ASTM_D_6157_-_97_2011.pdf

Designation:D615797(Reapproved 2011)Standard Practice forDetermining the Performance of Oil/Water SeparatorsSubjected to a Sudden Release1This standard is issued under the fixed designation D6157;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 describes the testing procedure,any nec-essary related apparatus,and the sampling technique to be usedin determining the performance characteristics of an oil/waterseparator subjected to the sudden release of a relatively largequantity of hydrocarbons that may appear in its influent in pureform or at high concentration.1.2 This practice does not address the determination of theperformance characteristics of an oil/water separator subjectedto surface run-off resulting from rain water draining fromimproved or unimproved land.In this case,refer to PracticeD6104.1.3 This practice does not address the determination of theperformance characteristics of an oil/water separator subjectedto a mechanically emulsified influent such as provided by apump.1.4 This practice does not investigate the ability of theseparator to handle debris or suspended solids,that is,grit ortree leaves.1.5 While the effluent may meet code requirements for totaloil and grease content,this practice does not address thepresence of soluble organics,that is,benzene,toluene,ethyl-benzene and xylene(BTEXs)that may be detected in theeffluent.It also does not make any provisions for the effects ofdetergents,surfactants,soaps or any water soluble matter(thatis,salts)or any portion of an essentially insoluble matter thatmay be found in solution on separation.(Effects of certainwater soluble chemicals or solids may be investigated byadding them to the water at predetermined constant concentra-tions.)1.6 In order to estimate the effect of water temperature onthe performance of the separator,the tests described in thispractice must be performed at two water temperatures.Theselected temperatures must be at least 10 C(18 F)apart,withthe temperature ranging from a minimum of 0 C(32 F)to amaximum of 50 C(122 F).1.7 This practice does not make any provisions for thevariation of pH or temperature during a test run.Refer toAppendix X1 for further detail.1.8 This practice can be used with a variety of hydrocar-bons.It adopts No.2 fuel oil with a density2of 845 kg/m3(52.73 lbm/ft3)and a viscosity2of 1.9 to 4.1 centistokes at40 C(104 F)and SAE 90 lubricating oil with a density(SeeSAE J313)of 930 kg/m3(58 lbm/ft3)at 15.5 C(60 F)and aviscosity(See SAE J306)of 13.5 to 24 centistokes at 100 C(212 F)as the comparative testing media.It is understood thatthe results obtained from this practice are only directlyapplicable to No.2 fuel oil and SAE 90 lubricating oil for thetested concentrations and only careful interpolation or extrapo-lation,or both,is allowed to other hydrocarbons.Low viscosityor high density hydrocarbons or hydrocarbons that contain alarger fraction of highly soluble compounds may need to betested separately.NOTE1No extrapolation outside the range of the tested influent oreffluent oil concentrations is allowed as performance may not be linear.Hence,to establish performance at a higher or lower concentration,theseparator shall be tested for that specific condition.In addition,linearitymust be established prior to using linear interpolation.1.9 Since regulations are based on effluent total hydrocar-bon content,this practice does not set forth any lower limits onoil particle size for the evaluation of separator efficiency.However,a standardized means for mixing oil and water shallbe specified to ensure repeatability.It must be noted howeverthat smaller particles,having a greater surface area to volumeratio,rise at a slower rate than their larger counterparts.(GuideF933 requires that 20%of all oil particles be smaller than orequal to 50 m and IMO MEPC 60(30)does not mention anyparticle size requirements but asks the user to avoid emulsioncausing chemicals.)1.10 Although the tests described in this practice intend tosimulate the performance of a separator subjected to a suddenrelease,they do not cover all possible applications.It is the end1This practice is under the jurisdiction of ASTM Committee D19 on Water andis the direct responsibility of Subcommittee D19.06 on Methods for Analysis forOrganic Substances in Water.Current edition approved May 1,2011.Published June 2011.Originallyapproved in 1997.Last previous edition approved in 2003 as D6157 97(2003).DOI:10.1520/D6157-97R11.2Ray E.Bolz and George L.Tuve,CRC Handbook of tables for AppliedEngineering Science,2ndEdition,CRC Press,1991.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 users responsibility to determine whether his separation re-