Stirrer Power Control for (Meth)acrylonitrile Polymerization
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In solution polymerization for preparing (meth)acrylonitrile-based polymers used in carbon fibers, high viscosity reaction solutions lead to increased power consumption and variations in polymer physical properties due to inefficient mixing, resulting in higher production costs and reduced polymerization conversion ratios.
Innovation Solution
Performing solution polymerization under specific power consumption conditions based on the viscosity of the reaction solution, with 1-5 kW/m3 for viscosities of 0.1-250 poise and 8-13 kW/m3 for viscosities of 250-450 poise, using a (meth)acrylonitrile-based monomer and reaction solvent in a reactor equipped with a suitable stirrer, to ensure efficient mixing and controlled heat management.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If the stirrer constantly consumes power to mix the reaction solution, then the mixing is maintained, but the power consumption increases unnecessarily when the viscosity is low
Solution Approach 1:
The patent applies dynamic control of the stirrer by adjusting its rotation speed according to the reaction solution's viscosity changes during polymerization. The stirrer operates at different speeds in different stages: higher speed when viscosity is low to ensure mixing, and lower speed when viscosity increases to reduce energy consumption while maintaining adequate mixing. This dynamic adjustment resolves the contradiction between maintaining mixing quality and reducing unnecessary energy consumption.
2Ease of operation
If the stirrer operates at high power to handle high viscosity, then mixing is maintained, but production costs increase due to unnecessary energy consumption
Solution Approach 1:
The patent implements dynamic power adjustment of the stirrer based on real-time viscosity monitoring. During early polymerization stages when viscosity is low, the stirrer operates at lower power to avoid unnecessary energy consumption. When viscosity increases to higher levels, the power is increased only to the extent needed to maintain adequate mixing. This staged power adjustment directly reduces production costs while maintaining mixing quality throughout the process.
3Productivity
If the reaction solution viscosity increases during polymerization, then polymerization conversion ratio increases, but mixing becomes inefficient causing variations in polymer physical properties
Solution Approach 1:
The patent employs dynamic stirrer speed adjustment that responds to viscosity changes during polymerization. As the reaction progresses and viscosity increases, the stirrer speed is increased to compensate for the thicker solution, maintaining adequate mixing efficiency. This dynamic response allows the system to achieve high polymerization conversion ratios while preventing the mixing inefficiency that would otherwise occur at high viscosity levels, thereby avoiding variations in polymer physical properties.
Solution Approach 2:
The patent implements a feedback control mechanism where the stirrer operation is continuously adjusted based on the reaction solution's viscosity state. The system monitors viscosity changes during polymerization and provides feedback to adjust stirrer speed accordingly. This feedback loop ensures that mixing efficiency is maintained throughout the polymerization process even as viscosity increases, allowing high conversion ratios to be achieved without compromising product uniformity.
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 method reduces energy consumption, maintains consistent physical properties of the polymer, and increases the final polymerization conversion ratio, enhancing the production efficiency and quality of (meth)acrylonitrile-based polymers for carbon fibers.
Implementation Method 1
Solution polymerization is performed by smoothly mixing a reaction solution in a reactor using a stirrer
Implementation Method 2
adding a reaction solution comprising a (meth)acrylonitrile-based monomer and a reaction solvent to a reactor to perform solution polymerization
Data Source
AI summary
The present invention relates to a method of preparing a (meth)acrylonitrile-based polymer for preparing a carbon fiber, which comprises adding a reaction solution comprising a (meth)acrylonitrile-based monomer and a reaction solvent to a reactor to perform solution polymerization, performing solution polymerization under a condition in which a power consumption of the reactor is 1 to 5 kW/m3 when the reaction solution in the reactor has a viscosity of 0.1 poise or more and 250 poise or less, and performing solution polymerization under a condition in which a power consumption of the reactor is 8 to 13 kW/m3 when the reaction solution in the reactor has a viscosity of more than 250 poise and 450 poise or less.