Patent · US Expired

Process for purifying recirculating gases of condensed polymer particles

US4191821A · kind A · utility

5Cited by
7References
8Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJul 11, 1978
Grant dateMar 4, 1980
Priority date
Expiry dateJul 11, 1998

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC08F210/02
  • WIPO fieldMacromolecular chemistry, polymers
  • WIPO sectorChemistry

Abstract

A process for eliminating low molecular-weight polymers from the recirculating gases of facilities carrying out ethylene polymerization or copolymerization at a pressure of 300 to 2500 bars and a temperature of 130.degree. C. to 350.degree. C., in which facilities the mixture of monomer and polymer leaving the reactor is expanded into a separator operating under a pressure of 50 to 500 bars. The gases are passed, at a temperature at least 20.degree. C. higher than the melting point of the low molecular-weight polymers, through at least one standard cyclone at an inlet velocity between 1 and 10 m/s. The gases are then cooled to a temperature lower than the melting point of the low molecular-weight polymers, and are then passed through at least one heated cyclone at an inlet velocity between 2 and 20 m/s.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.