为克服超滤过程中的浓差极化,防止膜污染,同时提高超滤生产的自动化水平,设计了超声场和脉冲电场复合强化的全自动超滤系统.该系统包括粗滤回路、一级和二级超滤回路、清洗回路和热交换回路,可同时或分别进行多级或单级过滤/超滤,具有较好的操作灵活性.采用分布式分级控制的方式,以工业控制计算机、Simens S7-200 PLC作为控制系统的硬件,基于昆仑MGCS组态环境,实现了超滤过程的自动控制.在南瓜多糖超滤浓缩中的应用表明,所设计的系统可显著提高分离效率和效果,在文中实验条件下,平均膜通量增加了1.15~2.53倍,截留率增幅达15个百分点.

Proposed in this paper is an automatic ultrafiltration system enhanced with ultrasonic and pulse electric field,which is used to overcome the concentration polarization and membrane fouling during the ultrafiltration and improve the automation level of ultrafiltration process.The system consists of a crude filtration loop,two ultrafiltration loops,a cleaning loop and a heat-exchange loop,and possesses excellent operation flexibility because it can simultaneously perform multi-stage or separately perform single-stage ultrafiltration.It also possesses a multi-layer distributed automatic control subsystem based on Kunlun MGCS configuration,which adopts an industrial personal computer and a Simens S7-200 PLC as the system hardware.The application of the proposed system to the concentration of pumpkin polysaccharides shows that,in the adopted experimental conditions,the average permeation flux increases by 1.15~2.53 times and the rejection by 15 points of percentage,which means that the system greatly improves the ultrafiltration efficiency and effect.