1、BS ISO 13909-3:2016Hard coal and coke Mechanical samplingPart 3: Coal Sampling from stationarylotsBSI Standards PublicationWB11885_BSI_StandardCovs_2013_AW.indd 1 15/05/2013 15:06BS ISO 13909-3:2016 BRITISH STANDARDNational forewordThis British Standard is the UK implementation of ISO 13909-3:2016.I
2、t supersedes BS ISO 13909-3:2001 which is withdrawn.The UK participation in its preparation was entrusted to TechnicalCommittee PTI/16, Solid mineral fuels.A list of organizations represented on this committee can beobtained on request to its secretary.This publication does not purport to include al
3、l the necessaryprovisions of a contract. Users are responsible for its correctapplication. The British Standards Institution 2016.Published by BSI Standards Limited 2016ISBN 978 0 580 83176 8ICS 73.040Compliance with a British Standard cannot confer immunity fromlegal obligations.This British Standa
4、rd was published under the authority of theStandards Policy and Strategy Committee on 30 June 2016.Amendments/corrigenda issued since publicationDate T e x t a f f e c t e dBS ISO 13909-3:2016 ISO 2016Hard coal and coke Mechanical sampling Part 3: Coal Sampling from stationary lotsHouille et coke ch
5、antillonnage mcanique Partie 3: Charbon chantillonnage sur lots statiquesINTERNATIONAL STANDARDISO13909-3Second edition2016-07-01Reference numberISO 13909-3:2016(E)BS ISO 13909-3:2016ISO 13909-3:2016(E)ii ISO 2016 All rights reservedCOPYRIGHT PROTECTED DOCUMENT ISO 2016, Published in SwitzerlandAll
6、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 written permission. Permission can be requested fro
7、m 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 13909-3:2016ISO 13909-3:2016(E)Foreword iv1 Scope . 12 No
8、rmative references 13 Terms and definitions . 14 Establishing a sampling scheme 14.1 General . 14.2 Design of the sampling scheme 24.2.1 Material to be sampled . 24.2.2 Division of lots . 24.2.3 Precision of sampling . 24.2.4 Bias of sampling 34.3 Precision of results 34.3.1 Precision and total vari
9、ance . 34.3.2 Primary increment variance 44.3.3 Preparation and testing variance 44.3.4 Number of sub-lots and number of increments per sub-lot 44.4 Minimum mass of sample 64.5 Mass of primary increment 84.6 Size analysis . 95 Methods of sampling from wagons, barges and ships 105.1 General 105.2 Num
10、ber of increments and sub-lots 105.2.1 General analysis and moisture samples 105.2.2 Common sample 105.3 Taking the increments . 115.4 Distribution of increments 115.4.1 Wagons 115.4.2 Barges . 115.4.3 Ships 115.4.4 Random selection of increments. 116 Methods of sampling from stockpiles 127 Sampling
11、 equipment mechanical auger 138 Handling and storage of samples .159 Sample preparation 1610 Minimization of bias 1610.1 Causes of bias 1610.2 Checking for precision and bias 1611 Verification 17Bibliography .18 ISO 2016 All rights reserved iiiContents PageBS ISO 13909-3:2016ISO 13909-3:2016(E)Forew
12、ordISO (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 subject for which a technic
13、al 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) on all matters of el
14、ectrotechnical 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 of ISO documents should be noted. This document was
15、 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 held responsible for identifying any or all such paten
16、t 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 given for the convenience of users and does not co
17、nstitute 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 following URL: Foreword - Supplementary informationThe
18、 committee responsible for this document is ISO/TC 27, Solid mineral fuels, Subcommittee SC 4, Sampling.This second edition cancels and replaces the first edition (ISO 13909-3:2001), which has been technically revised.ISO 13909 consists of the following parts, under the general title Hard coal and c
19、oke Mechanical sampling: Part 1: General introduction Part 2: Coal Sampling from moving streams Part 3: Coal Sampling from stationary lots Part 4: Coal Preparation of test samples Part 5: Coke Sampling from moving streams Part 6: Coke Preparation of test samples Part 7: Methods for determining the p
20、recision of sampling, sample preparation and testing Part 8: Methods of testing for biasiv ISO 2016 All rights reservedBS ISO 13909-3:2016INTERNATIONAL STANDARD ISO 13909-3:2016(E)Hard coal and coke Mechanical sampling Part 3: Coal Sampling from stationary lots1 ScopeThis part of ISO 13909 specifies
21、 procedures for the mechanical sampling of coal from stationary lots, for example, from wagons, barges, ships and stockpiles. These procedures are to be used when it is not possible to sample the lots during loading or discharge according to ISO 13909-2. Procedures for sample preparation are given i
22、n ISO 13909-4.This part of ISO 13909 is applicable to mechanical sampling from stationary coal lots, to obtain samples from which test samples for the determination of moisture, and for general analysis including physical and chemical tests, can be prepared in accordance with the requirements and re
23、commendations set out in ISO 13909-4.In this part of ISO 13909, the principles and procedures for designing a sampling scheme are given, together with typical examples of applications; in addition, practices for the execution of sampling in different sampling situations are described. The methods de
24、scribed are limited to those on which it is possible to conduct a test for bias.2 Normative referencesThe following referenced documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies.
25、For undated references, the latest edition of the referenced document (including any amendments) applies.ISO 13909-1, Hard coal and coke Mechanical sampling Part 1: General introductionISO 13909-2, Hard coal and coke Mechanical sampling Part 2: Coal Sampling from moving streamsISO 13909-4, Hard coal
26、 and coke Mechanical sampling Part 4: Coal Preparation of test samplesISO 13909-7, Hard coal and coke Mechanical sampling Part 7: Methods for determining the precision of sampling, sample preparation and testingISO 13909-8, Hard coal and coke Mechanical sampling Part 8: Methods of testing for bias3
27、Terms and definitionsFor the purposes of this document, the terms and definitions given in ISO 13909-1 apply.4 Establishing a sampling scheme4.1 GeneralThe general procedure for establishing a sampling scheme is as follows.a) Define the quality parameters to be determined and the types of samples re
28、quired.b) Define the lot. ISO 2016 All rights reserved 1BS ISO 13909-3:2016ISO 13909-3:2016(E)c) Define or assume the precision required (see 4.3.1).d) Determine the method of combining the increments into samples and the method of sample preparation (see ISO 13909-4).e) Determine or assume the vari
29、ability of the coal (see 4.3.2) and the variance of preparation and testing (see 4.3.3). Methods for determining variability and variance of preparation and testing are given in ISO 13909-7.f) Establish the number of sub-lots and the number of increments per sub-lot required to attain the desired pr
30、ecision (see 4.3.4).g) Decide upon the sampling interval, in tonnes.h) Ascertain the nominal top size of coal for the purpose of determining the minimum mass of sample (see 4.4 and Table 1).The nominal top size may initially be ascertained by consulting the consignment details, or by visual estimati
31、on, and may be verified, if necessary, by preliminary test work.i) Determine the minimum average increment mass (see 4.5).4.2 Design of the sampling scheme4.2.1 Material to be sampledThe first stage in the design of the scheme is to identify the coal to be sampled. Samples may be required for techni
32、cal evaluation, process control, quality control and for commercial reasons by both the producer and the customer. It is essential to ascertain exactly at what stage in the coal-handling process the sample is required and, as far as practicable, to design the scheme accordingly. In some instances, h
33、owever, it may prove impracticable to obtain samples at the preferred points and, in such cases, a more practicable alternative is required.4.2.2 Division of lotsA lot may be sampled as a whole or as a series of sub-lots, e.g. coal despatched or delivered over a period of time, a ship load, a train
34、load, a wagon load or coal produced in a certain period (e.g. a shift).It may be necessary to divide a lot into a number of sub-lots in order to improve the precision of the results.For lots sampled over long periods, it may be expedient to divide the lot into a series of sub-lots, obtaining a sampl
35、e for each.4.2.3 Precision of samplingAfter the desired sample precision has been selected, the number of sub-lots and the minimum number of increments per sub-lot collected shall be determined as described in 4.3.4, and the average mass of the primary increments shall be determined as described in
36、4.5.For single lots, the quality variation shall be assumed as the worst case (see 4.3.2 and 4.3.3). The precision of sampling achieved may be measured using the procedure of replicate sampling (see ISO 13909-7).At the start of regular sampling of unknown coals, the worst-case quality variation shal
37、l be assumed, in accordance with 4.3.2, 4.3.3 and 4.3.4. When sampling is in operation, a check may be carried out to confirm that the desired precision has been achieved, using the procedures described in ISO 13909-7.If any subsequent change in precision is required, the number of sub-lots and of i
38、ncrements shall be changed as determined in 4.3.4 and the precision attained shall be rechecked. The precision shall also 2 ISO 2016 All rights reservedBS ISO 13909-3:2016ISO 13909-3:2016(E)be checked if there is any reason to suppose that the variability of the coal being sampled has increased. The
39、 number of increments determined in 4.3.4 applies to the precision of the result when the sampling errors are large relative to the testing errors, e.g. for moisture content.4.2.4 Bias of samplingIt is of particular importance in sampling to ensure, as far as possible, that the parameter to be measu
40、red is not altered by the sampling and sample preparation process or by subsequent storage prior to testing. This may require, in some circumstances, a limit on the minimum mass of primary increment (see 4.5).When collecting samples for moisture determination from lots over an extended period, it ma
41、y be necessary to limit the standing time of samples by dividing the lot into a number of sub-lots (see 4.3.4.1).When a coal sampling scheme is implemented, it shall be checked for bias in accordance with the methods given in ISO 13909-8.4.3 Precision of results4.3.1 Precision and total varianceIn a
42、ll methods of sampling, sample preparation and analysis, errors are incurred and the experimental results obtained from such methods for any given parameter will deviate from the true value of that parameter. While the absolute deviation of a single result from the “true” value cannot be determined,
43、 it is possible to make an estimate of the precision of the experimental results. This is the closeness with which the results of a series of measurements made on the same coal agree among themselves.It is possible to design a sampling scheme by which, in principle, an arbitrary level of precision c
44、an be achieved.The required overall precision for a lot is normally agreed between the parties concerned. In the absence of such agreement, a value of one tenth of the ash content may be assumed up to 10 % ash, subject to a maximum of 1 % absolute for ash contents above 10 %.The theory of the estima
45、tion of precision is discussed in ISO 13909-7. The following formula is derived:PVnVmLIPT=+2 (1)wherePLis the estimated index of overall precision of sampling, sample preparation and testing for the lot at a 95 % confidence level, expressed as percentage absolute;VIis the primary increment variance;
46、n is the number of increments per sub-lot;m is the number of sub-lots in the lot;VPTis the preparation and testing variance.If the quality of a coal of a type not previously sampled is required, then in order to devise a sampling scheme, assumptions have to be made about the variability (see 4.3.2).
47、 The precision actually achieved for a particular lot by the scheme devised can be measured by the procedures given in ISO 13909-7. ISO 2016 All rights reserved 3BS ISO 13909-3:2016ISO 13909-3:2016(E)4.3.2 Primary increment varianceThe primary increment variance, VI, depends upon the type and nomina
48、l top size of coal, the degree of pre-treatment and mixing, the absolute value of the parameter to be determined and the mass of increment taken.The number of increments required for the general-analysis sample and the moisture sample shall be calculated separately using the relevant values of incre
49、ment variance and the desired precision. If a common sample is required, the number of increments required for that sample shall be the greater of the numbers calculated for the general analysis sample and the moisture sample respectively.NOTE For many coals, the increment variance for ash is higher than that for moisture and hence, for the same precision, the number of increments required for the general analysis sample will be adequate for the moisture sample and for the common sample.The value
