1、Designation: D4188 13Standard Practice forPerforming Pressure In-Line Coagulation-Flocculation-Filtration Test in Water1This standard is issued under the fixed designation D4188; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the
2、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. Scope*1.1 This practice covers the procedure used to performpressure in-line coagulation-flocculation-filtration of wat
3、er andwaste water. It is applicable to water and waste water withrelatively low suspended solids (30 mg/L). The practice isapplicable for any size filter greater than 100 mm (4 in.) indiameter.1.2 This practice can be used to determine the effectivenessof flocculants or coagulants, or both, and filt
4、er medium(a) inremoving suspended and colloidal material from water andwaste water.1.3 Interval between filter backwashing, backwashrequirements, rinse requirements, and effect of filtration rate oneffluent quality can also be obtained with this practice.1.4 The values stated in SI units are to be r
5、egarded asstandard. The values listed in parenthesis are for informationonly.1.5 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determ
6、ine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D1129 Terminology Relating to WaterD2035 Practice for Coagulation-Flocculation Jar Test ofWaterD3370 Practices for Sampling Water from Closed ConduitsD4189 Test Method for Silt Density Index (SDI
7、) of WaterD6698 Test Method for On-Line Measurement of TurbidityBelow 5 NTU in WaterD6855 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 Definitions: For definitions of te
8、rms used in thispractice, refer to Definitions D1129.4. Summary of Practice4.1 A flocculant or coagulant, or both, is added to apressurized flowing water or waste water stream, and the flocthat forms is removed, using a filter medium(a).4.2 The effectiveness of the system in removing suspendedand co
9、lloidal matter is determined by monitoring the quality ofthe filter effluent.4.3 A holding tank for floc formation or floc growth isoptional.4.4 The practice also provides information on intervalbetween filter backwashing, backwash requirements, rinserequirements and effect of filtration rate on eff
10、luent quality.5. Significance and Use5.1 Pressure in-line coagulation-flocculation followed byfiltration is an effective process to remove suspended andcolloidal matter from water and waste water.5.2 The effectiveness of this process is dependent on thetype and concentration of the flocculant or coa
11、gulant, or both,the pH, the temperature, the filtration medium(a), and thefiltration rate. This practice permits the evaluation of thesevarious parameters.5.3 This practice can also be used to determine filterbackwash and rinse requirements.5.4 The results obtained from this practice can be used for
12、plant design of large systems.6. Apparatus6.1 Installation:1This 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 A
13、nalysis, and Surveillance of Water.Current edition approved Jan. 1, 2013. Published February 2013. Originallyapproved in 1982. Last previous edition approved in 2008 as D4188 08. DOI:10.1520/D4188-13.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Servic
14、e at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-29
15、59. United States16.1.1 To prevent contamination by corrosion products, usestainless steel, plastic, or coated (rubber or epoxy-lined) steelfor all wetted parts.6.1.2 Take care to ensure that no contamination will occurfrom oil films on new metal piping, release agents on rawplastic components, or f
16、rom solutions previously used in thesystem. Thoroughly clean or degrease, or both, any materialsthat are suspect.6.1.3 Design all pressurized components based on themanufacturers working pressure rating. Review the manufac-turers rating for compliance with standard engineering prac-tice.6.1.4 Assemb
17、le the system as shown in Fig. 1. The holdingtank just preceding the filter is optional. Use a manual flowcontrol valve to regulate the filter effluent flow.NOTE 1Since the filter is intended to be operated at constant flow withdifferential pressure changes across the filter, manual flow adjustments
18、may be required periodically. For streams that yield a high filter loadingrate, an automatic flow control valve might be required.NOTE 2If a holding tank is used, it should be designed to obtainuniform flow to minimize stagnant zones and to keep the floc suspended.It should also be sized to obtain t
19、he desired retention and contain an airvent.6.1.5 Operate the apparatus by drawing water from thewater supply and pumping it through the system under pres-sure. Use a gage pressure of 275 to 345 kPa (40 to 50 psi) asthe filter inlet pressure.NOTE 3If the water supply is already sufficiently pressuri
20、zed, thepressurizing centrifugal pump is not required.6.1.6 Use a single calibrated pressure gage equipped with a“quick-connect” fitting to measure the filter inlet pressure andfilter pressure drop. Individual gages are also satisfactory butnot as reliable as a single “quick-connect” pressure gauge.
21、6.1.7 Use either a flowmeter or a calibrated volume con-tainer and stopwatch to measure the filter effluent flow.6.1.8 Use an accurate metering pump to inject the flocculantor coagulant, or both. Use an injector with a check valve andlocate the teat of the injector in the center of the flowing strea
22、mand in the vertical position.6.1.9 Use a calibrated volume container and stopwatch tomeasure the injection pump rate.NOTE 4If the suction line of the metering pump is placed into thevolume container, it is necessary to subtract the volume displaced by thesuction line.6.1.10 With small inside diamet
23、er piping (12-in. nominal),use five or six right-angle elbows for mixing. With large insidediameter piping, use in-line static mixing to obtain goodmixing.6.1.11 Valve the filter so the raw water supply can be usedfor backwashing.6.1.12 To protect the pump, install a flow-sensor switch toshut the sy
24、stem down if the water supply to the pump isinterrupted.NOTE 5If a centrifugal pump is used, excessive pressure is usually noproblem provided the pump or piping or both are properly sized. Either ahigh-pressure limit control switch or a pressure-relief device can beinstalled after the pump, if there
25、 are any doubts about excessive pressure.6.1.13 If the system pressure fluctuates by more than6 35kPa (65 psi), install a pressure regulator immediately down-stream of the pressure control valve.6.2 To minimize wall effects, use a filter with a minimumdiameter of 100 mm (4 in.).7. Reagents7.1 For a
26、list of typical coagulants and the preparation ofpolyelectrolyte solutions, refer to Practice D2035.8. Procedure8.1 Start-Up Procedure:8.1.1 First, backwash the filter with the supply water tothoroughly clean the filter medium. Use the backwash raterecommended by the filter medium supplier, which is
27、 usually20 to 50 m3/(hm2) of filter area (8 to 20 gal/(minft2).FIG. 1 Typical Pressure In-Line Coagulation-Flocculation Filtration SystemD4188 132Backwash the filter until the turbidity (as determined by TestMethod D7315) of the backwash is equal (within 10 %) to theturbidity of the supply water. Fo
28、r all sampling follow theprocedure given in Practices D3370.NOTE 6New medium usually contains many fines which need to beremoved for the best filter performance. During backwash approximately2 to 3 % of the medium can be siphoned off at the top of bed to removefines.8.1.2 After backwashing, operate
29、the filter in the servicemode and adjust the flow rate and pressure by adjusting boththe flow control valve and the pressure control valve.8.1.2.1 Set the inlet pressure to the filter at a gage pressureof 275 to 345 kPa (40 to 50 psi).8.1.2.2 Set the flow rate based on filter medium suppliersrecomme
30、ndation, which is usually 5 to 15 m3/(hm2) of filterarea (2 to 6 gal/(minft2).8.2 Operating Procedure:8.2.1 To determine the effectiveness of the filter medium inremoving colloidal and suspended particles with addition offlocculants or coagulants, or both, proceed to 8.2.3. To deter-mine the ability
31、 of the filter medium in removing colloidal andsuspended particles without addition of flocculants orcoagulants, or both, operate the filter for 30 min. Then,measure the water quality of the filter effluent and compare itto the quality of the supply water. Where possible measure theturbidity of the
32、filter effluent on line using Test Method D6698,otherwise use Test Method D6855 or D7315 to measure thewater quality. Repeat the water quality measurements every 30min until results indicate equilibration of the filter.8.2.2 Repeat 8.1.1 and 8.1.2.8.2.3 Start the flocculant or coagulant injection pu
33、mp toinject a previously prepared solution. Initially, set the injectionpump rate to obtain 2 mg/Lof the flocculant or coagulant in thesupply water.8.2.3.1 Set the concentration of flocculant or coagulant inthe supply water using the injection pump curves (pumpingrate against back pressure), concent
34、ration of flocculant orcoagulant in the chemical feed tank, and the flow rate of waterthrough the filter. For example, for a 250-mm (10-in.) diameterfilter operating at 3.785 L/min (1 gal/min) and a polyelectrolytefeed solution concentration of 200 mg/L, the injection pumpshould be adjusted to the f
35、ollowing rate to obtain 2 mg/L in thesupply water: Dilution of polyelectrolyte feed solution of 100to 1 will give 2 mg/L.Therefore,3.785 L/min.!/X L/min! 5 100X 5 0.03785 L/min 5 37.85 mL/minTherefore, set injection pump rate at 37.8 mL/min.8.2.3.2 If polyelectrolyte from supplier is a liquid, assum
36、e100 % active ingredient.8.2.4 After the injection rate has been set, measure theinjection rate (see 6.1.9).8.2.5 Allow 5 min of operation to equilibrate the mixingsection then obtain a water sample just after the mixing sectionand measure the zeta potential, if applicable.NOTE 7For most natural wat
37、ers, optimum coagulation-flocculationwill occur at a zeta potential of 0 6 2 mV. Zeta potential measurementsare only useful for cationic polyelectrolytes and inorganic coagulants(alum and iron). If a nonionic or anionic polyelectrolyte is used, omit thezeta potential measurement.NOTE 8For waters wit
38、h high total dissolved solids, for example,seawater, zeta potential measurements are not meaningful.8.2.6 Adjust the concentration of flocculant or coagulant, orboth, either up or down to obtain the desired zeta potential.8.2.7 After the desired zeta potential has been obtained,allow the system to o
39、perate for 15 to 20 min, and then measurethe filter effluent water quality and compare to the supply waterquality (before flocculant or coagulant, or both, addition) usingturbidity, suspended solids, or silt density index. Repeatmeasurements (both effluent water quality and zeta potential)every 30 t
40、o 45 min until equilibration of the system hasoccurred.8.2.8 If the desired zeta potential value is unknown or if zetapotential measurements are not made, then the coagulantconcentration must be varied and equilibrated values of theeffluent water quality obtained at each concentration to deter-mine
41、the optimum concentration, that is, that concentration offlocculant or coagulant, or both, which gives acceptableeffluent water quality.NOTE 9Exercise care since excess coagulant or flocculant, or both,can be adsorbed by the filter medium, and several hours may be requiredbefore true equilibration o
42、f the system occurs.8.2.9 Measure the pH and the temperature of the filtereffluent for future reference.NOTE 10For some coagulants, for example, alum, the pH is animportant parameter and control of the pH within certain limits is usuallydesirable.8.2.10 In operating the system, periodically measure
43、andmake appropriate adjustment of the filter inlet pressure, filterflow rate, and injection pump rate.8.2.11 To determine the effect of filtration rate on effluentwater quality, repeat 8.1.1 to 8.2.9 but set the flow rate in8.1.2.2 at different values.8.2.12 To determine the effect of different floc
44、culants orcoagulants, or both, on the effluent water quality, repeat 8.1.1to 8.2.9, using different flocculants or coagulants, or both.8.2.13 To evaluate different medium, replace filter or filtermedium with new medium and repeat 8.1.1 to 8.2.9.8.2.14 To determine the need for backwashing for a give
45、nmedium, and flocculant or coagulant, or both, operate thesystem as in 8.2.7 for extended time periods and monitor theeffluent quality. When the effluent quality deteriorates or whenthe pressure drop across the filter reaches the suppliersrecommended maximum limit, backwash the filter.NOTE 11The int
46、erval between backwashings can vary from a fewhours to several weeks, depending on the quantity of suspended andcolloidal material in the supply water, the filter flow rate, the type offlocculant or coagulant, or both, used, and the filter design.8.2.15 To determine the filter rinse time, first dete
47、rmine theoptimum concentration of flocculant or coagulant, or both, at agiven filter flow rate. Then backwash the filter as in 8.1.1.Afterbackwashing operate the filter in the service direction with theaddition of the optimum flocculant or coagulant, or both,D4188 133concentration and monitor the ef
48、fluent water quality versustime to obtain acceptable water quality. Depending on thedesired water quality and nature of colloidal material in thesupply water, the rinse time can vary from 15 min to severalhours.8.3 Shutdown Procedure:8.3.1 Shut off the injection pump and push the stop buttonon the p
49、ressurizing pump motor.8.3.2 Allow the pressure to reach zero before disconnectingthe system or carrying out maintenance on the piping system.9. Calculation and Report9.1 Report the following data and information:9.1.1 Filter medium(a), depth of medium, filter area, filterflow rate, filter backwash rate, filter rinse rate, rinse time,backwash time, time between backwashings (service run time),pressure of filter influent, and pressure drop across filter duringservice run.9.1.2 Flocculant or coagulant, or both used, concentration offlocculant or coagulant, or
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