Method and apparatus for making crystalline polymeric pellets and granules
US9032641B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 24, 2013 |
| Grant date | May 19, 2015 |
| Priority date | — |
| Expiry date | May 11, 2033 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF26B17/105
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A method and apparatus for underwater pelletizing and subsequent drying of crystallizing polymers to crystallize the polymer pellets with out subsequent heating is shown in FIG. 5. High velocity air or other inert gas is injected into the water and pellet slurry line (120) toward the dryer near the pelletizer exit (102) at a flow rate from about 100 to about 175 m3/hour, or more. Such high-speed air movement forms a vapor mist with the water and significantly increases th speed of the pellets into and out of the dryer such that the polymer pellets leave the dryer with sufficient latent heat to cause self-crystallization within the pellets. A valve mechanism in the slurry line (150) after the gas injection further regulates the pellet residence time and a vibrating conveyor after the dryer helps the pellets to achieve the desired level of crystallinity and to avoid agglomeration.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.