1、BRITISH STANDARDBS EN 14701-1:2006Characterization of sludges Filtration properties Part 1: Capillary suction time (CST)The European Standard EN 14701-1:2006 has the status of a British StandardICS 13.030.20g49g50g3g38g50g51g60g44g49g42g3g58g44g55g43g50g56g55g3g37g54g44g3g51g40g53g48g44g54g54g44g50g
2、49g3g40g59g38g40g51g55g3g36g54g3g51g40g53g48g44g55g55g40g39g3g37g60g3g38g50g51g60g53g44g42g43g55g3g47g36g58Licensed Copy: Wang Bin, na, Tue Aug 21 00:59:46 GMT+00:00 2007, Uncontrolled Copy, (c) BSIBS EN 14701-1:2006This British Standard was published under the authority of the Standards Policy and
3、Strategy Committee on 30 April 2007 BSI 2007ISBN 978 0 580 50510 2National forewordThis British Standard was published by BSI. It is the UK implementation of EN 14701-1:2006.The UK participation in its preparation was entrusted to Technical Committee EH/5, Sludge characterization.A list of organizat
4、ions represented on EH/5 can be obtained on request to its secretary.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
5、British method was selected. The method has long been used as a valuable 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 p
6、roperties do not change) to laboratories for international interlaboratory 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
7、 not specify all such operational details, the performance data are 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
8、 of a contract. Users are responsible for its correct application.Compliance with a British Standard cannot confer immunity from legal obligations. Amendments issued since publicationAmd. No. Date CommentsLicensed Copy: Wang Bin, na, Tue Aug 21 00:59:46 GMT+00:00 2007, Uncontrolled Copy, (c) BSIEURO
9、PEAN STANDARDNORME EUROPENNEEUROPISCHE NORMEN 14701-1March 2006ICS 13.030.20English VersionCharacterization of sludges - Filtration properties - Part 1:Capillary suction time (CST)Caractrisation des boues - Proprits de filtration - Partie1: Dtermination du temps de succion capillaireCharakterisierun
10、g von Schlmmen -Filtrationseigenschaften - Teil 1: Bestimmung der kapillarenFliezeitThis European Standard was 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
11、national standard without any alteration. Up-to-date lists and bibliographical 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
12、any other language made by translationunder the responsibility of a CEN member 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, Finlan
13、d, France,Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania,Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.EUROPEAN COMMITTEE FOR STANDARDIZATIONCOMIT EUROPEN DE NORMALISATIONEUROPISCHES KOMITEE
14、FR NORMUNGManagement Centre: rue de Stassart, 36 B-1050 Brussels 2006 CEN All rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN 14701-1:2006: ELicensed Copy: Wang Bin, na, Tue Aug 21 00:59:46 GMT+00:00 2007, Uncontrolled Copy, (c) BSIEN 14701-
15、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 .6 7 Expression of results 6 8 Precision.7 9 Test report 7 Annex A (informative) Simple automatic in
16、strument 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 solids content .10 Annex D (informative) Table of dynamic viscosity 11 Annex E (informative) Results o
17、f validation trials .12 Bibliography 15 Licensed Copy: Wang Bin, na, Tue Aug 21 00:59:46 GMT+00:00 2007, Uncontrolled Copy, (c) BSIEN 14701-1:2006 (E) 3 Foreword This document (EN 14701-1:2006) has been prepared by Technical Committee CEN/TC 308 “Characterization of sludges”, the secretariat of whic
18、h 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 this Europ
19、ean 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: Austria, B
20、elgium, 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. Licensed Copy: Wang Bin, na,
21、Tue Aug 21 00:59:46 GMT+00:00 2007, Uncontrolled Copy, (c) BSIEN 14701-1:2006 (E) 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. T
22、he measurement of CST should also make possible the evaluation, although only qualitatively, of other sludge characteristics, including dewaterability by centrifugation. Licensed Copy: Wang Bin, na, Tue Aug 21 00:59:46 GMT+00:00 2007, Uncontrolled Copy, (c) BSIEN 14701-1:2006 (E) 5 1 Scope This docu
23、ment 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 wastewater collecting systems; urban wastewater treatment plants; treating industrial wastewater similar to urban wastewater (as
24、 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 references, only the edition cited app
25、lies. For undated references, the latest edition of the referenced document (including any amendments) applies. EN 12832:1999, Characterization of sludges Utilization and disposal of sludges Vocabulary 3 Terms and definitions For the purposes of this document, the terms and definitions given in EN 1
26、2832:1999 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) measurement of the time for a wetting front in a filter paper to travel between two fixed points 4 Principle The principle of
27、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 exposed to the sludge, while the remaining area is free for absorbing the filtrate. The rate at which the paper becomes wetted wi
28、th 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 advancement of the liquid front on the paper (Annex A informative). The CST measurements are strongly affected by many factors, s
29、uch as properties of the paper, surface tension, temperature, suspended solids concentration, so they give only qualitative and comparative evaluations which can be correlated to the specific resistance to filtration (prEN 14701-2) for a given type of sludge (Annex B informative). Licensed Copy: Wan
30、g Bin, na, Tue Aug 21 00:59:46 GMT+00:00 2007, Uncontrolled Copy, (c) BSIEN 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) automatic time recording unit, including
31、 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). NOTE For comparable results the same fil
32、ter 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 to another for 4 times. 6.3 Pour immed
33、iately 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 conditioned sludges). 6.4 When the clock stops
34、, 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 more values differ of more than 20%
35、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) CST2(1) where 1and 2are the dynamic vis
36、cosities 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 same results. Licensed Copy: Wang Bin, n
37、a, Tue Aug 21 00:59:46 GMT+00:00 2007, Uncontrolled Copy, (c) BSIEN 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 R
38、esults of validation trials are summarized in Annex E (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 s
39、ewage sludge. Mean value is 2,573 s (4,9 %). Minimum precision 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 dig
40、ested sewage sludge. Mean value is 5,929 s (11,3 %). Minimum 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-treatmen
41、t, if carried out; d) information about the size of the 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. Licensed Copy: Wang Bin, na, Tue Aug 21 00:59:46
42、 GMT+00:00 2007, Uncontrolled Copy, (c) BSIEN 14701-1:2006 (E) 8 Annex A (informative) Simple automatic instrument for determining the filterability 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 pap
43、er 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 supports) 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
44、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 machined probes in line with the first concentric circle and one with the second circle. Both probes are electrically connected to the recording unit. For th
45、is 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 (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 nec
46、essary for easily filterable sludges: significant values range 20 s to 1 200 s. For high filterable sludges, having very low CST, 2 overlapped filter 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 f
47、or use with most sewage sludges, but other dimensions may be more suitable for other types of suspension. Licensed Copy: Wang Bin, na, Tue Aug 21 00:59:46 GMT+00:00 2007, Uncontrolled Copy, (c) BSIEN 14701-1:2006 (E) 9 Annex B (informative) Relation between CST and the specific resistance to filtrat
48、ion 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 through the Buchner procedure, was also studied by Smollen (1986
49、) 2, and Spinosa et al. (1991) 3. Licensed Copy: Wang Bin, na, Tue Aug 21 00:59:46 GMT+00:00 2007, Uncontrolled Copy, (c) BSIEN 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. Licensed Copy: Wang Bin, na, Tue Aug 21 00:59:46 GMT+00:00 2007, Uncontrolled Copy, (c) BSIEN 14701-1:2006 (E) 11 Annex D (informative) 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) V
