ASTM_D_2035_-_13.pdf

Designation:D203513Standard Practice forCoagulation-Flocculation Jar Test of Water1This standard is issued under the fixed designation D2035;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This practice covers a general procedure for the evalu-ation of a treatment to reduce dissolved,suspended,colloidal,and nonsettleable matter from water by chemical coagulation-flocculation,followed by gravity settling.The procedure maybe used to evaluate color,turbidity,and hardness reduction.1.2 The practice provides a systematic evaluation of thevariables normally encountered in the coagulation-flocculationprocess.1.3 The values stated in SI units are to be regarded asstandard.1.4 This standard does not purport to address the safetyconcerns,if any,associated with its use.It is the responsibilityof the user of this standard to establish appropriate safety andhealth practices and determine the applicability of regulatorylimitations prior to use.2.Referenced Documents2.1 ASTM Standards:2D1129 Terminology Relating to WaterD1193 Specification for Reagent WaterD1293 Test Methods for pH of WaterD3370 Practices for Sampling Water from Closed ConduitsD6855 Test Method for Determination of Turbidity Below 5NTU in Static ModeD7315 Test Method for Determination of Turbidity Above 1Turbidity Unit(TU)in Static Mode3.Terminology3.1 DefinitionsFor definitions of terms used in thispractice,refer to Terminology D1129.4.Summary of Practice4.1 The coagulation-flocculation test is carried out to deter-mine the chemicals,dosages,and conditions required toachieve optimum results.The primary variables to be investi-gated using the recommended practice include,but are notlimited to:4.1.1 Chemical additives,4.1.2 pH,4.1.3 Temperature,and4.1.4 Order of addition and mixing conditions.5.Significance and Use5.1 This practice permits the evaluation of various coagu-lants and coagulant aids used in the treatment of water andwaste water for the same water and the same experimentalconditions.5.2 The effects of concentration of the coagulants andcoagulant aids and their order of addition can also be evaluatedby this practice.6.Interferences6.1 There are some possible interferences that may make thedetermination of optimum jar test conditions difficult.Theseinclude the following:6.1.1 Temperature Change(During Test)Thermal or con-vection currents may occur,interfering with the settling ofcoagulated particles.This can be prevented by temperaturecontrol.6.1.2 Gas Release(During Test)Flotation of coagulatedfloc may occur due to gas bubble formation caused bymechanical agitator,temperature increase or chemical reaction.6.1.3 Testing-Period Biological activity or other factorsmay alter the coagulation characteristics of water upon pro-longed standing.For this reason the period between samplingand testing should be kept to a minimum,with the time beingrecorded.7.Apparatus7.1 Multiple Stirrer A multiposition stirrer with continu-ous speed variation from about 20 to 150 rpm should be used.The stirring paddles should be of light gage corrosion-resistantmaterial all of the same configuration and size.An illuminatedbase is useful to observe the floc formation.Precautionary1This practice is under the jurisdiction of ASTM Committee D19 on Water andis the direct responsibility of Subcommittee D19.03 on Sampling Water andWater-Formed Deposits,Analysis of Water for Power Generation and Process Use,On-Line Water Analysis,and Surveillance of Water.Current edition approved Jan.1,2013.Published February 2013.Originallyapproved in 1964.Last previous edition approved in 2008 as D2035 08.DOI:10.1520/D2035-13.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 measures should be taken to avoid heat being imparted by theillumination system which may counteract normal settling.7.2 Jars(or Beakers),all of the same size and shape;1500-mLGriffin beakers may be used(1000-mLrecommendedminimum size).7.3 Reagent Racks A means of introducing each testsolution to all jars simultaneously.There should be at least onerack for each test solution or suspension.The racks should besimilar to that shown in Fig.1.8.Reagents8.1 Purity of ReagentsReagent grade chemicals shall beused in all tests.Unless otherwise indicated,it is intended thatall reagents shall conform to the specifications of the Commit-tee on Analytical Reagents of the American Chemical Society,where such specifications are available.3Other grades may beused,provided it is first ascertained that