| 291 | 10 | 386 |
| 下载次数 | 被引频次 | 阅读次数 |
通过对降膜分子蒸馏器蒸发表面上液膜流动和传质传热的分析,建立了液膜的传质和传热方程;并在单组分非线性BGK方程的基础上,建立了描述多组分稀薄气体流动的非线性BGK模型方程。通过适当的边界条件将液膜方程和气体方程耦合在一起,得到了降膜分子蒸馏过程的传质与传热数学模型。该模型揭示了液膜温度和浓度在径向和轴向上的变化规律以及气相空间气体的密度、温度和速度的变化规律,适用于恒壁温和绝热壁等不同操作情况。
Abstract:On the basis of analysis of liquid flow, mass transfer and heat transfer as well as the new scheme for multi-component flow calculations between two closed surfaces of evaporation and condensation, a new mathematic model is developed to describe falling-film molecular distillation process. This model can be used to calculate the profiles of temperature and concentration of film and the profiles of density, temperature and velocity of vapor with the consideration of the feed rate, evaporation temperature and inert gas pressure. The model is applicable to simulate the evaporator with a constant wall temperature or with insulated wall.
[1]XU Song-lin(许松林),ZHENG Tao(郑弢),XU Shi-min, et al(许世民等).The study of refiningL-lactic acid by molecular distillation(精制L-乳酸的分子蒸馏工艺研究)[J].J ChemEng ofChineseUniv(高校化学工程学报),2004,18(2):246-249.
[2]WU Peng(吴鹏),ZHANG Dong-ming, et al(张东明等).Short-path distillation theory and its application in industry(短程蒸馏原理及工业应用)[J].Progress ofChemicalEngineering(化工进展),2000,1:49-52.
[3]RuckensteinE,HassinkW.The conbined effect of diffusion and evaporation on the molecular distillation of ideal binary liquid mixture[J],SepSciTechnol,1983,18(6):523-545.
[4]KawalaZ,StephanK.Evaporation rate and separation factor of molecular distillation[J],ChemEngTechnol,1989,12:406-413.
[5]KawalaZ.Modeling of short-path high vacuum distillation[A].InstChemSympSer128.Distillation andAdsorption[C],1992,B195-B201.
[6]CvengroJ, et al.Film wiping in the molecular evaporator[J].ChemEngJ,2001,81:9-14.
[7]ChapmanS,CowlingT G.TheMathematicalTheory ofNon-uniformGases,2nd ed.[M].Cambridge,CambridgeUnivPress,1971.
[8]YenS M.Numerical solution of the nonlinear boltzmann equation for non-equilibrium gas flow problem[J].AnnRevFluidMech,1984,16:67-97.
[9]BhatnagarP L,GrossE P,KrookM.A model for collision processes in gases.I [J].PhysRev,1954,94:511-525.
[10]SofoneaV,SekerkaR F.BGK models for diffusion in isothermal binary fluid systems[J].PhysicaA,2001,299:494-520.
[11]FENG Kang(冯康).NumericalComputationalMethods(数值计算方法)[M].Beijing(北京):NationalDefenceIndustryPress(国防工业出版社),1978.
[12]]Tk徼A,CvengroJ.Continuous processes in wiped films.1.Multistage molecular distillation in an arrangement with a single convex-shape evaporator body[J].IndEngChemProcessDesDev,1978,17(3):242-245.
[13]CvengroJ,Tk徼A.Continuous processes in wiped films.2.Distilling capacity and separating efficiency of a molecular evaporator with convex evaporating surface[J].IndEngChemProcessDesDev,1978,17(3):246-251.
[14]PerryE S,WeberW H.Vapor pressures of phlegmatic liquids.Ⅱ[J].J AmChemSoc,1949,71:3726-3730.
[15]YawsC L.ChemicalPropertiesHandbook[M].NewYork,McGraw-Hill,1999.
[16]BriedE M, et al.Synthetic lubricant fluids form branched-chain diesters[J].IndEngChem,1947,39:484-491.
基本信息:
中图分类号:TQ028.31
引用信息:
[1]张旭斌,许春建,周明.降膜分子蒸馏过程模型研究[J],2004(05):558-563.
基金信息:
国家自然科学基金资助项目(20136010)。