Lactide Vapor Removal Using Lactic Acid Condensation Absorption
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for removing lactide from gas streams are inefficient, energy-intensive, and prone to equipment blockage due to lactide deposition, particularly at low pressures and temperatures, with varying feed compositions complicating process control.
Innovation Solution
A process involving a condensation-reaction step where a vapor stream containing lactide and water is contacted with a lactic acid reaction liquid, allowing at least 80% lactide absorption while limiting water absorption to 40%, with a residence time of at least 2 hours, followed by a steam effluent condensation to produce a highly concentrated liquid effluent.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional methods are used to remove lactide from gas streams, then lactide removal efficiency is improved, but energy consumption increases and equipment blockage occurs
Solution Approach 1:
The patent changes the chemical parameters of the absorption liquid by using lactic acid instead of conventional solvents, and controls the residence time parameter at least 2 hours to optimize the absorption reaction, achieving high lactide removal efficiency without excessive energy consumption
Solution Approach 2:
The patent introduces lactic acid as an intermediary substance that facilitates the removal of lactide from gas streams through chemical absorption, avoiding the need for high-energy conventional separation methods while preventing equipment blockage
2Quantity of substance
If conventional absorption methods are used, then lactide absorption capacity is improved, but water absorption increases and selectivity decreases
Solution Approach 1:
The patent optimizes the chemical composition parameters of the absorption liquid (lactic acid concentration, purity) and operational parameters (residence time, temperature, pressure) to achieve high lactide absorption capacity while maintaining selectivity and limiting water absorption to no more than 40% of total absorption
3Device complexity
If simple equipment is used for lactide removal, then device complexity is reduced, but operational reliability decreases due to inability to handle varying feed compositions
Solution Approach 1:
The patent uses parameter changes (residence time ≥2 hours, temperature and pressure optimization) to enable a simple absorption device to handle varying feed compositions reliably, achieving high operational reliability without complex 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
The process effectively handles varying feed compositions, prevents lactide precipitation, and reduces energy consumption, ensuring high operational reliability and flexibility without complex equipment.
Implementation Method 1
subjecting a vapour stream comprising lactide and water to a condensation-reaction step in a condensation-reaction apparatus, wherein the vapour stream comprising lactide and water is contacted with a reaction liquid comprising lactic acid
Implementation Method 2
at least 80% of the lactide present in the vapour stream provided to the condensation-reaction step is absorbed in the reaction liquid
Data Source
AI summary
The invention pertains to a process for removing lactide from a vapour stream comprising lactide and water, comprising the steps of ⋅subjecting a vapour stream comprising lactide and water to a condensation-reaction step in a condensation-reaction apparatus, wherein the vapour stream comprising lactide and water is contacted with a reaction liquid comprising lactic acid, the condensation reaction step being carried out under such conditions that at least 80% of the lactide present in the vapour stream provided to the condensation-reaction step is absorbed in the reaction liquid and at most 40% of the water present in the vapour stream provided to the condensation-reaction step is absorbed in the reaction liquid, wherein the residence time in the condensation step is at least 2 hours, the residence time being defined as the total mass of reaction liquid divided by the mass of the product condensing from the vapor stream containing lactide and water per hour, ⋅withdrawing a liquid effluent from the condensation-reaction step, which liquid effluent comprises less than 15 wt. % lactide and less than 30 wt. % of water, the effluent having a total acid content of at least 72 wt. %. ⋅withdrawing a steam effluent from the condensation-reaction step, and providing the steam effluent to a further condensation reaction in a further condensation apparatus to form a condensate comprising water. The present invention provides a robust and efficient process and system for removing lactide from a lactide-containing gas stream and recovering said lactide in a processable form. The process of the invention is able to handle feedstock with varying compositions and has a limited demand on energy and apparatus.