ASTM_D_6161_-_19.pdf

Designation:D616119Standard TerminologyUsed for Microfiltration,Ultrafiltration,Nanofiltration,andReverse Osmosis Membrane Processes1This standard is issued under the fixed designation D6161;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 terminology covers the use of microfiltration,ultrafiltration,nanofiltration,and reverse osmosis for mem-brane separation processes.1.2 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade(TBT)Committee.2.Referenced Documents2.1 ASTM Standards:2D1129 Terminology Relating to WaterD2035 Practice for Coagulation-Flocculation Jar Test ofWaterD3739 Practice for Calculation and Adjustment of theLangelier Saturation Index for Reverse OsmosisD4582 Practice for Calculation and Adjustment of the Stiffand Davis Stability Index for Reverse Osmosis(With-drawn 2019)33.Summary3.1 This terminology is common to membrane separationprocesses but independent of the source of manufacture.4.Significance and Use4.1 The need to understand the relationships found inmembrane unit processes for water treatment increases with thecontinuing demand for these separation systems.Defining theterms common to microfiltration,ultrafiltration,nanofiltration,and reverse osmosis processes assist the manufacturer,consultant,and end-user in eliminating inter-process terminol-ogy confusion.This standard expands the definitions found inTerminology D1129.5.Terminology5.1 Definitions:absolute filter rating,nparticle size above which 100%ofparticles that are trapped on or within the filter medium.absorption,nthe release for desorption holding of a sub-stance within a solid by cohesive or capillary forces.accumulator,na pulsation dampener installed on the suctionand/or discharge lines of pumps,generally plunger type,tominimize pressure surges and provide uniformity of flow.accuracy,nthe closeness of agreement between an observedvalue and an accepted reference value.Where an acceptedreference value is not available,accuracy is a description ofa measure of the degree of conformity of a value generatedby a specific procedure to the assumed or accepted truevalue,including both precision and bias.acidity,nthe quantitative capacity of aqueous media to reactwith hydroxyl ions.activated carbon,ngranulated or powdered activated carbonused to remove tastes,odor,chlorine,chloramines,and someorganics from water.A family of carbonaceous substancesmanufactured by processes that develop adsorptive proper-ties.adsorption,nthe holding of a substance onto the surface ofa solid by chemical surface forces,without forming newchemical bonds.aerobic bacteria,nbacteria that require oxygen for growth.See bacteria,aerobes.aggregate,ngranular material such as sand,gravel,crushedstone.aggressive water,nwater having a high tendency to corrodepipes and other equipment.Usually seen as having anegative Langelier Index value.1This terminology 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 1,2019.Published July 2019.Originally approvedin 1997.Last previous edition approved in 2010 as D6161 10,which waswithdrawn January 2019 and reinstated in July 2019.DOI:10.1520/D6161-19.2For 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.3The last approved version of this historical standard is referenced onwww.astm.org.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade(TBT)Committee.1 air header,nthe pipe running within a cassette that distrib-utes the air to the individual modules or aerators.air scour,ndistributing air over the entire area at the bottomof a filter media flowing upward or immersed membrane toimprove the effectiveness of filtration or backwashing or topermit the use of lower backwash water flow rate,or both.air stripping,vremoval of volatile substances from a watersolution by passing a gas through the solution.algae,na major group of lower plants,generally aquatic,photosynthetic of extreme