in den folgenden Richtlinien des Europäischen Rats festgelegten Emissionsgrenzwerten:
-   Richtlinie 2001/80/EG des Europäischen Parlaments und des Rates vom 23. Oktober 2001 zur Begrenzung von Schadstoffemissionen von Großfeuerungsanlagen in die Luft;

Emissions de sources fixes - Détermination de la concentration massique du dioxide de soufre - Méthode de référence

La présente Norme européenne décrit une méthode manuelle de prélevement et de détermination, par le biais de deux méthodes analytiques, de la quantité de SO2 présente dans les conduits et les cheminées a l’origine d’émissions atmosphériques : chromatographie d’échange d’ions et méthode au Thorin.
La présente Norme européenne est la méthode de référence normalisée (SRM) en matiere de surveillance périodique et d’étalonnage ou de contrôle des systemes automatiques de mesurage (AMS) installés a demeure sur une cheminée, a des fins réglementaires ou autres. Pour l’utiliser comme SRM, l’utilisateur doit démontrer que les caractéristiques de performance de la méthode sont meilleures que les criteres de performance définis dans la présente Norme européenne et que l’incertitude globale de la méthode est inférieure a ± 20,0 % au niveau de la valeur limite d’émission journaliere (VLE).
Il est possible d’employer une méthode différente de cette SRM a condition que l’utilisateur puisse démontrer son équivalence selon la spécification technique de la CEN TS 14793 et en accord avec son organisme d’accréditation national ou la loi.
La présente méthode de référence normalisée a été évaluée au cours d’essais sur site pratiqués sur les installations destinées a l’incinération des déchets, a la coincinération et sur des grandes installations de combustion. Elle a été validée pour des périodes de prélevement de 30 min, dans la gamme de (0,5 a 2 000) mg/m3 SO2 pour la chromatographie d’échange d’ions et de 5 mg/m3 a 2 000 mg/m3 SO2 pour la méthode au Thorin, conformément aux valeurs limites d’émission spécifiées dans les directives du Conseil suivantes :
-   la Directive 2001/80/CEE sur la limitation des émissions de certains polluants dans l’atmosphere en provenance des grandes installations de combustion ;
-   la Directive 2000/76/CEE sur l’incinération des déchets.

Emisije nepremičnih virov – Določevanje masne koncentracije žveplovega dioksida – Referenčna metoda

General Information

• Status: Withdrawn
• Publication Date: 30-Nov-2005
• Withdrawal Date: 06-Jun-2017
• ICS: 13.040.40 - Stationary source emissions
• Technical Committee: KAZ - Air quality
• Current Stage: 9900 - Withdrawal (Adopted Project)
• Start Date: 30-May-2017
• Due Date: 22-Jun-2017
• Completion Date: 07-Jun-2017
• Directive: 88/609/EEC - Limitation of emissions of certain pollutants into the air from large combustion plants
• Directive: 89/369/EEC - Prevention of air pollution from new municipal waste incineration plants
• Directive: 89/429/EEC - Reduction of air pollution from existing municipal waste incineration plants
• Directive: 94/67/EC - Incineration of hazardous waste
• Mandate: M/278 - Standardization mandate to CEN for manual reference methods for the calibration of automated measurement systems for sulphur dioxide (S02) and nitrogen oxides (NOx) emissions in stack
• Ref Project: EN 14791:2005 - Stationary source emissions - Determination of mass concentration of sulphur dioxide - Reference method

Relations

• Replaced By: SIST EN 14791:2017 - Stationary source emissions - Determination of mass concentration of sulphur oxides - Standard reference method
• Effective Date: 01-Jul-2017

Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN 14791:2005
01-december-2005
(PLVLMHQHSUHPLþQLKYLURY±'RORþHYDQMHPDVQHNRQFHQWUDFLMHåYHSORYHJD
GLRNVLGD±5HIHUHQþQDPHWRGD
Stationary source emissions - Determination of mass concentration of sulphur dioxide -
Reference method
Emissionen aus stationären Quellen - Bestimmung der Massenkonzentration von
Schwefeldioxid - Referenzverfahren
Emissions de sources fixes - Détermination de la concentration massique du dioxide de
soufre - Méthode de référence
Ta slovenski standard je istoveten z: EN 14791:2005
ICS:
13.040.40 (PLVLMHQHSUHPLþQLKYLURY Stationary source emissions
SIST EN 14791:2005 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN 14791:2005

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SIST EN 14791:2005
EUROPEAN STANDARD
EN 14791
NORME EUROPÉENNE
EUROPÄISCHE NORM
November 2005
ICS 13.040.40

English Version
Stationary source emissions - Determination of mass
concentration of sulphur dioxide - Reference method
Emissions de sources fixes - Détermination de la Emissionen aus stationären Quellen - Bestimmung der
concentration massique du dioxide de soufre - Méthode de Massenkonzentration von Schwefeldioxid -
référence Referenzverfahren
This European Standard was approved by CEN on 30 September 2005.
CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European
Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national
standards may be obtained on application to the Central Secretariat or to any CEN member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by translation
under the responsibility of a CEN member into its own language and notified to the Central Secretariat has the same status as the official
versions.
CEN members are the national standards bodies of Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France,
Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia,
Slovenia, Spain, Sweden, Switzerland and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: rue de Stassart, 36  B-1050 Brussels
© 2005 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 14791:2005: E
worldwide for CEN national Members.

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SIST EN 14791:2005
EN 14791:2005 (E)
Contents Page
Foreword .5
1 Scope .6
2 Normative references .6
3 Terms, definitions, symbols and abbreviations .6
3.1 Terms and definitions.6
3.2 Symbols.11
3.3 Abbreviations .12
4 Principle.13
4.1 General .13
4.2 Measuring principle .13
5 Reagents.13
5.1 General .13
5.2 Hydrogen peroxide .13
5.3 Water.13
5.4 Absorption solution, H O .13
2 2
5.5 Reagents for chromatographic analysis .14
5.5.1 Eluent solution .14
2−
-3
5.5.2 Standard sulphate stock solution, 10,4x10 mol/l SO .14
4
5.5.3 Regeneration solution for suppressor .14
5.6 Reagent for Thorin analysis.14
5.6.1 2-propanol [CH CH(OH)CH ].14
3 3
5.6.2 Barium perchlorate, standard volumetric solution, [Ba(CIO ) ] = 0,005 mol/l.14
4 2
5.6.3 Potassium hydroxide, standard volumetric solution, [KOH] = 0,1 mol/l.15
5.6.4 Perchloric acid, standard volumetric solution, [HClO ] = 0,1 mol/l.15
4
5.6.5 Thorin, {4-[2-arsonophenyl)-azo]-3-hydroxy-2,7 naphthalene-disulfonic acid disodium salt} 2
g/l solution.15
6 Sampling equipment.15
6.1 General .15
6.2 Sampling probe.15

6.3 Filter housing .16
6.4 Particle filter .16
6.5 Temperature controller.16
6.6 Absorbers.16
6.6.1 General .16
2

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SIST EN 14791:2005
EN 14791:2005 (E)
6.6.2 Test of absorption efficiency .17
6.7 Sampling pump .17
6.8 Gas volume meter.17
7 Sampling procedure .18
7.1 General requirements.18
7.2 Preparation and installation of equipment.18
7.2.1 Sampling location .18
7.2.2 Sampling point(s).18
7.2.3 Assembling the equipment .19
7.2.4 Heating of the sampling line .19
7.2.5 Leak test .19
7.3 Performing sampling .19
7.3.1 Introduction of the probe in the duct.19
7.3.2 Sampling.19
7.3.3 Rinsing of the sampling system and preparation of the samples.20
7.4 Measuring series.20
7.5 Field blank .20
7.6 Absorption efficiency .21
8 Analysis equipment .21
8.1 Ion chromatograph .21
8.2 Thorin method.22
8.2.1 General .22
8.2.2 Spectrophotometer (optional).22
8.2.3 Glass optical cuvette .22
9 Analytical procedure.22
9.1 General .22
9.2 Ion Chromatography method.22
9.2.1 General procedure .22
9.2.2 Interferences .23
9.2.3 Calibration .23
9.3 Thorin Method.24
9.3.1 Pre-treatment of sample solution before analysis for Thorin method.24
9.3.2 General procedure .24
9.3.3 Preparation of a chemical blank solution .25
9.3.4 Interferents .25
10 Determination of the characteristics of the method: sampling and analyse.26
10.1 General .26
10.2 Relevant performance characteristics of the method and performance criteria .26

10.2.1 General .26
3

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SIST EN 14791:2005
EN 14791:2005 (E)
10.2.2 Sampling procedure .26
10.2.3 Analyse procedure.27
10.3 Establishment of the uncertainty budget.28
11 Expression of results.29
12 Evaluation of the method in the field.31
13 Equivalence of Thorin and ion chromatography methods .31
13.1 General .31
13.2 Range.31
13.3 Matrix effect.31
13.4 Comparison of repeatability and trueness.31
14 Equivalence with an alternative method .31
15 Test report .32
Annex A (informative) Type of sampling equipment.33
Annex B (informative) Examples of absorbers.34
Annex C (informative) Example of assessment of compliance or reference method for SO with
2
requirements on emission measurements.35
Annex D (informative) Evaluation of the method .43
Annex E (informative) Test of equivalency of Thorin method and ion chromatography .50
Annex ZA (informative) Relationship with EU Directives .60
Bibliography.61
4

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SIST EN 14791:2005
EN 14791:2005 (E)
Foreword
This European Standard (EN 14791:2005) has been prepared by Technical Committee CEN/TC 264 “Air quality”,
the secretariat of which is held by DIN.
This European Standard shall be given the status of a national standard, either by publication of an identical text or
by endorsement, at the latest by May 2006, and conflicting national standards shall be withdrawn at the latest by
May 2006.
This European Standard has been prepared under a mandate given to CEN by the European Commission and the
European Free Trade Association, and supports essential requirements of EU Directive(s).
For relationship with EU Directive(s), see informative Annex ZA, which is an integral part of this European Standard.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following
countries are bound to implement this European Standard: Austria, Belgium, Cyprus, Czech Republic, Denmark,
Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta,
Netherlands, Norway, Poland, Portugal, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.
5

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SIST EN 14791:2005
EN 14791:2005 (E)
1 Scope
This European Standard describes a manual method for sampling and determining SO content in ducts and
2
stacks emitting to the atmosphere by two analytical methods: Ion chromatography and Thorin method.
This European Standard is the Standard Reference Method (SRM) for periodic monitoring and for calibration or
control of Automatic Measuring Systems (AMS) permanently installed on a stack, for regulatory purposes or other
purposes. To be used as the SRM, the user shall demonstrate that the performance characteristics of the method
are better than the performance criteria defined in this European Standard and that the overall uncertainty of the
method is less than ± 20,0 % relative at the daily Emission Limit Value (ELV).
An Alternative Method to this SRM may be used provided that the user can demonstrate equivalence according to
the Technical Specification CEN TS 14793, to the satisfaction of his national accreditation body or law.
This Standard Reference Method has been evaluated during field tests on waste incineration, co-incineration and
large combustion installations. It has been validated for sampling periods of 30 min in the range of
3 3 3
(0,5 to 2 000) mg/m SO for Ion Chromatography variant and 5 mg/m to 2 000 mg/m SO for Thorin method
2 2
according to emission limit values laid down in the following Council Directives:
 Council Directive 2001/80/EC on the limitation of emissions of certain pollutants into the air from large
combustion plants;
 Council Directive 2000/76/EC on waste incineration plants.
3
The limit values of EU Directives are expressed in mg SO /m , on dry basis and at the reference conditions of

2
273 K and 101,3 kPa.
2 Normative references
The following referenced documents are indispensable for the application of this European Standard. For dated
references, only the edition cited applies. For undated references, the latest edition of the referenced document
(including any amendments) applies.
ENV 13005, Guide to the expression of uncertainly in measurement.
EN 13284-1, Stationary source emissions — Determination of low range mass concentration of dust — Part 1:
Manual gravimetric method.
CEN/TS 14793, Stationary source emission — Intralaboratory validation procedure for an alternative method
compared to a reference method.
3 Terms, definitions, symbols and abbreviations
3.1 Terms and definitions
For the purposes of this European Standard, the following terms and definitions apply.
3.1.1
absorber
device in which sulphur oxide is absorbed into an absorption liquid
6

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SIST EN 14791:2005
EN 14791:2005 (E)
3.1.2
absorption efficiency (εε)
εε
ratio ε of quantity of the analyte q collected in the first absorber divided by the quantity of the analyte collected in
1
the first and the second absorber (q + q )
1 2
ε = q / (q + q )
1 1 2
3.1.3
analytical detection limit (L )
D
concentration value of the measurand below which there is at least 95 % level of confidence that the measured
value corresponds to a sample free of that measurand
3.1.4
automatic measuring system (AMS)
measuring system permanently installed on site for continuous monitoring of emissions
NOTE 1 An AM is a method which is traceable to a reference method.
NOTE 2 Apart from the analyser, an AMS includes facilities for taking samples (e.g. probe, sample gas lines, flow meters,
regulators, delivery pumps) and for sample conditioning (e.g.dust filter, moisture removal devices, converters, diluters). This
definition also includes testing and adjusting devices, that are required for regular functional checks.
3.1.5
calibration of an AMS
statistical relationship between values of the measurand indicated by the measuring system (AMS) and the
corresponding values given by the standard reference method (SRM) used during the same period of time and
giving a representative measurement on the same sampling plane
NOTE The result of calibration permits to establish the relationship between the values of the SRM and the AMS
(calibration function).
3.1.6
calibration of the SRM
set of operations that establish, under specified conditions, the relationship between values of quantities indicated
by a measuring instrument or measuring system, and the corresponding values realized by standard reference
methods implemented in the state of the art in order to provide representative results
[VIM]
3.1.7
chemical blank value
sulphate ion content of an unexposed sample of the absorption solution, plus reagents that are added to the
solution before analysis if necessary
3.1.8
emission limit value (ELV)
emission limit value according to EU Directives on the basis of 30 min, 1 h or 1 day
3.1.9
field blank
value determined by a specific procedure used to ensure that no significant contamination has occurred during all
steps of the measurement and to check that the operator can achieve a quantification level adapted to the task
7

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SIST EN 14791:2005
EN 14791:2005 (E)
3.1.10
influence quantity
quantity that is not the measurand but that affects the result of the measurement
[adapted VIM 2.7]
Examples
 ambient temperature;
 atmospheric pressure;
 presence of interfering gases in the flue gas matrix.
3.1.11
measurand
particular quantity subject to measurement
[VIM 2.6]
3.1.12
measurement series
several successive measurements carried out on the same sampling plane and at the same process operating
conditions
[EN 13284-1]
3.1.13
measuring system
complete set of measuring instruments and other equipment assembled to carry out specified measurements
[VIM 4.5]
3.1.14
performance characteristic
one of the quantities (described by values, tolerances, range, …) assigned to equipment in order to define its
performance
8

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SIST EN 14791:2005
EN 14791:2005 (E)
3.1.15
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 Repeatability conditions include:
 same measurement procedure;
 same laboratory;
 same sampling equipment, used under the same conditions;
 same location;
 repetition over a short period of time.
NOTE 2 Repeatability may be expressed quantitatively in terms of the dispersion characteristics of the results.
In this European Standard the repeatability is expressed as a value with a level of confidence of 95 %.
[VIM 3.6]
3.1.16
repeatability in the field
closeness of the agreement between the results of simultaneous measurements of the same measurand carried
out with two equipments under the same conditions of measurement
NOTE 1 These conditions include:
 same measurement procedure;
 two equipments, the performances of which are fulfilling the requirements of the reference 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 Repeatability may be expressed quantitatively in terms of the dispersion characteristics of the results.
In this European Standard the repeatability under field conditions is expressed as a value with a level of confidence
of 95 %.
9

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SIST EN 14791:2005
EN 14791:2005 (E)
3.1.17
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 These conditions are called field reproducibility conditions and include:
 same measurement procedure;
 several sets of equipment, the performance of which fulfils the requirements of the reference method, used under the same
conditions;
 same location;
 implemented by several laboratories.
NOTE 2 Reproducibility may be expressed quantitatively in terms of the dispersion characteristics of the results.
In this European Standard the reproducibility under field conditions is expressed as a value with a level of
confidence of 95 %.
3.1.18
sampling location
specific area close to the sampling plane where the measurement devices are set up
3.1.19
sampling plane
plane normal to the centreline of the duct at the sampling position
[EN 13284-1]
3.1.20
sampling point
specific position on a sampling plane at which a sample is extracted
[EN 13284-1]
3.1.21
standard reference method (SRM)
measurement method recognised by experts and taken as a reference by convention, which gives, or is presumed
to give, the accepted reference value of the concentration of the measurand (3.1.11) to be measured
3.1.22
uncertainty
parameter associated with the result of a measurement, that characterises the dispersion of the values that could
reasonably be attributed to the measurand
3.1.22.1
standard uncertainty u
uncertainty of the result of a measurement expressed as a standard deviation u
3.1.22.2
combined uncertainty u
c
standard uncertainty u attached to the measurement result calculated by combination of several standard
c
uncertainties according to GUM
10

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SIST EN 14791:2005
EN 14791:2005 (E)
3.1.22.3
expanded uncertainty U
quantity defining a level of confidence about the result of a measurement that may be expected to encompass a
specific fraction of the distribution of values that could reasonably be attributed to a measurand
U = k x u
NOTE In this European Standard, the expanded uncertainty is calculated with a coverage factor of k = 2, and with a level of
confidence of 95 %.
3.1.22.4
overall uncertainty U
c
expanded combined standard uncertainty attached to the measurement result calculated according to GUM
U = k x u

c c
3.1.23
uncertainty budget
calculation table combining all the sources of uncertainty according to EN ISO 14956 or ENV 13005 in order to
calculate the overall uncertainty of the method at a specified value
3.2 Symbols
C mass concentration of sulphur dioxide in the sample gas, in milligrams per cubic metre (of gas)
m
repeatability confidence interval, in milligrams per cubic metre
Cl
r
Cl reproducibility confidence interval, in milligrams per cubic metre
R
f equivalent mass of sulphur dioxide of 1 mm of titration solution (barium perchlorate standard
a
volumetric solution) used for titration in Thorin method, in milligrams per millilitre
f ratio of the volume of the pre-treated sample solution (sample absorption solution pre-treated
v
before analyse) to the volume of the aliquot taken for the titration in Thorin method
2
L limit of detection, in milligrams per litre of SO
4
D
2
L limit of quantification, in milligrams per litre of SO
4
Q
m weight of the sample solution (absorption solution used for sampling + rinsing solution), in grams
s
P absolute pressure at the gas volume meter, in kilopascals
m
P standard pressure: 101,3 kPa
std
P saturation vapour pressure of water at volume gas meter temperature, in kilopascals
sat (Tm)
q mass concentration of sulphate in sample absorption solution, in milligrams per litre (of solution)
s
q mass concentration of sulphate in chemical blank solution, in milligrams per litre (of solution)
cb
r repeatability, in milligrams per cubic metre or percentage
R reproducibility, in milligrams per cubic metre or percentage
11

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SIST EN 14791:2005
EN 14791:2005 (E)
R peak resolution S : volume of titration solution used for titration of sample absorption solution, in
s s
millilitre
S volume of titration solution used for titration of chemical blank solution, in millilitre
cb
S repeatability standard deviation, in milligrams per cubic metre or percentage
r
S reproducibility standard deviation, in milligrams per cubic metre or percentag
...