1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationBS EN ISO 6145-9:2010Gas analysis Preparation of calibration gas mixtures using dynamic volumetric methodsPart 9: Saturation method (ISO 6145-9:2009)BS EN ISO 6145-9:2010 BRITISH
2、 STANDARDNational forewordThis British Standard is the UK implementation of EN ISO6145-9:2010. It is identical to ISO 6145-9:2009. It supersedes BS ISO6145-9:2009, which is withdrawn.The UK participation in its preparation was entrusted to TechnicalCommittee PTI/15, Natural Gas and Gas Analysis.A li
3、st of organizations represented on this committee can beobtained on request to its secretary.This publication does not purport to include all the necessaryprovisions of a contract. Users are responsible for its correctapplication. BSI 2011 ISBN 978 0 580 72206 6 ICS 71.040.40 Compliance with a Briti
4、sh Standard cannot confer immunity fromlegal obligations.This British Standard was published under the authority of theStandards Policy and Strategy Committee on 28 February 2011. Amendments issued since publicationDate T e x t a f f e c t e dEUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO
5、6145-9 December 2010 ICS 71.040.40 English Version Gas analysis - Preparation of calibration gas mixtures using dynamic volumetric methods - Part 9: Saturation method (ISO 6145-9:2009) Analyse des gaz - Prparation des mlanges de gaz pour talonnage laide de mthodes volumtriques dynamiques - Partie 9:
6、 Mthode par saturation (ISO 6145-9:2009) Gasanalyse - Herstellung von Kalibriergasgemischen mit Hilfe von dynamisch-volumetrischen Verfahren - Teil 9: Sttigungsverfahren (ISO 6145-9:2009) This European Standard was approved by CEN on 11 December 2010. CEN members are bound to comply with the CEN/CEN
7、ELEC 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 CEN-CENELEC Management Centre
8、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 CEN-CENELEC Management Centre has the same status as the of
9、ficial versions. CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, S
10、lovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Management Centre: Avenue Marnix 17, B-1000 Brussels 2010 CEN All rights of exploitation in any form and by any means reserved worldw
11、ide for CEN national Members. Ref. No. EN ISO 6145-9:2010: EBS EN ISO 6145-9:2010 EN ISO 6145-9:2010 (E) 3 Foreword The text of ISO 6145-9:2009 has been prepared by Technical Committee ISO/TC 158 “Analysis of gases” of the International Organization for Standardization (ISO) and has been taken over
12、as EN ISO 6145-9:2010. 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 June 2011, and conflicting national standards shall be withdrawn at the latest by June 2011. Attention is drawn to the possib
13、ility that some of the elements of this document may be the subject of patent rights. CEN and/or CENELEC shall not be held responsible for identifying any or all such patent rights. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are
14、 bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spa
15、in, Sweden, Switzerland and the United Kingdom. Endorsement notice The text of ISO 6145-9:2009 has been approved by CEN as a EN ISO 6145-9:2010 without any modification. BS EN ISO 6145-9:2010ISO 6145-9:2009(E) ISO 2009 All rights reserved iiiContents Page Foreword iv 1 Scope1 2 Normative references1
16、 3 Terms and definitions .1 4 Principle1 5 Equipment 2 5.1 Set up2 5.2 Gas preparation .2 5.3 Compatibility of the apparatus.2 5.4 Selection of the apparatus2 5.5 Pressure measurement.2 5.6 Temperature control3 5.7 Instrumentation .3 5.8 Purity.4 6 Procedure.4 6.1 Installation4 6.2 Operation of a di
17、rect system4 6.3 Operation of a closed circulation system.4 7 Uncertainty of measurement5 Annex A (normative) Overview of vapour pressure data for various substances.7 Annex B (informative) Examples of uncertainty estimations.11 Bibliography14 BS EN ISO 6145-9:2010ISO 6145-9:2009(E) iv ISO 2009 All
18、rights reservedForeword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subjec
19、t for which a technical committee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC)
20、 on all matters of electrotechnical standardization. International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2. The main task of technical committees is to prepare International Standards. Draft International Standards adopted by the technical committee
21、s are circulated to the member bodies for voting. Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be he
22、ld responsible for identifying any or all such patent rights. ISO 6145-9 was prepared by Technical Committee ISO/TC 158, Analysis of gases. This second edition cancels and replaces the first edition (ISO 6145-9:2001) and ISO 6145-9:2001/Cor 1:2002, which have been technically revised. As Annex B is
23、purely informative, and included as a guide to the methods of calculation of the volume fractions, the numerical examples which are presented in it have been carried forward verbatim from ISO 6145-9:2001 to this updated standard. Although some references have been updated in the present bibliography
24、 to the most recent editions, the tables in Annex A have also been reproduced verbatim and are based on data from the earlier editions of the relevant publications (References 3, 4 and 7 to 10 in the Bibliography). In the application of this updated standard, it is firmly recommended that the more r
25、ecent versions of the publications be consulted, even though it is anticipated that any amendments to the earlier versions will be minor ones. For example, the 15th edition of Reference 4 was published in 1999 and the 2nd edition of Reference 8 was published in 1984. ISO 6145-9 also cancels and repl
26、aces ISO 6147, which has the same subject. In comparison with ISO 6147, ISO 6145-9 gives more detailed information on the use of the apparatus and a clause on the uncertainty of measurement has been added. The estimated uncertainties in the calibration methods and techniques have now been combined i
27、n a square-root sum-of-squares manner to form the relative combined standard uncertainty. ISO 6145 consists of the following parts, under the general title Gas analysis Preparation of calibration gas mixtures using dynamic volumetric methods: Part 1: Methods of calibration Part 2: Volumetric pumps P
28、art 4: Continuous syringe injection method Part 5: Capillary calibration devices Part 6: Critical orifices Part 7: Thermal mass-flow controllers Part 8: Diffusion method BS EN ISO 6145-9:2010ISO 6145-9:2009(E) ISO 2009 All rights reserved v Part 9: Saturation method Part 10: Permeation method Part 1
29、1: Electrochemical generation ISO 6145-3, entitled Periodic injections into a flowing gas stream, has been withdrawn. BS EN ISO 6145-9:2010BS EN ISO 6145-9:2010INTERNATIONAL STANDARD ISO 6145-9:2009(E) ISO 2009 All rights reserved 1Gas analysis Preparation of calibration gas mixtures using dynamic v
30、olumetric methods Part 9: Saturation method 1 Scope This part of ISO 6145 is one of a series of International Standards dealing with various dynamic volumetric methods used for the preparation of calibration gas mixtures. This part specifies a method for continuous production of calibration gas mixt
31、ures containing one or more readily condensable components. A relative expanded uncertainty of measurement, U, obtained by multiplying the relative combined standard uncertainty by a coverage factor k = 2, of not greater than 1 %, can be obtained using this method. Unlike the methods presented in th
32、e other parts of ISO 6145, the method described in this part does not require accurate measurement of flow rates since flow rates do not appear in the equations for calculation of the volume fraction. Readily condensable gases and vapours commonly become adsorbed on surfaces, and it is therefore dif
33、ficult to prepare stable calibration gas mixtures of accurately known composition, containing such components, by means of static methods. In addition, these calibration gas mixtures cannot be maintained under a pressure near the saturation limit without the occurrence of condensation. The saturatio
34、n method can be employed to prepare mixtures of this type. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (in
35、cluding any amendments) applies. ISO 6143, Gas analysis Comparison methods for determining and checking the composition of calibration gas mixtures ISO 7504, Gas analysis Vocabulary ISO 16664, Gas analysis Handling of calibration gases and gas mixtures Guidelines 3 Terms and definitions For the purp
36、oses of this document, the terms and definitions given in ISO 7504 apply. 4 Principle The vapour pressure of a pure substance in equilibrium with its condensed phase depends on the temperature only. At pressures close to the prevailing barometric pressure, and in the absence of significant BS EN ISO
37、 6145-9:2010ISO 6145-9:2009(E) 2 ISO 2009 All rights reservedgas phase interactions, such as occur with hydrocarbon mixtures, the volume fraction of the constituent can be calculated from knowledge of the temperature and pressure of the system. If a complementary gas is simply brought into contact w
38、ith the condensed phase of a volatile component at a given temperature with no external agency, the equilibrium (saturation) condition is reached quite slowly. In order to accelerate the process, the complementary gas is passed through the condensed phase at an elevated temperature, T1, following wh
39、ich the gas mixture thus obtained is cooled to a lower temperature, T2, which is below the dew-point. To ensure that saturation is attained, the difference in temperature (T1 T2) should be at least 5 K. The volume fraction xof the constituent x is, to a good approximation, equal to the ratio of the
40、vapour pressure pxof the calibration component at temperature T2to the total pressure p of the gas mixture at the same temperature in the condenser: xxpp = (1) The value of the relevant partial pressure (vapour pressure) of the constituent at temperature T2can be found in tables or diagrams in Refer
41、ences 1 to 4 in the Bibliography. 5 Equipment 5.1 Set up An overview of the equipment that shall be used for producing calibration gas mixtures by the saturation method is shown in Figure 1. A continuous flow of complementary gas from the supply (item 1 in Figure 1) is passed firstly through a filte
42、r (item 2 in Figure 2) containing quartz fibre material to remove suspended particles. NOTE Items 11 and 12 in Figure 1 are required only when a recycling system of calibration gas is employed. The procedure specified in 5.2 to 5.8 shall be followed for the assembly and use of the equipment in order
43、 to minimize uncertainty in the volume fraction of the components. 5.2 Gas preparation Clean and dry the complementary gas before it is introduced into the saturator. 5.3 Compatibility of the apparatus In the apparatus, use components, particularly sample lines, constructed exclusively in materials
44、which are known to exhibit negligible interaction with the components of the calibration gas mixture. Avoid materials which may be permeable to the component gases and/or the gas mixture, or upon which adsorption could take place. If in doubt, the compatibility of sample lines shall be checked befor
45、e they are used for the preparation of the sample gas mixture. 5.4 Selection of the apparatus Use sample lines of which the cross-sectional areas are of sufficient magnitude to ensure that the pressure drop resulting from the resistance to flow remains negligibly small. 5.5 Pressure measurement Meas
46、ure the total pressure at the outlet of the pressure-equalizing vessel. BS EN ISO 6145-9:2010ISO 6145-9:2009(E) ISO 2009 All rights reserved 3Key 1 supply of complementary gas 2 filter for suspended particles 3 saturator 4 condenser, constructed of a material that is of adequate thermal conductivity
47、 (e.g. copper or stainless steel) 5 pressure-equalizing vessel with baffles 6 pressure gauge 7 constant-temperature control (T1) 8 constant-temperature control (T2) 9 condensate outlet 10 calibration-gas-mixture outlet 11 circulation system 12 circulation pump Figure 1 Schema of equipment for produc
48、ing calibration gas mixtures by the saturation method 5.6 Temperature control This shall comply with the specification for transfer of calibration gas mixtures in ISO 16664. Ensure that the temperature of the gas line is sufficiently higher than T2so as to prevent condensation; when necessary, a hea
49、ted connecting line shall be provided. 5.7 Instrumentation Use exclusively instruments of high accuracy for measurement: thermometers with an error of measurement less than 0,05 K, and pressure-measuring devices with an error of measurement less than 1 hPa 1mbar 1). 1) 1 bar = 105N/m2= 0,1 MPa BS EN ISO 6145-9:2010ISO 6145-9:2009(E) 4 ISO 2009 All rights reserved5.8 Purity Use exclusively components of purity W 99,99 %, because certain impurities, if present, affect the vapour pres
