1、BS ISO 14853:2016Plastics Determinationof the ultimate anaerobicbiodegradation of plasticmaterials in an aqueous system Method by measurement ofbiogas productionBSI Standards PublicationWB11885_BSI_StandardCovs_2013_AW.indd 1 15/05/2013 15:06BS ISO 14853:2016 BRITISH STANDARDNational forewordThis Br
2、itish Standard is the UK implementation of ISO 14853:2016.It supersedes BS ISO 14853:2005 which is withdrawn.The UK participation in its preparation was entrusted to TechnicalCommittee PRI/21, Testing of plastics.A list of organizations represented on this committee can beobtained on request to its
3、secretary.This publication does not purport to include all 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 89878 5ICS 83.080.01Compliance with a British Standard cann
4、ot confer immunity fromlegal obligations.This British Standard was published under the authority of theStandards Policy and Strategy Committee on 31 July 2016.Amendments/corrigenda issued since publicationDate T e x t a f f e c t e dBS ISO 14853:2016 ISO 2016Plastics Determination of the ultimate an
5、aerobic biodegradation of plastic materials in an aqueous system Method by measurement of biogas productionPlastiques valuation de la biodgradabilit anarobie ultime des matriaux plastiques en milieu aqueux Mthode par dtermination de la production de biogazINTERNATIONAL STANDARDISO14853Second edition
6、2016-07-15Reference numberISO 14853:2016(E)BS ISO 14853:2016ISO 14853:2016(E)ii ISO 2016 All rights reservedCOPYRIGHT PROTECTED DOCUMENT ISO 2016, Published in SwitzerlandAll rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form
7、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 from either ISO at the address below or ISOs member body in the country of the requester.ISO copyright officeCh. de Blandonnet 8
8、 CP 401CH-1214 Vernier, Geneva, SwitzerlandTel. +41 22 749 01 11Fax +41 22 749 09 47copyrightiso.orgwww.iso.orgBS ISO 14853:2016ISO 14853:2016(E)Foreword vIntroduction vi1 Scope . 12 Normative references 13 Terms and definitions . 14 Principle 35 Reagents and materials . 36 Apparatus . 56.1 Laborato
9、ry equipment . 56.2 Apparatus for use when biogas is measured by a manometric method . 66.3 Apparatus for use when biogas is measured by a volumetric method . 67 Procedure. 67.1 General . 67.2 Digested sludge . 67.3 Preparation of the inoculum . 77.4 Preparation of test suspensions and controls 77.5
10、 Incubation and gas measurement 87.6 Test duration . 97.7 Measurement of inorganic carbon . 97.8 Specific analyses 98 Calculation and expression of results . 98.1 Amount of carbon in headspace . 98.2 Calculation of amount of carbon in headspace when manometric measurement method is used . 108.3 Calc
11、ulation of amount of carbon in headspace when volumetric measurement method is used . 118.4 Amount of inorganic carbon in the liquid . 118.5 Total amount of carbon converted to gas 118.6 Amount of carbon in test material 128.7 Calculation of percentage biodegradation . 129 Validity of results 129.1
12、Maintenance of anaerobic conditions 129.2 Inhibition of degradation 129.3 Validity of the test 1210 Test report 13Annex A (informative) Example of apparatus for determining the amount of biogas produced by measuring the increase in gas pressure 14Annex B (informative) Example of apparatus for determ
13、ining volumetrically the amount of biogas produced .15Annex C (informative) Example of a biodegradation curve .17Annex D (informative) Examples of data sheets for anaerobic biodegradability tests .18Annex E (informative) Table of water vapour pressures at various temperatures .21Annex F (informative
14、) Calculation of theoretical carbon dioxide (ThCO2) and theoretical methane (ThCH4) production 22Annex G (informative) Example of determination of recovery rate 23Annex H (informative) Example of a workflow scheme .26 ISO 2016 All rights reserved iiiContents PageBS ISO 14853:2016ISO 14853:2016(E)Bib
15、liography .28iv ISO 2016 All rights reservedBS ISO 14853:2016ISO 14853:2016(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
16、 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, also take part in the work. ISO collaborates cl
17、osely 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. In particular the different approval criteria
18、 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 (see www.iso.org/directives).Attention is drawn to the possibility that some of the elements of this document may be the subject of pat
19、ent 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 (see www.iso.org/patents).Any trade name used
20、 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 World Trade Organization (WTO) princ
21、iples in the Technical Barriers to Trade (TBT) see the following URL: www.iso.org/iso/foreword.html.The committee responsible for this document is ISO/TC 61, Plastics, Subcommittee SC 5, Physical-chemical properties.This second edition cancels and replaces the first edition (ISO 14853:2005), which h
22、as been technically revised. It also incorporates the Technical Corrigendum ISO 14853:2005/Cor.1:2009. ISO 2016 All rights reserved vBS ISO 14853:2016ISO 14853:2016(E)IntroductionWith the increasing use of plastics, their recovery and disposal have become a major issue. As a first priority, recovery
23、 should be promoted. For example, plastic litter, which originates mainly from consumers, is difficult to recover completely. Additional examples of materials difficult to recover are found in the disposal of fishing tackle, agricultural mulch films and water-soluble polymers. These plastic material
24、s tend to leak from closed waste management infrastructures into natural environments. Biodegradable plastics are now emerging as one of the available options to solve such environmental issues. Plastic materials, such as products or packaging, which are sent to anaerobic treatment facilities should
25、 be potentially biodegradable. Therefore, it is very important to determine the potential biodegradability of such materials and to obtain a quantitative measure of their biodegradability in anaerobic environments.vi ISO 2016 All rights reservedBS ISO 14853:2016Plastics Determination of the ultimate
26、 anaerobic biodegradation of plastic materials in an aqueous system Method by measurement of biogas productionWARNING Sewage and activated sludge may contain potentially pathogenic organisms. Therefore, appropriate precautions should be taken when handling them. Digesting sewage sludge produces flam
27、mable gases which present fire and explosion risks. Care should be taken when transporting and storing quantities of digesting sludge. Toxic test chemicals and those whose properties are not known should be handled with care and in accordance with safety instructions. The pressure meter and microsyr
28、inges should be handled carefully to avoid needle stick injuries. Contaminated syringe needles should be disposed of in a safe manner.1 ScopeThis International Standard specifies a method for the determination of the ultimate anaerobic biodegradability of plastics by anaerobic microorganisms. The co
29、nditions described in this International Standard do not necessarily correspond to the optimum conditions for the maximum degree of biodegradation to occur. The test calls for exposure of the test material to sludge for a period of up to 90 d, which is longer than the normal sludge retention time (2
30、5 to 30 d) in anaerobic digesters, although digesters at industrial sites can have much longer retention times.The method applies to the following materials: natural and/or synthetic polymers, copolymers or mixtures thereof; plastic materials which contain additives such as plasticizers, colorants o
31、r other compounds; water-soluble polymers; materials which, under the test conditions, do not inhibit the microorganisms present in the inoculum. Inhibitory effects can be determined using an inhibition control or by another appropriate method (see e.g. ISO 13641). If the test material is inhibitory
32、 to the inoculum, a lower test concentration, another inoculum or a pre-exposed inoculum can be used.2 Normative referencesThere are no normative references in this document.3 Terms and definitionsFor the purposes of this document, the following terms and definitions apply.3.1ultimate anaerobic biod
33、egradationbreakdown of an organic compound by microorganisms in the absence of oxygen to carbon dioxide, methane, water and mineral salts of any other elements present (mineralization) plus new biomass3.2primary anaerobic biodegradationstructural change (transformation) of a chemical compound by mic
34、roorganisms, resulting in the loss of a specific propertyINTERNATIONAL STANDARD ISO 14853:2016(E) ISO 2016 All rights reserved 1BS ISO 14853:2016ISO 14853:2016(E)3.3digested sludgemixture of settled sewage and activated sludge which have been incubated in an anaerobic digester at about 35 C to reduc
35、e the biomass and odour and to improve the dewaterability of the sludgeNote 1 to entry: Digested sludge contains an association of anaerobic fermentative and methanogenic bacteria producing carbon dioxide and methane.3.4concentration of suspended solids in digested sludgeamount of solids obtained by
36、 filtration or centrifugation of a known volume of activated sludge and drying at about 105 C to constant mass3.5dissolved organic carbonDOCorganic carbon in the water phase which cannot be removed by specified phase separation, for example, by centrifugation at 40 000 ms2for 15 min or by membrane f
37、iltration using membranes with pores of 0,2 m to 0,45 m diameter3.6inorganic carbonICinorganic carbon which is dissolved or dispersed in the aqueous phase of a liquid and is recoverable from the supernatant liquid after the sludge has been allowed to settle3.7total dry solidsamount of solids obtaine
38、d by taking a known volume of test material or inoculum and drying at about 105 C to constant mass3.8theoretical amount of evolved biogasThbiogasmaximum theoretical amount of biogas (CH4+ CO2) evolved after complete biodegradation of an organic material under anaerobic conditions, calculated from th
39、e molecular formula and expressed as millilitres of biogas evolved per milligram of test material under standard conditions3.9theoretical amount of evolved carbon dioxideThCO2maximum theoretical amount of carbon dioxide evolved after complete oxidation of an organic material, calculated from the mol
40、ecular formula and expressed as milligrams of carbon dioxide per milligram of test material3.10theoretical amount of evolved methaneThCH4maximum theoretical amount of methane evolved after complete reduction of an organic material, calculated from the molecular formula and expressed as milligrams of
41、 methane evolved per milligram of test material3.11lag phaselag periodtime, measured in days, from the start of a test until adaptation and/or selection of the degrading microorganisms is achieved and the degree of biodegradation of a chemical compound or organic matter has increased to about 10 % o
42、f the maximum level of biodegradation2 ISO 2016 All rights reservedBS ISO 14853:2016ISO 14853:2016(E)3.12plateau phasetime, measured in days, from the end of the biodegradation phase until the end of the test3.13biodegradation phasetime, measured in days, from the end of the lag phase of a test unti
43、l about 90 % of the maximum level of biodegradation has been reached3.14maximum level of biodegradationdegree of biodegradation, measured in percent, of a chemical compound or organic matter in a test, above which no further biodegradation takes place during the test4 PrincipleThe biodegradability o
44、f a plastic material is determined using anaerobic conditions in an aqueous system. Test material with a concentration of 20 mg/l to 200 mg/l organic carbon (OC) is incubated at (35 2) C in sealed vessels together with digested sludge for a period normally not exceeding 90 d. Before use, the digeste
45、d sludge is washed so that it contains very low amounts of inorganic carbon (IC) and diluted to 1 g/l to 3 g/l total solids concentration. The increase in headspace pressure or the volumetric increase (depending on the method used for measuring biogas evolution) in the test vessels resulting from th
46、e production of carbon dioxide (CO2) and methane (CH4) is measured. A considerable amount of CO2will be dissolved in water or transformed to bicarbonate or carbonate under the conditions of the test. This inorganic carbon (IC) is measured at the end of the test. The amount of microbiologically produ
47、ced biogas carbon is calculated from the net biogas production and the net IC formation in excess of blank values. The percentage biodegradation is calculated from the total amount of carbon transformed to biogas and IC and the measured or calculated amount of carbon added as test material. The cour
48、se of biodegradation can be followed by making intermediate measurements of biogas production. As additional information, the primary biodegradability can be determined by specific analyses at the beginning and end of the test.This test method is designed to determine the biodegradability of plastic
49、 materials under anaerobic conditions. Optionally, the assessment of the recovery rate may also be of interest (see Annex G).5 Reagents and materials5.1 Distilled or deionized water, free of toxic substances, containing less than 2 mg/l of DOC.5.2 Test medium, prepared using only reagents of recognized analytical grade.Prepare the test medium to contain the following constituents in the stated amounts:Anhydrous potassium dihydrogen phosphate KH2PO40,27 gDisodium hydrogen phosphate dodecahydrate Na2HPO412H2O 1,12 gAmmoniu
