Verfahren und Vorrichtung zum Vorwaschen verschmutzter, vorzerkleinerter thermoplastischer Kunststoff-Folien

摘要

Contaminated and disintegrated thermoplastic films are washed in a liquid which is passed through a hydrocyclone and a frictional separator to secondary disintegration and further treatment. The liquid concerned is pumped up to a deodetic height of 1.0-10.0 m or more above the hydrocyclone; the films in strips 50-700 mm (pref. 500 mm) wide and 0.5-6.0 m (pref. 3.0 m) long are fed at this height into the liq. in a ratio of greater than 1:5 strips:liquid; the mix then falls freely to a nozzle-shaped overflow on the hydrocyclone. The layout feeds the strips of film in (17) to a pipe-line (18) at height (H) above a hydrocyclone (1) which has a top overflow (2) and bottom outlet (4) fitted with double-sliding plate below (5). The strips are passed by an overflow (2) through a pipe (7) to a frictional separator (8) where liquid adhering to them is removed. The dewatered strips pass to a sec. disintegrator (10) and from there to the user equipment. The liquid removed flows (12) to a filter (13) and dirt is separated (14). The filtered liquid is finally pumped (15) and recirculated. Energy is saved by diverting some of the liquid (22) back to the hydrocyclone directly (19). ADVANTAGE - The procedure is a simple way of reliably washing film in strips in a turbulent liq. (without the existing problem of agglomerating into lumps).