| 摘要 |
The method for treating materials in liquids involves passing them with the liquid through a processing gap formed by a flow passage whose walls are closely spaced and move relative to one another transversely to the direction of flow, thereby producing "supra-kolmogoroff" mixing eddies in the gap, and at the same time applying ultrasonic longitudinal pressure oscillations that reverberate between the two closely spaced surfaces into the gap transversely to the direction of flow from transducers mounted on one wall, thereby producing "sub-Kolmogoroff" mixing eddies therein. The method is capable of rapidly producing relatively thick slurries of sub-micrometer particles that otherwise can take several days in conventional high shear mixers and ball or sand mills, or of rapidly dissolving difficultly soluble gases and powders into liquids. One type of apparatus consists of two circular coaxial plates, one stationary while the other is rotated, the opposed faces forming the processing gap being mirror finished; the rotational axis can be vertical or horizontal. Another type consists of an inner cylinder rotatable about a horizontal axis inside a stationary hollow outer cylinder with the facing walls closely spaced at their lowermost parts to form the processing gap. The ultrasonic transducers are mounted on the stationary member. The liquid/material mixture may be recirculated through a single mill or may be passed through a series of mills. The mixture may be pretreated in a high capacity reverbatory ultrasonic mixer before being fed to the mill or series of mills.
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