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57 3 Vol.57 No.3 20063 Journal of Chemical Industry and Engineering (China) March 2006、(Ⅰ)姬朝青,陈 浩(,313000):;;;:TQ028.8 :A:0438-1157(2006)03-0601-06PhysicalchemistrystudyonROandNFprocess(Ⅰ)EquationsofsoluterejectionandsolutionpermeationfluxonporousmembraneJIChaoqing,CHENHao(ZhejiangStoneEnvironmentEngineeringCo.Ltd,Huzhou313000,Zhejiang,China)Abstract:Theequationsofsoluterejectionandsolutionpermeationfluxofmulti-solutesolutiononporousmembranewerederivedonthebasisoftheadsorption-diffusionmodel.Thephysicalsignificanceofparametersintheequationswasdiscussed.Fromtheequationsofsoluterejectionandsolutionpermeationfluxonporousmembrane,thefollowingconclusionswerereached:whenthesolventwasadsorbedpreferentiallyonthemembranesurface,soluterejectioncoulddecreaseasthemembraneporosityincreased;whenthesolutewasadsorbedpreferentiallyonthemembranesurface,threecurvesofsoluterejectionvs.membraneporositywereobtained;soluterejectioncoulddecreaseasmembraneporousrateincreased;aminimumvaluewasshownonthecurveofsoluterejectionvs.membraneporousrate;aminvalueandamaxvaluewasshownonthecurveofsoluterejectionvs.membraneporosity.Thesolutionpermeationcoefficientdependedonthesolutediffusioncoefficientanddiffusionselectivityofsolutewithsolventinthemembranephase.Membranefoulingwascausedbythefactthatthesolutewasadsorbedpreferentiallyonthemembranesurface,leadingtoincreasedmembranesurfaceresistanceanddecreasedsolutionpermeationcoefficient.Keywords:reverseosmosis;nanofiltration;adsorption-diffusion;membranefouling 2005-01-10,2006-01-16.:(1963—),,. -、、Sourirajan-[1-3].-,,. Receiveddate:2005-01-10.Correspondingauthor:JIChaoqing.E-mail:Jichaoq-cn@sina.com ,-[4].,.-,,.1 1.1 、、,、、、.、,、,、,、.2、..,、,Langmuir.[4],nLiXfiL=KiXiL1-∑1-KiXiL(1)i.iFfi=-VidpLdL+RTXfi(L)dXfiLdL+ZiFdΧLdL(2)Ffw=-VwdpLdL-RT1-∑XfiLd∑Xfi(L)dL(3)iFsi=-VidpLdL+RTXi(L)dXiLdL+ZiFdΧLdL(4)Fsw=-VwdpLdL-RT1-∑XiLd∑XiLdL(5)[4]:,Jsv=usw=usiJfv=ufw=ufi.[4],iJfvi=-DimViRTdpLdL+1XfiLdXfiLdL+ZiFRTdΧLdL(6)Jfvw=-DwmVwRTdpLdL-11-∑XfiLd∑XfiLdL(7)Jsvi=-ViRTdpLdL+1XiLdXiLdL+ZiFRTdΧLdL(8)Jsvw=-VwRTdpLdL-11-∑XiLd∑XiLdL(9),i=1,…,n;Zii,,Zi,,Zi;i,Zi=0,i.L=0,Xi0=Xi2, Xfi0=KiXi21-∑1-KiXi2,p0=p1L=δ,Xiδ=Xi3, Xfiδ=KiXi31-∑1-KiXi3,pδ=p2i,Zi=Z+,j,Zj=-Z-,(6)i、jJfvi=-DimViRTdpLdL+1XfiLdXfiLdL+Z+FRTdΧLdL(10)Jfvj=-DjmVjRTdpLdL+1XfjLdXfjLdL-Z-FRTdΧLdL(11)(8)i、jJsvi=-DiViRTdpLdL+1ViLdXi(L)dL+Z+FRTdΧLdL(12)Jsvj=-DjVjRTdpLdL+1XjLdXjLdL-Z-FRTdΧLdL(13)(10)～(13)Nernst-Planck.(10)、(11)602 57 ijJfvij=-DijmVijRTdpLdL+dlnXfiLZ-Z++Z-XfjLZ+Z++Z-dL(14)(12)、(13)ijJsvij=-DijVijRTdpLdL+dlnXi(L)Z-Z++Z-XjLZ+Z++Z-dL(15) Dijm=(Z++Z-)DimDjmZ+Dim+Z-Djm;Dij=Z++Z-DiDjZ+Di+Z-Dj;Vij=ViZ-+VjZ+Z++Z-.i,Zi=0,(6)iJfvi=-DimViRTdpLdL+dlnXfiLdL(16)(8)iJsvi=-DiViRTdpLdL+dlnXiLdL(17)1.2 Jv=1-Jfv+Jsv(18)ijiXpij=XZ-Z++Z-fi3XZ+Z++Z-fj31-Jfv+XZ-Z++Z-i3XZ+Z++Z-j3JsvJv(19) Xpij=XZ-Z++Z-piXZ+Z++Z-pj.Xpi=Xfi31-Jfv+Xi3JsvJv(20)(14)～(17),Xfiδ=Xfi3=KiXi31-∑1-KiXi31-∑1-KiXi31-∑1-KiiXi2=exp-JsvδDij+JfvδDijm(21)1-∑1-KiXi31-∑1-KiiXi2=exp-JsvδDi+JfvδDim(22)(7)、(9),(7)、(9)、(21)、(22)(18)Jfvij=JvBij(23)Jfvi=JvBi(24)Jsvij=JvDijβijDijmBij(25)Jsvi=JvDiβiDimBi(26):βij=1-DijmDwm1-DijDw;βi=1-DimDwm1-DiDw;Bij=1+DijDijmβij-1;Bi=1+DiDimβi-1.(7)、(9),Xfiδ=Xfi3=KiXi31-∑1-KiXi3(21)、(22)、(18),Jv=AΔp-RTVwln1-∑Xfi31-∑Xi2-RTVwln1-∑1-KiXi2(27),A=VwDwmRTδ1+DwDwm-11-Dwβij-1DijmBijA=VwDwmRTδ1+DwDwm-11-Dwβi-1DimBi(23)、(25)(24)、(26)(14)、(15)(16)、(17),(19)(20)ijRij=1-Kij-Dijβij1-exp-Jvβij-1δDijmBij1-∑(1-Ki)Xi2DijmBij1-∑1-KiXi2Mijexp-JvδDijmBij+VijΔpRT(28) Kij=Kij+DijβijDijm-KijBij;Kij=KZ-Z++Z-iKZ+Z++Z-j.i603 3 :、(Ⅰ)Ri=1-Ki-Diβi1-exp-Jvβi-1δDimBi1-∑(1-Ki)Xi2DimBi1-∑1-KiXi2Miexp-JvδDimBi+ViΔpRT(29) Ki=Ki+DiβiDim-KiBi.AB,A+B-,Ka,α,ABX(1-α),(28)Ka=A+B-ABAB:XpAXpB=(1-RA+B-)2KaVw×X(1-α).(29)AB:XpAB=(1-RAB)(1-α)X.Ka=XpAXpBVwXpAB(1-RAB)=(1-RA+B-)2.XpA=XpB,ABRt=1-XpA+XpBX =RAB+α1-RAB-KaVw1-α1-RABX(30)(18)、(23)、(25)JvXiLZ-Z++Z-Xj(L)Z+Z++Z--XZ-Z++Z-i2XZ+Z++Z-j2Kij-Dijβij∑1-KiXi2DijmBij1-∑1-KiXi2=DijdXiLZ-Z++Z-Xj(L)Z+Z++Z-dL,ijMij=XZ-Z++Z-i2XZ+Z++Z-j2XZ-Z++Z-i1XZ+Z++Z-j1=expJvkij1+Kij-DijβijDijmBij∑1-KiXi21-∑1-KiXi2expJvkij-1(31)(18)、(24)、(26)Mi=expJvki1+Ki-Diβi∑(1-Ki)Xi2DimBi1-∑1-KiXi2expJvki-1(32)nijN..2 2.1 2.1.1 Kij()、Ki()和βij、βi的物理含义 (25)、(26):βij、βi、.(28)、(29):Kij()、Ki()、.Kij1Ki1,,Kij()1,Ki()1,Kij()、Ki().Ki1,,Ki()1,.2.1.2 多孔膜的分离机理 (28)、(29),、,、,、,.、.-、,,.、,、.Sourirajan[3]-.2.1.3 溶质脱除率随膜孔隙率的变化规律 ,,M=1,,(27)(29).(29)604 57 dRid=DiβiDimB2iKi1-Jvδ1-1-DimDiβi1-BiJvdJvdDimBi-1+JvδβiDiβiDim-11-BiJvDiβiDim-1dJvdDimBiexp-Jvβi-1δDimBiexp-JvδDimBi,Ki1,,(22)、(24)、(26)exp-Jvβi-1δDimBi1,:dRid0,.,Ki1,dRid=0,e2Ri20,;e2Ri20,;e1e2,e12Ri20,e22Ri20,.CA()[3].2.1.4 弱电解质的溶质脱除率和电离度的关系 (30),..(30)CA[5].2.2 2.2.1 对溶液体积通量方程的讨论 (27),A、,A.A0=VwDwmRTδ×1+DwDwm-1.2.2.2 膜污染机理的讨论 (27):,,Ki1,,,,RTVwln1-∑1-KiXi2,..(27)(29):①,,;②,,.(30)、(27):,pH,,,.3 (27)～(29):.(1),,.(2),、,.、..4 ,,、..605 3 :、(Ⅰ). A,A0———,m3m-2s-1MPa-1Bij,Bi———Di,Dj,Dij———i、jij,m2s-1Dim,Djm,Dijm———i、jij,m2s-1Dw,Dwm———,m2s-1F———Faraday,Cmol-1Fsi,Fsw,Ffi,Ffw———i、,NJfv,Jsv,Jv———、,m3m-2s-1Ka———,m3mol-1