BS EN ISO 9408-1999 Water quality - Evaluation of ultimate aerobic biodegradability of organic compounds in aqueous medium by determination of oxygen demand in a closed respiromete.pdf

1、BRITISH STANDARD BS EN ISO 9408:1999 BS 6068-5.11:1999 Water quality Evaluation of ultimate aerobic biodegradability of organic compounds in aqueous medium by determination of oxygen demand in a closed respirometer The European Standard EN ISO 9408:1999 has the status of a British Standard ICS 07.10

2、0.20; 13.060.70BSENISO9408:1999 This British Standard, having been prepared under the directionof the Health andEnvironment Sector Committee,was published underthe authority of theStandards Committee andcomes into effect on 15 October 1999 BSI 04-2000 ISBN 0 580 35102 5 National foreword This Britis

3、h Standard is the English language version of EN ISO9408:1999. Itis identical with ISO9408:1999. It supersedes BS EN29408:1993 which is withdrawn. The UK participation in its preparation was entrusted by Technical CommitteeEH/3, Water quality, to Subcommittee EH/3/5, Biological methods, which has th

4、e responsibility to: aid enquirers to understand the text; present to the responsible international/European committee any enquiries on the interpretation, or proposals for change, and keep the UKinterests informed; monitor related international and European developments and promulgate them in the U

5、K. A list of organizations represented on this subcommittee can be obtained on request to its secretary. Cross-references Attention is drawn to the fact that CEN and CENELEC Standards normally include an annex which lists normative references to international publications with their corresponding Eu

6、ropean publications. The British Standards which implement these international or European publications referred to in this document may be found in the BSI Standards Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Find” facility of the BSI Stand

7、ards Electronic Catalogue. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Summary of pag

8、es This document comprises a front cover, an inside front cover, pagesi andii, theENISO title page, page2, the ISO title page, pagesii toiv, pages1 to12, an inside back cover and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be

9、indicated in the amendment table on the inside front cover. Amendments issued since publication Amd. No. Date CommentsBSENISO9408:1999 BSI 04-2000 i Contents Page National foreword Inside front cover Foreword 2 Foreword iii Text of ISO 9408 1ii blankEUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM

10、EN ISO 9408 August 1999 ICS 13.060.00 Supersedes EN 29408:1993 English version Water quality Evaluation of ultimate aerobic biodegradability of organic compounds in aqueous medium by determination of oxygen demand in a closed respirometer (ISO9408:1999) Qualit de leau Evaluation de la biodgradabilit

11、 arobie ultime des compossorganiques, en milieu aqueux, pardtermination de la demande en oxygne dans un respiromtre ferm (ISO 9408:1999) Wasserbeschaffenheit Bestimmung der vollstndigen aeroben biologischen Abbaubarkeit organischer Stoffe im wrigen Medium ber die Bestimmung desSauerstoffbedarfs in e

12、inem geschlossenenRespirometer (ISO 9408:1999) This European Standard was approved by CEN on 1 August 1999. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alterat

13、ion. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the Central Secretariat or to any CEN member. This European Standard exists in three official versions (English, French, German). A version in any other language made by translat

14、ion under the responsibility of a CEN member into its own language and notified to the Central Secretariat has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, CzechRepublic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Ital

15、y, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. CEN European Committee for Standardization Comit Europen de Normalisation Europisches Komitee fr Normung Central Secretariat: rue de Stassart 36, B-1050 Brussels 1999 CEN All rights of exploitation in any fo

16、rm and by any means reserved worldwide for CEN national Members. Ref. No. EN ISO 9408:1999 EENISO9408:1999 BSI 04-2000 2 Foreword The text of the International Standard ISO9408:1999 has been prepared by Technical Committee ISO/TC147 “Water quality” in collaboration with Technical Committee CEN/TC230

17、 “Water analysis”, the secretariat of which is held by DIN. This European Standard supersedes EN29408:1993. 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 February2000, and conflicting national s

18、tandards shall be withdrawn at the latest by February2000. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, CzechRepublic, Denmark, Finland, France, Germany, Greece, Ice

19、land, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and the United Kingdom. NOTE FROM CEN/CS: The foreword is susceptible to be amended on reception of the German language version. The confirmed or amended foreword, and when appropriate, the normative Annex ZA

20、 for the references to international publications with their relevant European publications will be circulated with the German version. Endorsement notice The text of the International Standard ISO9408:1999 was approved by CEN as a European Standard without any modification.ENISO9408:1999 ii BSI 04-

21、2000 Contents Page Foreword iii 1 Scope 1 2 Terms and definitions 1 3 Principle 2 4 Test environment 2 5 Reagents 2 6 Apparatus 3 7 Procedure 3 8 Calculation and expression of results 6 9 Validity of results 7 10 Test report 7 Annex A (informative) Example of calculation of theoretical oxygen demand

22、 9 Annex B (informative) Correction of oxygen uptake for interference by nitrification 10 Annex C (informative) Example of a biodegradation curve 11 Annex D (informative) Closed respirometer 12 Bibliography Inside back cover Figure C.1 Biodegradation of aniline in the respirometric test 11 Figure D.

23、1 Principle of a closed respirometer 12 Table 1 Final distribution of test and reference compounds in the test vessels 5ENISO9408:1999 BSI 04-2000 iii Foreword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The wor

24、k of preparing International 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-governme

25、ntal, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization. International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part3. Draft

26、International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an International Standard requires approval by at least75% of the member bodies casting a vote. International Standard ISO9408 was prepared by Technical Committee ISO/TC147, Wat

27、er quality, Subcommittee SC5, Biological methods. This second edition cancels and replaces the first edition (ISO9408:1991), which has been technically revised. Annex A to Annex D of this International Standard are for information only.iv blankENISO9408:1999 BSI 04-2000 1 WARNING Activated sludge an

28、d sewage contain potentially pathogenic organisms. Take appropriate precautions when handling them. Handle with care toxic test compounds and those whose properties are unknown. 1 Scope This International Standard specifies a method, by determination of the oxygen demand in a closed respirometer, fo

29、r the evaluation in aqueous medium of the ultimate biodegradability of organic compounds and waste waters at a given concentration by aerobic microorganisms. The method applies to organic compounds which a) are water-soluble under the conditions of the test; b) are poorly water-soluble under the con

30、ditions of the test, in which case special measures may be necessary to achieve good dispersion of the compound (see for example, ISO10634); c) do not reach and react with the CO 2absorbent; d) are volatile, provided that a suitable respirometer or suitable conditions (e.g.a smaller ratio of volume

31、head space to volume liquid medium) are used; e) are not inhibitory to the test microorganisms at the concentration chosen for the test. The presence of inhibitory effects can be determined as specified in7.3, or by using any other method for determining the inhibitory effect of a compound on bacter

32、ia (see, for example, ISO8192). NOTEThe conditions described in this International Standard do not always correspond to the optimal conditions for allowing the maximum degree of biodegradation to occur. For alternative biodegradation methods, see ISO15462. 2 Terms and definitions For the purposes of

33、 this International Standard, the following terms and definitions apply. 2.1 ultimate aerobic biodegradation breakdown of a chemical compound or organic matter by microorganisms in the presence of oxygen to carbon dioxide, water and mineral salts of any other elements present (mineralization) and th

34、e production of new biomass 2.2 primary biodegradation structural change (transformation) of a chemical compound by microorganisms, resulting in the loss of a specific property 2.3 activated sludge biomass produced in the aerobic treatment of wastewater by the growth of bacteria and other microorgan

35、isms in the presence of dissolved oxygen 2.4 concentration of suspended solids of an activated sludge amount of solids obtained by filtration or centrifugation of a known volume of activated sludge and drying at about105 C to constant mass 2.5 biochemical oxygen demand BOD mass concentration of diss

36、olved oxygen consumed under specified conditions by the aerobic biological oxidation of a chemical compound or organic matter in water NOTEIt is expressed in this case as milligrams oxygen uptake per milligram (or gram) test compound. 2.6 chemical oxygen demand COD mass concentration of oxygen equiv

37、alent to the amount of a specified oxidant consumed by a chemical compound or organic matter when a water sample is treated with that oxidant under defined conditions NOTEIt is expressed in this case as milligrams oxygen consumed per milligram (or gram) test compound. 2.7 theoretical oxygen demand T

38、hOD theoretical maximum amount of oxygen required to oxidize a chemical compound completely, calculated from the molecular formula NOTEIt is expressed in this case as milligrams oxygen required per milligram (or gram) test compound. 2.8 dissolved organic carbon DOC that part of the organic carbon in

39、 the water which cannot be removed by specified phase separation NOTEExamples of specified phase separation are centrifugation at40000 ms 2for15min or by membrane filtration using membranes with pores of0,24m to0,454m diameter. 2.9 lag phase time from the start of a test until adaptation and/or sele

40、ction of the degrading microorganisms are achieved and the biodegradation degree of a chemical compound or organic matter has increased to about10% of the maximum level of biodegradationENISO9408:1999 2 BSI 04-2000 NOTEIt is expressed in days. 2.10 maximum level of biodegradation maximum biodegradat

41、ion degree of a chemical compound or organic matter in a test, above which no further biodegradation takes place during the test NOTEIt is expressed in percent. 2.11 biodegradation phase time from the end of the lag phase of a test until about90% of the maximum level of biodegradation has been reach

42、ed NOTEIt is expressed in days. 2.12 plateau phase time from the end of the biodegradation phase until the end of the test NOTEIt is expressed in days. 2.13 pre-exposure pre-incubation of an inoculum in the presence of the test chemical compound or organic matter, with the aim of enhancing the abili

43、ty of this inoculum to biodegrade the test material by adaptation and/or selection of the microorganisms 2.14 preconditioning pre-incubation of an inoculum under the conditions of the subsequent test in the absence of the test chemical compound or organic matter, with the aim of improving the perfor

44、mance of the test by acclimatization of the microorganisms to the test conditions 3 Principle Determination of the biodegradation of organic compounds by aerobic microorganisms is carried out using a static aqueous test system. Organic compounds in the context of this International Standard include

45、waste waters. The test mixture contains an inorganic medium, the organic compound as the sole source of carbon and energy at a mass concentration of normally100mg/l organic carbon but its theoretical oxygen demand (ThOD) shall be at least100mg/l, and a mixed inoculum obtained from a waste-water trea

46、tment plant or from another source in the environment. The mixture is agitated in a closed test vessel and the consumption of oxygen is determined either by measuring the amount of oxygen required to maintain a constant gas volume in the respirometer vessel, or by measuring the change in volume or p

47、ressure (or a combination of the two) in the apparatus. The evolved carbon dioxide is absorbed in a suitable substance in the test vessel. The degradation is followed over a period of28d, or longer if necessary, by determining the consumption of oxygen either automatically or manually. The amount of

48、 oxygen consumed by the organic compound (after correction by comparison with blank control) is expressed as a percentage of either the theoretical oxygen demand (ThOD), calculated from the formula of the compound, or the chemical oxygen demand (COD). For sufficiently water-soluble compounds, remova

49、l of dissolved organic carbon (DOC) may be determined (optionally) by measuring the concentration of DOC at the beginning and the end of incubation to obtain additional information on the ultimate biodegradability. If a substance-specific analytical method is available, information on the primary degradability may be obtained. 4 Test environment Incubation shall take place in the dark or in diffused light, at a temperature within the range20 C to25 C which shall not vary by more than 1 C during the test. 5 Reagents Use only r