In chemical plants, packed towers are used for gas and liquid contact—like in absorption or distillation.
But sometimes, too much liquid builds up inside. This is called flooding.
Flooding can stop the process and damage the equipment.
In this article, we explain what flooding is, why it happens, and how to avoid it—step by step.
What Is Flooding in a Packed Tower?
Flooding happens when liquid can’t flow down properly inside the packed bed.
It builds up and fills the tower, making gas flow difficult.
It’s like a drain that’s clogged—the liquid has no place to go.
Signs of Flooding
- Sudden increase in tower pressure
- Liquid carryover into gas lines
- Strange noise or vibration in the tower
- Process efficiency drops
Why Flooding Happens
Flooding is usually caused by:
- Too much gas flow
→ High velocity pushes liquid back up - Too much liquid flow
→ The packing gets overwhelmed - Wrong packing design or damage
→ Bad liquid distribution or channeling - Foaming fluids
→ Foam makes the tower flood earlier - Blocked or dirty internals
→ Old scale or solids limit flow paths
How to Prevent Flooding
- Check gas and liquid flow rates are within design limits
- Use proper liquid distributors
- Choose suitable packing material
- Avoid over-foaming chemicals
- Regularly clean and inspect the tower
Pro tip: Many engineers check the flooding point during design. They run the tower at 60–80% of this limit for safety.
Conclusion
Flooding in packed towers is a common problem, but you can manage it by understanding the cause and controlling the process conditions.
As a beginner, learn to recognize the signs and always check your flow rates and packing design.
Prevention is much easier (and cheaper) than repair!