摘要
为明晰利用双极膜将盐转化为酸碱过程的传质规律并以此指导工业生产,以Na_(2)SO_(4)为原料,依据Nernst-Planck方程、泊松方程构建双极膜单元模型,采用COMSOLMultiphysics软件计算确定网格数、膜基团容量等关键参数,模拟计算了不同膜单元电压、进料浓度条件下盐的转化率,并与实验数据进行对比。结果表明:双极膜单元网格数为30000、阴/阳膜离子膜基团容量为300mol/m^(3)时,获得的传质模型模拟结果与实测数据吻合度较高;在此基础上,计算获得了双极膜单元中电势分布、离子分布、离子迁移通量分布等传质过程数据,发现利用双极膜将Na_(2)SO_(4)转化为相应酸碱的传质效率及能效主要与跨膜压降、膜单元电压有关。
In order to clarify the mass transfer law in the process of salt conversion into corresponding acid and base by introducing bipolar membrane and thus to instruct industrial production with it,a model of electrodialysis unit cell with Na_(2) SO_(4) as the raw material was constructed by introducing bipolar membrane(BPM)based on Nernst-Planck and Poisson equations.Key parameters including the number of grids and the capacity of membrane groups of the unit cell were obtained by calculating with COMSOL Multiphysics software.The salt conversion rates in the unit cell with different voltage and feed concentration were calculated based on simulation,and then compared with the experimental data.The results show that with the grid number of 30000 and the membrane group capacity of negative/positive membrane at 300 mol/m^(3),the simulated results with the constructed model are in good agreement with the measured data.Based on the corresponding calculation,data of potential distribution,ion distribution and distribution of ion migration flux in the unit cell during mass transfer process were obtained.It is found that the mass transfer rate and energy efficiency of Na_(2) SO_(4) converted into corresponding acid and base by bipolar membrane are mainly influenced by voltage drop and membrane voltage in the unit cell.
作者
曾娟
张玉凤
刘孟
余侃萍
ZENG Juan;ZHANG Yufeng;LIU Meng;YU Kanping(Changsha Research Institute of Mining and Metallurgy Co.,Ltd.,Changsha 410012,Hunan,China)
出处
《矿冶工程》
北大核心
2025年第1期123-128,132,共7页
Mining and Metallurgical Engineering
基金
深地国家科技重大专项(2024ZD1004006)。
关键词
双极膜
传质
模型
数值模拟
离子交换膜
电渗析
膜分离
酸碱回收
bipolar membrane
mass transfer
model
numerical simulation
ion exchange membrane
electrodialysis
membrane separation
acid and base recovery
