摘要 |
<p>Dry synthetic polymer granules, especially polyester granules, are obtained by drying below the fusion temp the granules passing momentarily into the plastic state in a vertical dryer operating continuously without using a blowing agent. The granules are passed by stages into a cylindrical container and against rebound bodies, which are immobile or vibrating at a low amplitude, in direct prolonged contact with hot air or hot inert gas, with partial crystallisation, to a first drying and a fine drying and crystallisation, including homogenisation. The passage of the granules through the various stages is controlled entirely by a measuring device converted to the exit of the dryer, or by a transforming machine installed after this device.</p> |