CDI Filter Electrode Fouling Control via Polarity Reversal
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
CDI type water treatment apparatuses face performance deterioration due to fouling on electrodes, which existing technologies have not effectively addressed.
Innovation Solution
A CDI water treatment apparatus with a dual filter system and a valve control unit that reverses the flow direction of raw water during purification to remove fouling from electrodes, ensuring continuous purification and recycling modes without compromising purified water quality.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If ions are continuously adsorbed on electrodes during purification, then purification performance is improved, but electrode fouling increases and filter performance deteriorates
Solution Approach 1:
The patent implements periodic switching between purification mode and electrode recycling mode. During purification mode, ions are adsorbed on electrodes to treat water. When fouling accumulates, the system switches to recycling mode where electrode polarity is reversed to desorb accumulated ions, thereby removing fouling. This periodic alternation maintains both high purification performance and prevents electrode degradation.
Solution Approach 2:
The patent recovers electrodes by reversing their polarity during dedicated recycling periods. Instead of discarding fouled electrodes, the system applies reverse voltage to desorb accumulated ions from the electrode surfaces, restoring electrode performance and extending their service life while maintaining continuous operation capability through dual electrode sets.
2Reliability
If electrode recycling is performed to remove fouling, then electrode performance is restored, but purified water production is interrupted
Solution Approach 1:
The patent divides the electrode system into two independent sets (first electrodes and second electrodes) that can operate independently. While one set undergoes recycling to remove fouling, the other set continues purification operations. This segmentation allows electrode maintenance without interrupting purified water production, as the system can switch between the two electrode sets seamlessly.
Solution Approach 2:
The patent ensures continuous purified water production by maintaining one electrode set in purification mode while the other undergoes recycling. The control unit automatically switches between the two sets, ensuring that purification operations never stop. This continuity eliminates downtime and maintains constant productivity while still performing necessary electrode maintenance.
3Device complexity
If a single CDI filter is used, then device complexity is reduced, but continuous operation capability is compromised
Solution Approach 1:
The patent segments the single CDI filter into two independent electrode sets (first and second electrodes) with separate inlets and outlets. Each set can independently perform purification or recycling operations. This segmentation enables one set to work while the other is being recovered, providing continuous operation capability without significantly increasing overall system complexity.
Solution Approach 2:
The patent combines two electrode sets within a single filter housing, integrating multiple functions into one device. The housing contains both purification and recycling pathways, allowing the system to perform both operations simultaneously using different electrode sets. This merging approach achieves continuous operation capability while keeping the device structure relatively compact and unified.
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 apparatus effectively prevents filter performance deterioration by removing fouling from electrodes, maintaining the quality of purified water and enabling continuous operation through controlled valve management.
Implementation Method 1
The CDI method means a method for removing ions (contaminants) by using a principle that ions are adsorbed and desorbed on the surfaces of electrodes by an electrical force
Implementation Method 2
When brine water (or raw water) including ions with a voltage applied to electrodes is made to pass between electrodes, negative ions move to a positive electrode, and positive ions move to a negative electrode
Implementation Method 3
it is necessary to recycle the electrodes by desorbing ions adsorbed to the electrode
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A CDI type water treatment apparatus according to the present invention includes: a CDI filter unit which discharges purified water in a purification mode for purifying raw water, discharges recycle water in a recycle mode for recycling electrodes, and includes a water inlet port through which the raw water is introduced and a water outlet port through which the purified water or the recycle water is discharged; a supply unit for supplying the raw water to the CDI filter unit; a dispensing unit for dispensing the purified water to a user; a discharge unit for discharging the recycle water to the outside; a valve unit including a supply valve disposed on a flow path from the supply unit to the water inlet port, a discharge valve disposed on a flow path from the water outlet port to the discharge unit, a dispensing valve disposed on a flow path from the water outlet port to the dispensing unit, a cleaning unit disposed on a flow path from an upstream side of the supply valve to the water outlet port, and a drain valve disposed on a flow path from a downstream side of the supply valve to the outside; and a control unit for controlling opening or closing the valves of the valve unit.