CO2 Electrolysis Stack Corrosion Protection via Inert Gas
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Electrolysis stacks, particularly CO2 electrolysis stacks, face challenges in preventing corrosion during standby and transport due to stray and load currents, which require high energy expenditure or complex solutions like continuous electrical connections or inert conduit incorporation, making them inefficient and prone to oxidation.
Innovation Solution
The method involves partially emptying electrolytes from electrolysis stacks and replacing them with inert gases like CO2 or mixtures containing inert gases and liquid droplets, which interrupts current flow and reduces corrosion risk without the need for continuous electrical power or complex infrastructure.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a sufficiently high standby current is supplied to prevent oxidation of electrodes, then corrosion protection is improved, but energy consumption increases considerably
Solution Approach 1:
The patent extracts the electrolyte from the electrolysis cells and replaces it with an inert gas during standby operation. This removes the conductive medium that enables harmful current flow, thereby eliminating corrosion risk without requiring continuous high standby current supply.
Solution Approach 2:
The patent introduces an inert gas atmosphere into the electrolysis cells to replace the electrolyte during non-operational periods. This inert environment prevents electrochemical reactions and oxidation of electrodes, providing corrosion protection without energy consumption.
2Use of energy by moving object
If individual cell potential control is implemented to avoid elevated energy expenditure, then energy consumption is reduced, but apparatus complexity increases due to required electrical connections
Solution Approach 1:
The patent removes the electrolyte from the system during standby, eliminating the need for complex individual cell potential control systems. Without electrolyte present, there is no conductive path for stray currents, so sophisticated electrical connection infrastructure becomes unnecessary.
3Object-generated harmful factors
If long electrolyte conduits of low cross section are incorporated to minimize stray current, then stray current is reduced, but device complexity and performance compromise increase
Solution Approach 1:
The patent replaces the electrolyte in conduits with inert gas during standby operation. This eliminates the conductive medium in the conduits, thereby minimizing stray current without requiring complex conduit design modifications such as long paths or restricted cross-sections.
4Speed
If electrolyte is continuously present in the stack, then operational readiness is maintained, but corrosion risk increases due to stray currents in manifold connections
Solution Approach 1:
The patent implements a dynamic system where the electrolyte presence is changed based on operational state. During standby, electrolyte is removed to prevent corrosion; during operation, electrolyte is reintroduced to enable electrochemical reactions. This dynamic adjustment optimizes both protection and readiness.
Solution Approach 2:
The patent performs preliminary removal of electrolyte before standby periods begin, and preliminary introduction of electrolyte before operation resumes. This ensures that the stack is in the appropriate state (corrosion-protected or operationally ready) before the respective phase commences.
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 approach effectively prevents corrosion in non-operational CO2 electrolysis stacks and during transport, reducing energy consumption and eliminating the risk of explosion, while allowing for shutdown without electrical power and without the need for heating devices to prevent electrolyte freezing.
Implementation Method 1
at least partly emptying the electrolyte from parts of at least the first electrolysis cell and/or of the at least one first feed and/or of the at least one first drain... effectively prevents corrosion in non-operational CO2 electrolysis stacks
Data Source
AI summary
A method of protecting a nonoperational CO2 electrolysis stack from corrosion, includes: at least partly emptying an electrolyte from parts of a first electrolysis cell and/or of a first feed and/or of a first drain and/or of an overall feed which is connected to the first feed and the second feed and is designed to provide an inlet for the first feed and the second feed and/or of an overall drain which is connected to the first drain and the second drain and is designed to provide an outlet for the first drain and the second drain. The electrolyte which is removed by the at least partial emptying is exchanged for an inert gas or a mixture including an inert gas and liquid droplets present therein, wherein the inert gas is CO2.