Optimizing Operating Conditions for Reliable Ozone Removal

 

 

The performance of an ozone decomposition catalyst is highly dependent on its operating environment. By controlling key engineering parameters, it is possible to achieve >99% ozone conversion efficiency, protect downstream equipment, and extend the catalyst’s service life.

 

This guideline is based on DEAI CHEM’s field installations and verified industry test data — including the behavior of MnO₂-based catalysts under high-humidity conditions. It is suitable for municipal water treatment, plasma exhaust applications, corona discharge off-gas treatment, and ozone disinfection systems.

 

 

DEAI CHEM offers granular, spherical, and powder-grade catalysts, including custom-coated substrates. The following five critical operating parameters are essential to maintaining catalyst stability during continuous operation:

 

 

 

 

1. Vessel Orientation & Flow Direction – Vertical Downflow for Uniform Contact

 

 

For consistent gas–catalyst interaction, a vertically oriented vessel with top-down gas flow is recommended. Gravity assists in distributing the gas evenly across the catalyst bed, reducing channeling and dead zones. This configuration is ideal for long-term, continuous industrial operation.

 

Engineering Benefits:

 

• Enhances gas distribution and mitigates localized overloading

• Minimizes pressure drop and energy consumption

• Achieves >98% conversion in large-scale municipal off-gas installations

 

 

 

 

2. Material Compatibility – Preventing Oxidative System Degradation

 

 

Ozone is highly oxidative and can degrade elastomers and non-resistant alloys. All components — vessel walls, seals, piping, and filters — must be built from ozone-compatible materials to prevent leakage or premature failure.

 

Recommended Materials:

 

• Stainless steel 316L (excellent compatibility, Grade A) or titanium alloys for vessels and piping.

 

• Glass-filled polymers or PTFE (Grade A) for seals and fittings.

 

• Avoid: Buna N rubber (Grade D) and carbon steel (Grade D) due to severe degradation in ozone environments.

 

 

DEAI CHEM’s catalyst systems have been validated to operate reliably with these materials for over 10 years without leakage or structural degradation.

 

 

 

 

3. Gas Hourly Space Velocity (GHSV) — Maintain ≤5,000 hr⁻¹

 

 

The Gas Hourly Space Velocity (GHSV) is defined as the ratio of gas volumetric flow rate to the catalyst bed volume (hr⁻¹). To ensure sufficient residence time, DEAI CHEM recommends maintaining ≤5,000 hr⁻¹.

 

Performance Data:

 

• At ≤5,000 hr⁻¹, with inlet ozone at 10–45 ppm, conversion exceeded 98% for over 100 hours.

• Beyond 10,000 hr⁻¹, efficiency may drop below 90%, especially under variable flow conditions.

• Design guideline: Maintain 20% safety margin for fluctuating ozone loads.

 

 

 

 

4. Linear Velocity — ≥0.66 m/sec to Prevent Stagnant Zones

 

 

A minimum linear velocity of 0.66 m/sec (2.2 ft/sec) is recommended to maintain turbulent flow and prevent catalyst bed stagnation.

 

Engineering Advantages:

 

• Prevents channeling and improves bed utilization

• In plasma exhaust streams (20–50 L/min), maintains residual ozone <1 ppm

• If pressure drop exceeds 0.1 bar, airflow should be reevaluated

 

 

 

 

5. Humidity Management — Preheat Gas by 9°C to Avoid Catalyst Deactivation

 

 

In high-humidity environments, condensed moisture can temporarily deactivate catalytic sites, especially those with acidic functionality. To prevent this, the inlet gas should be preheated by at least 9°C (15°F) above ambient temperature prior to entering the catalyst bed.

 

Implementation Notes:

 

• A simple heat exchanger is usually sufficient

• At 90% relative humidity, this approach reduces performance loss to <10% within 6 hours

• If NOx is present, elevated temperature (>100°C) is advised

 

 

 

Engineered for Long-Term Reliability — Passive Operation, Minimal Maintenance

 

By incorporating the above operating parameters, ozone decomposition systems can achieve:

 

• >5 years catalyst lifetime

• Low pressure drop and energy efficiency

• Compliance with regulations such as the EU REACH framework and the U.S. Clean Air Act

 

 

DEAI CHEM’s MnO₂–CuO-based catalysts (e.g., 4×8 mesh irregular granules) have been successfully deployed in industrial air treatment systems, consistently converting ozone to oxygen with no harmful by-products.

 

 

 

Application Examples

 

• Municipal off-gas treatment: Preheating + controlled GHSV achieved >99% removal and reduced atmospheric emission levels.

• Industrial exhaust: Fully compatible with stainless-steel vessels and operational for >10,000 hours with no catalyst replacement.

 

 

 

If you require assistance with system sizing, catalyst selection, or installation design, our technical team can support your project from evaluation to implementation.

 

Contact DEAI CHEM for engineering guidance and catalyst integration support.