Advanced wastewater treatment system and method based on ultrasonic wave enhancement and multi-level forward osmosis membrane separation

The invention provides an advanced wastewater treatment system and method based on ultrasonic wave enhancement and multi-level forward osmosis membrane separation. The system comprises an ultrasonic wave enhancement system, a multi-level forward osmosis membrane separation system and a driving liquid circulation and concentration system, wherein the ultrasonic wave enhancement system comprises a generation device and an enhancement device; forward osmosis membranes in the multi-level forward osmosis membrane separation system are semipermeable membranes with an interception function; a core of the driving liquid circulation and concentration system is a multi-effect evaporator system, and a driving liquid is sodium chloride with high concentration or another neutral inorganic salt solution easy to distill with the high concentration. With the adoption of the operating mode integrating the ultrasonic wave enhancement and the multi-level forward osmosis membrane assembly separation, treated effluent of domestic