ISO TS 13605-2012 Solid mineral fuels - Major and minor elements in hard coal ash and coke ash - Wavelength dispersive X-ray fluorescence spectrometric method《固.pdf

1、 ISO 2012 Solid mineral fuels Major and minor elements in hard coal ash and coke ash Wavelength dispersive X-ray fluorescence spectrometric method Combustibles minraux solides lments en minorit et en majorit dans les cendres de houille et de coke Mthode spectromtrique par fluorescence aux rayons X u

2、ne longueur donde dispersive TECHNICAL SPECIFICATION ISO/TS 13605 First edition 2012-05-15 Reference number ISO/TS 13605:2012(E) ISO/TS 13605:2012(E) ii ISO 2012 All rights reserved COPYRIGHT PROTECTED DOCUMENT ISO 2012 All rights reserved. Unless otherwise specified, no part of this publication may

3、 be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from either ISO at the address below or ISOs member body in the country of the requester. ISO copyright office Case postale 56 CH-1211 Geneva 20 Tel.

4、+ 41 22 749 01 11 Fax + 41 22 749 09 47 E-mail copyrightiso.org Web www.iso.org Published in Switzerland ISO/TS 13605:2012(E) ISO 2012 All rights reserved iii Contents Page Foreword iv 1 Scope 1 2 Normative references . 2 3 Terms and definitions . 2 4 Principle . 2 5 Reagents 2 5.1 General . 2 5.2 F

5、lux and heavy absorber . 2 6 Apparatus 2 6.1 General . 2 6.2 Crucible 3 6.3 Mould 3 6.4 Crucible tongs 3 6.5 Desiccator . 3 6.6 Sample holders 3 6.7 X-ray fluorescence spectrometer 3 7 Sample 4 7.1 Coal and coke ash prepared in the laboratory 4 7.2 Coal and coke ash . 4 8 Procedure 4 8.1 Number of d

6、eterminations 4 8.2 Test portion . 4 8.3 Check test 4 8.4 Calibration . 4 8.5 Preparation of the fused discs . 5 8.6 XRF measurement . 6 9 Calculation 7 9.1 General . 7 9.2 Correction of instrumental drift . 7 9.3 Correction for dead time losses 7 9.4 Matrix corrections . 8 10 Reporting results . 8

7、11 Precision 8 12 Test report . 9 Annex A (normative) Acceptance of analytical results for laboratory method 10 Annex B (informative) Reagents suitable for the preparation of synthetic calibration standards 12 Annex C (normative) Standard deviation of glass disc preparation 13 Bibliography .15 ISO/T

8、S 13605:2012(E) Foreword 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 subje

9、ct 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

10、) 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 committe

11、es 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. In other circumstances, particularly when there is an urgent market requirement for such documents, a technical committee may decide to

12、publish other types of document: an ISO Publicly Available Specification (ISO/PAS) represents an agreement between technical experts in an ISO working group and is accepted for publication if it is approved by more than 50 % of the members of the parent committee casting a vote; an ISO Technical Spe

13、cification (ISO/TS) represents an agreement between the members of a technical committee and is accepted for publication if it is approved by 2/3 of the members of the committee casting a vote. An ISO/PAS or ISO/TS is reviewed after three years in order to decide whether it will be confirmed for a f

14、urther three years, revised to become an International Standard, or withdrawn. If the ISO/PAS or ISO/TS is confirmed, it is reviewed again after a further three years, at which time it must either be transformed into an International Standard or be withdrawn. Attention is drawn to the possibility th

15、at some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. ISO/TS 13605 was prepared by Technical Committee ISO/TC 27, Solid mineral fuels, Subcommittee SC 5, Methods of analysis. iv ISO 2012 All righ

16、ts reserved TECHNICAL SPECIFICATION ISO/TS 13605:2012(E) Solid mineral fuels Major and minor elements in hard coal ash and coke ash Wavelength dispersive X-ray fluorescence spectrometric method WARNING Use of this Technical Specification can involve hazardous materials, operations and equipment. Thi

17、s Technical Specification does not purport to address all of the safety problems associated with its use. It is the responsibility of the user of this Technical Specification to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

18、1 Scope This Technical Specification sets out a wavelength dispersive X-ray fluorescence (XRF) procedure for the determination of silicon, aluminium, iron, calcium, magnesium, sodium, potassium, titanium, manganese, phosphorus and sulfur. The method is applicable to coal ashes, coke ashes and boiler

19、 ashes having components within the concentration ranges specified in Table 1. Table 1 Ranges of application of the method Oxide Concentration range % SiO 2 5100 Al 2 O 3 580 Fe 2 O 3 0,125 CaO 0,0525 MgO 0,0525 Na 2 O 0,055 K 2 O 0,055 TiO 2 0,055 Mn 3 O 4 0,0055 P 2 O 5 0,015 SO 3 0,0510 NOTE 1 Ad

20、ditional analytes may be included in the method, provided that appropriate validation using reference materials is carried out. NOTE 2 The precision statistics can be determined using suitable reference materials. NOTE 3 The method described in this Technical Specification has been tested for the fo

21、llowing additional analytes: BaO (0,01 % to 1 %); SrO (0,01 % to 1 %) and ZnO (0,005 % to 1 %). ISO 2012 All rights reserved 1 ISO/TS 13605:2012(E) 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition

22、 cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. ISO 1171, Solid mineral fuels Determination of ash ISO 1213-2, Solid mineral fuels Vocabulary Part 2: Terms relating to sampling, testing and analysis ISO 13909-4, Hard coal and

23、coke Mechanical sampling Part 4: Coal Preparation of test samples ISO 13909-6, Hard coal and coke Mechanical sampling Part 6: Coke Preparation of test samples 3 Terms and definitions For the purposes of this document, the terms and definitions given in ISO 1213-2 apply. 4 Principle The specimen on w

24、hich X-ray fluorescence measurements are made is prepared by incorporating the test portion of the sample, via fusion, into a borate glass disc using a casting or press-quenching procedure. By using such a specimen, particle size effects are eliminated. Calibration is carried out using pure chemical

25、s and/or reference standards, and by making matrix corrections for inter-element effects. It is expected that laboratories using this Technical Specification have experience in analysing coal ashes of certain compositions and that they employ calibrations that cover these compositions. 5 Reagents 5.

26、1 General Unless otherwise specified, all reagents shall be of analytical grade and only distilled water or water of equivalent purity shall be used. 5.2 Flux and heavy absorber Borate fluxes of differing compositions have been found suitable for preparing glass discs from coal/coke ash samples. The

27、se fluxes are based on mixtures of one or more of the following: lithium tetraborate, lithium metaborate and lanthanum oxide. Flux may be purchased commercially or prepared by fusion of a mixture of individual reagents. NOTE The levels of contamination in the flux should be checked. Because levels o

28、f contamination may vary from batch to batch, the same batch of flux should be used for all specimens (synthetic standards, external standards and unknowns). When using a fresh batch of flux, reference material specimens should be prepared to determine whether adjustments to the calibration are requ

29、ired. 6 Apparatus 6.1 General All apparatus shall be constructed from materials that are thermally stable and chemically inert under the conditions of the procedure. 2 ISO 2012 All rights reserved ISO/TS 13605:2012(E) 6.2 Crucible The crucible shall be made from a non-wetting platinum alloy. The cru

30、cible shall have sufficient capacity to hold the flux and sample required for fusion. Normally, 15 ml crucibles are adequate for discs of 32 mm in diameter, and 25 ml crucibles for discs of 40 mm in diameter. NOTE Either platinum/gold or platinum/gold/rhodium alloys are suitable. Because the crucibl

31、e and lid (if used) are to be used for fusion work, the normal precautions associated with the care of hot platinum ware should be observed. It is necessary, therefore, to have suitable tongs and a surface on which to rest the crucible. The hot crucible can be rested on a refractory surface, which s

32、hall be kept very clean. Although the crucible is fabricated from an alloy that is not wetted by the glass, for the greatest precision, the crucible should be cleaned between each fusion. The use of citric acid (mass concentration of 20 %), dilute hydrochloric acid (volume fraction of 10 %50 %) or d

33、ilute chlorine-free nitric acid (volume fraction of 10 %) have proven to be suitable for crucible cleaning. The use of an ultrasonic bath will accelerate this process. An alternative method of cleaning is to fuse several grams of flux in the crucible, moving the melt around so as to clean the entire

34、 inner surface. The molten flux is poured from the crucible. If a droplet adheres to the crucible, this can easily be flaked off when the crucible is cold. 6.3 Mould The mould shall be made from non-wetting material. For example, platinum alloy is commonly used for casting discs, and aluminium or gr

35、aphite is suitable for press quenching. In the casting technique, the bottom of the disc is the analytical surface. The mould should therefore be flat and sufficiently thick that it is not easily deformed. Casting moulds should be checked regularly for flatness and should be polished regularly, to e

36、nsure that the disc releases from the mould. Platens for press-quenching are constructed so that the depth gradually increases from the perimeter to the centre. The analytical surface for press-quenched discs is the surface which contacts the plunger head. Care should be taken not to choose the plat

37、en side for intensity measurements. 6.4 Crucible tongs The crucible tongs shall be platinum-tipped or stainless steel or titanium. NOTE Stainless steel or titanium tongs are a suitable alternative to platinum-tipped tongs. 6.5 Desiccator The desiccator shall contain freshly regenerated, self-indicat

38、ing silica gel. 6.6 Sample holders Sample holders shall be used for specimen presentation. 6.7 X-ray fluorescence spectrometer Any conventional wavelength dispersive (sequential, simultaneous, or combination simultaneous/sequential) vacuum path X-ray fluorescence spectrometer may be used, provided t

39、hat it conforms to precision requirements at the 0,1 % (10 6counts) precision level. ISO 2012 All rights reserved 3 ISO/TS 13605:2012(E) 7 Sample 7.1 Coal and coke ash prepared in the laboratory The coal or coke sample shall be the analysis sample, prepared to a nominal top size of 212 m. Sample pre

40、paration shall be in accordance with ISO 13909-4 for coal samples or ISO 13909-6 for coke samples. The sample shall then be ashed using the procedure specified in ISO 1171. 7.2 Coal and coke ash Coal or coke ash received at the laboratory shall be heated at 815 C for 15 min and cooled in a desiccato

41、r over freshly regenerated, self-indicating silica gel immediately prior to weighing for analysis. Boiler ash received at the laboratory should be ground to a nominal top size of 63 m and dried at 105 C for 1 h, then stored in a desiccator over freshly regenerated, self-indicating silica gel. 8 Proc

42、edure 8.1 Number of determinations Discs shall be prepared and analysed as single determinations and a reference material shall be prepared and analysed at the beginning and end of each batch of samples containing a maximum of 25 samples. 8.2 Test portion The mass of the test portion shall be approp

43、riate for the mould size and sample flux ratio chosen. NOTE 1 Typically, sample-to-flux ratios are in the range 1:5 to 1:10. NOTE 2 Typical total mass (sample plus flux) is 4 g for a 32 mm diameter and 7,5 g for a 40 mm diameter mould. 8.3 Check test At least one reference material of similar compos

44、ition to the samples being analysed shall be included with each batch of test samples and shall be analysed in parallel with, and under the same conditions as, the test samples. The results for the batch of samples shall be rejected if the results for the reference material fail to meet the acceptan

45、ce criteria detailed in Annex A. 8.4 Calibration Calibration shall be effected using either reference materials, synthetic standards or mixtures of reference materials and synthetic standards. Reference materials shall be pre-treated in accordance with the instructions contained on their certificate

46、s. If synthetic standards are used, stoichiometric chemicals of appropriate purity shall be used. Chemicals of 99,99 % or higher purity are recommended. Pure chemicals shall be appropriately pre-treated, immediately prior to weighing to ensure stoichiometry and freedom from moisture. Calibration dis

47、cs shall be prepared in accordance with 8.5. NOTE Reagents suitable for the preparation of synthetic calibration standards and their appropriate pre-treatment conditions are listed in Annex B. 4 ISO 2012 All rights reserved ISO/TS 13605:2012(E) 8.5 Preparation of the fused discs 8.5.1 General A numb

48、er of different fluxes and sample-to-flux ratios have proven suitable for the preparation of fused discs that are acceptable for XRF analysis of samples of coal or coke ash. Any consistent combination of sample mass, flux mass and flux type may be used to prepare the fused discs, provided that a) di

49、sc preparation quality conforms to the requirements of Annex C, and b) the precision and accuracy of reference materials prepared using this sample flux combination conforms to the requirements of Annex A. Discs may be prepared by the casting or press-quenching technique. Both methods will produce glass discs of adequate quality. If the casting technique is used, the sample may be fused with the flux in a crucible and then poured into a separate mould; if an appropriately shaped crucible is used,