采用装配自产双极膜和阳膜的两隔室双极膜电渗析装置,研究了将10％(质量分数)葡萄糖酸钠溶夜转化为葡萄糖酸的实验过程.双极膜电渗析过程可使葡萄糖酸钠溶液电导率降低到3 mS/cm,实现超过95％转化率;随着料液中葡萄糖酸钠浓度的逐渐降低,电流密度、电流效率、产酸量均逐渐下降,而产酸能耗逐渐升高.随着膜对电压的升高,电流密度和产酸量均增加,产酸能耗也增加;膜对电压分别为1.3、1.5和1.8V时对应的电流密度为206、278和340 A/m2,对应的产酸量为56、73和98 mol/(m2·h),对应的产酸直流能耗为48、55和62kW· h/kmol;膜对电压的升高导致了较低的资本支出和较高的运营支出,最佳的膜对电压取决于总支出的最小化;当采用膜对电压为1.5V时第1年的总支出最小,但随后年份中膜对电压1.3V时的总支出最小.%The process of converting 10％ sodium gluconate feed to gluconic acid with a two-chambered bipolar membrane electrodialysis pilot module was studied.It was indicated that the electrical conductivity of sodium gluconate could be reduced to 3 mS/cm and the conversion rate could reach 95％.As the concentration of sodium gluconate decreased,the current density,the current efficiency and the acid generation rate gradually declined,but the energy consumption for per unit of produced acid increased significantly.With the increase of the voltage per cell pair,the current density and the acid generation rate increased,but the energy consumption increased too.When the cell-pair voltage was 1.3,1.5 and 1.8 V,the current density was 206,278 and 340 A/m2 respectively,and the acid generation rate was 56,73 and 98 mol/(m2 · h) respectively,and the energy consumption for per unit of produced acid was 48,55 and 62 kW · h/kmol respectively.The increase of the cell-pair voltage caused the lower capital expenditure and the higher operating expenditure.The optimum cell-pair voltage should be decided by the overall expenditure.With the cell-pair voltage at 1.5 V,the first year overall expenditure was the least.But as the growth of the years,the cell-pair voltage at 1.3 V could cause the minimum overall expenditure.
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