Complexfluids and applicationsin the process industries...
Transcript of Complexfluids and applicationsin the process industries...
Complex fluids and applications in the processindustries: fluid homogenization and transport
Tuomas Koiranen / LUT, Finland
Introduction to complex fluids problematics(Definitions, classification), rheologiesprocess conditions in applications and typicalprocess equipment
Complexfluidsdefinitions:1)Fluidsshowingnon-linearviscousbehaviour,aswellasviscoelasticmaterials,areComplexFluids.(Complexfluidsengineeringlaboratory,UniversidadHuelva,Spain)
2)Typicallymulticomponent systems,complexfluidsarehighlynonlinearwithrespecttocomposition changes,andoftenthefluidstatesthatprovidethedesiredmechanicalorchemicalpropertiesaremetastableandaccessibleonlythroughpreciselycontrolledprocessingandformulationsteps.(CarnegieMellon,CenterforComplexfluidsEngineering)
- SummaryofDefinitions:Complexfluidshave2ormorefluidphaseswhichhavephysicalinteractionwitheachother,andtheycanhavetypicallyacomplexmicrostructure.Fluidphasesrefertodispersesystems.
Classificationofdispersesystems
Liquid-gas: foams,gas-liquiddispersionsGas-liquid: fog,liquidaerosolsGas-solid:solidaerosols,powdersSolid-gas: solidfoamsLiquid-liquid: liquid-liquid dispersions ,emulsionsSolid-liquid: gels,pastesLiquid-solid: solid-liquid suspensions,slurries, sols
(BjörnLindman,SurfactantsandCellulosepolymersinaqueoussolutions-course,Physicalchemistry,LundUniversity,Sweden,2013)
Continuo
usm
edium
Dispersedphase GAS LIQUID SOLID
GAS None Liquidaerosol(fog,hairsprays)
Solidaerosol(airparticles,
smoke)LIQUID Foam
(whippedcream,shavingcream,flotationcell
foam)
Emulsion(milk,
mayonnaise,lotions,
ointments)
Sol(blood,
pigmentedink,fibersuspensions)
SOLID Solidfoam(aerogel,polymerfoam,pumice)
Gel(agar,gelatinjelly)
Solidsol(gemstone,jewel)
Bulkrheologies(EKATOMixinghandbook,2000)- Themacroscalefluidrheology
Bulkrheologies- Themacroscalefluidrheology
Sol-gelviscosityexampleasafunctionofshearrateatdifferenttemperatures.Gellingat20°Ccurve.
Bulkrheologies- Themacroscalefluidrheology
Solutionrheologyexample:Sol-geltransition
Illustrationoftheviscoelasticstructureandgelationphenomenonatelevatedtemperature. (Metzger2011,Kalanti2015)
Microrheology(Rep.Prog.Phys.68 (2005)685,J.Non-NewtonianFluidMech.112 (2003)237).
1) Microrheologyisconcernedwithhowmaterialsstoreanddissipatemechanicalenergyasafunctionoflengthscale.
2) Itiscloselyconnectedtothefieldofmicrofluidics(inkjetprinting,microreactors,valvesetc.)
3) Classification(Waigh2005)
1) Largeamplitudeoscillatoryshear(LAOS)behaviorstudiesofcomplexfluidsinformingmicrostructures.
TypeI.Strainthinning:mostpolymersolutionsormeltsTypeII.Strainthickening: iondipolesorhydrogenbonding(PVA+Na2B4O7,alcohol+claywithwaterbridge)TypeIII.Weakstrainovershoot:surfactantsolutions,biopolymers(dough),liquidemulsionsTypeIV.Strongstrainovershoot:HASEpolymers(acid/acrylatewithethoxylatedhydrophobe)
Microstructures(Quemada,1997)
Requiredshearratesindifferentapplications
Process Shearrate,1/s ApplicationParticlesedimentationinsuspension 1E-6-1E-3 paints,medicines
Extrusion,pipeflow 1-1E+3 food,polymersMixinginstirredtank 10-1000 food,chemicals
Spraydrying 1E+3-1E+5 food,chemicalsHighspeedcoating 1E+4-1E+6 paper
Typicalshearratesofdifferentprocesses(Fried,1995;Pauletal.2004;Kessler,1998)
MixingpowerforProductionofO/Wdispersions(Paulet.al,2004)
Emulsions(JohnTexter,PracticalSurveycourseonsmallparticleformation,StriderRes.Co.2009)- Emulsionsareunstablebutmicroemulsionsarestable.- Criticalmicelleformingconcentration
+chargedSmalltolongchain
- chargedlongtosmallchain
Mesophases(JohnTexter,PracticalSurveycourseonsmallparticleformation,StriderRes.Co.2009)
Microstructureformation(Lindman,2013)
PARTICLESTABILIZATION- Hardwallandelectrostaticrepulsion,andVanderWaalsattractionforcesdefinetheelectrostaticstabilizedcolloids
-Instericstabilizationpolymerchainsformsterichindranceforparticlestoformaggregates
MixersforcomplexfluidsStaticmixers- Largevarietyoffluidsmixing
(Laminar/Turbulent,S/L/G)
- Shortresidencetimes(τc)
- Largeshearrateregionanddispersedphase/continuousphase–ratios(Rµ)basedondifferentgeometries
- Simplesizingprocedures(pump)P = ∆𝑝𝑄
MixersforcomplexfluidsMixingtanks- Largeresidencetimeregions- Largedistributionsofshearrates- Liquids,emulsions,gels,pastes
Somespecialcases- Ultrasonicationcanbeused
foremulsification,difficultslurryformations(e.g.nanomaterialwetting).
- Electrocapillarity:Internalphasebreaksintoemulsiondropletincontinuousphasewhenelectricpotentialdifferenceisappliedbetweenphases(Watanabeetal.,1978)
- Initialdispersionispressedthroughporousmembranetoformemulsion(Omietal.,1994).
Summaryofhomogenizationmethods
- Complexfluidscanalsobepresent inchangingprocessconditions:Chemicalreactions,crystallizations,meltingprocessesetc.
Typeofcomplexfluids MixersusedPaints rotor-stators,stirredtanks(shearingaction)Adhesives kneaders,rotor-statorsPaintpastes rollmills,ballmills,tubemills,rotor-stators
Greasesstirredtanks(dualaction),kneaders(sigmablade,dispersionblade)
Ceramics(heavyconsistency)
panmixers,pugmills,planetarymills
Fibrousmixeskneaders,sigma/dispersionblade),intensivemixers(Banburytype)
Resins(heavyconsistency)
kneaders,rollmills,intensivemixers(Banbury,rotor-stator)
Rubbers&Elastomers(stiffgels)
intensivemixers,rollmills,kneaders
Mineralslurriesstirredtanks(dualaction),in-linemixers(rotor-stators)
Emulsions(food,cosmetics,pharma)
paddlestirredtanks,staticmixers,in-linemixers(rotor-stators),pressurehomogenizer
Foams(gas-liquid) Gas-liguidInjectors,stirredtanks
Complexfluidstransport- Centrifugalpumpsarethemostcommonpumpsforfluidtransport- Theproblemsarisetypicallyfor- 1)shearthickeningfluids=>viscosityincreases=>flowratedecreases- 2)highsolidcontents=>materialabrasion- 3)preservingfluidmicrostructure=>shearratechangesoccur- Specialpumpscanbeusedincomplexfluidstransport:peristaltic
pumps,positivedisplacementpumpslikeeccentricscrewpumps(e.g.FlowroxLtd)
Literature:Equipment
EKATOHandbookofMixingTechnology,EKATORühr- undMischtechnikGmbH, 2000
Matijevic,E.,Good, R.J.(eds.),Surfaceandcolloid scienceVol13,Ch.1:Electrochemistry ofoil-water interfaces, Springer, USA,1984
McDonough,R.J., MixingfortheProcess Industries, VanNostrand Rheinhold, NewYork,USA,1992
Paul,L.E.,Atiemo-Obeng,V.,Kresta, S.,(eds.),Handbookofindustrial mixing,Wiley,2004
Pehrman, N.,Slurryflowsinprogressivecavityandperistaltic hosepumps, LUT2014
Thakur,R.K.etal.,Staticmixers intheprocess industries - areview,TransIChemE81A,(2003)787-826
Grace,H.P.,ChemEngCommun14(1982),225–277
Zlokarnik,M.,Judat,H.,Ullmann's EncyclopediaofIndustrial Chemistry, Vol.B2.,Ch.25:Stirring ,VCHVerlagsgesellschaftGmbH, Germany,1988
Literature:Processes
Florence, A.T.,Attwood,D.(eds.),Physicochemical principles ofpharmacy,Pharmaceuitical press,UK, 2011
Dickinson, E.,Leser, M.(eds.),Foodcolloids – self-assemblyandmaterialscience, RSCpublishing, UK, 2007
Fried,J.R.,Polymerscienceandtechnology, Prentice Hall,USA,1995
Kessler, H.G.,Foodandbioprocessengineering – dairytechnology, VerlagA.Kessler,Germany,1998
Mixinginpolymerprocessing, Rauwendaal,C.(ed.),MarcelDekker,USA,1991
Omi,S.,Katami,K.,Yamamoto,A.,Iso,M.,Synthesisofpolymeric microspheres employingSPGemulsification technique, J.Appl. Polym.Sci.51(1994)1-11
Watanabe,A.etal.,J.Colloid InterfaceSci64(1978)278
Literature:Complex fluids, dispersesystems,rheologyandmicrorheology
Chen, D.T.etal.,Rheological microscopy:localmechanicalproperties frommicrorheology, Phys.Rev.Lett.90(2003)108301-1- 108301-4
Lindman, B.,Surfactantsandcellulose polymersinaqueoussolutions (course material),PhysicalChemistryDept.,Lund University,Sweden,2013.
Luckham,P.F.,Rossi,S.,Thecolloidal andrheological properties ofbentonite suspensions, AdvancesinColloid andInterfaceScience82(1999)43-92
Texter, J.,Practical surveycourseonsmallparticle formation (coursematerial), StriderResearch Company,USA,2009
Quemada,D.,Rheological modelling ofcomplex fluids.I.Theconceptofefectivevolumefraction revisited,Eur.Phys.J.AP1(1998)119-127
Quemada,D.,Berli, C,Energyofinteraction incolloids anditsimplications inrheological modeling,AdvancesinColloid andInterfaceScience98(2002)51-85
Gelbart, W.M.,Ben-Shaul,A.,The“New”Scienceof“Complex Fluids”, J.Phys.Chem.100(1996)13169-13189
Waigh,T.A.,Microrheologyofcomplex fluids, Rep.Prog.Phys.68(2005)685–742
Sim,H.G.,Ahn,K.H.,Lee,S.J.,J.Non-Newtonian FluidMech.112(2003)237–250
MezgerT.TheRheologyHandbook.3rdEdition, VincentzNetwork, 2011.
KalantiA.2014.Basicsofrheology(course materialinFinnish), AntonPaar.Imatra,Finland,2015.
Someresearchquestions
1)Istheresponseofoneprobeparticleatruemeasureofthebulkrheology?Aninterconnectionofmicrostructurestobulkrheologyiswelcome.
2)Theequipment selectionandsizingarebasedondynamicviscositydata.Elasticandviscousmodulidataareavailableforavastamountofdifferentcomplexfluidsystems.Focusalsofordynamicrheologymeasurements.
3)Complexfluidstructuresformation.Systematic,uniformandtechno-scientificapproachforproductdesign?e.g. formationenergies,characteristicresidencetimes,criticalsurfaceareas,etc.
THANKYOU/KIITOS