1、 DEUTSCHE NORMJune 2006DIN EN 14702-2 ICS 13.030.20 Characterisation of sludges Settling properties Part 2: Determination of thickenability English version of DIN EN 14702-2:2006-06 Charakterisierung von Schlmmen Absetzeigenschaften Teil 2: Bestimmung der Eindickbarkeit Englische Fassung DIN EN 1470
2、2-2:2006-06 Document comprises 14 pages No part of this standard may be reproduced without prior permission of DIN Deutsches Institut fr Normung e. V., Berlin. Beuth Verlag GmbH, 10772 Berlin, Germany, has the exclusive right of sale for German Standards (DIN-Normen). English price group 8 www.din.d
3、e www.beuth.de !,o-P“10.06 9761045DIN EN 14702-2:2006-06 2 National foreword This standard has been prepared by CEN/TC 308 Characterisation of sludges (Secretariat: France), Working Group WG 1 Characterisation methods. The responsible German body involved in its preparation was the Normenausschuss W
4、asserwesen (Water Practice Standards Committee), Technical Committee NA 119-01-02 Boden- und Abfalluntersuchung. The national standards bodies are bound to adopt this European Standard in its entirety and without any modifications. National Annex NA (informative) Bibliography DIN ISO 5725-2, Accurac
5、y (trueness and precision) of measurement methods and results Part 2: Basic method for the determination of repeatability and reproducibility of a standard measurement method EUROPEAN STANDARDNORME EUROPENNEEUROPISCHE NORMEN 14702-2March 2006ICS 13.030.20English VersionCharacterisation of sludges -
6、Settling properties - Part 2:Determination of thickenabilityCaractrisation des boues - Proprits de sdimentation -Partie 2: Dtermination de laptitude lpaississementCharakterisierung von Schlmmen - Absetzeigenschaften -Teil 2: Bestimmung der EindickbarkeitThis European Standard was approved by CEN on
7、3 February 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 bibliographical references concerning such nationalstandards may be
8、 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 member into its own language and notified to the Central S
9、ecretariat 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, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Po
10、rtugal, 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 All rights of exploitation in any form and by any means
11、reservedworldwide for CEN national Members.Ref. No. EN 14702-2:2006: EEN 14702-2:2006 (E) 2 Contents Page Foreword3 Introduction .4 1 Scope 5 2 Normative references 5 3 Terms and definitions .5 4 Principle5 5 Interferences 5 6 Apparatus .6 7 Procedure .6 8 Expression of results 6 9 Precision.6 10 Te
12、st report 7 Annex A (informative) Stirred cylinder for determining the thickenability of sludges 8 Annex B (informative) Results of validation trials .9 Bibliography 12 EN 14702-2:2006 (E) 3 Foreword This document (EN 14702-2:2006) has been prepared by Technical Committee CEN/TC 308 “Characterisatio
13、n 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 September 2006, and conflicting national standards shall be withdrawn at the latest by Sep
14、tember 2006. Another part of this European Standard is: Part 1: Determination of settleability (Determination of the proportion of sludge volume and sludge volume index). According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to i
15、mplement this European Standard: Austria, Belgium, Cyprus, Czech Republic, 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 Un
16、ited Kingdom. EN 14702-2:2006 (E) 4 Introduction Determination of the thickenability, i.e. the further concentration of suspended (undissolved) sludge solids in settling under gravity, through the use of laboratory mechanical assisted cylinders is negatively affected by bridging, wall effects and pa
17、rticle size effects. Ideally, this parameter should be measured in large-diameter columns having the same depth as the prototype thickener, but above effects can be satisfactory overcome by introducing a low-speed stirrer in a cylinder; this also helps to reduce the effect of the shallow depth. EN 1
18、4702-2:2006 (E) 5 1 Scope This document specifies a method for the determination of the thickenability of sludge suspensions. This document is applicable to sludge suspensions from: storm water handling; urban wastewater collecting systems; urban wastewater treatment plants; treating industrial wast
19、ewater similar to urban wastewater (as defined in Directive 91/271 EEC); water supply treatment plants. This method is also applicable to sludge suspensions from other origin. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated
20、references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. EN 1085:1997, Waste water treatment Vocabulary 3 Terms and definitions For the purposes of this document, the terms and definitions given in EN 1085:1
21、997 and the following apply. 3.1 thickenability ability of sludge solids to further concentrate in mechanical assisted settling under gravity 3.2 stirred sludge volume volume of the sludge suspension after settling under specified stirring conditions 3.3 stirred sludge volume index quotient of sludg
22、e volume by the concentration by mass of dry matter in the sludge, measured in a stirred cylinder 4 Principle The thickenability is determined by the proportion of the total volume occupied by the sludge in a sludge suspension within 30 min after settling under gentle stirring in standard apparatus
23、and under standard conditions. 5 Interferences Settling properties vary with the solids concentration. Therefore, the comparison of these properties of sludge suspensions having different solids concentrations is allowed if a reference concentration is assumed; the EN 14702-2:2006 (E) 6 value of 3,5
24、 g/l has been found to be the optimal one 1. Settling properties evaluated at this solids concentration value also correlate well with the maximum solids loading at which that sludge may be applied to a tank without loss of solids in the effluent. Interference occurs when there are fairly large temp
25、erature differences between the temperature of the sample and the ambient temperature as a result of convection and formation of gas bubbles. With differences of more than 5 C it is advisable to place the settling cylinder with the sample in a bucket filled with the sample fluid. 6 Apparatus 6.1 gra
26、duated cylinder, diameter 10 cm, measuring height 50 cm, nominal volume 3 500 ml, made of glass or transparent plastic, equipped with a low speed stirrer at 1 rpm. The stirrer is in 1 (Annex A (informative). 6.2 scoop, nominal volume 5 l. 7 Procedure A representative sample of sludge suspension is t
27、aken by the scoop and immediately poured into the graduated cylinder up to the 50 cm mark. For this purpose, a scoop holding 5 l is used. Start the stirrer and record the level of sludge-water interface in the cylinder after 30 min. For measurements at the reference concentration of 3,5 g/l, sludge
28、samples shall be obtained through dilution by supernatant liquor followed by gentle homogenisation. 8 Expression of results The stirred sludge volume (Vss) is obtained as the quotient of the sludge volume after stirring (Clause 4) by the volume of the initial sludge sample volume. It is given in mil
29、lilitres by litre as an average of at least two measurements. The stirred sludge volume index (Issv) is calculated from the equation below: ()0ssv50000 1CHI= where H is the final sludge level in centimetres; C0is the initial solids concentration, in grams per litre (see EN 12880); 50 is the starting
30、 height of sludge suspension, in centimetres; 1 000 is a conversion factor. NOTE For activated sludges, plant values of Issvat 3,5 g/l lower than 80 ml/g are indicative of good thickenability, while values higher than 120 ml/g of poor thickenability. 9 Precision Results of validation trials are summ
31、arized in Annex B (informative). EN 14702-2:2006 (E) 7 The reproducibility standard deviation ranges from 0,22 ml/g (0,5 %) for digested sewage sludge, to 0,28 ml/g (1,0 %) for waterworks sludge, to 1,03 ml/g (1,1 %) for activated/thickened sewage sludge, and to 1,71 ml/g (1,8 %) for activated sewag
32、e sludge. Mean value is 0,88 ml/g (1,2 %). Minimum precision is 1,8 %. 10 Test report The test report shall contain the following information: a) reference to this document; b) all information necessary for the complete identification of the sludge sample; c) details of sample preparation; e. g. dil
33、ution; d) results of the determination according to Clause 8; e) any details not specified in this document or which are optional and any other factor which may have affected the results. EN 14702-2:2006 (E) 8 Annex A (informative) Stirred cylinder for determining the thickenability of sludges The a
34、pparatus, as derived from that derived in 1, consists of a graduated transparent cylinder, diameter 10 cm, measuring height 50 cm, equipped with a low-speed stirrer at 1 rpm. The stirrer consists of two vertical rods, diameter 0,5 cm to 0,6 cm, places asymmetrically to the cylinder axis, the first a
35、t a distance from the cylinder wall of about 0,3 cm, the second at a distance from the cylinder wall of about 2,5 cm, with a remaining distance between them of about 5,0 cm. EN 14702-2:2006 (E) 9 Annex B (informative) Results of validation trials Because the circulation of samples of real sludge hig
36、h in organic content is not possible due to problems associated to changes in their physical characteristics during handling and transportation, the “Modified Round Robin Tests” procedure, developed by TG 3 of CEN/TC 308/WG 1, and reported in doc CEN/TC 308 N 822, was followed. With this procedure,
37、the round robin tests are carried out through “circulation of analysts”, i. e. operators coming from the laboratories participating to the exercise meet in a common location, close to the place where samples are collected, and work there on same samples, each using own apparatus. Validation trials w
38、ere carried out at LUA, Dsseldorf, on 29 September 2004. Trials involved a total of 11 Operators from the following 9 Laboratories/Institutions in 3 Countries: ARPA Puglia (Bari, I), CEMAGREF (Montaldre, F), CNR-IRSA (Bari, I), Comm. Env. Emerg. in Puglia Region (Bari, I), DIN (Berlin, D), LUA-NRW (
39、Dsseldorf, D), STUA (Lippstadt, D), UBA (Berlin, D), University of Lecce (I). The following 4 different sludge types were tested: Sample 1: Sewage sludge activated Solids concentration (g/l): 2,71 Sample 2: Sewage sludge digested Dry residue (%): 2,21 Sample 3: Waterworks sludge Dry residue (%): 3,6
40、2 Sample 4: Sewage sludge activated/thickened Dry residue (%): 0,75 (analyses for measuring solids concentration and/or dry residue were carried out at the Chemical-biological Laboratory of Landeshauptstadt in Dsseldorf) Test results have been statistically analysed for the evaluation of precision a
41、ccording to ISO 5725-2. In particular, the repeatability standard deviation sr(for cells containing more than one figure), and the reproducibility standard deviation sRwere calculated. The tables of results which follow contain the following symbols: i is the operator number; j is the level (sample)
42、 number; k (= 1, 2, ., n) is the test number; n are the replicates; nijis the number of test results in the cell for operator (i) at level (j); p is the total number of operators (i) (i = 1, 2, , p); q are the total testing levels (batches of materials) (j) (j = 1, 2, , q); EN 14702-2:2006 (E) 10 sr
43、is the repeatability standard deviation; sRis the reproducibility standard deviation; ijis the cell means; y is the test result; yijkis the result of the test number (k) for operator (i) at level/sample (j). Table B.1 Readings Operator number (i) Level (j) Sample 1 Level Sample 2 Level Sample 3 Leve
44、l Sample 4 (= q) values (yijk) cm mean (ij) cm values (yijk) cm mean (ij) cm values (yijk) cm mean (ij) cm values (yijk) cm mean (ij) cm 1 13,0 13,0 49,1 49,1 49,3 49,3 35,4 35,4 2 13,0 13,0 49,0 49,0 49,2 49,2 3 13,0 13,0 49,0 49,0 49,3 49,3 34,7 34,7 4 13,0 13,0 49,0 49,0 49,0 49,0 5 13,2 13,2 49,
45、2 49,2 49,4 49,4 35,5 35,5 6 49,3 49,3 7 13,5 13,5 48,9 48,9 49,3 49,3 8 13,5 13,5 48,5 48,5 49,1 49,1 34,7 34,7 9 13,2 13,2 48,7 48,7 49,6 49,6 35,0 35,0 10 (= p) 13,5 13,5 48,6 48,6 49,4 49,4 34,6 34,6 Mean at level (j) 13,2 48,9 49,3 35,0 NOTE Stirred settling apparatuses used for tests were of t
46、he standard Type 305 produced by Triton Electronics, Dunmow, Essex (UK). EN 14702-2:2006 (E) 11 Table B.2 Stirred sludge volume index, ISSVOperator number (i) Level (j) Sample 1 Level Sample 2 Level Sample 3 Level Sample 4 (= q) values (yijk) ml/g mean (ij) ml/g values (yijk) ml/g mean (ij) ml/g val
47、ues (yijk) ml/g mean (ij) ml/g values (yijk) ml/g mean (ij) ml/g 1 95,94 95,94 44,44 44,44 27,21 27,21 94,41 94,41 2 95,94 95,94 44,35 44,35 27,16 27,16 3 95,94 95,94 44,35 44,35 27,21 27,21 92,54 92,54 4 95,94 95,94 44,35 44,35 27,05 27,05 5 97,42 97,42 44,53 44,53 27,27 27,27 94,68 94,68 6 27,21 2
48、7,21 7 99,63 99,63 44,25 44,25 27,21 27,21 8 99,63 99,63 43,89 43,89 27,10 27,10 92,54 92,54 9 97,42 97,42 44,07 44,07 27,38 27,38 93,35 93,35 10 (= p) 99,63 99,63 43,98 43,98 27,27 27,27 92,28 92,28 Mean at level (j) 97,42 44,25 27,21 93,35 Table B.3 Reproducibility standard deviation, sRSample sRm
49、l/g sR% 1) Sewage sludge, activated 1,71 1,8 2) Sewage sludge, digested 0,22 0,5 3) Waterworks sludge 0,28 1,0 4) Sewage sludge, activated/thickened 1,03 1,1 Mean value 0,88 1,2 EN 14702-2:2006 (E) 12 Bibliography 1 White, M.I.D., Instruction Manual for WRC settling operations for activated sludge, WRC TM 103 (1975). 2 91/271/EEC Council Directive of 21 May 1991 concerning urban waste water treatment, ABl EG, 1991, N L 135, 40-52. 3 ISO 5725-2, A
