Case Study: Ozone Water Disinfection System for Major U.S. Airline

Overview:

A major U.S. airline partnered with Oxidation Technologies to implement an innovative ozone-based water disinfection system for its aircraft potable water systems. The solution was integrated into a custom-designed trailer, equipped with a gas generator, water holding tank, and ozone system, enabling mobile, self-sufficient disinfection on the tarmac. This case study details the implementation, process, benefits, and outcomes of the ozone disinfection system, addressing the airline’s need for efficient, safe, and environmentally friendly water treatment.

Background:

Commercial aircraft rely on potable water storage tanks to supply water for drinking, beverage and food preparation, handwashing, and toilet flushing. Maintaining water quality is critical to ensure passenger and crew safety, comply with U.S. EPA’s Aircraft Drinking Water Rule (ADWR), and prevent biofilm buildup in tanks and distribution lines. Traditional chemical disinfection methods, such as chlorine-based treatments (e.g., Purogene, sodium hypochlorite), are time-consuming, require extensive rinsing, and generate hazardous wastewater, leading to high labor costs and aircraft downtime. The airline sought a faster, more sustainable alternative to meet stringent safety standards while reducing operational costs.

Solution: Custom Trailer-Based Ozone Disinfection System:

Oxidation Technologies designed and supplied ozone water disinfection systems integrated into a custom trailer tailored to the airline’s specifications. The trailer was a self-contained mobile unit, featuring:

- Ozone System: A corona discharge ozone generator producing ozone gas on-site, injected into water via a venturi injector for efficient dissolution, creating ozonated water.

- Gas Generator: Provided electricity to power the ozone system and other components, ensuring operation in remote tarmac locations without external power sources.

- Water Holding Tank: Stored potable water for circulation or fill/drain processes, allowing flexible disinfection across various aircraft water system designs.

- Portability: The trailer was towable, enabling deployment to any aircraft on the tarmac, enhancing operational flexibility.

The system was compatible with two disinfection methods, accommodating diverse aircraft designs:

Fill/Drain Method:

- Fresh water with dissolved ozone was pumped from the trailer’s holding tank into the aircraft’s water tank, flowing through faucets, piping, and appliances to the drain.

- Once the tank was filled, ozonation ceased, and residual ozone naturally decayed to oxygen within 20–30 minutes, requiring no rinsing.

Water Circulation Method:

- Water was circulated from the aircraft’s tank to the trailer, where ozone was dissolved, and then returned to the aircraft.

- Circulation continued for 15–20 minutes until a target dissolved ozone level (e.g., 0.2–0.4 ppm) was achieved, after which ozone decayed naturally without additional flushing.

The system was automated, with ozone sensors monitoring concentrations to ensure effective disinfection (99.0% microbe reduction, per EPA’s ADWR) while preventing over-ozonation. Excess ozone gas was captured and destroyed using an activated carbon adsorber to ensure operator safety.

Implementation:

The ozone disinfection system was deployed across the airline’s fleet, tested on over 250 aircraft, including major commercial models. The trailer was positioned on the tarmac, connected to the aircraft’s water system via hoses, and operated by trained ground crew. The process was completed in 20–30 minutes per tank, compared to 8 hours for traditional chemical methods. The system’s portability and self-sufficiency allowed disinfection at any airport, regardless of local resources, streamlining maintenance schedules.

Benefits:

The ozone-based system offered significant advantages over chemical disinfection methods, aligning with the airline’s goals of efficiency, safety, and sustainability:

- Faster Disinfection: Ozone disinfected tanks and lines in 20–30 minutes, 16 times faster than the 8-hour chemical process, reducing aircraft downtime and labor costs. Ozone’s rapid oxidation (3,000 times faster than chlorine) ensured quick pathogen elimination.

- Biofilm Control: Ozone penetrated and destroyed biofilms in tanks, pipes, and appliances (e.g., coffee makers) without wetted contact, preventing bacterial regrowth and reducing maintenance needs.

- No Chemical Residues: Ozone decomposed into oxygen, eliminating the need for rinsing and ensuring taste- and odor-free potable water, enhancing passenger comfort.

- Environmental Sustainability: No hazardous wastewater was produced, simplifying disposal and reducing environmental impact. Eliminating chemical storage and transport minimized safety risks and carbon footprint.

- Cost Savings: Reduced disinfection time, water usage (no rinsing), and component corrosion (e.g., faucets, water heaters) lowered operational and maintenance costs. Field tests confirmed significant savings over chlorine-based methods.

- Regulatory Compliance: Achieved EPA’s ADWR standard of 99.0% microbe reduction, ensuring safe water for passengers and crew, with FDA-compliant ozone levels (aligned with bottled water standards).

Outcomes:

The ozone disinfection system transformed the airline’s water treatment process, delivering measurable improvements:

- Operational Efficiency: Disinfection time was reduced from 8 hours to 20–30 minutes, enabling faster turnaround times and increased aircraft availability.

- Cost Reduction: Lower labor, water, and maintenance costs resulted in substantial savings, validated by field tests across 250+ aircraft.

- Water Quality: Consistent achievement of potable water standards, with no chemical taste or odor, improved passenger satisfaction.

- Sustainability: The chemical-free process supported the airline’s environmental goals, reducing wastewater and chemical use.

- Scalability: The trailer’s mobility and compatibility with fill/drain and circulation methods ensured applicability across the airline’s diverse fleet.

Conclusion:

The custom trailer-based ozone water disinfection system, developed by Oxidation Technologies for a major U.S. airline, revolutionized aircraft water system maintenance. By leveraging ozone’s rapid oxidative power, the system achieved superior disinfection, biofilm control, and compliance with EPA standards in a fraction of the time required by chemical methods. The self-contained trailer design enabled flexible, on-tarmac deployment, while the elimination of chemical residues and wastewater aligned with sustainability objectives. This case study demonstrates ozone’s transformative potential in aviation water treatment, offering a model for other airlines seeking efficient, cost-effective, and environmentally friendly disinfection solutions.

For further inquiries about ozone systems for aircraft water disinfection, contact Oxidation Technologies at https://www.oxidationtech.com/contact/.