Electrochemical reactor and its cleaning or regeneration
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing electrochemical reactors for dye reduction, particularly for vat and sulfur dyes, face inefficiencies due to high reducing agent consumption, toxic sulfite/sulfate loading in effluents, large electrode surfaces, low economicity, and lack of effective regeneration methods, leading to rapid decline in electrode efficiency and maintenance challenges.
Innovation Solution
An electrochemical reactor design featuring multiple stacks of electrolytic cells with parallel connections, allowing for separate washing and regeneration of electrodes during batch operations, using freely suspended conductive granules and circulation of cleaning solutions to maintain electrode efficiency and extend lifecycle.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If conventional reduction agents (hydrosulfite, thiourea dioxide) are used for vat dye reduction, then the reduction process can be achieved, but high sulfite/sulfate loading is generated in the effluent which is toxic and corrosive
Solution Approach 1:
The patent replaces chemical reduction agents with an electrochemical reduction system. Instead of using hydrosulfite or thiourea dioxide that generate sulfite/sulfate waste, the invention uses electrical current to reduce vat dyes directly at the electrode surface, substituting a chemical system with an electrical one. This eliminates the harmful sulfite/sulfate loading in effluent while maintaining effective dye reduction.
Solution Approach 2:
The invention changes the fundamental parameter of the reduction process from chemical reagent-based to electricity-based. By applying controlled electrical potential to the electrode, the reduction occurs through electron transfer rather than chemical reaction with reducing agents, fundamentally changing the reaction mechanism and eliminating the generation of sulfite/sulfate waste products.
2Loss of substance
If electrochemical methods are used for dye reduction, then reducing agent consumption is reduced, but very large electrode surfaces are required and efficiency is low
Solution Approach 1:
The patent employs a porous electrode structure with high surface area to volume ratio. The porous material provides numerous active sites for electrochemical reactions, significantly increasing the effective electrode surface area without requiring a large physical footprint. This allows efficient dye reduction with compact electrode dimensions, resolving the contradiction between low reducing agent consumption and large electrode surface requirements.
Solution Approach 2:
The invention transitions from planar electrode geometry to a three-dimensional porous structure. By utilizing the internal surface area of porous materials, the effective reaction surface is expanded into the third dimension, providing high catalytic activity within a compact volume and eliminating the need for very large electrode surfaces.
3Productivity
If electrochemical reactors operate for extended periods, then productivity is maintained, but electrode efficiency declines rapidly requiring frequent maintenance
Solution Approach 1:
The patent incorporates a preliminary cleaning action by integrating a cleaning electrode system that operates periodically to remove deposits from the working electrodes. Before the working electrodes become fouled and lose efficiency, the cleaning electrodes are activated to restore their surface, preventing efficiency decline and maintaining continuous productivity without frequent maintenance interruptions.
Solution Approach 2:
The invention implements a self-service mechanism where the reactor system automatically cleans its own electrodes through integrated cleaning electrodes and circulation systems. The system monitors and maintains its own performance by periodically activating cleaning functions, eliminating the need for external maintenance intervention and ensuring continuous reliable operation.
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 reactor achieves reduced reducing agent consumption, minimized toxic effluent generation, increased electrode efficiency, and extended maintenance intervals, enabling continuous operation with improved reaction surface area and reduced pressure loss, thus enhancing the industrial viability of dye reduction processes.
Implementation Method 1
Direct electrochemical reduction of indigo via the indigo radical has been proposed as an alternative to mediated electrochemical reduction
Implementation Method 2
catholyte solution is circulated through the remaining one or more stacks
Data Source
Figure 1
Figure 2a~2b
Figure 3
AI summary
An electrochemical reactor suitable for reducing dye to leucodye, comprises at least four electrolytic cells (4), wherein the electrolytic cells (4) are provided in the form of at least two stacks (5) of at least two electrolytic cells (4) each such that one stack at a time can be separated for cathode or anode regeneration during suspension preparation.