DIN EN ISO 6145-9-2011 Gas analysis - Preparation of calibration gas mixtures using dynamic volumetric methods - Part 9 Saturation method (ISO 6145-9 2009) German version EN ISO 61.pdf

1、March 2011 Translation by DIN-Sprachendienst.English price group 12No part of this translation may be reproduced without prior permission ofDIN Deutsches Institut fr Normung e. V., Berlin. Beuth Verlag GmbH, 10772 Berlin, Germany,has the exclusive right of sale for German Standards (DIN-Normen).ICS

2、71.040.40!$n:1“1752314www.din.deDDIN EN ISO 6145-9Gas analysis Preparation of calibration gas mixtures using dynamic volumetricmethods Part 9: Saturation method (ISO 6145-9:2009)English translation of DIN EN ISO 6145-9:2011-03Gasanalyse Herstellung von Kalibriergasgemischen mit Hilfe von dynamisch-v

3、olumetrischenVerfahren Teil 9: Sttigungsverfahren (ISO 6145-9:2009)Englische bersetzung von DIN EN ISO 6145-9:2011-03Analyse des gaz Prparation des mlanges de gaz pour talonnage laide de mthodes volumtriquesdynamiques Partie 9: Mthode par saturation (ISO 6145-9:2009)Traduction anglaise de DIN EN ISO

4、 6145-9:2011-03www.beuth.deDocument comprises pagesIn case of doubt, the German-language original shall be considered authoritative.2103.11 DIN EN ISO 6145-9:2011-03 2 A comma is used as the decimal marker. National foreword This standard has been prepared by Technical Committee ISO/TC 158 “Analysis

5、 of gases” (Secretariat: NEN, Netherlands) and has been taken over as EN ISO 6145-9:2010 by Technical Committee CEN/SS N21 “Gaseous fuels and combustible gas” (Secretariat: CCMC). The responsible German body involved in its preparation was the Normenausschuss Materialprfung (Materials Testing Standa

6、rds Committee), Working Committee NA 062-05-73 AA Gasanalyse und Gas-beschaffenheit. 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 Part 4

7、: Continuous injection method Part 5: Capillary calibration devices Part 6: Critical orifices Part 7: Thermal mass-flow controllers Part 8: Diffusion method Part 9: Saturation method Part 10: Permeation method Part 11: Electrochemical generation The DIN Standards corresponding to the International S

8、tandards referred to in this document are as follows: ISO 6143 DIN EN ISO 6143 ISO 6144 DIN EN ISO 6144 ISO 6145-1 DIN EN ISO 6145-1 ISO 6145-7 DIN EN ISO 6145-7 ISO 7504 DIN V 51897 ISO 16664 DIN EN ISO 16664 s ringeyDIN EN ISO 6145-9:2011-03 3 National Annex NA (informative) Bibliography DIN V 518

9、97, Gas analysis Definitions and explanations DIN EN ISO 6143, Gas analysis Comparison methods for determining and checking the composition of calibration gas mixtures DIN EN ISO 6144, Gas analysis Preparation of calibration gas mixtures Static volumetric method DIN EN ISO 6145-1, Gas analysis Prepa

10、ration of calibration gas mixtures using dynamic volumetric methods Part 1: Methods of calibration DIN EN ISO 6145-7, Gas analysis Preparation of calibration gas mixtures using dynamic volumetric methods Part 7: Thermal mass-flow controllers DIN EN ISO 16664, Gas analysis Handling of calibration gas

11、es and gas mixtures Guidelines DIN EN ISO 6145-9:2011-03 4 This page is intentionally blank EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 6145-9 December 2010 ICS 71.040.40 English Version Gas analysis - Preparation of calibration gas mixtures using dynamic volumetric methods - Part 9: Sa

12、turation method (ISO 6145-9:2009) Analyse des gaz - Prparation des mlanges de gaz pour talonnage laide de mthodes volumtriques dynamiques - Partie 9: Mthode par saturation (ISO 6145-9:2009) Gasanalyse - Herstellung von Kalibriergasgemischen mit Hilfe von dynamisch-volumetrischen Verfahren - Teil 9:

13、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/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Up

14、-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN member. This European Standard exists in three official versions (English, French, German). A version in any other language made by trans

15、lation 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 official versions. CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finlan

16、d, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOM

17、ITEE FR NORMUNG Management Centre: Avenue Marnix 17, B-1000 Brussels 2010 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN ISO 6145-9:2010: EContents DIN EN ISO 6145-9:2011-03 EN ISO 6145-9:2010 (E) 2 Page Foreword3 1 Scope 4 2 Norm

18、ative references 4 3 Terms and definitions .4 4 Principle4 5 Equipment 5 5.1 Set up 5 5.2 Gas preparation .5 5.3 Compatibility of the apparatus.5 5.4 Selection of the apparatus5 5.5 Pressure measurement .5 5.6 Temperature control6 5.7 Instrumentation6 5.8 Purity.7 6 Procedure .7 6.1 Installation 7 6

19、.2 Operation of a direct system 7 6.3 Operation of a closed circulation system .7 7 Uncertainty of measurement 8 Annex A (normative) Overview of vapour pressure data for various substances .10 Annex B (informative) Examples of uncertainty estimations .14 Bibliography 17 Foreword The text of ISO 6145

20、-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 as EN ISO 6145-9:2010. This European Standard shall be given the status of a national standard, either by publication of an identical te

21、xt 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 possibility that some of the elements of this document may be the subject of patent rights. CEN and/or CENELEC shall not be held responsible f

22、or identifying any or all such patent rights. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Fran

23、ce, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, 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

24、-9:2010 without any modification. DIN EN ISO 6145-9:2011-03 EN ISO 6145-9:2010 (E) 3 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 cont

25、inuous production of calibration gas mixtures 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 m

26、ethod. Unlike the methods presented in the 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 adso

27、rbed on surfaces, and it is therefore difficult 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

28、occurrence of condensation. The saturation 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 late

29、st edition of the referenced document (including 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 Guidel

30、ines 3 Terms and definitions For the purposes 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, an

31、d in the absence of significant DIN EN ISO 6145-9:2011-03 EN ISO 6145-9:2010 (E) 4 gas 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

32、brought into contact with 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 tempera

33、ture, T1, following which 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, equa

34、l to the ratio of the 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 table

35、s or diagrams in References 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 f

36、irstly through a filter (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

37、the equipment in order 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 exc

38、lusively in materials 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

39、shall be checked before 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 Pre

40、ssure measurement Measure the total pressure at the outlet of the pressure-equalizing vessel. DIN EN ISO 6145-9:2011-03 EN ISO 6145-9:2010 (E) 5 Key 1 supply of complementary gas 2 filter for suspended particles 3 saturator 4 condenser, constructed of a material that is of adequate thermal conductiv

41、ity (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 pro

42、ducing 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

43、heated 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 DI

44、N EN ISO 6145-9:2011-03 EN ISO 6145-9:2010 (E) 6 5.8 Purity Use exclusively components of purity W 99,99 %, because certain impurities, if present, affect the vapour pressure. NOTE It is possible that components of such purity cannot be acquired. If it is desired to apply the method in such cases, a

45、ttention is drawn to 8.2.5 of ISO 6144:20035which outlines the additional factors to be considered relative to the estimate of the expanded relative uncertainty. 6 Procedure 6.1 Installation Arrange the cooling surfaces so as to obtain identical temperatures of the gas and the condenser at the conde

46、nsate outlet. Place the pressure-equalizing vessel with baffles after the condenser in order to remove aerosols from the gas stream. Maintain the pressure-equalizing vessel at the same temperature as the condenser. Ensure that the temperature of the cooling medium in the vessel, holding the condense

47、r and the pressure-equalizing vessel, remains constant by means of suitable cooling and heating elements via a control circuit. In addition to the temperature T2, maintain the pressure, p, of the gas mixture constant in the condenser and display it. Collect the condensate produced in the condenser i

48、n a condensate receiver or remove it continuously by pumping. 6.2 Operation of a direct system Pass the complementary gas into the calibration component in its liquid phase in the saturator (item 3 in Figure 1) at temperature T1. Ensure that the condensation temperature of the calibration component

49、in the flow of complementary gas is higher than the temperature T2of the subsequent condenser (item 4 in Figure 1). Cool the gas mixture in the condenser until some of the calibration component condenses. The condensate is discharged through the condensate outlet (item 9 in Figure 1). The calibration gas mixture from the outlet of the condenser passes through a pressure-equalizing vessel (item 5 in Figure 1) in which any liquid droplets which may still be present are separate