1、BSI Standards PublicationBS ISO 18871:2015Method of determiningcoalbed methane contentBS ISO 18871:2015 BRITISH STANDARDNational forewordThis British Standard is the UK implementation of ISO 18871:2015.The UK participation in its preparation was entrusted to Technical Committee PTI/15, Natural Gas a
2、nd Gas Analysis.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 2015. Publis
3、hed by BSI Standards Limited 2015ISBN 978 0 580 86768 2 ICS 73.020 Compliance 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 October 2015.Amendments issued since public
4、ationDate T e x t a f f e c t e dBS ISO 18871:2015 ISO 2015Method of determining coalbed methane contentMthode de dosage de la teneur en mthane de houilleINTERNATIONAL STANDARDISO18871First edition2015-09-15Reference numberISO 18871:2015(E)BS ISO 18871:2015ISO 18871:2015(E)ii ISO 2015 All rights res
5、ervedCOPYRIGHT PROTECTED 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 int
6、ranet, without prior 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
7、.iso.orgBS ISO 18871:2015ISO 18871:2015(E)Foreword v1 Scope . 12 Terms and definitions . 13 Apparatus . 33.1 Desorption canister 33.2 Metering device 33.3 Thermostat . 53.4 Temperature measuring devices . 53.5 Barometer . 53.6 Electronic balance (top load) . 53.7 Standard sieve . 53.8 Coal crusher .
8、 53.9 Hose 63.10 Gas-sample bottles 63.11 Padding 63.12 Quick connector . 63.13 Gas analyser . 64 Sample collection . 74.1 Preparation of sampling . 74.1.1 General 74.1.2 Desorption canister . 74.1.3 Metering device. 74.1.4 Thermostat . 74.2 Sampling principle . 74.2.1 Sample quality . 74.2.2 Sampli
9、ng time . 84.3 Sampling procedure . 84.3.1 General 84.3.2 Core samples . 84.3.3 Cutting samples 84.4 Coal lump samples . 84.4.1 General 84.4.2 Parameters to record . 85 Measuring method and process 95.1 Use of core samples . 95.1.1 Natural desorption . 95.1.2 Measurement of residual gas . 105.1.3 Ga
10、s sampling, composition analysis and isotope analysis 105.2 Use of cuttings samples or coal lump samples . 125.2.1 Q2 measurement .125.2.2 Q3 measurement .126 Data processing 136.1 Conversion of the desorbed gas volume 136.2 Reporting of gas content 136.3 Calculation of gas composition 136.4 Calcula
11、tion of gas content . 136.4.1 General. 136.4.2 Calculation of lost gas content (Q1) .136.4.3 Calculation of gas desorption content (Q2) .156.4.4 Calculation of residual gas content (Q3) 156.4.5 Calculation of free gas content 166.4.6 Calculation of gas content . 16 ISO 2015 All rights reserved iiiCo
12、ntents PageBS ISO 18871:2015ISO 18871:2015(E)6.4.7 Calculation of adsorption time . 176.5 Numerical accuracy requirements 177 Measurement report .178 Quality commentaries .178.1 Quality commentary of sample collection 178.1.1 Situations should be noted on the record .178.2 Quality commentary on meas
13、uring operation .188.3 Conclusion of quality commentary . 188.3.1 Qualified samples .188.3.2 Reference samples .188.3.3 Discard . 18Annex A (normative) Raw data of gas natural desorption 19Annex B (normative) Lost gas original records table.21Annex C (normative) Lost gas volume calculation of Sample
14、 XX (direct method) .22Annex D (normative) Cumulative gas desorption curve of sample XX .23Annex E (normative) Measurement results table of CBM content 24Annex F (normative) Sampling form for in-seam drilling .25Annex G (normative) Sampling form for core drilling 26Annex H (normative) Laboratory tes
15、t form27Annex I (normative) Short report .28Bibliography .29iv ISO 2015 All rights reservedBS ISO 18871:2015ISO 18871:2015(E)ForewordISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing Internationa
16、l Standards is normally carried out through ISO technical committees. Each member 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,
17、also take part in the work. ISO collaborates closely with the International Electrotechnical 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
18、. In particular the different approval criteria needed for the different types of ISO documents should be noted. This document was drafted in accordance with the editorial rules of the ISO/IEC Directives, Part 2. www.iso.org/directivesAttention is drawn to the possibility that some of the elements o
19、f this document may be the subject of patent rights. ISO shall not be held 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. www
20、.iso.org/patentsAny trade name used in this document is information 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 W
21、TO principles in the Technical Barriers to Trade (TBT), see the following URL: Foreword - Supplementary informationThe committee responsible for this document is ISO/TC 263, Coalbed methane (CBM). ISO 2015 All rights reserved vBS ISO 18871:2015BS ISO 18871:2015Method of determining coalbed methane c
22、ontent1 ScopeThis International standard provides methodology for measuring coalbed methane content of coal core samples obtained by coring or sidewall coring during well drilling. This standard has to be also applied to drill cuttings samples, if the equipment for the determination of the coalbed m
23、ethane content according to a respective national standard is not available. The selection of the most appropriate method shall consider the purpose of the test and the possibilities of sampling.This International standard is applicable for the direct method of measuring coalbed methane content. It
24、includes sample preparation, experimental procedures and calculation methods. Indirect methods of measuring gas content of coal (not included in this International standard) are generally based on either the gas sorption characteristics of coal under defined/specified pressure and temperature condit
25、ions.This International standard includes three types of direct measuring methods: conventional desorption (slow desorption) of core samples, fast desorption of core samples, fast desorption of cuttings or lump samples. The difference among them lies in the time allowed for gas to desorb before fina
26、l crushing and in sample size and shape.This International standard is applicable for the determination of the methane content of coal during coal and coalbed methane exploration for the determination of free gas content of low rank coals is included.Procedure of free gas content determination of lo
27、w rank coals need to be defined.All units used and referred to in this International standard are international standard units. Reference temperature is 0 C (273,15 K) if not stated differently. Reference pressure is 0,1 MPa (1 bar) if not stated differently.This International standard does not poin
28、t out all the potential safety hazards associated with its use. The users are responsible for establishing appropriate safety measures and health practices when applying the procedures defined in this standard.2 Terms and definitionsFor the purposes of this document, the following terms and definiti
29、ons apply.2.1coalbed gas contentunder natural conditions, quantity of gas contained in the unit mass of coalNote 1 to entry: It is the sum of lost gas, measurable gas and residual gas.2.2coalbed methane contentmethane content, which is commonly the major component of coalbed gasNote 1 to entry: The
30、terms “coalbed methane”, “coalbed gas” and “coal seam gas” are frequently used synonymously.Note 2 to entry: If a component other than methane is the predominant component of coalbed gas this should be stated explicitly.INTERNATIONAL STANDARD ISO 18871:2015(E) ISO 2015 All rights reserved 1BS ISO 18
31、871:2015ISO 18871:2015(E)2.3Q1 (lost gas)gas lost from the samples subsequent to its removal from its in situ position and prior to its containment in the canister, expressed as volume (at standard conditions) per unit mass of coal2.4Q2 (measurable gas)measurable gas desorbed at atmospheric pressure
32、 from the non-pulverized coal sample, expressed as the quantity per unit mass of coal2.5Q3 (residual gas)gas still contained in the coal sample before its pulverisation, expressed as the quantity per unit mass of coal2.6conventional desorption (slow desorption)method of gas determination in which vo
33、lumetric readings of canister gas content are taken frequently (every 5 min) during the first few (2 to 6) h, followed by hourly measurements for several hours, and then measurements on 24-h intervals until no or very little gas is being desorbed for an extended period of time2.7fast desorptionmetho
34、d of gas content determination in which a trend of gas desorbing from the coal sample is not establishedNote 1 to entry: Measurements are taken over a period of time typically less than 1 day2.8samplingactivity that take some representative part of coal from coalbed2.9core samplecylindrical section
35、of rock (coal) that is usually 5 cm to 10 cm in diameter taken as part of the interval penetrated by a core bit and brought to the surface for geological examination, representative sampling, and laboratory analysis2.10cuttings samplerock (coal) fragments, chips, particles with a size of typically 5
36、 mm that break off because of the action of the drill bit and are transported to the surface by the drilling circulation system2.11coal lump samplescoal fragments or pieces of coal fragments that break off in the extraction or development process of a coal mine operation, from coal transport or stor
37、age or by manual removal from the coal seam or an intact core sample. The size is larger than that of cuttings and smaller than the inner diameter of the canister used for transportation and desorption2.12low-rank coalthe coal and rock thermal evolution degree is low, vitrinite of oil-immersed maxim
38、um reflectance Rv,max 0,65%, including lignite and long flame coalSOURCE: ISO 11760:20052.13high-rank coalscoal and rock thermal evolution degree is high, vitrinite of oil-immersed average random reflectance Rr 2,0%, including anthracite coal2 ISO 2015 All rights reservedBS ISO 18871:2015ISO 18871:2
39、015(E)3 Apparatus3.1 Desorption canisterThe desorption canister is a sealable container into which the coal samples are placed to determine their gas content. The canister should be designed such that the coal can be transferred into a pressure-tight status as quickly as possible.Canisters should be
40、 easy to handle and fill and should close rapidly to form a gas sealed space.The material of the canister shall not absorb coalbed gas, or react with drilling fluid and coalbed gas. Therefore, it is recommended to use aluminium alloy, coated aluminium, PVC and/or stainless steel materials.When using
41、 core samples, the canister volume shall be more than 1 000cm3with a suitable inner diameter. It should maintain gas tightness up to a pressure of 0,3 MPa.When using cuttings samples or coal lump samples, the canister volume shall be 500 cm3. The ratio of canister volume and sample volume shall be b
42、etween 70 and 150. The desorption canister shall be equipped with a shut-off valve and a rubber hose to connect it to a gas metering device and gas analyser (Figure 1).Key1 squeezing device2 desorption canister3 hose4 flowmeter5 gas analyserFigure 1 Desorption canister with connection to gas analyse
43、r3.2 Metering deviceThe measurement of desorbed gas volumes shall be executed either by the displacement of water (displacement method) or by flushing the crusher head with a defined volume of air and subsequent analysis of the gas composition (flushing method).For the displacement method, a graduat
44、ed measuring cylinder (burette) is used. The volume and scale of the measuring cylinder shall be appropriate to the desorption volume. The measuring cylinder and storage reservoir are preferably of glass. Readings of the gas volume are taken at atmospheric pressure by adjusting the liquid levels in
45、the tube and the storage cup. The minimum graduation on the metering scale shall be no more than 10 cm3. The measuring cylinder is connected at the bottom to a storage ISO 2015 All rights reserved 3BS ISO 18871:2015ISO 18871:2015(E)reservoir and at the top to the desorption canister head. The connec
46、tions shall be made of flexible and gas-tight plastic or rubber.Key1 desorption canister2 hose3 graduated cylinderFigure 2 Desorption canister with graduated cylinder for collection of desorbed gasKey1 desorption canister2 hose3 burette4 storage reservoirFigure 3 Desorption canister with graduated b
47、urette and storage reservoir for pressure equilibration4 ISO 2015 All rights reservedBS ISO 18871:2015ISO 18871:2015(E)For the flushing method, a defined volume of air is passed through the crusher headspace and collected in a vessel, preferably of glass. The collecting vessel shall be connected to
48、the gas analyser see 3.13 by a flexible hose. The connections shall be flexible and gas tight plastic or rubber.3.3 ThermostatA water, oil or air thermostat shall be used with a temperature stability and controlling accuracy of 1C.3.4 Temperature measuring devicesTemperature should be measured with
49、an accuracy of 1C or better. The temperature range of the measuring devices (thermometer, thermocouple, resistance thermometer) should cover both the ambient temperature and the temperature in the thermostat holding the desorption canisters. Typically this should correspond to a range from 10 C to 80 C.3.5 BarometerThe measurement range of the barometer for metering the ambient pressure should cover the local range of ambient pressure. Scale intervals should be 0,1 kPa.3.6 Electronic balance (top load)A precision (accuracy 1 %) el
