Abstract:
A process for component separation in a polymer production system, comprising separating a polymerization product stream into a gas stream and a polymer stream, wherein the gas stream comprises ethane and unreacted ethylene, distilling the gas stream into a light hydrocarbon stream, wherein the light hydrocarbon stream comprises ethane and unreacted ethylene, contacting the light hydrocarbon stream with an absorption solvent system, wherein at least a portion of the unreacted ethylene from the light hydrocarbon stream is absorbed by the absorption solvent system, and recovering a waste gas stream from the absorption solvent system, wherein the waste gas stream comprises ethane, hydrogen, or combinations thereof.
Abstract:
We disclose a monovinylarene/conjugated diene block copolymer, comprising: (i) a random (conjugated dieneX/monovinylareney)m block, wherein x is about 2.5 wt% to about 10 wt%, y is from about 90 wt% to about 97.5 wt%, and x + y is about 97.5 wt% to 100 wt%; and (ii) a (conjugated dime)n block; wherein n is from about 20 wt% to about 30 wt%, m is from about 70 wt% to about 80 wt%, and m + n is from about 90 wt% to 100 wt%. We also disclose a method of forming the block copolymer and a method for fabricating an article from the block copolymer. The block copolymer typically exhibits a Tg at least about 10°C less than the Tg of a reference polymer differing only in that x is about 0 wt% and y is about 100 wt%.
Abstract:
A process for recovery of ethylene from a polymerization product stream of a polyethylene production system, comprising separating a light gas stream from the polymerization product stream, wherein the light gas stream comprises ethane and unreacted ethylene, contacting the light gas stream with an absorption solvent system, wherein the contacting the light gas stream with the absorption solvent system occurs at a temperature in a range of from about 40° F to about 110° F, wherein at least a portion of the unreacted ethylene from the light gas stream is absorbed by the absorption solvent system, and recovering unreacted ethylene from the absorption solvent system to yield recovered ethylene.
Abstract:
Techniques and systems for producing a polyolefin using reactors in series are described. Described embodiments include techniques and systems for polymerizing a monomer in a first polymerization reactor to form a first polyolefin, discharging a first slurry continuously from the first polymerization reactor to a second polymerization reactor, and discharging a second slurry continuously from the second polymerization reactor. Using continuous take-off devices disposed on either or both reactors, pressure control may be attained such that the rate of transfer between and withdrawal from both reactors are within a desired range.
Abstract:
Embodiments of the present application provide a method for manufacturing a polyolefin and a system for implementing the method. The method comprises combining a catalyst with a diluent mixture containing a diluent and an olefin monomer in a polymerization reactor. The diluent may comprise propane, butane, or isobutane, or a combination thereof. The polymerization reactor is operated at a pressure above a critical pressure of the diluent, but below the critical temperature of the diluent.
Abstract:
The present embodiments provide a system and method for separation within a polymer production process. Specifically, a flashline heater configured according to present embodiments may provide more time than is required for complete vaporization of liquid hydrocarbons that are not entrained within a polymer fluff produced within a polymerization reactor. Such extra time may allow for liquid hydrocarbons that are entrained within the polymer fluff to be vaporized.
Abstract:
A flash chamber sized to receive the effluent discharged from a polyolefin reactor during normal operation of the reactor and during a reactor dump, advantageously eliminating a reactor dump tank or alternate flash tank from the equipment outlay of a polyolefin manufacturing process. The flash chamber is sized to hold at least the polyolefin solids discharged from the reactor. A condenser fluidically coupled to an overhead portion of the flash chamber is sized to condense the flow rate of vaporized hydrocarbon (e.g., diluent, monomer, etc.) discharged overhead from the flash chamber during normal operation and during the reactor dump.
Abstract:
A polymerization loop reactor including a loop reaction zone, a continuous takeoff, and a fluid slurry disposed in the reaction zone. A generally cylindrical wall defines the loop reaction zone. The length of the loop reaction zone and the nominal outside diameter of the generally cylindrical wall define a length / diameter ratio greater than 250. The reactor can be charged with a fluid slurry including an olefin monomer reactant, solid olefin polymer particles, and a liquid diluent. The concentration of the solid olefin polymer particles in the slurry can be greater than 40 weight percent based on the weight of polymer particles and the weight of liquid diluent. Also disclosed is a polymerization process carried out by polymerizing, in the loop reaction zone of a reactor as defined above, at least one olefin monomer in a liquid diluent to produce a fluid slurry as defined above.
Abstract:
Processes and systems for the production for pressure management of a polymerization product flowing from a loop polymerization reactor to a separation vessel in a slurry polymerization system are disclosed herein. For example, a process comprises withdrawing the polymerization product from a loop polymerization reactor, and conveying the withdrawn polymerization product to a separation vessel via a first pressure differential and a second pressure differential. The withdrawn polymerization product may flow through the first pressure differential before flowing through the second pressure differential, and the first pressure differential may be less than the second pressure differential.
Abstract:
A reactor system including an enclosed pressure relief system and/or a control system. The enclosed pressure relief system including a slurry separation system communicatively coupled with a pressure relief valve coupled to a loop reactor such that activation of the pressure relief valve results in discharge of a slurry from the loop reactor to the slurry separation system, wherein the slurry separation system is capable of separating solid and liquid components from gas components of the slurry and transmitting the gas components to a flare via a flare header.