1、November 2012 Translation by DIN-Sprachendienst.English price group 9No part of this translation may be reproduced without prior permission ofDIN Deutsches Institut fr Normung e. V., Berlin. Beuth Verlag GmbH, 10772 Berlin, Germany,has the exclusive right of sale for German Standards (DIN-Normen).IC
2、S 13.080.10; 13.030.01!$B,“1923109www.din.deDDIN EN 16169Sludge, treated biowaste and soil Determination of Kjeldahl nitrogen;English version EN 16169:2012,English translation of DIN EN 16169:2012-11Schlamm, behandelter Bioabfall und Boden Bestimmung des Kjeldahl-Stickstoffs;Englische Fassung EN 161
3、69:2012,Englische bersetzung von DIN EN 16169:2012-11Boues, bio-dchets traits et sols Dtermination de lazote Kjeldahl;Version anglaise EN 16169:2012,Traduction anglaise de DIN EN 16169:2012-11www.beuth.deDocument comprises 16 pagesIn case of doubt, the German-language original shall be considered au
4、thoritative.10.12 DIN EN 16169:2012-11 2 A comma is used as the decimal marker. National foreword This standard has been prepared by Technical Committee CEN/TC 400 “Project Committee Horizontal standards in the fields of sludge, biowaste and soil” (Secretariat: DIN, Germany). The responsible German
5、body involved in its preparation was the Normenausschuss Wasserwesen (WaterPractice Standards Committee), Working Committee NA 119-01-02 Abfall- und BodenuntersuchungNA119-01-02-02 AA Chemische und physikalische Verfahren. ,The DIN Standards corresponding to the International Standards referred to i
6、n this document are as follows: ISO 5725-2 DIN ISO 5725-2 ISO 11261 DIN ISO 11261 ISO 11465 DIN ISO 11465 ISO 18512 DIN ISO 18512 DIN EN 16169:2012-11 3 National Annex NA (informative) Bibliography DIN ISO 5725-2, Accuracy (trueness and precision) of measurement methods and results Part 2: Basic met
7、hod for the determination of repeatability and reproducibility of a standard measurement method DIN ISO 11261, Soil quality Determination of total nitrogen Modified Kjeldahl method DIN ISO 11465, Soil quality Determination of dry matter and water content on a mass basis Gravimetric method DIN ISO 18
8、512, Soil quality Guidance on long and short term storage of soil samples DIN EN 16169:2012-11 4 This page is intentionally blank EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 16169 August 2012 ICS 13.030.01; 13.080.10 English Version Sludge, treated biowaste and soil Determination of Kjeldah
9、l nitrogen Boues, bio-dchets traits et sols Dtermination de lazote Kjeldahl Schlamm, behandelter Bioabfall und Boden Bestimmung des Kjeldahl-Stickstoffs This European Standard was approved by CEN on 24 May 2012. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulat
10、e the conditions for giving this European 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 Stan
11、dard exists in three official versions (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 nat
12、ional standards bodies of Austria, Belgium, 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, Sl
13、ovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Management Centre: Avenue Marnix 17, B-1000 Brussels 2012 CEN All rights of exploitation in any form and by any means reserved
14、 worldwide for CEN national Members. Ref. No. EN 16169:2012: E EN 16169:2012 (E) 2 Contents PageForeword 3Introduction .41 Scope 52 Normative references 53 Terms and definitions .54 Principle 55 Interferences and sources of errors 66 Reagents .67 Apparatus .78 Sample storage and sample pretreatment
15、79 Procedure .79.1 General 79.2 Digestion .79.3 Titration .89.4 Performance check 89.5 Blank test 810 Calculation 811 Expression of results 912 Precision .913 Test report 9Annex A (informative) Repeatability and reproducibility data . 10A.1 Materials used in the interlaboratory comparison study . 10
16、A.2 Interlaboratory comparison results 11Bibliography . 12DIN EN 16169:2012-11EN 16169:2012 (E) 3 Foreword This document (EN 16169:2012) has been prepared by Technical Committee CEN/TC 400 “Project Committee - Horizontal standards in the fields of sludge, biowaste and soil”, the secretariat of which
17、 is held by DIN. 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 February 2013, and conflicting national standards shall be withdrawn at the latest by February 2013. Attention is drawn to the poss
18、ibility that some 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 has been prepared under a mandate given to CEN by the European Commission and the European Free Trade
19、Association. The preparation of this document by CEN is based on a mandate by the European Commission (Mandate M/330), which assigned the development of standards on sampling and analytical methods for hygienic and biological parameters as well as inorganic and organic determinants, aiming to make t
20、hese standards applicable to sludge, treated biowaste and soil as far as this is technically feasible. 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
21、, 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, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the
22、United Kingdom. DIN EN 16169:2012-11EN 16169:2012 (E) 4 Introduction This European Standard is applicable and validated for several types of matrices as indicated in Table 1 (see also Annex A for the results of the validation). Table 1 Matrices for which this European Standard is applicable and vali
23、dated Matrix Materials used for validation Sludge Municipal sludge Biowaste Fresh compostCompost Soil Sludge amended soil Agricultural soil WARNING Persons using this European Standard should be familiar with usual laboratory practice. This European Standard does not purport to address all of the sa
24、fety problems, if any, associated with its use. It is the responsibility of the user to establish appropriate safety and health practices and to ensure compliance with any national regulatory conditions. IMPORTANT It is absolutely essential that tests conducted according to this European Standard be
25、 carried out by suitably trained staff. DIN EN 16169:2012-11EN 16169:2012 (E) 5 1 Scope This European Standard specifies the determination of Kjeldahl nitrogen according to the Kjeldahl procedure in sludge, treated biowaste and soil. Nitrate and nitrite are not included. Compounds with nitrogen boun
26、d in N-N, N-O linkages and some heterocycles (pyridines) are only partially determined. The limit of detection (LOD) is usually 0,03 % nitrogen, and the limit of quantification (LOQ) is 0,1 % nitrogen (using 0,25 mol/l sulfuric acid for titration). 2 Normative references The following documents, in
27、whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. EN 15934, Sludge, treated biowaste,
28、 soil and waste Calculation of dry matter fraction after determination of dry residue or water content EN 16179, Sludge, treated biowaste and soil Guidance for sample pretreatment EN ISO 3696, Water for analytical laboratory use Specification and test methods (ISO 3696) EN ISO 5667-15, Water quality
29、 Sampling Part 15: Guidance on the preservation and handling of sludge and sediment samples (ISO 5667-15) ISO 18512, Soil quality Guidance on long and short term storage of soil samples 3 Terms and definitions For the purpose of this document, the following terms and definitions apply. 3.1 Kjeldahl
30、nitrogen nitrogen that is contributed by free ammonia, inorganic ammonia compounds and those types of organic nitrogen compounds that are converted to ammonium sulfate by the digestion process described in this standard (catalytic sulfuric acid digestion) SOURCE: EN 13342:2000, 3.1 4 Principle The d
31、ried and homogenized, moist or liquid material is digested in a suitable Kjeldahl tube with sulfuric acid, thus converting most nitrogen compounds present to ammonium sulfate. To raise the temperature, potassium sulfate is added and e.g. a mixture of titanium dioxide and copper sulfate is used as a
32、catalyst. After adding sodium hydroxide to the digestion solution the produced ammonium is evaporated by distillation as ammonia. This is condensed in the cooling system and flows into a conical flask with boric acid solution (or diluted sulfuric acid). This solution is analyzed for ammonia by titra
33、tion with sulfuric or hydrochloric acid. DIN EN 16169:2012-11EN 16169:2012 (E) 6 5 Interferences and sources of errors The Kjeldahl method in principle does not capture all nitrogen compounds. The nitrogen that occurs in N-N and N-O linkages (e.g. azo-, nitro- and nitroso compounds, hydrazines, hydr
34、azones, oximes, pyrazolones, isooxazoles, dia- and triazines) is not completely recorded. Furthermore the inorganic fraction (nitrate and nitrite) is not determined. Another source of error includes contamination of the apparatus. Therefore the apparatus shall be rinsed after each analytical series
35、and blank determinations shall be carried out. The amount of sulfuric acid used in digestion process depends on the composition of the sample (see Table 2). A ratio of sample to acid of at least 1:10 (ratio weight to volume) shall be used for samples with high content of organic matter. Digestion bl
36、ock temperature shall not rise above 400 C to avoid analyte loss. Table 2 Amounts of sulfuric acid consumption by various materials during Kjeldahl digestion Material Consumption of sulfuric acid (36 mol/l) during digestion ml/g Soil, organic C 10,0 Soil, organic matter 5,8 Al2O31,63Fe2O31,04Clay 0,
37、60 CaCO30,55Silt 0,33Sand 0 Salicylic acid 6,76 Na2S2O30,58Reduced Fe 1,50 6 Reagents Use only reagents of recognized analytical grade, unless otherwise specified. 6.1 Water, complying with grade 2 according to EN ISO 3696. 6.2 Sulfuric acid, H2SO4, = 1,84 g/ml. 6.3 Catalyst mixture Grind and thorou
38、ghly mix 200 g of potassium sulfate (K2SO4), 20 g of copper sulfate pentahydrate (CuSO4 5 H2O) and 20 g of titanium dioxide (TiO2), with the crystal structure of anatase, to prepare a mixture: 10:1:1 = K2SO4:CuSO4:TiO2. This catalyst mixture is commercially available. 6.4 Sodium hydroxide, c(NaOH) =
39、 10 mol/l. DIN EN 16169:2012-11EN 16169:2012 (E) 7 6.5 Boric acid solution, H3BO3, = 20 g/l. 6.6 Mixed indicator Dissolve 0,1 g of bromocresol green and 0,02 g of methyl red in 100 ml ethanol. Mixed indicators are commercially available and may be used. 6.7 Sulfuric or hydrochloric acid solution, c(
40、H+) = 0,01 mol/l to 0,50 mol/l. 7 Apparatus Usual laboratory apparatus, and in particular the following: 7.1 Kjeldahl digestion flasks or tubes, suitable for digestion stand (7.2). 7.2 Digestion stand, suitable for digestion of samples with sulfuric acid at a temperature near to 400 C. 7.3 Distillat
41、ion apparatus, e.g. of the Parnas-Wagner-type or other suitable distillation apparatus with steam generator. 8 Sample storage and sample pretreatment Store soil samples according to ISO 18512 and sludge samples according to EN ISO 5667-15. For the purpose of this European Standard biowaste may be st
42、ored like soil. Pretreat the samples according to EN 16179, if not otherwise specified. Usually, they are dry, homogeneous and of a defined grain size, liquid or moist. Results are referred to dry mass, so that in case of liquid or moist samples a special sample shall be used for the determination o
43、f dry mass. Determine the dry mass of the sample according to EN 15934. 9 Procedure 9.1 General Homogeneity of the test sample shall be ensured. 9.2 Digestion Place a test portion of the dried sample, of about 0,2 g to 1 g, or an undried sample with the corresponding dry matter, to the nearest of 0,
44、1 % accuracy in the digestion flask or tube (7.1). Larger test portions are possible; the mass should be chosen according to the nitrogen content. To use the semi-micro or the macro method respective flasks or tubes shall be used with suitable volumes. Add 10 ml sulfuric acid (6.2). NOTE 1 The amoun
45、t of sulfuric acid may be adapted to the size of the flask or tube. Swirl until the acid is thoroughly mixed with the sample. Allow the mixture to stand and cool. Add 2,5 g of the catalyst mixture (6.3). DIN EN 16169:2012-11EN 16169:2012 (E) 8 Heat the digestion mixture until the sulfuric acid conde
46、nses on the wall of the tube and the brown colour has disappeared; then continue heating for at least another 60 min. Avoid digestion block temperatures exceeding 400 C to avoid losses of nitrogen. The use of a temperature programme that ensures gentle heating before reaching the boiling point is re
47、commended, especially for liquid samples or samples with high content of organic matter. NOTE 2 The boiling time may vary and depends on the sample material. The solution should be clear at the end of boiling. NOTE 3 The amounts of test material and added chemicals and catalysts may be changed adher
48、ing to the ratio described in the manufacturers instructions. NOTE 4 The semi-micro and the macro versions of the Kjeldahl procedure are suitable for some materials. 9.3 Titration After completion of the digestion step, allow the flask or tube to cool and add 20 ml of water (6.1) slowly while shaking. Then swirl the flask or tube to bring any insoluble material into suspension and transfer the contents to the distillation apparatus (7.3). Rinse th
