Polyether Polyol Water Removal via Controlled Distillation Pressure
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing processes for removing water from polyether polyols during batch distillation often result in foam overflow, leading to wastewater contamination and reduced productivity, especially when dealing with higher molecular weight polyols, as the reaction of water with alkaline catalysts is undesirable and can cause foaming issues during distillation.
Innovation Solution
A controlled batch distillation process where the polyether polyol is heated within specific temperature ranges while maintaining pressures above normal atmospheric pressure, with controlled pressure increase and decrease rates to manage the removal of water, reducing foam formation and allowing for larger batch sizes by minimizing foam overflow.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If batch distillation is used to remove water from polyether polyol, then water removal efficiency is improved, but foam overflow occurs leading to productivity reduction
Solution Approach 1:
The patent applies parameter changes by precisely controlling pressure and temperature parameters during batch distillation. The pressure is controlled to increase at a rate of 0.01 to 1 psi/sec and decrease at 0.001 to 0.1 psi/sec, while temperature is maintained within specific ranges (100-140°C for atmospheric distillation, 110-150°C for vacuum distillation). These parameter optimizations enable effective water removal while preventing foam overflow, thus resolving the contradiction between water removal efficiency and productivity.
2Productivity
If batch size is increased to utilize more reactor capacity, then productivity is improved, but foam overflow frequency increases
Solution Approach 1:
The patent applies dynamics by implementing dynamic control of pressure during the distillation process. The pressure is not held constant but is actively adjusted at controlled rates (increase: 0.01 to 1 psi/sec, decrease: 0.001 to 0.1 psi/sec) based on process conditions. This dynamic pressure control adapts to the foaming behavior during distillation, enabling larger batch sizes to be processed without foam overflow, thus resolving the contradiction between productivity and foam overflow frequency.
3Device complexity
If pressure is maintained at atmospheric pressure during distillation, then equipment complexity is reduced, but foam formation increases
Solution Approach 1:
The patent applies periodic action by alternating between atmospheric pressure distillation and vacuum pressure distillation in a controlled sequence. The process first conducts atmospheric distillation with controlled pressure increase, then transitions to vacuum distillation with controlled pressure decrease. This periodic pressure variation effectively manages foam formation at different stages, resolving the contradiction between equipment complexity and foam formation without requiring complex continuous vacuum equipment.
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 effectively reduces the frequency of foam overflow, enabling increased reactor capacity utilization by maintaining controlled pressure and temperature conditions during distillation, resulting in a more efficient and productive water removal process from polyether polyols.
Implementation Method 1
heating the polyether polyol to a temperature within a first predetermined distillation temperature range... to remove a first portion of the water from the polyether polyol
Implementation Method 2
heating the polyether polyol to a temperature within a first predetermined distillation temperature range... to remove a first portion of the water
Implementation Method 3
controlling the rate of increase in vessel pressure within a predetermined pressure increase rate range... and controlling the rate of decrease in vessel pressure within a predetermined pressure decrease rate range
Data Source
Figure 1
Figure 2A
Figure 2B
AI summary
Disclosed are processes and systems for removing water from a polyether polyol that employs a controlled temperature and pressure profile.