Abstract

Methods and circuits for a device for interrupting the concentration-related polarisation phenomenon and for the self-cleaning of electromembrane processes by application of asymmetric inverse-polarity pulses with high intensity and variable frequency are described. The device, a bipolar switch, is based on the use of solid-state electronic elements such as MOSFET (Metal- Oxide-Semiconductor Field-Effect Transistor) or IGBT (Insulated Gate Bipolar Transistor) to carry out polarity inversion in a range of frequencies, intensities and pulse widths in order to prevent or reduce the formation of precipitates on the surfaces of the membranes. The inversion protocol, with a frequency that varies as a function of the appearance of dirt on the membranes, as measured by the decrease in voltage or electrical resistance of the membrane cell during electromembrane processes, is also provided. High frequencies can be applied, either alone or together with other physicochemical in situ cleaning procedures (CIP, cleaning in place), when cleaning of the system is required. Various solid-state electronic elements can be connected in parallel. Said plurality of elements allows the application of higher powers. This device and configuration provides the application of modulated and stable high-intensity pulses using a second power source. Electromembrane processes can be easily updated by replacing the electrodes, suitable for polarity inversion, and adding a second power source and the bipolar switch described.