Separating oversize polymer chips after wet pelletizing involves running chips suspended in water over a perforated inclined plate

摘要

Polymer chips produced by any of the pelletizing methods involving water cooling are mixed with water in a vessel (18) and circulated by a pump (19) over a perforated inclined plate (3). Oversize or misshapen chips are sieved out and removed periodically from a chamber (7). The remainder is pumped to a cyclone separator (16) where the chips are removed and the water is recirculated. The perforated plate (3) is inclined at an angle of 15 to 80 deg to the vertical, with a length to width ratio between 0.3 and 50 to 1. The perforations are transversely elongated holes with a length 1.5 to 50, and a width 1.5 to 20 times the chip size respectively.