1、 DEUTSCHE NORMJune 2006DIN EN 14701-1 ICS 13.030.20 Characterisation of sludges Filtration properties Part 1: Capillary suction time (CST) English version of DIN EN 14701-1:2006-06 Charakterisierung von Schlmmen Filtrationseigenschaften Teil 1: Bestimmung der kapillaren Fliezeit Englische Fassung DI
2、N EN 14701-1:2006-06 Document comprises 17 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 10
3、 www.din.de www.beuth.de !,o-M“10.06 9761042DIN EN 14701-1:2006-06 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 Normena
4、usschuss Wasserwesen (Water Practice Standards Committee), Technical Committee NA 119-01-02 AA 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 57
5、25-2, Accuracy (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 14701-1March 2006ICS 13.030.20English VersionCharacterisation
6、of sludges - Filtration properties - Part 1:Capillary suction time (CST)Caractrisation des boues - Proprits de filtration - Partie1: Dtermination du temps de succion capillaireCharakterisierung von Schlmmen -Filtrationseigenschaften - Teil 1: Bestimmung der kapillarenFliezeitThis European Standard w
7、as approved by CEN on 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 na
8、tionalstandards 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 member into its own language and not
9、ified 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, Lithuania, Luxembourg, Malta, Netherlan
10、ds, 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 All rights of exploitation in any
11、form and by any means reservedworldwide for CEN national Members.Ref. No. EN 14701-1:2006: EEN 14701-1:2006 (E) 2 Contents Page Foreword3 1 Scope 5 2 Normative references 5 3 Terms and definitions .5 4 Principle5 5 Apparatus .6 5.1 Standard apparatus .6 5.2 Filter paper .6 5.3 Beakers .6 6 Procedure
12、 .6 7 Expression of results 6 8 Precision.7 9 Test report 7 Annex A (informative) Simple automatic instrument for determining the filterability of sewage sludge .8 Annex B (informative) Relation between CST and the specific resistance to filtration .9 Annex C (informative) Relation between CST and s
13、olids content .10 Annex D (informative) Table of dynamic viscosity 11 Annex E (informative) Results of validation trials .12 Bibliography 15 EN 14701-1:2006 (E) 3 Foreword This document (EN 14701-1:2006) has been prepared by Technical Committee CEN/TC 308 “Characterisation of sludges”, the secretari
14、at 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 September 2006. Other parts of
15、this European Standard are: Part 2: Determination of the specific resistance to filtration; Part 3: Determination of the compressibility. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard:
16、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 United Kingdom. EN 14701-1:2006 (E)
17、 4 Introduction The capillary suction time (CST) is a fast and simple way to evaluate the sludge dewaterability by filtration. This method gives no information on the obtainable solids content in a dewatering process. The measurement of CST should also make possible the evaluation, although only qua
18、litatively, of other sludge characteristics, including dewaterability by centrifugation. EN 14701-1:2006 (E) 5 1 Scope This document specifies a method for the determination of the capillary suction time. This document is applicable to sludge and sludge suspensions from: storm water handling; urban
19、wastewater collecting systems; urban wastewater treatment plants; treating industrial wastewater 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 followi
20、ng 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 12832:1999, Characterization of sludges Utilization and d
21、isposal of sludges Vocabulary 3 Terms and definitions For the purposes of this document, the terms and definitions given in EN 12832:1999 and the following apply. 3.1 filterability property indicating the amenability of a sludge to be dewatered by a filtration process 3.2 capillary suction time (CST
22、) measurement of the time for a wetting front in a filter paper to travel between two fixed points 4 Principle The principle of the method is that dewatering is achieved by the suction applied to the sludge by the capillary action of an absorbent filter paper. A part of the absorbent paper area is e
23、xposed to the sludge, while the remaining area is free for absorbing the filtrate. The rate at which the paper becomes wetted with filtrate is a measure correlated to sludge dewaterability: it is measured by the time necessary for the filtrate to cover the space between two probes which detect the a
24、dvancement of the liquid front on the paper (Annex A informative). The CST measurements are strongly affected by many factors, such as properties of the paper, surface tension, temperature, suspended solids concentration, so they give only qualitative and comparative evaluations which can be correla
25、ted to the specific resistance to filtration (prEN 14701-2) for a given type of sludge (Annex B informative). EN 14701-1:2006 (E) 6 5 Apparatus 5.1 Standard apparatus Device consisting of: a) filtration apparatus, including base for supporting the absorbent paper, sludge reservoir and probes; b) aut
26、omatic time recording unit, including amplifier and digital electric stop-clock recording in seconds (see Annex A informative). 5.2 Filter paper Paper suitable for chromatography with grain parallel with the longer side (for instance, Whatman n. 17 or Wickam CST Papers 7 cm x 9 cm code 8680841). NOT
27、E For comparable results the same filter paper type should be used. 5.3 Beakers Conventional beakers, 50 ml minimum. 6 Procedure 6.1 Place a filter paper in the apparatus. The filter paper shall always be placed with the same side up. 6.2 Mix the sludge to be tested by pouring it off from a beaker t
28、o another for 4 times. 6.3 Pour immediately the mixed sludge into the reservoir until it is completely full. Great attention shall be paid in performing measurements immediately after the sludge mixing to avoid any result unreliability due to sludge settling into the beaker (especially for condition
29、ed sludges). 6.4 When the clock stops, register the time which has been automatically measured. 6.5 Repeat steps 6.1 to 6.4 in order to have at least 3 significant values, as stated in Clause 7. 7 Expression of results The CST value is given by arithmetically averaging the measured values. If one or
30、 more values differ of more than 20% from the calculated mean value, they must not be considered and the average shall be calculated again with remaining values: in any case valid values shall be, at least, 3. The influence of the temperature may be evaluated through the relationship: CST1= (1/2) CS
31、T2(1) where 1and 2are the dynamic viscosities of water at the two considered temperatures. 1) This information is given for the convenience of users of this document and does not constitute an endorsement by CEN of this product. Equivalent products may be used if they can be shown to lead to the sam
32、e results. EN 14701-1:2006 (E) 7 If the room temperature is between 12 C and 30 C, the influence of the temperature can be neglected. Water viscosities as a function of temperature are reported in the table in Annex D (informative). 8 Precision Results of validation trials are summarized in Annex E
33、(informative). The repeatability standard deviation ranges from 0,411 s (3,6 %) for activated/thickened sewage sludge, to 0,463 s (4,4 %) for activated sewage sludge, to 1,560 s (3,4 %) for waterworks sludge, and to 7,856 s (5,3 %) for digested sewage sludge. Mean value is 2,573 s (4,9 %). Minimum p
34、recision is 5,3 %. The reproducibility standard deviation ranges from 0,643 s (5,6 %) for activated/thickened sewage sludge, to 1,043 s (9,9 %) for activated sewage sludge, to 2,023 s (4,4 %) for waterworks sludge, and to 20,01 s (14,0 %) for digested sewage sludge. Mean value is 5,929 s (11,3 %). M
35、inimum precision is 14,0 %. 9 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 pre-treatment, if carried out; d) information about the size of th
36、e reservoir used; e) results of the determination according to Clause 7; f) any detail not specified in this document or which are optional and any other factor which may have affected the results. EN 14701-1:2006 (E) 8 Annex A (informative) Simple automatic instrument for determining the filterabil
37、ity of sewage sludge The CST apparatus by Triton as described in 1 consists of a base supporting a rectangular piece of 7 cm x 9 cm of absorbent filter paper and a block holding probes above it; in the centre of the upper block (which stands clear of the paper by resting on five stainless steel supp
38、orts) there is a circular hole in which a stainless steel reservoir (18 mm bore/25 mm high or 10 mm bore/50 mm high) loosely fit. On the under side of the upper block there are two engraved circles, of 3,2 cm and 4,5 cm in diameter, concentric with the reservoir; two of the supports are specially ma
39、chined probes in line with the first concentric circle and one with the second circle. Both probes are electrically connected to the recording unit. For this apparatus, the CST values of raw sewage sludge generally range 60 s to 300 s, using the 18 mm reservoir and the kind of papers reported before
40、 (see 5.2). The 18 mm reservoir is more suitable for low-dewaterable sludges: significant values range 10 s to 900 s. The use of the 10 mm reservoir is necessary for easily filterable sludges: significant values range 20 s to 1 200 s. For high filterable sludges, having very low CST, 2 overlapped fi
41、lter papers could be used. The 10 mm reservoir can be difficult to fill, especially with thick sludges. The 18 mm reservoir has been found to be suitable for use with most sewage sludges, but other dimensions may be more suitable for other types of suspension. EN 14701-1:2006 (E) 9 Annex B (informat
42、ive) Relation between CST and the specific resistance to filtration The variation of CST with specific resistance to filtration for 18 mm and 10 mm diameter reservoirs for sewage sludges is reported in Baskerville and Gale (1968) 1. The relationship between CST and the specific resistance, measured
43、through the Buchner procedure, was also studied by Smollen (1986) 2, and Spinosa et al. (1991) 3. EN 14701-1:2006 (E) 10 Annex C (informative) Relation between CST and solids content The variation of CST with solids content is discussed in Vesilind (1988) 4. EN 14701-1:2006 (E) 11 Annex D (informati
44、ve) Table of dynamic viscosity Table D.1 Dynamic viscosity of water from 0 C to 40 C T (C) Viscosity (10-3Pa s) T (C) Viscosity (10-3Pa s) 0 1,7921 26 0,8737 1 1,7313 27 0,8545 2 1,6728 28 0,8360 3 1,6191 29 0,8180 4 1,5674 30 0,8007 5 1,5188 31 0,7840 6 1,4728 32 0,7679 7 1,4284 33 0,7523 8 1,3860
45、34 0,7371 9 1,3462 35 0,7225 10 1,3077 36 0,7085 11 1,2713 37 0,6947 12 1.2663 38 0,6814 13 1,2028 39 0,6685 14 1,1709 40 0,6560 15 1,1404 16 1,1111 17 1,0828 18 1,0559 19 1,0299 20 1,0050 20,2 1,0000 21 0,9810 22 0,9579 23 0,9358 24 0,9142 25 0,8937 NOTE 1 10-3Pa s = 10-2g/cm s = 1 centipoise. NOTE
46、 2 It is assumed that filtrate viscosity is equal to water viscosity. EN 14701-1:2006 (E) 12 Annex E (informative) Results of validation trials Because the circulation of samples of real sludge high in organic content is not possible due to problems associated to changes in their physical characteri
47、stics 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, the round robin tests are carried out through “circulation of analysts”, i. e. operators coming from th
48、e 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 were carried out at LUA, Dsseldorf, on 28 September 2004. Trials involved a total of 11 Operators from t
49、he 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 (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): 2,81 Sample 2: Sewage sludge digested Dry residue (%): 2,22 Sample 3: Waterworks sludge Dry residue (%): 3,62
