1、DRAFT FOR DEVELOPMENTDD CEN/TS 15370-1:2006Solid biofuels Method for the determination of ash melting behaviour Part 1: Characteristic temperatures methodICS 75.160.10g49g50g3g38g50g51g60g44g49g42g3g58g44g55g43g50g56g55g3g37g54g44g3g51g40g53g48g44g54g54g44g50g49g3g40g59g38g40g51g55g3g36g54g3g51g40g5
2、3g48g44g55g55g40g39g3g37g60g3g38g50g51g60g53g44g42g43g55g3g47g36g58DD CEN/TS 15370-1:2006This Draft for Development was published under the authority of the Standards Policy and Strategy Committee on 28 February 2007 BSI 2007ISBN 978 0 580 50255 2National forewordThis Draft for Development was publi
3、shed by BSI. It is the UK implementation of CEN/TS 15370-1:2006.This publication is not to be regarded as a British Standard.It is being issued in the Draft for Development series of publications and is of a provisional nature. It should be applied on this provisional basis, so that information and
4、experience of its practical application can be obtained.Comments arising from the use of this Draft for Development are requested so that UK experience can be reported to the European organization responsible for its conversion to a European standard. A review of this publication will be initiated n
5、ot later than 3 years after its publication by the European organization so that a decision can be taken on its status. Notification of the start of the review period will be made in an announcement in the appropriate issue of Update Standards.According to the replies received by the end of the revi
6、ew period, the responsible BSI Committee will decide whether to support the conversion into a European Standard, to extend the life of the Technical Specification or to withdraw it. Comments should be sent to the Secretary of the responsible BSI Technical Committee at British Standards House, 389 Ch
7、iswick High Road, London W4 4AL.The UK participation in its preparation was entrusted to Technical Committee PTI/17, Solid biofuels.A list of organizations represented on PTI/17 can be obtained on request to its secretary.This publication does not purport to include all the necessary provisions of a
8、 contract. Users are responsible for its correct application.Amendments issued since publicationAmd. No. Date CommentsTECHNICAL SPECIFICATIONSPCIFICATION TECHNIQUETECHNISCHE SPEZIFIKATIONCEN/TS 15370-1September 2006ICS 75.160.10English VersionSolid biofuels - Method for the determination of ash melt
9、ingbehaviour - Part 1: Characteristic temperatures methodBiocombustibles solides - Mthode de dtermination de lafusibilit des cendres - Partie 1: Mthode des tempraturescaractristiquesFeste Biobrennstoffe - Verfahren zur Bestimmung desSchmelzverhaltens der Asche - Teil 1: Verfahren zurBestimmung chara
10、kteristischer TemperaturenThis Technical Specification (CEN/TS) was approved by CEN on 28 February 2006 for provisional application.The period of validity of this CEN/TS is limited initially to three years. After two years the members of CEN will be requested to submit theircomments, particularly on
11、 the question whether the CEN/TS can be converted into a European Standard.CEN members are required to announce the existence of this CEN/TS in the same way as for an EN and to make the CEN/TS availablepromptly at national level in an appropriate form. It is permissible to keep conflicting national
12、standards in force (in parallel to the CEN/TS)until the final decision about the possible conversion of the CEN/TS into an EN is reached.CEN members are the national standards bodies of Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France,Germany, Greece, Hungary, Iceland, Ire
13、land, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania,Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.EUROPEAN COMMITTEE FOR STANDARDIZATIONCOMIT EUROPEN DE NORMALISATIONEUROPISCHES KOMITEE FR NORMUNGManagement Centre: rue de Stassart, 36
14、 B-1050 Brussels 2006 CEN All rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. CEN/TS 15370-1:2006: E2 Contents Page Foreword .3 Introduction.4 1 Scope5 2 Normative references5 3 Terms and Definitions.5 4 Principle .5 5 Reagents 6 6 Apparatus.6
15、7 Test conditions7 8 Calibration check.8 9 Preparation of the test piece 8 10 Procedure.9 11 Precision of the method9 12 Test report9 Annex A .10 Bibliography11 CEN/TS 15370-1:20063 Foreword This document (CEN/TS 15370-1:2006) has been prepared by Technical Committee CEN/TC 335 “Solid biofuels”, the
16、 secretariat of which is held by SIS. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to announce this Technical Specification: Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, H
17、ungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. CEN/TS 15370-1:20064 Introduction Ash melting is a complex process where also sintering, shrinkage and swelling ca
18、n occur. The test method described in this Technical Specification provides information about fusion and melting behaviour of the composite inorganic constituents of the fuel ash at high temperatures. The test method is empirical. The ash used for the test is a homogeneous material, prepared from th
19、e fuel, and the determination is 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 determined cha
20、racteristic temperatures in the test can be used for comparison of the tendency of the ashes from different types and qualities of solid biofuels to form fused deposits or to cause bed agglomeration on heating. The method is based on the methods described in ISO 540:1995 and DIN 51730:1998. The term
21、s ash fusibility and ash softening are synonyms to ash melting. CEN/TS 15370-1:20065 1 Scope This document specifies a method for the determination of the characteristic temperatures for the ash melting behaviour of solid biofuels. 2 Normative references The following referenced documents are indisp
22、ensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. CEN/TS 14588:2003, Solid Biofuels Terminology, definitions and descriptions CEN/TS 14775:2004,
23、 Solid Biofuels Method for the determination of ash content 3 Terms and Definitions For the purposes of this Technical Specification, the terms and definitions given in CEN/TS 14588:2003 shall apply together with the following. 3.1 Shrinkage starting temperature (abbreviation: SST): The temperature
24、at which shrinking of the test piece occurs. This temperature is defined as when the area of the test piece falls below 95 % of the original test piece area at 550 oC. NOTE Shrinking may be due to liberation of carbon dioxide, volatile alkali compounds, and/or sintering. 3.2 Deformation temperature
25、(abbreviation: DT): The temperature at which the first signs of rounding of the edges of the test piece occurs due to melting. NOTE For computerised evaluation a shape factor change of 15 % marks the deformation temperature. For definition of shape factor see normative Annex A. 3.3 Hemisphere temper
26、ature (abbreviation: HT): The temperature at which the test piece forms approximately a hemisphere i.e. when the height becomes equal to half the base diameter. 3.4 Flow temperature (abbreviation: FT): The temperature at which the ash is spread out over the supporting tile in a layer, the height of
27、which is half of the height of the test piece at the hemisphere temperature. NOTE Half of the height of the test piece has been defined due to frequently occurring bubbling effects. This is especially important for automatic image evaluation. Be aware that this definition is different to other stand
28、ards. 4 Principle A test piece made from a prepared ash is heated up with constant rate and continuously observed. The temperatures at which characteristic changes of the shape occur are recorded. The characteristic temperatures are defined in Clause 3 (see also Figure 1). CEN/TS 15370-1:20066 5 Rea
29、gents 5.1 Demineralised water. 5.2 Dextrin, 100 g/l solution. Dissolve 10 g of dextrin in 100 ml of water. 5.3 Ethanol, with a purity 95 %. 5.4 Gold wire, of diameter 0,5 mm or larger, or gold plate, of thickness 0,5 mm to 1,0 mm with a purity of 99,99 % or a certified melting point (e.g. 1064 C). 5
30、.5 Nickel wire, of diameter 0,5 mm or larger, or nickel plate, of thickness 0,5 mm to 1,0 mm, with a purity of 99,9 % or a certified melting point (e.g. 1455 C). Nickel is used for reducing atmosphere. 5.6 Palladium wire, of diameter 0,5 mm or larger, or palladium plate, of thickness 0,5 mm to 1,0 m
31、m with a purity of 99,9 % or a certified melting point (e.g.1554 C). 5.7 Carbon dioxide, carbon monoxide, hydrogen or ready mixture of carbondioxide and carbon monoxide with 55 % (V/V) to 65 % (V/V) carbon monoxide and 35 % (V/V) to 45 % (V/V) carbon dioxide or ready mixture of hydrogen and carbon d
32、ioxide with 45 % (V/V) to 55 % (V/V) hydrogen and 45 % (V/V) to 55 % (V/V) carbon dioxide. 6 Apparatus 6.1 Furnace, electrically heated, which satisfies the following conditions: a) it shall be capable of reaching the maximum temperature at which the properties of the ash are to be determined (a tem
33、perature of 1500 C or more may be required); b) it shall provide an adequate zone of uniform temperature in which to heat the test piece(s); c) it shall provide means of heating the test piece(s) at a uniform rate from 550 C upwards; d) it shall be capable of maintaining the required test atmosphere
34、 (see 7.1) around the test piece(s); e) it shall provide means of observing the change of shape of the test piece(s) during heating. 6.2 Pyrometer, comprising a platinum/platinum-rhodium thermocouple. 6.3 Mould, of brass, stainless steel or other suitable material for preparing the test piece. 6.4 H
35、and press with spring pressure compression, to produce the test piece. The required spring pressure is about 1,5 N/mm2. CEN/TS 15370-1:20067 6.5 Support for the test piece, of such a material that it becomes neither distorted, not reacts with nor absorbs the ash during the determination. Support of
36、sintered alumina or fine textured mullite are generally satisfactory, but difficulties may arise with individual ashes, in which case zirconium supports or a non-absorbent interface such as platinum foil may be used between the original support and the test piece. 6.6 Flowmeters, for measuring the c
37、omponents of the reducing gases (See 7.1) and/or for measuring the flow rate of the oxidizing gas. 6.7 Agate mortar and pestle or other adequate grinding instruments. 6.8 Test sieve, of aperture 0,075 mm (e.g. diameter of 100 mm or smaller, preferable completed with lid and receiver). 6.9 Optical in
38、strument, which enables the profile of the test piece to be observed throughout the determination, by using a camera or video equipment. 7 Test conditions 7.1 Test atmosphere An oxidizing or reducing atmosphere depending on the application can be used. An oxidizing atmosphere is obtained with air or
39、 carbon dioxide. The reducing atmosphere is obtained by introducing a mixture of a) 55 % (V/V) to 65 % (V/V) carbon monoxide with 35 % (V/V) to 45 % (V/V) carbon dioxide or b) 45 % (V/V) to 55 % (V/V) hydrogen with 45 % (V/V) to 55 % (V/V) carbon dioxide into the furnace at a minimum linear rate of
40、flow past the test piece between 100 250 mm/min, calculated at ambient temperature. NOTE The flow rate is not very critical, provided that in the case of reducing atmosphere it is sufficient to prevent any leakage of air into the furnace. However, the same flow rate level is recommended also for oxi
41、dizing atmosphere. For furnaces with larger diameter a flow around 400 mm/min for reducing atmosphere may be needed. In all cases refer also to manufacturer instructions. The flow rate for rotameter adjustment can be calculated by multiplying the flow rate in mm/min with the inside cross-section are
42、a of the furnace tube and converting to units litres/min. WARNING: When using the reducing atmosphere given above, the gases emerging from the furnace will contain a proportion of carbon monoxide; it is essential, therefore, to ensure that these gases are vented to the outside atmosphere, preferably
43、 by means of a hood or an efficient fan system. If hydrogen is used in the reducing atmosphere, great 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 off. 7.2 Shape of test piec
44、e The test piece shall have sharp edges to facilitate observation. The mass of the test piece shall be such as to ensure equalization of the temperature within the test body. Hence, dimensions that are too large shall be avoided. CEN/TS 15370-1:20068 As test piece use an upright cylinder of height 3
45、 mm to 5 mm and with diameter equal to the height (see Figure 1). Figure 1 - Phases in the ash melting process (original shape = shape and size at 550 C) 8 Calibration check Check the pyrometer regularly under routine test conditions by observations of the melting point of gold (5.4) and, if possibl
46、e in the maximum temperature of the furnace (6.1a), the melting point of palladium (5.6). Test the reducing atmosphere by observing the melting point of nickel (5.5). If the observed melting points for gold or palladium differ by more than 10 C from the melting points of the materials given in 5.4 a
47、nd 5.6 readjust or recalibrate. An alternative to the observations of the melting points of gold and palladium is to check the pyrometer using a thermocouple certified by a recognized reference laboratory or with a calibration which is traceable back to a standard reference laboratory. lf the observ
48、ed melting point for nickel differs by more than 10 C from the melting point given in 5.5, it can be due to oxidation of nickel caused by an insufficiently reducing atmosphere. Examine the apparatus for leakages, control the flow rate and the quality of the gases and recheck the melting point of nic
49、kel. NOTE The correct melting point of nickel is not a guarantee that the composition of the reducing atmosphere is correct, as deviations should be considerable before the fusibility is affected. 9 Preparation of the test piece Prepare a sufficient amount of ash according to the method specified in CEN/TS 14775. In deviation of CEN/TS 14775, larger plate type dishes or crucibles for the preparation of the ash can be used. The use of additives to ensure complete combustion is not allowed. Continuous ashing by refilling of the sample on the previous ash in
