1、raising standards worldwide NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAW BSI Standards Publication PD CEN/TR 15404:2010 Solid recovered fuels Methods for the determination of ash melting behaviour by using characteristic temperaturesPD CEN/TR 15404:2010 PUBLISHED DOCUMENT N
2、ational foreword This Published Document is the UK implementation of CEN/ TR 15404:2010. It supersedes DD CEN/TS 15404:2006 which is withdrawn. The UK participation in its preparation was entrusted to Technical Committee PTI/17, Solid biofuels. A list of organizations represented on this committee c
3、an be obtained on request to its secretary. This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. BSI 2010 ISBN 978 0 580 69900 9 ICS 75.160.10 Compliance with a British Standard cannot confer immunity from legal o
4、bligations. This Published Document was published under the authority of the Standards Policy and Strategy Committee on 31 October 2010. Amendments issued since publication Date Text affectedPD CEN/TR 15404:2010TECHNICAL REPORT RAPPORT TECHNIQUE TECHNISCHER BERICHT CEN/TR 15404 September 2010 ICS 75
5、.160.10 Supersedes CEN/TS 15404:2006 English Version Solid recovered fuels - Methods for the determination of ash melting behaviour by using characteristic temperatures Combustibles solides de rcupration - Mthode de dtermination de la fusibilit des cendres Feste Sekundrbrennstoffe - Verfahren zur Be
6、stimmung des Schmelzverhaltens der Asche bei Anwendung charakteristischer Temperaturen This Technical Report was approved by CEN on 12 June 2010. It has been drawn up by the Technical Committee CEN/TC 343. CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus,
7、Czech Republic, Denmark, Estonia, Finland, 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
8、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 worldwide for CEN national Members. Ref. No. CEN/TR 15404:2010: EPD CEN/TR 15404:2010 CEN/TR 15404:2010 (E) 2 Content
9、s Page Foreword 3 Introduction .4 1 Scope 5 2 Normative references 5 3 Terms and definitions .5 4 Principle 6 5 Reagents .6 6 Apparatus and auxiliary means 6 7 Test conditions 7 8 Methodology .8 9 Procedure .8 10 Evaluation of available results .9 Annex A (informative) Interlaboratory test results 1
10、2 Bibliography . 17 PD CEN/TR 15404:2010 CEN/TR 15404:2010 (E) 3 Foreword This document (CEN/TR 15404:2010) has been prepared by Technical Committee CEN/TC 343 “Solid recovered fuels”, the secretariat of which is held by SFS. Attention is drawn to the possibility that some of the elements of this do
11、cument may be the subject of patent rights. CEN and/or CENELEC shall not be held responsible for identifying any or all such patent rights. This document supersedes CEN/TS 15404:2006. CEN/TS 15404:2006 was not to be kept as a Technical Specification and respectively not converted into a European Sta
12、ndard due to lack of acceptable precision data (see 1, 2). This document differs from CEN/TS 15404:2006 as follows: a) symbol of shrinking temperature changed from ST to SST; b) charts and key of Figure 1 corrected; c) clause “Precision“ deleted; d) clause on evaluation of results added; e) interlab
13、oratory test results supplemented as graphs in an informative annex; f) whole document editorially revised. PD CEN/TR 15404:2010 CEN/TR 15404:2010 (E) 4 Introduction Ash melting is a complex process where also shrinkage, sintering and swelling can occur. The test methods described in this Technical
14、Report provide information about fusion and melting behaviour of the composite inorganic constituents of the fuel ash at high temperatures. The test methods available are empirical in most cases. The ashes used for the tests are homogeneous material, prepared from the fuel, and the determination is
15、performed at a controlled rate of heating in a controlled atmosphere. In contrast, under full-scale conditions, the complex processes of combustion and fusion involve heterogeneous mixtures of particles, variable heating rates and gas compositions. The methods described in this document should be us
16、ed dependent of the following aspects and parameters, respectively: repeatability; reproducibility; reliability; time efforts (rapid test methods); cost effectiveness; possibilities for automatic testing. The aim of this document consists in providing a common and successful practice for describing
17、the ash melting behaviour. The terms ash fusibility and ash softening are synonyms to ash melting. PD CEN/TR 15404:2010 CEN/TR 15404:2010 (E) 5 1 Scope This Technical Report describes exemplarily methods for the determination of shrinking, deformation, hemisphere and flow temperature for characteris
18、ing the ash melting behaviour of all solid recovered fuels. 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 (i
19、ncluding any amendments) applies. prEN 15357:2008, Solid recovered fuels Terminology, definitions and descriptions prEN 15403, Solid recovered fuels Determination of ash content ISO 3310-1, Test sieves Technical requirements and testing Part 1: Test sieves of metal wire cloth 3 Terms and definitions
20、 For the purposes of this document, the terms and definitions given in prEN 15357:2008 and the following apply. 3.1 shrinking temperature SST temperature at which shrinking of the test piece occurs, i.e. when the area of the test piece falls below 95 % of the original test piece area at 550 C NOTE S
21、hrinking can be due to liberation of carbon dioxide, volatile alkali compounds, and/or sintering and partial melting. 3.2 deformation temperature DTtemperature at which the first signs of roundings of the edges due to melting of the test piece occur 3.3 hemisphere temperature HTtemperature at which
22、the test piece forms approximately a hemisphere, i.e. when the height becomes equal to half the base diameter 3.4 flow temperature FTtemperature at which the ash is spread out over the supporting tile in a layer, the height of which as half of the height of the test piece at the hemisphere temperatu
23、re NOTE Half of the height of the test piece is defined due to frequently occurring bubbling effects. This is especially important for automatic image evaluation. This definition is different to other standards. PD CEN/TR 15404:2010 CEN/TR 15404:2010 (E) 6 4 Principle A test piece made from the prep
24、ared ash is heated up with constant rate whereas the deformation is continuously observed. The temperatures at which characteristic changes of the shape occur are recorded. 5 Reagents 5.1 Water, demineralised. 5.2 Dextrin, 100g/l solution: 10 g of dextrin are dissolved in 100 ml water. 5.3 Ethanol,
25、with a purity of greater than 95 %. 5.4 Carbon dioxide 5.5 Gas mixture, of carbon dioxide (5.4) and carbon monoxide: A volume fraction of 55 % to 65 % carbon monoxide is mixed with a volume fraction of 35 % to 45 % carbon dioxide (5.4). 5.6 Gold wire, with a diameter of 0,5 mm or greater, or a gold
26、plate, with a thickness of 0,5 mm to 1,0 mm, a purity of at least 99,99 % and a certified melting point (e.g. 1 064 C). 5.7 Nickel wire, with a diameter of 0,5 mm or greater, or a nickel plate, with a thickness of 0,5 mm to 1,0 mm, a purity of at least 99,9 % and a certified melting point (e.g. 1 45
27、5 C). NOTE Nickel is used for reducing atmosphere. 5.8 Palladium wire, with a diameter of 0,5 mm or greater, or a palladium plate, with a thickness of 0,5 mm to 1,0 mm, a purity of at least 99,9 % and a certified melting point (e.g. 1 554 C). 6 Apparatus and auxiliary means 6.1 Furnace, electrically
28、 heated, capable to: a) reach the maximum temperature ( 1 500 C) at which the properties of the ash shall be determined; b) provide and maintain an adequate zone of uniform temperature which to heat the test piece(s) in; c) provide means for heating the test piece(s) at an uniform rate from 550 C up
29、wards; d) maintain the required test atmosphere around the test piece(s); e) provide means for observing the change of shape of the test piece(s) during heating. 6.2 Dish, consisting of inert material, such as porcelain, silica, platinum, with a depth from 10 mm to 20 mm and of such a size that the
30、sample loading does not exceed 0,1 g/cm 2bottom area. 6.3 Pyrometer, consisting of a platinum/platinum-rhodium thermocouple. 6.4 Mould, of brass, stainless steel or other suitable material for preparing the test piece. 6.5 Spring pressure hand press for producing the test piece, capable of providing
31、 a spring pressure of about 1,5 N/mm 2 . 6.6 Support for the test piece, consisting of such an inert material that it neither is distorted nor absorbs the ash during the determination. PD CEN/TR 15404:2010 CEN/TR 15404:2010 (E) 7 NOTE Supports of sintered alumina or fine-textured mullite are general
32、ly satisfactory but difficulties can arise with individual ashes, in which case a non-absorbent interface such as platinum foil can be used between the original support and the test piece. 6.7 Flowmeters, two, for measuring the components of the reducing gases. NOTE If using oxidising gas, it is not
33、 necessary to measure the flow rate. 6.8 Grinding device, such as agate mortar and pestle. 6.9 Test sieve, of aperture 0,075 mm and diameter of at least 100 mm complete with lid and receiver, in accordance with ISO 3310-1. 6.10 Optical instrument, such as a camera or video equipment, for observing t
34、he profile of the test piece throughout the determination. 7 Test conditions 7.1 Test atmosphere Oxidising or reducing atmosphere is used depending on the application. Air or carbon dioxide is applied for an oxidising atmosphere. For a reduced atmosphere, the following mixtures shall be passing the
35、test piece at a minimum linear rate of flow from 100 mm/min to 250 mm/min calculated at ambient temperature: 55 % volume fraction to 65 % volume fraction carbon monoxide with 35 % volume fraction to 45 % volume fraction carbon dioxide, and 45 % volume fraction to 55 % volume fraction hydrogen with 4
36、5 % volume fraction to 55 % volume fraction carbon dioxide. NOTE The flow rate is not very critical, provided that it is sufficient to prevent any leakage of air into the furnace in case of reducing atmosphere. However, the same flow rate level is also recommended for oxidising atmosphere. For open-
37、type furnaces with a larger diameter, a flow rate of about 400 mm/min could be needed for reducing atmosphere. In all cases it should also be referred to manufacturer instructions. The flow rate for rotameter adjustment can be calculated by multiplying the flow rate, expressed in millimetres per min
38、ute, with the inside cross-section area of the furnace tube converting into litres per minute. WARNING When using reduced atmosphere as given above, the gases emerging from the furnace will contain a proportion of carbon monoxide; therefore it is essential to ensure that these gases are vented to th
39、e outside atmosphere, preferably by means of a hood or an efficient fan system. If hydrogen is used in the reducing atmosphere, care shall be taken to prevent an explosion occurring by purging with carbon dioxide both prior to the introduction of the hydrogen and after the hydrogen supply is shut of
40、f. 7.2 Shape of test piece The test piece shall have sharp edges to facilitate observation. The mass of the test piece shall be such as to ensure equalisation of the temperature within the test piece. Hence, dimensions that are too large shall be avoided. Several test piece shapes are used, e.g. cyl
41、inders, pyramids, cubes, truncated pyramids, with dimensions (diameter or height) in the vicinity of 3 mm to 5 mm. Figure 1 illustrates a cylindrical shape test piece at the various characteristic temperatures. PD CEN/TR 15404:2010 CEN/TR 15404:2010 (E) 8 Key 1 original sample 2 sample at shrinkage
42、temperature 3 sample at deformation temperature 4 sample at hemisphere temperature 5 sample at flow temperature Figure 1 Phases in the ash melting process (original shape = = = = shape and size at 550 C) 8 Methodology The ash shall be prepared in accordance with prEN 15403 (see also prEN 15442 and p
43、rEN 15443). A complete incineration of the sample is of paramount importance. The ash is grinded until the maximum particle size is less than 0,075 mm. None of the ash may be withdrawn during grinding. A sufficient quantity of the prepared ash with a particle size less than 0,075 mm is moistened wit
44、h water (5.1), dextrin (5.2) or ethanol (5.3), made into a paste and pressed into a mould. Then allow the test piece to dry. 9 Procedure The test piece is transferred on the support (6.6) into the furnace (6.1) and the composition and flow rate of the atmosphere adjusted. The temperature is raised a
45、t a uniform rate within the range of 3 K/min to 10 K/min. A picture is taken at least every 10 K. Then the temperature is raised to a point below the expected deformation temperature such that the temperature interval between the point and the expected deformation temperature exceeds 150 C. If possi
46、ble, shrinking, deformation, hemisphere and flow temperatures are determined. NOTE 1 There are several standard methods, e.g. DIN 51730, to determine the ash melting behaviour of solid fuels and there are minor differences in the methodology and the interpretation of characteristic temperatures that
47、 should be noted, especially the shape of the test piece and the definition of the characteristic temperatures. NOTE 2 Using a computerised image evaluation, the deformation temperature is reached if the shape factor F has changed by 1,5 %. In order to determine the shape factor, the circumference o
48、f a perfect semicircle with the same area as the shadow of the test piece is calculated. This idle circumference b is then put in relation to the actual measured circumference a of the test piece. This relation gives the shape factor F = b/a. A schematic of the images obtained by the computerized ev
49、aluation is shown in Figure 2. PD CEN/TR 15404:2010 CEN/TR 15404:2010 (E) 9 Key A shadow area of the test piece (actual image) A area of the test piece after computerized image evaluation (equivalent to the shadow area) a actual measured circumference b idle circumference Figure 2 Schematic of the images obtained by the computerised evaluation In the case of some ashes, difficulties can be encountered owing to such effects as blistering, distortion, shrinking, swelling, non-wetting of the support caused by high surface tension and
