Silica gel is a spherical bead consisting of 97-100% silica. It is available in two types:
1. Indicating, a translucent bead impregnated with blue color and
2. Non-indicating white translucent color.
Sorbead R is an alumina-silicate, although it is listed in the silica gel section it is not truly a silica gel. Sorbead R is designed to perform in difficult environments and provide a higher service life than white silica gel. It is sometimes referred to as brown silica gel.
Since silica gel fractures in the presence of liquid water, it must be protected by a 10% to 15% (by weight) layer of activated alumina as a water buffer on the inlet side of the desiccant bed.
Dew points of -40 F and lower may be achieved with silica gel depending on dryer design and operating conditions.
FEATURES & BENEFITS:
- High moisture retention capacity under dynamic conditions: Used in some heated type regenerative dryers. Under dynamic conditions, a higher design capacity rating and lower regeneration temperature can be used.
- Uniform bead shape: This shape provides lower pressure drop and less abrasion than granular types. Smooth beads also pack uniformly to minimize channeling.
- Provides visual check of desiccant condition (indicating type only): Beads are impregnated with a moisture indicator. The color changes from blue to pink or yellow to green as moisture is adsorbed.