Gas-liquid Contact of Plastic Fillers
A brief overview of the gas-liquid contact mechanism of plastic fillers.
Gas-liquid Contact of Plastic Fillers
Plastic fillers have naturally hydrophobic surfaces, making it difficult for liquid films to spread uniformly. Mass transfer efficiency relies more on structural design than surface properties.
Liquid Film Formation
Plastic surfaces typically have a contact angle >90°, causing liquids to easily shrink into droplets or streams. A continuous liquid film can only form at high flow rates (spray density >15 m³/m²•h). Ceramic fillers have a contact angle <30°, allowing liquid film formation even at low flow rates.
Contact Morphology of Different Fillers
Packing Type | Liquid Film Morphology | Gas Flow | Mass Transfer Efficiency |
Pall Ring | Discontinuous, partially dry region | Tortuous turbulent flow | Relatively high |
Hollow Sphere | Coexistence of droplets and liquid film | Mixed flow | Moderate |
Cascade Ring / Haier Ring | Predominantly droplets | Predominantly straight flow | Relatively low |
Surface embossing and perforations can improve wettability and increase efficiency.
Liquid Flow Patterns
Film Flow: Continuous surface coverage, high efficiency (only at high liquid volumes)
Stream Flow: Flows down in strips, partially unwetted, moderate efficiency
Droplet Flow: Droplets fall, low efficiency (at low liquid volumes)
Comparison with Metals and Ceramics
Comparison | Plastics | Metals | Ceramic |
Wettability | Poor | Average | Good |
Low Liquid Volume Efficiency | Low | Medium | High |
Strengthening Method | Structural Design | Surface Treatment | Surface Spreading |
Operational Recommendations
Spray density > 15 m³/m²•h; efficiency drops significantly at low liquid volumes.
Control gas velocity to 60%-80% of the flooding gas velocity.
Plastic packing requires high liquid distribution; distribution points ≥ 150/m².
Summary
The gas-liquid contact of plastic packing can be summarized as follows: structural design compensates for insufficient wettability; high liquid volume ensures effective contact; low liquid volume results in low efficiency. Ceramic packing is preferred for low liquid volume conditions; plastic packing is preferred for high liquid volume and large airflow. Properly controlling the spray density is key to maximizing performance. We are a Chinese supplier of plastic packing. For more information, please contact us via email at annayu@169chem.net or WhatsApp at +8618909016373.