1、Solid Biofuels SamplingBS EN ISO 18135:2017BSI Standards PublicationWB11885_BSI_StandardCovs_2013_AW.indd 1 15/05/2013 15:06National forewordThis British Standard is the UK implementation of EN ISO 18135:2017. It is identical to ISO 18135:2017. It supersedes BS EN 14778:2011, which is withdrawn.The
2、UK participation in its preparation was entrusted to Technical Committee 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 respons
3、ible for its correct application. The British Standards Institution 2017 Published by BSI Standards Limited 2017ISBN 978 0 580 89837 2ICS 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 S
4、tandards Policy and Strategy Committee on 30 June 2017.Amendments/corrigenda issued since publicationDate Text affectedBRITISH STANDARDBS EN ISO 18135:2017EUROPEAN STANDARDNORME EUROPENNEEUROPISCHE NORMEN ISO 18135April 2017ICS 75.160.40 Supersedes EN 14778:2011EUROPEAN COMMITTEE FOR STANDARDIZATION
5、COMIT EUROPEN DE NORMALISATIONEUROPISCHES KOMITEE FR NORMUNGCEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels 2017 CEN Ref. No. EN ISO 18135:2017: EAll rights of exploitation in any form and by any means reserved worldwide for CEN national MembersSolid Biofuels - Sampling (ISO 18135:2
6、017) Biocarburants solides - chantillonnage (ISO 18135:2017) Biogene Festbrennstoffe - Probenahme (ISO 18135:2017) This European Standard was approved by CEN on 6 March 2017.CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this Europ
7、ean 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 Standard exists in three official versions
8、(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 national standards bodies of Austria, Belgi
9、um, 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, Serbia, Slovakia, Slovenia, Spain, Sweden,
10、 Switzerland, Turkey and United Kingdom.English VersionEN ISO 18135:2017 (E)European forewordThis document (EN ISO 18135:2017) 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 held b
11、y 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 October 2017 and conflicting national standards shall be withdrawn at the latest by October 2017.Attention is drawn to the possibility that so
12、me 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 ISO 14778:2011.This document has been prepared under a mandate given to CENELEC by the European Commissi
13、on and the European Free Trade Association.According to the CEN-CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former
14、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, Switzerland, Turkey and the United Kingdom.Endorsement noticeThe text of ISO 181
15、35:2017 has been approved by CEN as EN ISO 18135:2017 without any modification.iiBS EN ISO 18135:2017ISO 18135:2017(E)Foreword vIntroduction vi1 Scope . 12 Normative references 13 Terms and definitions . 14 Symbols 25 Principle 36 Establishing a sampling scheme (sampling plan) 46.1 Principle 46.2 Fu
16、ll sampling plan 56.3 Brief sampling plan . 56.4 Division of lots . 57 Visual inspection 68 Number of increments 68.1 General . 68.2 Primary increment variance (Vi) . 78.3 Preparation and testing variance (VPT) . 88.4 Overall precision (PL) 88.5 Calculation of number of increments per (sub-) lot . 8
17、9 Calculation of the size of increment 1010 Combined sample Calculation of the volume of the combined sample .1011 Sampling equipment .1011.1 General 1011.2 Equipment for manual sampling 1111.2.1 Sampling box for falling-stream 1111.2.2 Scoops 1211.2.3 Shovels . 1311.2.4 Forks 1411.2.5 Grabs . 1511.
18、2.6 Probes (thieves).1611.2.7 Pipes (spears) 1611.2.8 Frames . 1711.2.9 Hooks 1711.2.10 Drills (augers) . 1811.3 Equipment for mechanical sampling 1911.3.1 Use of coal sampling standards and checking for bias .1911.3.2 Falling-stream sampler .1911.3.3 Cross-belt sampler 2011.3.4 Mechanical probes .2
19、111.3.5 Mechanical drills .2112 Sampling in practice 2112.1 General 2112.2 Methods for sampling stationary material 2212.2.1 Sampling from small packages (40 t3.3nominal top sizeaperture size of the sieve through which at least 95 % by mass of the material passesNote 1 to entry: For pellets the diam
20、eter is used to determine the nominal top size.Note 2 to entry: Includes additional information not found in ISO 16559.3.4overall precisioncloseness of agreement between independent test results obtained under stipulated conditions; including sample preparation and sample analysisNote 1 to entry: A
21、determination might be made with great precision and the standard deviation of a number of determinations on the same sub-lot might, therefore, be low; but such results are accurate only if they are free from bias.4 Symbolsd95nominal top size biofuel, in mmdidifference between individual pair member
22、smlotmass of the lot or sub-lot, tonnen number of increments per (sub-) lotnminminimum number of increments per (sub-) lotnPnumber of pairs (for estimating VPT)nmpmaximum practicable number of increments per sub-lotNL, NSLnumber of lots/sub-lotsPLoverall precision for the sampling, sample preparatio
23、n and testing for the whole biofuel lot at 95 % confidence levelPSLsimilar to PLbut then for the sub-lotS sample estimate of the population standard deviationVSPTtotal variance of the results for replicate samplesVolCombined Samplevolume for the combined sample, lVolincrvolume of an increment, lVolm
24、inminimum volume of increment, lViprimary increment variance2 ISO 2017 All rights reservedBS EN ISO 18135:2017ISO 18135:2017(E)VPTpreparation and testing varianceW width of a sampling tool, mmXivalue of the analyzed parameter5 PrincipleThe main principle of correct sampling is to obtain a representa
25、tive sample (samples) from the whole lot concerned. Every particle in the lot or sub-lot to be represented by the sample should have an equal probability of being included in the sample. In order to do so, a sampling plan is needed. Figure 1 shows the actions needed for the development of a sampling
26、 plan. When sampling is to be carried out according to the same plan repeatedly or continuously (e.g. daily), a full sampling plan shall be prepared according to 6.2 (it is necessary to do this only once). A brief sampling plan shall be prepared for routine use according to 6.3 (same type of samplin
27、g object or situation occasionally). In the case of a new material or supplier, the existing plan shall be checked and updated or a new full sampling plan shall be developed. ISO 2017 All rights reserved 3BS EN ISO 18135:2017ISO 18135:2017(E)Figure 1 Procedure for samplingNOTE The numbers in Figure
28、1 refer to the clauses in this document.6 Establishing a sampling scheme (sampling plan)6.1 PrincipleThe sampler shall prepare a full sampling plan either by copying the forms presented in Annex A or by preparing his own forms or documents containing the appropriate items selected from those shown i
29、n Annex A. Each sampling plan shall be given a unique reference number or a code/name.4 ISO 2017 All rights reservedBS EN ISO 18135:2017ISO 18135:2017(E)6.2 Full sampling planA Model Sampling Plan is presented in Annex A as forms that are to be completed by the sampler. Once completed, these forms b
30、ecome sampling certificates.6.3 Brief sampling planThe sampling plan shall include the following key elements:a) reference to the full sampling plan (Annex A);b) unique identification number of the sample;c) date and time of sampling;d) identity of the biofuel supplier;e) identification number of th
31、e lot or the sub-lot;f) type of biofuel (wood pellet, briquette, chips, etc.).Also consider including the following items:g) name of the sampler;h) mass or volume of the sub-lot or the lot;i) identity of the carrier (transport company);j) storage information of the lot (like weather conditions, stor
32、age inside or outside);k) sampling technique, e.g. shovelling, cross stream cutter, hammer sampler, probe, stopped belt, etc.;l) any other details that change from sample to sample;m) source (pile, silo, cargo hold, train car, truck/lorry, etc.) and location (centre, bottom, etc.) where the sample w
33、as obtained.6.4 Division of lotsThe lot may be sampled as a whole, resulting in one sample, or divided into a number of sub-lots resulting in a possible sample from each. In the case of manual sampling a lot may be sampled as a whole only when it has a maximum of 2 500 t or as a series of sub-lots e
34、ach to a maximum of 2 500 t, e.g. fuel dispatched or delivered over a period of time, a ship load, a train load, a wagon load, or fuel produced during a certain period, e.g. a shift.Such division into a number of sub-lots can be necessary toa) achieve the required precision (calculated by the proced
35、ure in 8.2),b) maintain the integrity of the sample by enclosing in an airtight plastic bag or container, e.g. avoiding bias that can result from the loss of moisture due to standing or changing of calorific value caused by biological activity,c) create convenience when sampling lots over a long per
36、iod, e.g. on a shift basis,d) keep sample masses manageable, taking into account the maximum lifting capacity,e) distinguish different components of a mixture of fuels, e.g. different biofuel types within one lot, andf) be consistent in sampling from several specified locations of the lot to avoid b
37、ias from particle segregation during loading. ISO 2017 All rights reserved 5BS EN ISO 18135:2017ISO 18135:2017(E)In the case of mechanical sampling, e.g. from large shipments, the maximum (sub-) lot size should be decided by the parties involved. For example, a maximum 5 000 t sub-lot is advisable.E
38、XAMPLE 1 Consider a power station that receives 140 lorry-loads of wood chips a month totalling 3 500 t. In this example, four sub-lots can be manually sampled where a sub-lot could be the quantity of fuel delivered in a week (about 35 lorry-loads).EXAMPLE 2 Consider a single shipment of 46 000 t of
39、 wood pellets. In this example, 10 sub-lots of 4 600 t each can be mechanically sampled or 19 sub-lot samples, each representing 2 421 t, would need to be taken manually.7 Visual inspectionVisual inspection shall be used for the choice or verification of the classification of the solid biofuels. Bas
40、ed on the sampling plan, verification or selection of the sampling equipment and the sampling method shall also be made by visual inspection. If the biofuel consists of a mixture of substantially different materials, or if it contains impurities (such as soil or pieces of metal), this shall be repor
41、ted in the sampling certificate. If the biofuel type or its quality is diverging strongly from the one expected, the sampler shall report without any delay to the appropriate party for further instructions.NOTE Photographs of deviation noted during visual inspection can assist with documentation.8 N
42、umber of increments8.1 GeneralIn all methods of sampling, sampling preparation and analysis, errors are incurred and the experimental results obtained from such methods for any given parameter deviate from the true value of that parameter. As the true value cannot be known exactly, it is not possibl
43、e to assess the accuracy of the experimental results, i.e. the closeness with which they agree with the true value. However, it is possible to make an estimate of the precision of the experimental results, i.e. the closeness with which the results of a series of experiments made on the same fuel, ag
44、ree among themselves.It is possible to design a sampling scheme that, in principle, can achieve a desired level of precision with a material determined lower limit.Precision is the closeness of agreement between the results obtained by applying the experimental procedure several times under prescrib
45、ed conditions, and is a characteristic of the sampling scheme used and the variability of the biofuel being sampled. The smaller the random errors of the scheme, the more precise the scheme is. A commonly accepted index of precision is two times the sample estimate of the population standard deviati
46、on, and this index of precision is used throughout this document.If a large number of replicate samples are taken from a sub-lot of biofuel, prepared and analyzed separately, the precision of a single observation, P, is given by Formula (1):Ps V=22SPT(1)wheres is the sample estimate of the populatio
47、n standard deviation;VSPTis the total variance of the results for replicate samples.6 ISO 2017 All rights reservedBS EN ISO 18135:2017ISO 18135:2017(E)Here VSPTis given by Formula (2):VVNnVNSPTSLPTSLi=+ (2)Therefore, the final overall precision, PL, for the total quantity of biofuel:PVNnVNLSLPTSLi=+
48、2 (3)wherePLis the overall precision for the sampling, sample preparation and testing for the whole biofuel lot at 95 % confidence level;Viis the primary increment variance;n is the number of increments per (sub-) lot;NSLis the number of sub-lots in the lot;VPTis the sample preparation and testing v
49、ariance.In the case where the total quantity of biofuel is divided into sub-lots, all sub-lots shall be sampled. The number of sub-lots can be 1.8.2 Primary increment variance (Vi)The primary increment variance, Vi, depends upon the type and nominal top size of the fuel, the degree of pre-treatment and mixing, the absolute value of the parameter to be determined and the mass of increment taken. In general, the increment variance (Vi) is different for the different parameters (in the same material) in practice. The calculation of the minimum number of incr
