The main maintenance challenges for liquid air energy storage (LAES) systems include:
- Oxygen enrichment and fire/explosion risk: During operation and especially after downtime, preferential boiling of nitrogen can lead to local oxygen enrichment in parts of the system, such as feed pipes to cryogenic pumps. This oxygen enrichment poses a fire or explosion risk if it comes into contact with hydrocarbons like lubricating oil used in the power turbine. To manage this, components must be oxygen cleaned, and purging of pipes before restarting operation is necessary to clear enriched fluids.
- Thermal store management: Operating the thermal energy storage at low pressure is used to overcome difficulties associated with manufacturing large pressurized stores. Proper management of the thermal store is essential for system safety and performance.
- Material and component durability under cryogenic conditions: LAES systems involve handling and storing liquid air at very low temperatures, which can challenge materials and components, requiring specialized maintenance approaches to prevent failures.
- Complexity of maintaining cryogenic systems: The liquefaction and energy recovery processes in LAES are complex and involve cryogenic equipment requiring close monitoring and upkeep to prevent efficiency losses and ensure safe operation.
- Purging and preventing stratification issues: While long-term stratification or bulk liquid air enrichment in storage tanks has not been observed over years of operation, maintaining uniform composition and preventing local variations through regular purging and monitoring is a key maintenance consideration.
Overall, LAES systems require specialized maintenance to address oxygen safety hazards, manage cryogenic thermal storage integrity, and ensure reliable performance of complex cryogenic equipment. These factors constitute the primary operational challenges behind maintaining liquid air energy storage facilities.
Original article by NenPower, If reposted, please credit the source: https://nenpower.com/blog/what-are-the-main-maintenance-challenges-for-liquid-air-energy-storage-systems/
