Gas Phase Polymer Transfer Separator
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing processes for producing olefin polymers in gas phase are costly and inefficient, particularly in transferring polymers between reactors, leading to high investment and operating costs and suboptimal production of multimodal polymers with varying molecular weights and comonomer contents.
Innovation Solution
A process involving two consecutive gas phase reactors with a separation vessel to transfer olefin polymers, where the first reaction gas mixture is recycled and the polymer is withdrawn and reintroduced into the second reactor, maintaining similar pressure in the separation vessel to the first reactor, allowing for continuous or intermittent transfer and enabling the production of multimodal polymers with differing molecular weights and comonomer contents.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a liquid-filled column or high pressure flash is used to transfer polymer from loop reactor to gas phase reactor, then the carry-over of reactants is eliminated, but the investment cost and operating cost increase significantly
Solution Approach 1:
A gas-phase separator is introduced as an intermediary device between the loop reactor and gas phase reactor. This separator uses gravity and gas flow to separate polymer particles from the reaction gas mixture without requiring liquid filling or high-pressure flashing, thereby eliminating reactant carry-over while avoiding the high costs associated with conventional transfer methods
Solution Approach 2:
The invention changes the phase parameter of the separation medium from liquid to gas. By using a gas-phase separator instead of a liquid-filled column, the process avoids the complexity and cost of liquid handling while effectively separating polymer particles through gravity settling and gas flow control
2Productivity
If conventional transfer methods are used between polymerisation reactors, then polymer transfer is achieved, but the operating cost and complexity increase
Solution Approach 1:
The gas-phase separator acts as a simple intermediary that allows direct transfer of polymer particles between reactors. By using gas flow and gravity separation instead of complex mechanical transfer systems, the invention reduces device complexity while maintaining efficient polymer transfer
Solution Approach 2:
The invention extracts the polymer particles from the reaction gas mixture in the separator, leaving the gas phase behind. This simple extraction process eliminates the need for complex transfer mechanisms while ensuring efficient polymer movement between reactors
3Adaptability or versatility
If single-stage polymerisation is used, then the process is simple, but multimodal polymers with varying molecular weights and comonomer contents cannot be produced
Solution Approach 1:
The polymerisation process is segmented into multiple stages, with each reactor producing polymer with specific properties. The first gas phase reactor produces polymer with one molecular weight distribution and comonomer content, while the second reactor produces polymer with different characteristics. These segmented processes are combined to create multimodal polymers with tailored properties
Solution Approach 2:
The invention merges the outputs of multiple polymerisation reactors through the gas-phase separator system. By combining polymer streams from reactors operating under different conditions, the process produces multimodal polymers with desired molecular weight distributions and comonomer contents while maintaining overall process simplicity
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This process significantly reduces investment and operating costs while enabling the production of multimodal olefin polymers with widely differing molecular weights and comonomer contents, improving the efficiency of polymer transfer between reactors.
Implementation Method 1
directing said first product stream into a separation vessel to form a bed of polymer in said separation vessel
Implementation Method 2
polymerising an olefin in a first polymerization reactor in the presence of an olefin polymerisation catalyst
Data Source
AI summary
The present invention deals with a process of producing a polymer of at least one olefin in two consecutive reactors in gas phase in the presence of an olefin polymerization catalyst where an olefin is polymerized in a first polymerization reactor in the presence of an olefin polymerization catalyst and a first reaction gas mixture to form a fluidized bed comprising an olefin polymer and said first reaction gas mixture.