Abstract: The method is for treating a liquid or slurry with an ultrasonic energy. A first rotatable member being permeable to a medium and a first vibrating device are provided. The first vibrating device and the first member have a first gap formed therebetween so that the first gap represents a first distance. A guide member aligned with the first member exerts a pressure on the medium. The guide member breaks up fiber flocculation close to the upper surface of the medium. The medium is fed between the first member and the guide member. The first vibrating device generates pulses through the first member to form imploding bubbles in the medium. The bubbles have a critical diameter prior to implosion that is greater than the first distance to prevent the bubbles from growing in the first gap to a size greater than the first distance.

Abstract: The method is for treating a liquid or slurry with an ultrasonic energy. A movable endless member is provided that is permeable to a liquid. A transverse foil is disposed below the member and extends across the member and a transducer is in operative engagement with the foil. The member is moved about rollers. The transducer generates pressure pulses into the foil to form implosion bubbles in the liquid disposed above the member. The implosion bubbles have a first diameter (d1). A gap is formed between the member and the foil. The gap represents a distance (d2) that is less than the diameter (d1) of the bubbles to prevent any bubbles of critical size to be captured in the gap.

Abstract: The method is for treating a liquid or a slurry of a liquid and solids, such as sludge, soil or fiber webs, with an ultrasonic energy. Movable endless members (214, 230) are provided that are permeable to the liquid portion of a slurry (204). An ultrasonic transducer (236) is disposed adjacent to the member (214) and the ultrasonic transducer (234) is disposed adjacent to the member (230). The slurry is fed in between the members (214, 230). The transducers (234, 236) generate pressure pulses through the members (230, 214) to form imploding bubbles (227) in the slurry. The bubbles (227) have a diameter (d5) that is greater than a distance (d3) between the transducer (234) and the member (230) and a distance (d4) between the transducer (236) and the member (214) to prevent the bubbles (227) from being captured between the transducers (234, 236) and the members (230, 214).

Abstract: The method is for applying a coating on a paper substance. A paper moves over a set of rollers. A coating is applied with a coating applicator that has ultrasonic transducers to vibrate the coating to reduce the viscosity of the coating. A downstream blade has an ultrasonic transducer in operative engagement with the blade. The vibrating blade is applied to the paper for scraping off excessive coating from the paper.