Alumina Silica Gel – optimized for compressed air and gas drying.
Standard silica gel quickly reaches its limits under demanding conditions. The GIEBEL Poresphere® AL series is just getting started.
Improved mechanical stability >200 N
Higher H₂O adsorption capacity of up to 44%
Perfect for demanding and fluctuating conditions
From this point on, it becomes too much for pure silicon dioxide.
Compressed air treatment and gas drying impose specific requirements on drying processes.
The desiccant beads are subjected to significant mechanical stress. High volumetric flow rates, continuous operation involving regeneration cycles, and fluctuations in temperature and humidity create a harsh environment.
Standard silica gel, typically used for air drying in breathers or other static applications, simply cannot withstand these conditions.
Increased abrasion and wide moisture ranges place an extreme strain on the silicon dioxide structure of these small beads.
Al₂O₃ adds strength. Even to silica gel.
To enhance adsorption properties, a certain amount of aluminum oxide (Al₂O₃) is added to the raw silicon dioxide material. Even a small addition yields significant results:
Mechanically robust
The Al₂O₃ content reinforces the structure of the beads, allowing them to withstand greater mechanical stress. A crucial factor during repeated regeneration cycles.
Absorbs water more effectively than standard silica gel at higher humidity levels (80–90% RH). Ideal for fluctuating environmental conditions.
Higher H₂O capacity
Increased maximum adsorption capacity of up to 44% at 80% relative humidity.
Water-resistant
With an Al₂O₃ content of > 10%, silica gel is generally considered resistant to contact with liquid water. Pure silicon dioxide beads would fracture under such conditions.
Two variants for two tasks.
PORESPHERE® AL-H
High-performance desiccant with 3.4% Al₂O₃
- High pressure & high volume flow rates
- Frequent & intensive regeneration
- Fluctuating conditions
- Primary layer for adsorption dryers, gas drying, and compressed air applications
PORESPHERE® AL-W
Water-resistant protective layer with 13.5% Al₂O₃
- Resistant to contact with liquid water droplets (condensate)
- Used as a protective layer in a combined bed with AL-H (20% / 80%)
- Ensures uniform air/gas flow due to its structural stability
Why you need water resistant silica gel.
Standard silica gel beads are designed for water vapor, not for liquid water. If the beads touch liquid water anyway, the pores flood all at once and their structure begins to crack and the beads break.
To prevent this, a protective layer of water resistant silica gel bead is used which stays structurally stable – evene after touching liquid water.