Feed Gas Conditions

Gas Flow Rate

MMSCFD

Operating Pressure

psia

Inlet Temperature

°F

Inlet Water Content

lb/MMSCF

Dehydration Specifications

Target Outlet Water Content

lb/MMSCF

Target Cycle Time

hours

Typical cycle: 8-16 hours on-stream

Silica Gel Properties

Silica Gel Type

Design Bed Velocity

ft/min

Regular Density: Standard type, 6-8% capacity, economical

📚 Learn the Theory

Comprehensive coverage of silica gel adsorption, regeneration cycles, and comparison with molecular sieves.

Read Engineering Guide →

Design Results

Water Removal

Water Removal Rate -

Water per Cycle -

Outlet Dew Point (est.) -

Bed & Vessel Sizing

Required Desiccant -

Bed Volume -

Vessel Diameter -

Bed Height -

L/D Ratio -

Operating Conditions

Actual Velocity -

Pressure Drop -

Regeneration

Heat Duty -

Regen Gas Flow -

Recommended Beds -

Design Methodology

This calculator uses GPSA Section 20 methods for solid desiccant dehydration with Ergun equation for pressure drop and heat balance for regeneration sizing.

Key Design Parameters

L/D Ratio: 2:1 to 4:1 for good flow distribution
Velocity: 20-40 ft/min (avoid fluidization)
Pressure Drop: < 5 psi clean bed
Safety Factor: 1.25× for MTZ losses

Dynamic Capacity (at operating conditions)

Regular: 6-8 wt% @ 100°F, 800 psia
High Capacity: 10-12 wt%
Indicating: 5-6 wt% (color indicator reduces capacity)

Regeneration Requirements

Heating: 350-450°F for 2-4 hours
Cooling: 2-3 hours to < 120°F
Direction: Counter-current to adsorption
Gas Rate: 5-15% of feed flow

Critical Design Notes

Install inlet separator - liquid water damages bed
Use outlet filter to capture fines
Monitor ΔP rise - indicates bed degradation
Max regen temp 450°F (silica gel degrades above 500°F)

When to Use Molecular Sieve Instead

Outlet dew point < -60°F required
Upstream of LNG or cryogenic processing
Must not co-adsorb hydrocarbons (use 3A type)

Silica Gel Dehydration Calculator