GB834403A - Improvements in or relating to the treatment of materials with liquids - Google Patents

Abstract

<PICT:0834403/IV(c)/1> <PICT:0834403/IV(c)/2> Hides, fabrics, fibrous materials and the like immersed in a liquid are treated with ultrasonic irradiation by producing cavitation conditions in the liquid by paddles moving at high speed (preferably 100-250 m.p.h.) relative to the material at a small separation (preferably 0.5 inch) from it, in order to produce cavitation bubbles which collapse in contact with the material. In Fig. 1 hides 14 are held to the drum 11 by wire mesh grids 15 and a surrounding drum 12 carrying paddles 28 is rotated in relation to drum 11 in liquid in a vessel, not shown. Fig. 2 provides for the treatment of material 16 which is wound from supply reel 17 to take-up reel 18 through guide-rollers 19, 21 separated by a fairing 22. The paddles 30 are set at an angle to divert the cavitation pockets towards the material, which action may be assisted by a liquid flow through the material. If the material to be treated is fibrous it may be held (Fig. 3, not shown), between retaining meshed belts and passed linearly through an elongated tank while the adjacent paddles are carried by two endless belts. The paddles may be of quadrilateral cross-section set at rightangles to the direction of motion, as shown at 28 in Fig. 1, or inclined as shown at 30 in Fig. 2. More elaborate constructions are shown in Fig. 4 (not shown), designed to allow liquid to flow between the paddles to impart a strong transverse vibration thereto when the apparatus is operating.