Purification of spent deicing fluid by membrane techniques

Area of Science:

• Environmental Engineering
• Chemical Engineering
• Materials Science

Background:

• Spent deicing fluid poses environmental challenges and represents a significant operational cost for airports.
• Current disposal methods are costly and environmentally suboptimal.
• Effective recycling of deicing fluid is crucial for sustainable aviation operations.

Purpose of the Study:

• To develop and assess a membrane-based concept for purifying and concentrating spent deicing fluid.
• To evaluate the techno-economic feasibility of implementing this recycling concept at airports.
• To identify key cost factors influencing the economic viability of deicing fluid recycling.

Main Methods:

• A multi-stage membrane process including microfiltration, nanofiltration, reverse osmosis, and membrane distillation.
• Techno-economic assessment (TEA) based on a case study at a medium-sized airport.
• Analysis of impurity removal efficiencies and glycol concentration levels.

Main Results:

• Achieved efficient removal of solid/colloidal impurities (~95%) and deicing fluid additives like colorants (~90%) and surfactants (~93%).
• Concentrated purified deicing fluid to ~60 wt% glycol solution, suitable for reuse.
• TEA indicated economic feasibility when propylene glycol prices exceed 1,000 EUR/tonne, with labor and fluid consumption as key cost drivers.

Conclusions:

• The membrane-based recycling concept offers an effective and economically viable solution for spent deicing fluid.
• Integration with existing airport operations can further enhance cost-effectiveness.
• This approach supports environmental sustainability and reduces operational costs in aviation.