ASTM_D_8002_-_15.pdf

Designation:D800215Standard Test Method forModified Fouling Index(MFI-0.45)of Water1This standard is issued under the fixed designation D8002;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 test method covers the determination of the modi-fied fouling index(MFI)of water measured at constantpressure.This test can be used to indicate the fouling potentialof reverse osmosis/nanofiltration(RO/NF)feed water dueparticulate matter and is applicable to low and high turbiditywaters.Since the size,shape,and nature of particulate matter inwater may vary,this test method is not an absolute measure-ment of the quantity of particulate matter.1.2 This test method is not applicable for reagent-gradewater Types I,II,and III of Specification D1193 or effluentsfrom most reverse osmosis and ultra-filtration systems.1.3 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.4 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 determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2D1129 Terminology Relating to WaterD1193 Specification for Reagent WaterD2777 Practice for Determination of Precision and Bias ofApplicable Test Methods of Committee D19 on WaterD3370 Practices for Sampling Water from Closed ConduitsD4189 Test Method for Silt Density Index(SDI)of WaterD6161 Terminology Used for Microfiltration,Ultrafiltration,Nanofiltration and Reverse Osmosis Membrane ProcessesD7726 Guide for The Use of Various Turbidimeter Tech-nologies for Measurement of Turbidity in Water3.Terminology3.1 Definitions:3.1.1 For definitions of terms used in this standard,refer toTerminologies D1129 and D6161.3.2 Definitions of Terms Specific to This Standard:3.2.1 modified fouling index,MFI-0.45,nindex calculatedfrom the development of filtration velocity through a 0.45-mmembrane filter.D27774.Summary of Test Method4.1 Water is passed through a 0.45-m membrane filter atconstant pressure of 200 kPa and the development of the rateof filtration is measured continuously.4.2 The MFI is calculated from the obtained data of flowversus time at constant pressure and temperature.5.Significance and Use5.1 This test method is an alternative for the silt densityindex(SDI)method(Test Method D4189)with the aim toovercome inaccuracies related to a nonlinear relation with thefouling potential due to particulate matter concentration,ab-sence of temperature correction,support pad,and time.5.2 The MFI-0.45 can serve as a useful indication of thequantity of particulate matter.5.3 The MFI-0.45 can be used to determine effectiveness ofvarious processes such as filtration or clarification used toremove particulate matter.5.4 The MFI-0.45 has empirically been correlated withfouling tendency of some water treatment equipment such asreverse osmosis(RO)devices.6.Apparatus6.1 MFI AssemblyAs described in Fig.1 and Fig.2,wetted parts should be made of high-quality stainless or plasticto prevent contamination by corrosion products.Do not usereactive materials such as carbon steel,galvanized steel,castiron,and copper alloys.Suitable filter holders,designed towithstand an operational gage pressure of 350 kPa,can beobtained from suppliers of membrane filters.The filter holdershould be equipped with a device releasing air.1This test method is under the jurisdiction of ASTM Committee D19 on Waterand is the direct responsibility of Subcommittee D19.08 on Membranes and IonExchange Materials.Current edition approved July 15,2015.Published August 2015.DOI:10.1520/D8002-15.2For 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 6.2 Membrane Filter:6.2.1 Membrane,white hydrophilic,mixed cellulose nitrate(5075%)and mixed cellulose acetate(MCE).6.2.2 Replaceable Highly Porous Foam Support Pad,to beplaced on the bottom of the filter holder.6.2.3 Mean Pore Size,0.45 m.6.2.4 Diameter,47 mm.6.2.5 Thickness,115 to 180 m.6.2.6 Pure Water Flow,25 to 50 s/500 mL.6.2.7 Pressure Difference across Membrane Filter,200 kPa.6.2.8 Bubble Point,179 to 248 kPa.6.2.9 Use only filters that are packaged in the same orien-tation.6.3 Thermometer or Sensor Suitable for Measuring Tem-perature of the Water Sample,capable of being read orregistered 61C.6.4 Electronic flow meter or mass balance.6.5 Computer o