The problem of runaway smelt explosions due to a sudden influx of smelt into a dissolving tank is mitigated by a system comprising an ultrasonic transducer configured to emit ultrasonic waves toward the dissolving tank at a frequency above 20 kilohertz. A system comprising the ultrasonic transducer may further comprise sensors and a data processor configured to regulate the properties of the ultrasonic waves in response to process conditions affecting the smelt flow.