1、BSI Standards PublicationBS ISO 502:2015Coal Determination ofcaking power Gray-Kingcoke testBS ISO 502:2015 BRITISH STANDARDNational forewordThis British Standard is the UK implementation of ISO 502:2015.The UK participation in its preparation was entrusted to TechnicalCommittee PTI/16, Solid minera
2、l fuels.A list 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. The British Standards Institution 2015. Published by BSI
3、StandardsLimited 2015ISBN 978 0 580 84504 8ICS 73.040Compliance with a British Standard cannot confer immunity fromlegal obligations.This British Standard was published under the authority of theStandards Policy and Strategy Committee on 30 June 2015.Amendments issued since publicationDate Text affe
4、ctedBS ISO 502:2015 ISO 2015Coal Determination of caking power Gray-King coke testCharbon Dtermination du pouvoir agglutinant Essai Gray-KingINTERNATIONAL STANDARDISO502Third edition2015-06-15Reference numberISO 502:2015(E)BS ISO 502:2015ISO 502:2015(E)ii ISO 2015 All rights reservedCOPYRIGHT PROTEC
5、TED DOCUMENT ISO 2015, Published in SwitzerlandAll rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on the internet or an intranet, without prior
6、written permission. Permission can be requested from either ISO at the address below or ISOs member body in the country of the requester.ISO copyright officeCh. de Blandonnet 8 CP 401CH-1214 Vernier, Geneva, SwitzerlandTel. +41 22 749 01 11Fax +41 22 749 09 47copyrightiso.orgwww.iso.orgBS ISO 502:20
7、15ISO 502:2015(E)Foreword ivIntroduction v1 Scope . 12 Normative references 13 Principle 14 Reagent . 14.1 Standard electrode carbon (see 10.1) . 15 Apparatus . 26 Preparation of sample 27 Procedure. 37.1 Coals with a Gray-King coke type within the range A to G2(see 10.3) . 37.2 Coals with a Gray-Ki
8、ng coke type greater than G2(see 10.3) . 38 Expression of results 39 Precision of the method 39.1 General . 39.2 Repeatability . 49.3 Reproducibility . 410 Notes on procedure 411 Test report . 5Annex A (normative) Determination of the bulk density of electrode carbon 11 ISO 2015 All rights reserved
9、iiiContents PageBS ISO 502:2015ISO 502:2015(E)ForewordISO (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 memb
10、er body interested in a subject 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 Ele
11、ctrotechnical Commission (IEC) on all matters of electrotechnical standardization.The procedures used to develop this document and those intended for its further maintenance are described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the different types
12、of ISO documents should be noted. This document was drafted in accordance with the editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).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 hel
13、d responsible for identifying any or all such patent rights. Details of any patent rights identified during the development of the document will be in the Introduction and/or on the ISO list of patent declarations received (see www.iso.org/patents).Any trade name used in this document is information
14、 given for the convenience of users and does not constitute an endorsement.For an explanation on the meaning of ISO specific terms and expressions related to conformity assessment, as well as information about ISOs adherence to the WTO principles in the Technical Barriers to Trade (TBT) see the foll
15、owing URL: Foreword - Supplementary informationThe committee responsible for this document is ISO/TC 27, Solid mineral fuels, Subcommittee SC 05, Methods of analysis.This third edition cancels and replaces the second edition (ISO 502:1982), which has been technically revised.iv ISO 2015 All rights r
16、eservedBS ISO 502:2015ISO 502:2015(E)IntroductionThe purpose of the Gray-King coke test, which is one of the parameters adopted for the International Classification of Hard Coal by Type by the United Nations Economic Commission for Europe, is to assess the caking properties of a type of coal or a bl
17、end of coals by carbonizing under standard conditions.Although the Gray-King test and the Roga test both assess the caking properties of a coal, they do not measure precisely the same parameters and are not recommended to be regarded as alternative methods. ISO 2015 All rights reserved vBS ISO 502:2
18、015BS ISO 502:2015Coal Determination of caking power Gray-King coke test1 ScopeThis International Standard specifies a method of assessing the caking power of coal under standard conditions.2 Normative referencesThe following documents, in whole or in part, are normatively referenced in this documen
19、t and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.ISO 1014, Coke Determination of true relative density, apparent relative density and porosity3 P
20、rincipleThe sample is heated under standard conditions to a final temperature of 600 C. The coke residue obtained is classified by reference to a series of standard residues. If the coke residue produced is so swollen that it fills the cross-section of the retort tube, the determination is repeated
21、with the coal admixed with a suitable quantity of electrode carbon or equivalent material. For these highly swelling coals, the Gray-King coke type is defined by the minimum amount of electrode carbon required to produce a strong hard coke residue of the same volume as the original coal and electrod
22、e carbon mixture.4 Reagent4.1 Standard electrode carbon (see 10.1)High temperature electrode carbon:Moisture less than 1 %Volatile matter less than 1,5 %Ash less than 5 %Bulk density at 25 C (see Annex A) 1,00 g/cm3 to 1,05 g/cm3Relative density at 25 C (see 10.2) 2,05 to 2,09Size analysis:Retained
23、on 212 m test sieve nilThrough 212 m test sieve, retained on 125 m test sieve less than 26 %Through 125 m test sieve, retained on 63 m test sieve 10 % to 40 %Through 63 m test sieve 50 % to 85 %INTERNATIONAL STANDARD ISO 502:2015(E) ISO 2015 All rights reserved 1BS ISO 502:2015ISO 502:2015(E)It is r
24、ecommended that a dust mask is used while using the inert carbonaceous material which can contain undesirable trace elements from the original processing of this material.5 Apparatus5.1 Furnace, horizontal electric, 50 mm internal diameter and 300 mm long, with one end closed and the other carrying
25、a plug of insulating material which is bored centrally with a hole 25 mm in diameter. The winding of the furnace shall be such that the middle 200 mm is at a uniform temperature within 5 C at both 300 C and 600 C. Alternatively, the furnace may be constructed from an electrically-heated aluminium-br
26、onze block, with one or several, bores of 25 mm diameter. The furnace shall be insulated and located in a cover of metal or other suitable material, and shall be equipped with a suitable thermocouple, lying above the retort tube when the latter is in position and with the junction at the centre of t
27、he furnace. An indicator shall be provided for showing the furnace temperature with an accuracy of 5 C. A suitable means of controlling the energy input shall also be provided to permit an increase in temperature at a rate of 5 C/min. A multiple tube furnace to allow simultaneous determinations is c
28、onvenient. The furnace may be of the fixed type or mounted on rails. Suitable furnaces are shown in Figure 2 and Figure 3.5.2 Retort tube (see Figure 4), a heat-resistant glass or transparent silica tube, 20 mm internal diameter and 300 mm long, closed at one end, with a side arm, 8 mm internal diam
29、eter and 50 mm long, sealed in at a distance of about 20 mm from the open end. The tube shall be smooth and either of uniform bore or with a slight taper (19 mm to 21 mm) such that the open end is the larger.5.3 Distance rod, with a flat disk at one end to assist in the packing of the coal and to in
30、dicate the free end of the coal sample in the retort tube.5.4 Receiver and outlet tubeA glass vessel of adequate size, suitably supported and attached to the side arm of the retort tube, fitted with an outlet tube leading to atmosphere or to a piece of small bore silica tubing at the end of which th
31、e gas leaving the receiver can be burned through Bunsen burner (in a fume cabinet) to ensure toxic fumes are burnt before venting to the atmosphere through the fume cabinet.The receiver may conveniently be a U-tube which can be immersed in water.The outlet shall be open to the atmosphere to prevent
32、pressure build-up.Fumes are toxic and it is recommended that the process is carried out in a fume cupboard.The tar receiver should be cleared on a regular basis, by placing tar in a heat resistant crucible and burning off in a furnace.WARNING THE FUMES ARE TOXIC AND DUE CARE SHOULD BE EXERCISED IN T
33、HEIR DISPOSAL.6 Preparation of sampleThe coal used for the determination of the Gray-King coke type is the analysis sample ground to pass a sieve of 212 m aperture. If necessary, expose the sample in a thin layer for the minimum time required for the moisture content to reach approximate equilibrium
34、 with the laboratory atmosphere.Before commencing the determination, mix the air-dried sample thoroughly for at least 1 min, preferably by mechanical means. The sample shall be prepared on the same day as the determination is carried out.2 ISO 2015 All rights reservedBS ISO 502:2015ISO 502:2015(E)7
35、Procedure7.1 Coals with a Gray-King coke type within the range A to G2(see 10.3)Raise the temperature of the furnace until it is steady at 325 C.Weigh on a scoop 20,0 g 0,1g of the sample and transfer it to the retort tube (5.2), held in such a manner that the coal cannot enter the side arm. Complet
36、e the transfer with a soft brush and allow the coal to fall to the far end of the retort tube. Hold the tube horizontally, insert the distance rod (5.3) so that the face of the disk is 150 mm from the closed end of the retort tube and spread the coal into a layer of uniform depth by shaking and turn
37、ing. Withdraw the distance rod and insert a flattened pad of asbestos wool or a notched asbestos disk to retain the coal in position. Without disturbing the position of the coal, close the open end of the retort tube with a heat-resisting stopper. Connect the receiver (5.4) to the side arm and inser
38、t the retort tube in position in the furnace (5.1) so that the centre of the coal layer coincides with the centre of the furnace. If the furnace is mounted on rails, clamp the retort tube in a horizontal position and run the furnace into position.Raise the energy input to the furnace in such a manne
39、r that the temperature of 325 C is regained in 3 min to 7 min and maintain a uniform rate of rise of 5 C/min thereafter until a temperature of 590 C is reached. At this point, regulate the energy input to the furnace so that a temperature of 600 C is reached, and maintain this temperature for 15 min
40、.Withdraw the retort tube (or retract the furnace) and allow it to cool. Detach the receiver, remove the stopper and slide the coke residue out for examination.NOTE lf the coal has an ash greater than 10 %, the Gray-King result might be affected.7.2 Coals with a Gray-King coke type greater than G2(s
41、ee 10.3)Weigh X g of the electrode carbon (4.1), where X is always an integer, into a weighing bottle and add (20 X) g of the coal sample. Insert the stopper and mix the contents thoroughly.Transfer the mixture to the retort tube and proceed exactly as specified in 7.1.Repeat the determination if ne
42、cessary, varying the amount of electrode carbon in 20 g of the mixture, until a coke residue of type G is obtained using the minimum mass of electrode carbon.8 Expression of resultsReport the Gray-King coke type of a coal by reference to Figure 1 and Table 3, where the appearance of typical coke res
43、idues is described and illustrated. For coals giving a coke type with an index greater than G2, the subscript defines the minimum number of grams of electrode carbon added to produce a standard G type coke residue.9 Precision of the method9.1 GeneralTable 1Type of cokeMaximum acceptable difference b
44、etween resultsSame laboratory (Repeatability)Different laboratory (Reproducibility)A to G1Greater than G1One letter One unit in the subscriptOne letter One unit in the subscript ISO 2015 All rights reserved 3BS ISO 502:2015ISO 502:2015(E)9.2 RepeatabilityThe results of duplicate determinations, carr
45、ied out at different times in the same laboratory by the same operator using the same apparatus on the same analysis sample, shall not differ by more than the above value.9.3 ReproducibilityThe means of the results of duplicate determinations, carried out in each of two different laboratories on rep
46、resentative portions taken from the same analysis sample after the last stage of sample preparation, shall not differ by more than the above value.10 Notes on procedure10.1 It has been shown that anthracite may be used as an alternative to electrode carbon. Any material which has been found by exper
47、iment to produce results equivalent to those obtained when using standard electrode carbon may be used.If anthracite is to be used, it should meet the following parameters:Retained on 212 m test sieve nilThrough 212 m, retained on 125 m 5 % to 10 %Through 125 m, retained on 63 m 20 % to 25 %Through
48、63 m 65 % to 75 %10.2 Determine the true relative density using a density bottle (see ISO 1014). To ensure complete wetting of the electrode carbon, use a 1 % solution of a wetting agent and evacuate the density bottle containing the electrode carbon and wetting agent solution to a pressure of 8 kPa
49、1)in a vacuum desiccator. Maintain this vacuum for 10 min before transferring the density bottle to a water-bath thermostatically controlled at 25 C.10.3 Although there is no precise relationship between the crucible swelling number and the Gray-King coke type, the following table shows the broad relationship to be expected. This can be found useful for indicating the necessity for blending with electrode carbon and the probable amount required.Table 2Crucible swelling number Gray-King coke type0 to 1/2 A to
