Electrolytic Cell for Sodium Hypochlorite Production

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current water treatment systems for making circulating water drinkable are restrictive due to high salt loads, hazardous chemical usage, complex maintenance requirements, and inefficiencies in hypochlorous acid production, particularly in systems using ion exchange membranes and electrochlorination methods.

Innovation Solution

A device that produces sodium hypochlorite or hypochlorous acid by electrolyzing salt-laden water directly in a cylinder connected to a water pipe, using bipolar electrolytic cells and a control unit to regulate production and safety, eliminating the need for intermediate tanks and reducing salt consumption, and incorporating remote monitoring for efficient operation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If ion exchange membrane systems are used to produce hypochlorous acid, then hypochlorous acid production is achieved, but the system becomes complex and requires fragile membranes that do not tolerate hard water

Engineering Contradiction:
Improvemembrane durabilityVSAvoidsystem complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent removes the ion exchange membrane from the system entirely, replacing it with a direct electrolysis cell that converts salt water directly to hypochlorous acid without requiring membrane separation. This eliminates the fragility and compatibility issues associated with membranes while simplifying the overall system structure.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The patent introduces a bipolar electrolysis cell as an intermediary device that directly converts salt water to hypochlorous acid through electrochemical reactions, eliminating the need for membrane-based separation and subsequent chemical mixing processes.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Productivity

If graphite electrodes are used in electrolysis systems, then electrolysis can be performed, but the electrodes have very short lifespan averaging 6 months

Engineering Contradiction:
Improveelectrolysis efficiencyVSAvoidelectrode lifespan
Core Design Contradiction:
ProductivityVSDuration of action of stationary object

Solution Approach 1:

The patent employs composite electrode structures with corrosion-resistant materials such as titanium or mixed metal oxides instead of pure graphite, combining the electrochemical activity needed for electrolysis with the durability required for long-term operation in harsh aquatic environments.

Inventive Principle:
Principle #40Composite materials

Solution Approach 2:

The patent optimizes electrolysis parameters including current density, voltage, and electrode surface area to reduce stress on electrodes while maintaining hypochlorous acid production efficiency, thereby extending electrode lifespan without sacrificing productivity.

Inventive Principle:
Principle #35Parameter changes

3Productivity

If salt is added directly to water for electrochlorination, then hypochlorous acid can be produced, but the salt load becomes excessively high at 2 to 7 grams per liter

Engineering Contradiction:
Improvehypochlorous acid productionVSAvoidsalt concentration
Core Design Contradiction:
ProductivityVSQuantity of substance

Solution Approach 1:

The patent replaces the mechanical mixing and dissolution process of adding large amounts of salt to water with an electrochemical conversion process that uses electricity to directly transform dissolved salt into hypochlorous acid, significantly reducing the required salt concentration while maintaining production efficiency.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent optimizes the electrochemical reaction parameters including current efficiency, voltage, and reaction time to maximize hypochlorous acid yield from minimal salt input, reducing the salt concentration requirement from 2-7 grams per liter to much lower levels.

Inventive Principle:
Principle #35Parameter changes

4Reliability

If venturi systems are used to evacuate gas during electrolysis, then gas removal is achieved, but the pipe diameter is reduced and flow rate decreases

Engineering Contradiction:
Improvegas evacuationVSAvoidwater flow rate
Core Design Contradiction:
ReliabilityVSSpeed

Solution Approach 1:

The patent removes the venturi system entirely by designing an electrolysis cell that produces minimal gas through direct electrochemical conversion, eliminating the need for complex gas evacuation mechanisms and their associated flow rate restrictions.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The patent uses a bipolar electrolysis cell as an intermediary that directly converts salt to hypochlorous acid with minimal gas byproduct, replacing the need for mechanical gas evacuation systems and maintaining full water flow rate.

Inventive Principle:
Principle #24Intermediary (Mediator)

5Reliability

If softeners or anionic resins are incorporated into the system, then calcium ions are captured, but the water flow rate is significantly reduced

Engineering Contradiction:
Improvesystem compatibility with hard waterVSAvoidwater flow rate
Core Design Contradiction:
ReliabilityVSSpeed

Solution Approach 1:

The patent removes softeners and anionic resin cartridges from the system by using a electrolysis process that is inherently tolerant of hard water conditions, eliminating the flow rate restrictions imposed by these filtration components.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The electrolysis cell directly treats hard water without requiring pre-treatment or filtration, allowing the system to handle calcium and other minerals in the water without compromising performance or flow rate.

Inventive Principle:
Principle #25Self-service

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 solution significantly reduces salt loads in water treatment systems, eliminates the need for hazardous chemicals, simplifies maintenance, and enhances the efficiency and safety of hypochlorous acid production, making it suitable for various water treatment applications while minimizing environmental impact.

Implementation Method 1

A low voltage current is sent to the electrodes to carry out electrolysis. During this electrolysis the NACL will decompose into two parts (HClO and OCl-

Methodology Applied
Scientific EffectElectrolysis: Electrolysis

Data Source

PatentEP2721198B1Device for manufacturing sodium hypochlorite or hypochlorous acid and water treatment system in general
Publication Date: 2019.04.03 MP TECHNIC SARL
  • EP2721198B1 patent drawingFigure 1
  • EP2721198B1 patent drawingFigure 2
  • EP2721198B1 patent drawingFigure 3

AI summary

The invention relates to a device for producing sodium hypochlorite or hypochlorous acid for water treatment, the device comprising: - a cylinder (16) for storing salt in solid form, adapted for being fed directly via a pressurized water pipe, and comprising one or more tubes that form one or more electrolytic chambers (15); - one or more electrolytic cells received in the electrolytic chambers (15); the tubes of the cylinders being perforated to allow the contacting of the electrolytic cells with the salt-saturated water while preventing the electrolytic cells from being short-circuited by the solid salt. The invention makes it possible to produce sodium hypochlorite or hypochlorous acid from salt-saturated water in a cylinder, connected directly to the pipe of the water to be treated without the latter being loaded with salt.