Operation mode of ultrafiltration technology

There are three common operating modes in the ultrafiltration process.

(1) Single-stage intermittent operation: In the ultrafiltration process, in order to reduce the influence of concentration polarization, the membrane module must maintain a high feed-liquid flow rate, but the permeation flux of the membrane is small, so the feed-liquid must be in the membrane module. It is the most basic feature of the industrial filter device that the liquid can be concentrated to the required level through multiple cycles. Intermittent operation is suitable for processing products in laboratories or small-scale intermittent production.

(2) Single-stage continuous operation: Compared with intermittent operation, its characteristic is that the ultrafiltration process is always carried out at a concentration close to the concentrated solution, so the permeation volume and rejection rate are both low. In order to overcome this shortcoming, multi-stage continuous operation can be used .

(3) Multi-stage continuous operation: the concentration of the circulating liquid in each stage increases sequentially, and the last stage leads to the concentrated liquid, so the feed liquid in the previous stages can be operated at a lower concentration. This continuous multi-stage operation is suitable for large-scale industrial production.