VAPOR AND LIQUID DEHYDRATION
Recommended Products
Dryocel 848
Dryocel 850
Please contact the appropriate Porocel Office for Technical Data Sheets or Material Safety Data Sheets.
APPLICATION BULLETINS
11: Dehydration with Activated Alumina
13: On-Line Moisture Analysis
16: Thermal Regeneration of Fixed Bed Adsorbers
20: Water/Hydrocarbon Solubility Data
Please contact the appropriate Porocel Office if you would like to see Application Bulletins for our products or for a Porocel representative to contact you.
DESICCANT APPLICATIONS
Essentially any manufacturing facility requires dry air for operating pneumatic devices (valves, switches, etc…), providing good quality air purge for instrument enclosures, or as a general utility. Many other process gases are also commonly dehydrated with desiccant materials. These include nitrogen, hydrogen, natural gas, and carbon dioxide.
COMMON DEHYDRATION TECHNOLOGIES
Process stream dehydration, or dewpoint depression, can be accomplished by several different technologies:
- Refrigeration • Absorption • Deliquescence • ADSORPTION
ADSORPTION DESICCANT SELECTION
Activated aluminas
- High-to-moderate moisture concentration in feed
- Moderate-to-low effluent dewpoint required
- Moderate regeneration capability (heat) available
- Chemical resistance (ex: acids) required
- Liquid water entrainment probable
POROCEL Activated Alumina Desiccants:
DRYOCEL 848 / DRYOCEL 850
Silica gels and alumino-silicates
- High moisture concentration in feed
- Modest effluent dewpoint required
- Limited regeneration capability (heat) available
- Little or no concern of liquid water entrainment
Molecular sieves
- High-to-low moisture concentration in feed
- Very low effluent dewpoint required
- No limitation on regeneration capability (heat)
- Little or no concern of liquid water entrainment
In general, silicas and aluminas are used when initial adsorbate concentrations are high (>1% by volume) and complete removal is not required. Molecular sieves are best utilized with initially low adsorbate concentrations (<0.5%) and complete removal is mandated.
QUALITY AIR DRYER DESICCANTS PROVIDE:
Reliable air dryer operation:
High quality desiccants provide reliable operation of the air dryer. High quality desiccants offer high water-loading capacity, high crush strength and low attrition loss. Low quality desiccants can physically deteriorate in service and result in high pressure drop across the air dryer vessel. Once the desiccant has physically degraded, poor performance of the air dryer will require the replacement of the desiccant.
High water-loading capacity:
High quality desiccants balance the critical parameters of bulk density, surface area and porosity to allow more water to be removed per cycle. Low quality desiccant characteristics will not be optimized and, as a result, will display low water-loading capacity. A low capacity desiccant may allow water to enter the air system, causing corrosion, freezing or equipment malfunction.
Dust-free operation:
High quality desiccants exhibit low attrition loss. Low quality desiccants can create dust which will plug tubing, valves and gauges, requiring costly maintenance or replacement
Long service life:
High quality desiccants provide high water-loading capacity for a longer period of time. Longer service life saves money since desiccant replacement is required less frequently.