膜蒸馏过程传质传热机理研究

A STUDY OF THE MASS AND HEAT TRANSFER PROCESS IN MEMBRANE DISTILLATION

膜蒸馏机理的研究,对于认识该过程的本质及其影响因素,强化优化过程和设计计算有着重要的指导意义。K.Schneider 和R.W.Schofield 等曾对直接接触膜蒸馏的机理进行了研究,A.S.Jonsson 和Shoji Kimura 等对气隙膜蒸馏的机理进行了研究。他们的研究中有很多有价值的认识和结论,但都尚未建立起完善的模型,主要问题有:(1)在已建立的模型中均有大量的经验参数,需要通过膜蒸馏实验才能确定,模型缺乏预测性和通用性;(2)各模型均未考虑热侧水溶液的浓度极化对过程的影响。本文在上述学者工作的基础上,对直接接触膜蒸馏的过程机理进行了深入研究,建立了较为完善的数学模型。

To study the mechanism in membrane distillation is of great significancein understanding the nature of the process,finding the factors that affectthe process,and reinforcing the optimization process and in calculationand design.K.Schneider and R.W.Schofield have studied the mechanismof direct-contact membrane distillation;A.S.Jonsson and Shoji Kimurahave studied the mechanism of air-gap membrane distillation.The main problems in their models are:(1) there are many experimental parameterswhich must be determined from a lot of experiments,so those models aremore theoretical than practical;(2) concentration polarization hasn't beentaken into consideration.Mechanism of direct-contact membrane distillation is then put into deepinvestigation on the basis of former researchers' work.And a much precisemathematical model is set up.