1、Solid biofuels Sample preparationBS EN ISO 14780:2017BSI Standards PublicationWB11885_BSI_StandardCovs_2013_AW.indd 1 15/05/2013 15:06EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 14780 May 2017 ICS 75.160.40; 27.190 Supersedes EN 14780:2011English Version Solid biofuels - Sample preparat
2、ion (ISO 14780:2017) Biocombustibles solides - Prparation des chantillons (ISO 14780:2017) Biogene Festbrennstoffe - Probenherstellung (ISO 14780:2017) This European Standard was approved by CEN on 15 March 2017. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipula
3、te the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN member. This European Sta
4、ndard exists in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management Centre has the same status as the official versions. CEN members are the na
5、tional standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, S
6、erbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels 2017 CEN All rights of exploitation in any form and
7、by any means reserved worldwide for CEN national Members. Ref. No. EN ISO 14780:2017 ENational forewordThis British Standard is the UK implementation of EN ISO 14780:2017. It supersedes BS EN 14780:2011, which is withdrawn.The UK participation in its preparation was entrusted to Technical Committee
8、PTI/17, Solid biofuels.A list of organizations represented on this committee can 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. The British Standards Institution 2017
9、Published by BSI Standards Limited 2017ISBN 978 0 580 89836 5ICS 75.160.40; 27.190Compliance with a British Standard cannot confer immunity from legal obligations.This British Standard was published under the authority of the Standards Policy and Strategy Committee on 31 July 2017.Amendments/corrige
10、nda issued since publicationDate Text affectedBRITISH STANDARDBS EN ISO 14780:2017EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 14780 May 2017 ICS 75.160.40; 27.190 Supersedes EN 14780:2011English Version Solid biofuels - Sample preparation (ISO 14780:2017) Biocombustibles solides - Prpar
11、ation des chantillons (ISO 14780:2017) Biogene Festbrennstoffe - Probenherstellung (ISO 14780:2017) This European Standard was approved by CEN on 15 March 2017. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard
12、the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN member. This European Standard exists in three official versions (English, Fr
13、ench, German). A version in any other language made by translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management Centre has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Bulgari
14、a, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerlan
15、d, Turkey and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels 2017 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Mem
16、bers. Ref. No. EN ISO 14780:2017 EBS EN ISO 14780:2017EN ISO 14780:2017 (E) 2 European foreword This document (EN ISO 14780:2017) has been prepared by Technical Committee ISO/TC 238 “Solid biofuels“ in collaboration with Technical Committee CEN/TC 335 “Solid biofuels” the secretariat of which is hel
17、d by SIS. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by November 2017, and conflicting national standards shall be withdrawn at the latest by November 2017. Attention is drawn to the possibility
18、 that some of the elements of this document 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 EN 14780:2011. According to the CEN-CENELEC Internal Regulations, the national standards organizat
19、ions of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malt
20、a, Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. Endorsement notice The text of ISO 14780:2017 has been approved by CEN as EN ISO 14780:2017 without any modification. ISO 14780:2017(E)Foreword ivIntroduction v1
21、Scope . 12 Normative references 13 Terms and definitions . 14 Symbols 25 Principles of correct sample reduction 26 Apparatus . 26.1 Apparatus for sample division. 26.1.1 General 26.1.2 Riffle boxes 26.1.3 Rotary sample dividers 36.1.4 Shovels and scoops 46.2 Apparatus for particle size-reduction . 5
22、6.2.1 Coarse cutting mill or wood crusher 56.2.2 Cutting mill . 56.2.3 Axe 66.2.4 Hand saw 66.2.5 Sieves . 66.2.6 Balance . 67 Sample reduction General principles 68 Methods for sample division 88.1 General . 88.2 Riffling 98.3 Strip mixing 98.4 Long pile-alternate shovel method 98.5 Rotary divider
23、. 108.6 Coning and quartering . 108.7 Mass reducing straw-like material (handful sampling)109 Method for reducing laboratory samples to sub-samples and general analysis samples.119.1 Mixing 119.2 Initial sample division . 119.3 Pre-drying 119.4 Coarse cutting (particle size reduction to 100 mm mater
24、ial, e.g. wood logs or briquettesStraw-like material with a low bulk den-sity (BD 200 kg/m3) and lengths 31,5 mmIrregular/mixed materials, e.g. hogfuels, logging residues, barkMethod for determi-nation of minimum sample massCalculate the mini-mum sample mass according to Table 2Number of pieces shou
25、ld be stated, e.g. 10 pieces randomly collectedMinimum sample mass should be de-fined, e.g. 500 gTo be determined ac-cording to fuel type6 ISO 2017 All rights reservedBS EN ISO 14780:2017ISO 14780:2017(E)6.2.3 AxeAn axe is used for cutting wood logs or coarse material down to a maximum 30 mm thickne
26、ss or suitable size to be processed in a cutting mill provided with a 30 mm sieve.6.2.4 Hand sawA hand saw is used to saw off wood logs or coarse material down to a maximum 30 mm thickness or suitable size to be processed in a cutting mill provided with a 30 mm sieve.A chain saw may contaminate the
27、sample by chain oil and should therefore not be used. A saw machine should not be used for size reduction to avoid the risk of losing moisture in the sample as a result of heat caused by friction.6.2.5 SievesA wire-mesh sieve with an aperture size of 1 mm, in accordance with ISO 3310-1, is recommend
28、ed to check the nominal top size of general analysis samples. A wire-mesh sieve with an aperture size of 0,25 mm will be recommended if sub-samples with this nominal top size are required.6.2.6 BalanceA balance is required that is capable of determining the mass of samples to an accuracy of 0,1 % of
29、 the sample mass, and the mass of sub-samples to an accuracy of 0,1 % of the sub-sample mass.7 Sample reduction General principlesFor every sample division stage to be carried out, it is important that a sufficient mass of material is retained, otherwise the sub-samples produced or the test portions
30、 to be taken may not be representative of the original sample. Due to various shape and size of different solid biofuels, different methods for determination of minimum sample masses have to be applied. Table 2 gives a guideline for minimum masses to be retained after each sample division stage, dep
31、ending on the nominal top size of the material.Regarding pellets, the pellets diameter shall be considered the nominal top size and the opening of the equipment shall be large enough for the longest pellets to pass through.In addition to the minimum masses stated in Table 2, the mass after sample di
32、vision shall be sufficiently large for the actual test or tests to be performed. Table 1 gives a guideline for the selection of the method to be applied to determinate the minimum sample mass to be retained after each sample division stage. Supplementary requirements concerning the masses of the tes
33、t portions are given in international standards for test methods of solid biofuels.Table 1 Guideline to choose a method to determine the minimum masses to be retained during sample division stages1 2 3 4Material Bulk material of less than or equal to 100 mm nominal top size as defined in ISO 16559La
34、rge pieces 100 mm material, e.g. wood logs or briquettesStraw-like material with a low bulk den-sity (BD 200 kg/m3) and lengths 31,5 mmIrregular/mixed materials, e.g. hogfuels, logging residues, barkMethod for determi-nation of minimum sample massCalculate the mini-mum sample mass according to Table
35、 2Number of pieces should be stated, e.g. 10 pieces randomly collectedMinimum sample mass should be de-fined, e.g. 500 gTo be determined ac-cording to fuel type6 ISO 2017 All rights reserved ISO 14780:2017(E)Table 2 Guideline for minimum masses to be retained during sample division stages, applicabl
36、e for material according to column 1 in Table 1Nominal top size mmMinimum mass g100634531,51683,1510,2515 0004 0001 5005003502501003010According to particle size distribution, shape and density of particles, the calculation of minimum sample mass should be adapted to the methods given here at the be
37、st in practical terms.Figure 5 summarizes the range of steps that can be taken during sample reduction. ISO 2017 All rights reserved 7BS EN ISO 14780:2017ISO 14780:2017(E)NOTE List of optional sub-sample extractions can not be exhaustive.Figure 5 Flow sheet for sample preparation and optional extrac
38、tion of sub-samples8 Methods for sample division8.1 GeneralCombined samples may be divided into two or more laboratory samples and laboratory samples are in general further divided in sub-samples (test portions). This clause describes the methods and procedures for sample division. For every divisio
39、n step, the mass of retained material given in Table 2 shall be taken into account.8 ISO 2017 All rights reservedBS EN ISO 14780:2017ISO 14780:2017(E)NOTE List of optional sub-sample extractions can not be exhaustive.Figure 5 Flow sheet for sample preparation and optional extraction of sub-samples8
40、Methods for sample division8.1 GeneralCombined samples may be divided into two or more laboratory samples and laboratory samples are in general further divided in sub-samples (test portions). This clause describes the methods and procedures for sample division. For every division step, the mass of r
41、etained material given in Table 2 shall be taken into account.8 ISO 2017 All rights reserved ISO 14780:2017(E)8.2 RifflingThis may be used for materials that can be passed through the riffle without bridging. It is not suitable for straw, bark, or other materials containing elongated particles, or f
42、or wet and/or sticky materials. Brittle materials should be handled with care to avoid the production of fine materials. Place the whole of the combined sample into one of the containers of the riffle so that it is evenly distributed throughout the container. Place the other two containers in positi
43、on under the riffle. Pour the contents of the first container down the centre line of the riffle. Pour the biofuel sufficiently slowly to avoid bridging occurring. Do not move the container from side to side (this would cause the end slots to receive less biofuel). Discard the biofuel that falls int
44、o one of the containers, chosen at random. Repeat the riffling process until a sub-sample of the required mass is obtained. See Figure 1 for an example of a riffle box.8.3 Strip mixingThis may be used for all materials and will be a convenient method when a combined sample is to be divided into a sm
45、all number of laboratory samples. Place the whole combined sample on a clean, hard surface and homogenize it by mixing with a shovel, and form into a strip at least 20 times as long as it is wide. Distribute the sample along the length of the strip as evenly as possible, working randomly from end to
46、 end. Building up the strip with several layers will increase the quality of the division.Obtain a laboratory sample by taking at least 20 increments from locations evenly spaced along the length of the strip. Take each increment by inserting two plates vertically into the strip and removing all the
47、 material from between the plates. The two plates should be inserted the same distance apart each time so that each increment contains the same quantity of material. The distance between the plates should be at least 2,5 times the nominal top size and at least the length of normal oversized material
48、 particles. See Figure 6 for the principle of strip mixing.Figure 6 Strip mixingKey1 increment2 sampling frame3 end plates8.4 Long pile-alternate shovel methodThis sub-sampling method is recommended for the reduction of samples in excess of approximately 50 kg. Place the entire combined sample on a
49、clean and even floor and mix it thoroughly by manually moving the material to form a long pile. Carry out this process at least three times to ensure thorough mixing. When forming new piles, deposit each shovelful on the end of the new pile. Divide the last pile into two equal piles by using a shovel. Place alternate shovel loads to either side and form into two piles with at least 10 shovel loads (increments) in each pile. One pile is randomly selected and the process is repeated, using appropriately smaller increments as the piles
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