Flow Control with Tangential Flow Filtration
In tangential flow filtration (TFF), the necessary cross-flow is controlled via the speed of the recirculation pump. The cross-flow is measured by a Sonotec flow meter that is typically located at the outlet of the TFF module (retentate flow). The RS485/Modbus digital signal from the sensor is sent to the FCS (Flow Controller System) to control the volume flow rate.
The required transmembrane pressure (TMP) is set manually in the retentate flow line by means of a control valve (TMP is not directly controlled by the FCS). Overpressure shutoff and PID flow control is regulated through the FCS and can be performed by using an additional pressure sensor located between the pump and the TFF module.