1、BRITISH STANDARDBS EN 14671:2006Characterization of sludges Pre-treatment for the determination of extractable ammonia using 2 mol/l potassium chlorideThe European Standard EN 14671:2006 has the status of a British StandardICS 13.030.20g49g50g3g38g50g51g60g44g49g42g3g58g44g55g43g50g56g55g3g37g54g44g
2、3g51g40g53g48g44g54g54g44g50g49g3g40g59g38g40g51g55g3g36g54g3g51g40g53g48g44g55g55g40g39g3g37g60g3g38g50g51g60g53g44g42g43g55g3g47g36g58BS EN 14671:2006This British Standard was published under the authority of the Standards Policy and Strategy Committee on 30 April 2007 BSI 2007ISBN 978 0 580 50513
3、 3National forewordThis British Standard was published by BSI. It is the UK implementation of EN 14671:2006.The UK participation in its preparation was entrusted to Technical Committee EH/5, Sludge characterization.A list of organizations represented on EH/5 can be obtained on request to its secreta
4、ry.The UK committee has never seen the need to standardize this method at a European level and, as a consequence, has not been actively involved in the development of this standard. However, the UK committee is pleased that a classic British method was selected. The method has long been used as a va
5、luable operational-control method and is available in existing technical literature (see reference 1 in the bibliography of this standard). Due to the difficulty and cost of sending liquid sludge samples (in such a manner that their properties do not change) to laboratories for international interla
6、boratory trials of the performance of this method, interested parties convened at a workshop to assess the test. Their conclusion was that the results are operationally defined (e.g. by the filter paper used) and, as the document does not specify all such operational details, the performance data ar
7、e not really applicable outside the context of the workshop. As a result, the members of EH/5 have no information to offer on the reproducibility of the results.This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application.
8、Compliance with a British Standard cannot confer immunity from legal obligations. Amendments issued since publicationAmd. No. Date CommentsEUROPEAN STANDARDNORME EUROPENNEEUROPISCHE NORMEN 14671June 2006ICS 13.030.20English VersionCharacterization of sludges - Pre-treatment for the determinationof e
9、xtractable ammonia using 2 mol/l potassium chlorideCaractrisation des boues - Prtraitement pour ladtermination de lAzote ammoniacal extractible utilisant2mol/l de chlorure de potassiumCharakterisierung von Schlmmen - Vorbehandlung zurBestimmung des extrahierbaren Ammoniums unterVerwendung von 2 mol/
10、l KaliumchloridThis European Standard was approved by CEN on 24 May 2006.CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this EuropeanStandard the status of a national standard without any alteration. Up-to-date lists and bibliograp
11、hical references concerning such nationalstandards 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 translationunder the responsibility of a CEN m
12、ember into its own language and notified to the Central Secretariat has the same status as the officialversions.CEN members are the national standards bodies of Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France,Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lith
13、uania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania,Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.EUROPEAN COMMITTEE FOR STANDARDIZATIONCOMIT EUROPEN DE NORMALISATIONEUROPISCHES KOMITEE FR NORMUNGManagement Centre: rue de Stassart, 36 B-1050 Brussels 2006 CEN
14、 All rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN 14671:2006: EEN 14671:2006 (E) 2 Contents Page Foreword3 Introduction .4 1 Scope 5 2 Normative references 5 3 Terms and definitions .5 4 Principle5 5 Limitations and interferences.5 6 Haza
15、rds .6 7 Reagents.6 8 Apparatus .6 9 Sample pre-treatment7 10 Procedure .7 11 Expression of results 8 12 Test report 8 Annex A (informative) Performance data of the interlaboratory comparison Summary of sludge exchangeable ammonia results.9 Bibliography. 11 EN 14671:2006 (E) 3 Foreword This document
16、 (EN 14671:2006) has been prepared by Technical Committee CEN/TC 308 “Characterization of sludges”, the secretariat of which is held by AFNOR. 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 Decem
17、ber 2006, and conflicting national standards shall be withdrawn at the latest by December 2006. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Cyprus, Czech Republic,
18、Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. EN 14671:2006 (E) 4 Introduction Because sludge may be applie
19、d to land as manure or as a disposal, there is a need to monitor extractable ammonia. EN 14671:2006 (E) 5 1 Scope This European standard specifies a procedure for the determination of extractable ammonia using a 2 mol/l potassium chloride solution in raw and digested sewage sludges. The range of the
20、 method is up to 100 g/kg N assuming appropriate dilution of the potassium chloride extract in the final measurement step. NOTE The above wording will be modified once the round robin results are available. It may be suitable for other types of sludges, but the user should validate the method using
21、these sludges. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. EN 12880:20
22、00, Characterization of sludges Determination of dry residue and water content EN ISO 3696:1995, Water for analytical laboratory use Specification and test methods (ISO 3696:1987) 3 Terms and definitions For the purposes of this European Standard, the following terms and definitions apply. 3.1 extra
23、ctable ammonia ammonia that is released when the homogenised sludge is shaken with 2 mol/l potassium chloride for 1 h at room temperature 3.2 dry residue dry mass portion of the sludge obtained after the specified drying process, expressed as a percentage EN 12880:2000, 3.1 4 Principle An aliquot of
24、 the homogenised sludge is shaken for 1 h with 2 mol/l potassium chloride at room temperature. The sample is then filtered and the ammonia determined by a suitable method. Potassium chloride (2 mol/l) is used rather than water to ensure that both soluble and ion exchangeable forms of the determinand
25、 are determined. It also minimises biological activity in the extracted sample. All results are expressed as nitrogen. Although undried samples are taken for analysis, it is recognised practice to report results on a dry weight basis. Consequently the dry residue content of the homogenised sample us
26、ed for analysis should also be determined using a separate test portion (see EN 12880). 5 Limitations and interferences Substances present at their normal concentration in these types of samples should not cause significant interference in the pre-extraction step. For the vast majority of sewage slu
27、dges, the relatively high concentration of ammonia compared with potential interferences should not result in any significant EN 14671:2006 (E) 6 interferences in the final measurement stage. The user should carry out suitable recovery checks to confirm this. 6 Hazards 6.1 General Waste and sludge s
28、amples may contain hazardous and inflammable substances. They may contain pathogens and be liable for biological action. Consequently it is recommended that these samples should be handled with special care. The gases, which may be produced by microbiological activity are potentially inflammable and
29、 will pressurise sealed bottles. Exploding bottles are likely to result in infectious shrapnel and/or pathogenic aerosols. Glass bottles should be avoided whenever possible. National regulations should be followed with respect to microbiological hazards associated with this method. NOTE All equipmen
30、t used in the vicinity should be flame proof to avoid any risk of ignition. 6.2 Storage It is not advisable to store samples in an open laboratory. If samples are to be stored, store them between 0 C and 4 C. Sample containers that enable the escape of any generated gas should be used. 7 Reagents 7.
31、1 Water complying with purity grade 2 of EN ISO 3696:1995 7.2 Potassium chloride c(KCl) = 2,5 mol/l Dissolve (931,9 1) g of potassium chloride (dried at (105 2) C for 1 h) in approximately 3 l of water and dilute to 5 l with water in a volumetric flask. 8 Apparatus Ordinary laboratory apparatus and
32、the following: 8.1 Extraction bottles Wide-necked glass or plastics bottles with secure stoppers or caps, for example 250 ml nominal capacity. 8.2 Mechanical shaking apparatus Any suitable horizontal or inversion shaker shall be used (e. g. horizontal shaker (20 rpm to 40 rpm with 20 mm throw); roll
33、er table rotating at about 10 rpm; end-over-end tumbler (5 rpm to 10 rpm). NOTE Other shaking devices may be used provided that they can be shown to provide equivalent results. The material being leached should not settle or be agitated too vigorously so that particle abrasion occurs. 8.3 Balance wi
34、th on accuracy 0,05 g. 8.4 Drying oven, capable of maintained at (105 5) C 8.5 Suitable apparatus for the determination of ammonia in diluted sludge filtrates (See 10.4). EN 14671:2006 (E) 7 8.6 Filter papers Cellulose filter papers with a pore size of 20 to 25 . (For example Whatman 5411). 9 Sample
35、 pre-treatment 9.1 Sample preservation Sludge samples can change composition through biological and/or chemical activity. They shall be kept in cool boxes at less than 4 C in transit to the laboratory. They shall be analysed as soon as possible (within 24 h) after sampling. If prolonged storage is u
36、navoidable, then store the samples at or below a temperature of 18 C in a freezer for a maximum period of 4 weeks and note this on the test report. 9.2 Preparation of sample The purpose of pre-treatment is to obtain a representative and homogeneous sample. Samples shall not be subject to any drying
37、prior to homogenisation because this will result in a loss of ammonia. For frozen samples see NOTE below. NOTE For frozen sludges, it is recommended that a suitable aliquot (equivalent to 0,25 g to 1 g of dry matter) of the frozen homogenised sample is directly transferred to the potassium chloride
38、solution, as transformation of nitrogen compounds can occur during the thawing process. 10 Procedure 10.1 Transfer a known weight (m gram) of suitably homogenised (as sampled) sludge (equivalent to (0,25 to 1) g 2 mg of dry matter, see NOTES 1 and 2) to an extraction bottle (8.1). Add (80 1) ml 2,5
39、mol/l potassium chloride (7.2) and (20 m) 1 ml of water (7.1) (See also 9.2, NOTE). NOTE 1 If a dry solids result is not available and an immediate analysis is required, then visually estimate the dry solids content. NOTE 2 The maximum “as received” weight of sludge taken should not exceed 20 g. 10.
40、2 Replace the bottle cap and place on a shaker for (60 5) min at room temperature (see 8.2). 10.3 Owing to the difficulty in filtering many types of sludge samples, it is recommended that a suitable aliquot of the leached sample is centrifuged. Then filter a suitable volume aliquot through a fluted
41、filter paper (8.6) discarding at least the first 10 ml. In some cases paper filtration is too slow or even impossible. In such cases a validated alternative procedures for obtaining a clear supernatant are acceptable and the technique used shall be reported. The filtrate is stable for some hours in
42、a hermetically closed polyethylene bottle if stored in a refrigerator at (0 to 4) C. The filtrate can be stored for longer periods in a deep freezer at less than -18 C. NOTE Vacuum filtration should not be used as it can result in loss of ammonia. In most instances the ammonia concentration will be
43、sufficiently high to dilute the leached sample extract 10 times prior to this filtration step. This will greatly aid the speed of the filtration step. This dilution must be 1) This information is given for the convenience of users of this European Standard and does not constitute an endorsement by C
44、EN of the product named. Equivalent products may be used if they can be shown to lead to the same results. EN 14671:2006 (E) 8 accounted for in the final calculation and the calibration standards need to be made up in 0,2 mol/l KCl rather than 2 mol/l KCl. 10.4 Analyse the ammonia according to ISO 5
45、664, EN ISO 11732 or EN ISO 14911 or equivalent validated method within one day unless stored at less than 18 C (4 weeks). 10.5 A reagent blank without the addition of any sludge shall be taken throughout the whole procedure. 10.6 It is important to ensure that the calibration standards and blank sh
46、all be prepared in 2 mol/l potassium chloride (Add 80 ml of reagent 7.2, (2,5 mol/l KCl) per 100 ml). 11 Expression of results 11.1 Calculation The extractable ammonia content, EAis expressed in g of nitrogen, N per kg dry mass and is given by equation (1): ()drbA10 wmVCCE= (1) where C is the ammoni
47、um nitrogen concentration in the extract, in mg/l ; Cbis the ammonium nitrogen concentration in the reagent blank, in mg/l ; m is the wet mass of sample taken for extraction, in g; wdris the dry residue of the sludge determined by method EN 12880, in %; V is the total volume of the extractant used,
48、in ml (100 ml) 11.2 Precision See Annex A. 12 Test report The test report shall contain the following information: a) reference to this European Standard; b) all information necessary for the complete identification of the sludge sample; c) details of sample pre-treatment, if carried out; d) results
49、 of the determination according to Clauses 10 and 11; e) any detail not specified in this European Standard and any other factor which may have affected the results. EN 14671:2006 (E) 9 Annex A (informative) Performance data of the interlaboratory comparison Summary of sludge exchangeable ammonia results Due to difficulties examining sludge samples for its ammonia contents following regular interlaboratory comparisons (distribution of sub-samples to a number of participating laboratories), it was decided to follow the instructi
