Process and apparatus for separating diluent from polymer solids
AssigneeChevron Phillips Chemical Company LP
InventorsThomas A. Reid, Scott E. Kufeld, John H. Tait, David H. Burns, Donald W. Verser
Life of this patent
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Abstract
Polymer solids are maintained in an intermediate pressure zone for a desired polymer solids residence time and then transferred to a purge zone or other lower pressure zone. An increase in the polymer solids residence time in the intermediate pressure zone allows more diluent to flash or separate, thereby avoiding or reducing the need for a low pressure flash zone. A fluff chamber may be disposed between the intermediate pressure zone and a lower pressure zone transporter tank may be used to transport polymer solids after the intermediate pressure zone.
Claims21
A process for slurry polymerization of olefins and for separating polymer solids from diluent, the process comprising:
- polymerizing in a reaction zone at least one olefin monomer in a liquid diluent to produce a fluid slurry comprising the liquid diluent and polymer solids;
- withdrawing a portion of the slurry from the reaction zone;
- heating the withdrawn portion of the slurry;
- passing the withdrawn portion of the slurry to an intermediate pressure zone in which a majority of the diluent is separated from the polymer solids, wherein the intermediate pressure zone is at a pressure in the range of from 100 psia to 1500 psia;
- withdrawing the polymer solids from the intermediate pressure zone;
- and
- transferring the polymer solids to a purge zone without passing through a flash zone.
A process for slurry polymerization of olefins and for separating polymer solids from diluent, the process comprising:
- polymerizing in a reaction zone at least one olefin monomer in a liquid diluent to produce a fluid slurry comprising the liquid diluent and polymer solids;
- withdrawing a portion of the slurry from the reaction zone;
- passing the withdrawn portion of the slurry to an intermediate pressure zone in which a majority of the diluent is separated from the polymer solids, wherein the intermediate pressure zone is at a pressure in the range of 100-1500 psia;
- withdrawing the polymer solids from the intermediate pressure zone;
- monitoring the level of the polymer solids in the intermediate pressure zone;
- and
- adjusting the withdrawal of the polymer solids from the intermediate pressure zone in response to the monitored level.
A process for slurry polymerization of olefins and for separating polymer solids from diluent, the process comprising:
- polymerizing in a reaction zone at least one olefin monomer in a liquid diluent to produce a fluid slurry comprising the liquid diluent and polymer solids;
- withdrawing a portion of the slurry from the reaction zone;
- introducing the withdrawn portion of the fluid slurry to an intermediate pressure zone in which a majority of the diluent is separated from the polymer solids, wherein the intermediate pressure zone is at a pressure in the range of 100-1500 psia;
- holding the polymer solids in the intermediate pressure zone for a polymer solids residence time sufficient to remove substantially all the unentrained diluent;
- and
- withdrawing the polymer solids from the intermediate pressure zone;
- and
- transferring the polymer solids to a purge zone to remove substantially all the entrained diluent.
Dependencies are inferred from the claim text.