Alkoxylation Reactor Mixing and Temperature Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing processes for continuous alkoxylation of liquid alkylene oxide with organic compounds using tubular and annular-gap reactors face challenges such as high temperature peaks, formation of undesired by-products, high pressures, and limitations in alkylene oxide grades due to inefficient mixing and temperature control.
Innovation Solution
The process involves modifying reactors with intensive mixing using ring slit nozzles, static mixer elements, and multiple tempering jackets to control reaction temperature, allowing for a shorter reactor length and reduced residence time, which improves mixing efficiency and reduces side product formation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If a long reaction tube (200m) is used for continuous alkoxylation, then the reaction can be completed, but the reactor length becomes excessively long and requires high pressures (>100 bar) to prevent vaporization
Solution Approach 1:
The reaction tube is divided into multiple sections (first section, second section, third section) with different functions. The first section performs initial reaction, the second section performs further reaction, and the third section serves as a post-reaction zone with larger cross-section for final product formation. This segmentation allows the reaction to be completed in a much shorter total length without requiring excessive pressure.
2Reliability
If alkylene oxide is fed at multiple locations along the reaction tube, then reaction control is improved, but the device complexity increases due to multiple mass flow controllers and feeding systems
Solution Approach 1:
Multiple alkylene oxide feeding functions are combined into a single feeding system located at the inlet of the reaction tube. The fed alkylene oxide is distributed to different reaction zones through the reaction flow itself, eliminating the need for multiple separate mass flow controllers and complex feeding mechanisms while maintaining effective reaction control.
3Ease of manufacture
If the reaction tube has uniform cross-section, then the reactor design is simple, but the post-reaction zone is insufficient leading to side product formation
Solution Approach 1:
The reaction tube has different cross-sectional areas in different sections. The first and second sections have a first cross-sectional area optimized for reaction, while the third section (post-reaction zone) has a larger second cross-sectional area to provide sufficient residence time and volume for completing the reaction and preventing side product formation. This local variation in geometry optimizes both reaction efficiency and product quality.
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 approach enables the use of shorter reactors, minimizing side products and improving the quality of the end product by maintaining efficient control over reaction conditions, thus avoiding high pressures and by-product formation.
Implementation Method 1
continuously reacting liquid alkylene oxide with a liquid substance comprising an organic compound with one or more active hydrogen atoms and a catalyst
Implementation Method 2
modifying reactors with intensive mixing using ring slit nozzles, static mixer elements, and multiple tempering jackets to control reaction temperature
Data Source
AI summary
Disclosed is a process for continuously reacting liquid alkylene oxide with a liquid substance including an organic compound with active hydrogen atoms and a catalyst in a reactor.