GPSA · Plant Processing of Natural Gas Ch. 3 · Solid Desiccant Dehydration
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Silica Gel Dehydration Calculator
Designs silica gel adsorption systems for gas dehydration to moderate dew points. Calculates bed sizing, regeneration requirements, and cycle times for moisture removal applications.
Feed Gas Conditions
MMSCFD
psia
°F
lb/MMSCF
Dehydration Specifications
lb/MMSCF
hours
Typical cycle: 8-16 hours on-stream
Silica Gel Properties
ft/min
Regular Density: Standard type, 6-8% capacity, economical
Design Results
Water Removal Rate-
Required Desiccant Mass-
Bed Volume-
Vessel Diameter-
Bed Height-
Regeneration Gas Required-
About Silica Gel Dehydration
Silica gel is an amorphous form of silicon dioxide with high porosity and surface area. It adsorbs water vapor from natural gas, providing deep dehydration suitable for cryogenic processing and pipeline applications.
Silica Gel Types
Regular Density: 6-8 wt% capacity, most economical
High Capacity: 10-12 wt% capacity, longer cycles
Indicating: Color change shows saturation, used in small units
Typical Performance
Outlet Dewpoint: -40 to -100°F
Cycle Time: 8-16 hours typical
Regeneration: 350-450°F for 2-4 hours
Bed Velocity: 20-40 ft/min
Advantages
Good for high-pressure applications
Lower regeneration temperature than alumina
Good mechanical strength
Can achieve very low dewpoints
Disadvantages
Liquid water causes damage (use inlet separator)
Lower capacity than molecular sieves
Can break down at high regeneration temps (>500°F)