EDI产水水质影响因素的试验及分析

Experiments and analysis on factors influencing product quality of EDI

研究了淡、浓水流量对膜堆电流、电压的影响,并重点研究了当膜堆电流一定时,淡、浓水流量对EDI产水水质的影响。结果表明:淡水流量的变化对膜堆电流的影响很小;增加浓水流量会减小膜堆电流。当膜堆电流一定时,淡、浓水流量对产水水质的影响主要取决于进出口的淡、浓水压差。当进出口的淡、浓水压差足够时,EDI的产水水质能够得到保证;反之,产水水质则会发生恶化,其中以出口处的淡、浓水压差对产水水质的影响更为突出。试验还发现,当膜堆电流一定时,淡水流量过低会导致产水水质下降;浓水流量的增加则有利于产水水质的提高。

The effects of the flux of dilute water and concentrated water on applied current and applied voltage were studied, and the emphasis was to study the influence of flux of dilute water and concentrated water on the product quality of EDI under the definite applied current. The results showed that： the effect of the flux of dilute water on applied current was tiny and increasing the flux of concentrated water could reduce applied current. When the current was unchanged, the influence of the flux of dilute water and concentrated water on the product quality was mainly decided by the differential pressure between dilute water and concentrated water in the entrance as well as in the exit of EDI. The product quality could be ensured when the differential pressure was enough, contrarily, the product quality would deteriorate, besides, the influence of the differential pressure in the exit on product quality was more prominent. The experiment also found that, too low flux of dilute water result in the decrease of product quality while the augment of the flux of concentrated water would improve the product quality when the applied current was unchanged.