Polymer flake degassing system and methods
AssigneeChevron Phillips Chemical Company LP
InventorsKenneth A. Dooley, Jeffrey S. Lowell, Joseph Curren
Life of this patent
Estimating the term…
Abstract
Systems and methods for improved degassing of polymer flake are provided herein. These systems include a polymerization reactor configured to polymerize one or more olefin monomers and produce a product stream comprising solid polymer flake entrained in a fluid; a flash chamber configured to separate the solid polymer flake from the fluid and to produce a fluid stream and a concentrated stream; and a first degassing chamber configured to separate the concentrated stream by contacting the concentrated stream with a purge fluid comprising one or more light hydrocarbons to produce a partially degassed polymer flake stream and a purge fluid stream.
Claims20
A system for polymerizing one or more olefin monomers, comprising:
- a polymerization reactor configured to polymerize one or more olefin monomers and produce a product stream comprising solid polymer flake entrained in a fluid;
- a flash chamber configured to separate the solid polymer flake from the fluid and to produce a fluid stream and a concentrated stream of solid polymer flake entrained in the fluid, wherein the fluid stream comprises the solid polymer flake in a lower concentration than in the product stream, and wherein the concentrated stream comprises the solid polymer flake in a higher concentration than in the product stream;
- a flash recycle line fluidically coupling the flash chamber to the polymerization reactor, wherein the flash recycle line is configured to recycle the fluid stream from the flash chamber to the polymerization reactor,
- a degassing chamber configured to separate the concentrated stream by contacting the concentrated stream with a purge fluid comprising one or more light hydrocarbons to produce a partially degassed polymer flake stream and a purge fluid stream, wherein the purge fluid has a superficial velocity about 90% or less of a minimum fluidization velocity of the solid polymer flake, wherein the partially degassed polymer flake stream comprises the fluid in a lower concentration than in the concentrated stream and the purge fluid stream comprises the solid polymer flake in a lower concentration than in the concentrated stream;
- and
- a purge recycle line fluidically coupling the degassing chamber to the polymerization reactor, wherein the purge recycle line is configured to recycle the purge fluid stream from the degassing chamber to the polymerization reactor,
- wherein the flash chamber and the degassing chamber are both within a single piece of equipment, and
- wherein the purge recycle line is distinct from the flash recycle line.
A process for polymerizing one or more olefin monomers comprising:
- polymerizing one or more olefin monomers in a polymerization reactor to form a product stream comprising solid polymer flake entrained in a fluid;
- passing the product stream to a flash chamber to produce a fluid stream and a concentrated stream of solid polymer flake entrained in the fluid, wherein the fluid stream comprises the solid polymer flake in a lower concentration than in the product stream and the concentrated stream comprises the solid polymer flake in a higher concentration than in the product stream;
- recycling the fluid stream from the flash chamber to the polymerization reactor;
- passing the concentrated stream to a degassing chamber being in a single piece of equipment as the flash chamber, wherein a purge fluid comprising one or more light hydrocarbons contacts the concentrated stream to produce a partially degassed solid polymer flake stream and a purge fluid stream, wherein the purge fluid has a superficial velocity about 90% or less of a minimum fluidization velocity of the solid polymer flake, wherein the partially degassed polymer flake stream comprises the fluid in a lower concentration than in the concentrated polymer flake stream and the purge fluid stream comprises the solid polymer flake in a lower concentration than in the concentrated stream;
- and
- recycling the purge fluid stream separately from the fluid stream to the polymerization reactor.
Dependencies are inferred from the claim text.