Uzdenova Aminat, Urtenov Makhamet
Department of Computer Science and Computational Mathematics, Umar Aliev Karachai-Cherkess State University, 369202 Karachaevsk, Russia.
Department of Applied Mathematics, Kuban State University, 350040 Krasnodar, Russia.
Membranes (Basel). 2021 Nov 13;11(11):873. doi: 10.3390/membranes11110873.
One of the ways to increase the efficiency of the desalination process in membrane systems is to use intensive current modes. Recently, the phenomenon of space-charge breakdown was theoretically described for desalination under intensive current modes. The space-charge breakdown is a decrease in the magnitude and size of the extended space charge regions (SCRs) of opposite signs, formed at the cation- and anion-exchange membranes in the desalination channel, when they approach each other. Therefore, this phenomenon negatively affects the intensity of electroconvection and the efficiency of mass transfer in membrane systems. We report the results of the first theoretical analysis of the space-charge breakdown in the galvanostatic electric mode, which is generally used in the research and operation of membrane systems. For this purpose, a one-dimensional model of the ion transfer of the electrolyte solution in the section of the desalination channel at the direct current is developed. The regularities of changes in the extended SCRs in the galvanostatic mode are determined. A relation is obtained for the onset time of the space-charge breakdown, which makes it possible to determine the parameters of the effective operation of the membrane system.
提高膜系统中脱盐过程效率的方法之一是采用强电流模式。最近，从理论上描述了强电流模式下脱盐过程中的空间电荷击穿现象。空间电荷击穿是指在脱盐通道中阳离子交换膜和阴离子交换膜上形成的、带相反电荷的扩展空间电荷区（SCRs）在相互靠近时，其大小和范围减小的现象。因此，这种现象会对膜系统中的电对流强度和传质效率产生负面影响。我们报告了在恒电流模式下对空间电荷击穿进行首次理论分析的结果，恒电流模式通常用于膜系统的研究和运行中。为此，建立了直流条件下脱盐通道截面处电解质溶液离子转移的一维模型。确定了恒电流模式下扩展SCRs的变化规律。得到了空间电荷击穿起始时间的关系式，这使得确定膜系统有效运行的参数成为可能。
