ASTM_D_3230_-_13.pdf

Designation:D323013Standard Test Method forSalts in Crude Oil(Electrometric Method)1This standard is issued under the fixed designation D3230;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.This standard has been approved for use by agencies of the U.S.Department of Defense.1.Scope*1.1 This test method covers the determination of the ap-proximate chloride(salts)concentration in crude oil.The rangeof concentration covered is 0 to 500 mg/kg or 0 to 150lb/1000 bbl as chloride concentration/volume of crude oil.1.2 This test method measures conductivity in the crude oildue to the presence of common chlorides,such as sodium,calcium,and magnesium.Other conductive materials may alsobe present in the crude oil.1.3 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.3.1 ExceptionAcceptable concentration units are g/m3or PTB(lb/1000 bbl).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.For specificwarning statements,see 7.3,7.4,and 7.11.2.Referenced Documents2.1 ASTM Standards:2D381 Test Method for Gum Content in Fuels by Jet Evapo-rationD1193 Specification for Reagent WaterD4928 Test Method for Water in Crude Oils by CoulometricKarl Fischer TitrationD5002 Test Method for Density and Relative Density ofCrude Oils by Digital Density Analyzer3.Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 PTBlb/1000 bbl.3.1.2 salts in crude oilcommonly,chlorides of sodium,calcium,and magnesium dissolved in crude oil.Other inor-ganic chlorides may also be present.4.Summary of Test Method4.1 This test method measures the conductivity of a solutionof crude oil in a mixed alcohol solvent when subjected to anelectrical stress.This test method measures conductivity due tothe presence of inorganic chlorides,and other conductivematerial,in the crude oil.A homogenized test specimen isdissolved in a mixed alcohol solvent and placed in a test cellconsisting of a beaker and a set of electrodes.A voltage isimpressed on the electrodes,and the resulting current flow ismeasured.The chloride(salt)content is obtained by referenceto a calibration curve of current versus chloride concentrationof known mixtures.Calibration curves are based on standardsprepared to approximate the type and concentration of chlo-rides in the crude oils being tested.5.Significance and Use5.1 This test method is used to determine the approximatechloride content of crude oils,a knowledge of which isimportant in deciding whether or not the crude oil needsdesalting.The efficiency of the process desalter can also beevaluated.5.2 Excessive chloride left in the crude oil frequently resultsin higher corrosion rates in refining units and also hasdetrimental effects on catalysts used in these units.5.3 This test method provides a rapid and convenient meansof determining the approximate content of chlorides in crudeoil and is useful to crude oil processors.6.Apparatus6.1 The apparatus(see Annex A1)shall consist of a controlunit capable of producing and displaying several voltage levelsfor applying stress to a set of electrodes suspended in a testbeaker containing a test solution.The apparatus shall be1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products,Liquid Fuels,and Lubricants and is the direct responsibility ofSubcommittee D02.03 on Elemental Analysis.Current edition approved May 1,2013.Published May 2013.Originallyapproved in 1973.Last previous edition approved in 2010 as D3230 10.DOI:10.1520/D3230-13.2For 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.*A Summary of Changes section appears at the end of this standardCopyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 capable of measuring and displaying the current(mA)con-ducted through the test solution between the electrodes at eachvoltage level.NOTE1Some apparatus are capable of measuring voltage and currentinternally and,after comparison to internal calibration curves,of display-ing the resultant concentration.6.2 Test BeakerSee Annex A1.6.3 Pipet,10 mL(total delivery),shall be used in 10.3 and11.1 when the viscosity of the crude oil material beinganalyzed is suitable to transfer the required volume for use inthe test(see 6.3.1).The type of pipet to use is one that is ableto be rinsed to ensure the entir