SIST EN 14702-2:2006

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Characterisation of sludges - Settling properties - Part 2: Determination of thickenabilityRãþHYDQMDCaractérisation des boues - Propriétés de sédimentation - Partie 2: Détermination de l'aptitude a l'épaississementCharakterisierung von Schlämmen - Absetzeigenschaften - Teil 2: Bestimmung der Eindickbarkeit13.030.20Liquid wastes. SludgeICS:SIST EN 14702-2:2006en,fr,deTa slovenski standard je istoveten z:EN 14702-2:200601-julij-2006SIST EN 14702-2:2006SLOVENSKI
STANDARD







EUROPEAN STANDARDNORME EUROPÉENNEEUROPÄISCHE NORMEN 14702-2March 2006ICS 13.030.20 English VersionCharacterisation of sludges - Settling properties - Part 2:Determination of thickenabilityCaractérisation des boues - Propriétés de sédimentation -Partie 2: Détermination de l'aptitude à l'épaississementCharakterisierung von Schlämmen - Absetzeigenschaften -Teil 2: Bestimmung der EindickbarkeitThis 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 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 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, 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.EUROPEAN COMMITTEE FOR STANDARDIZATIONCOMITÉ EUROPÉEN DE NORMALISATIONEUROPÄISCHES KOMITEE FÜR NORMUNGManagement Centre: rue de Stassart, 36
B-1050 Brussels© 2006 CENAll rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN 14702-2:2006: E



EN 14702-2:2006 (E) 2 Contents Page Foreword.3 Introduction.4 1 Scope.5 2 Normative references.5 3 Terms and definitions.5 4 Principle.5 5 Interferences.5 6 Apparatus.6 7 Procedure.6 8 Expression of results.6 9 Precision.6 10 Test 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 “Characterisation 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 September 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 implement 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 United 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 particle 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 14702-2:2006 (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 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 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 1085:1997, Waste water treatment — Vocabulary 3 Terms and definitions For the purposes of this document, the terms and definitions given in EN 1085:1997 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 sludge 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 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 g/l has been found
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