In HVAC systems, cooling towers, and industrial air handling units, moisture droplets in the airflow can cause serious coil and filter damage. Excess moisture accelerates corrosion, reduces filtration efficiency, and increases maintenance costs.
Mist eliminators—also known as drift eliminators or demisters—are engineered to remove these droplets from the air stream before they reach coils and filters, ensuring longer equipment life and better air quality.
The Problem: Moisture and Droplet Carryover
Moisture can enter HVAC and process systems from:
- Cooling coil condensate carryover
- Humidifier mist
- Outdoor air intake during rain or fog
- Process exhaust recirculation in industrial settings
If droplets pass through without removal, they can:
- Damage coils through corrosion and scaling
- Shorten filter lifespan by wetting the filter media
- Promote mold and bacterial growth
- Increase system pressure drop and energy use
How Mist Eliminators Work
Mist eliminators use blade profiles or mesh pads to change airflow direction and capture droplets through inertial impaction.
- Blade Type Mist Eliminators: Best for high airflow and large droplet removal (>20 microns).
- Mesh Type Mist Eliminators: Effective for fine droplet removal (2–5 microns) in lower velocity air streams.
Once droplets coalesce on the mist eliminator surface, they drain away, ensuring only dry air moves forward to coils and filters.
Benefits for Coils and Filters
- Corrosion Prevention – Keeps coils dry, reducing rust and pitting.
- Extended Filter Life – Prevents wetting and degradation of filter media.
- Energy Savings – Maintains optimal airflow with lower pressure drop.
- Improved Indoor Air Quality – Reduces mold and bacterial contamination.
- Reduced Maintenance Costs – Less frequent coil cleaning and filter replacement.
Material Selection for Coil & Filter Protection
- PVC – Lightweight, corrosion-resistant, cost-effective.
- FRP (Fiberglass Reinforced Plastic) – Durable and UV stable, ideal for outdoor installations.
- Aluminum – Lightweight with moderate corrosion resistance.
- Stainless Steel (304/316) – Best for high-temperature and corrosive air environments.
Installation Considerations
- Position upstream of coils and filters for maximum protection.
- Ensure proper drainage to prevent water re-entrainment.
- Match mist eliminator design to airflow velocity for optimal efficiency.
- Maintain regular cleaning to prevent fouling.
By removing harmful moisture droplets, mist eliminators significantly extend the life of coils and filters, improve energy efficiency, and maintain indoor air quality. Whether for HVAC systems, cooling towers, or industrial air handling units, the right mist eliminator ensures dry, clean airflow and protects your investment in air system components.