Combined ultrasonic air backwash process to clean immersed membranes involves applying ultrasound to liquid during backwash and blowing gas over outer membrane surface

摘要

The air backwash process is used in a filter unit to clean at least one immersed membrane in a module (2) on a filtration tank (3) containing a liquid mixture (4) by application of ultrasound from sound producers (1) to the membranes. Ultrasound is applied to the liquid during backwash, and gas is blown over the outer membrane surface.