Activated
alumina is a porous form of aluminum oxide. It has a high
surface area which adsorbs vapors without any change in
form. Activated aluminas will not soften or disintegrate
easily when immersed in water.
Dew points to -40°F and lower may be achieved with activated
alumina depending on dryer design and operating conditions.
• The 1/8 (2-5mm) bead is the size most frequently
used in
• regenerative dryers.
• The 3/16 (4-8mm) bead is used when pressure drop
and surface area requirements fall between
• 1/8” and 1/4”
material. It is suitable for most systems.
• The 1/4 (5-10mm) bead alumina is used both as a
pre-bed material to support large desiccant beds
• or as a buffer for
silica gel beads. Pressure drop is slightly lower than 1/8”
(2-5mm) material.
If size is not known or specified, the 1/8” (2-5mm)
size is usually satisfactory. However, if activated alumina
is used in a regenerative dryer and the desiccant retaining
screens cannot be measured, the 1/4” (5-10mm) size
should be used as a bed support (6” layer). If at
all possible, obtain a sample material and measure it before
ordering.
Physical
Properties |
|
1/8"
(2-5mm) |
3/16"
(4-8mm) |
1/4"
(5-10mm) |
| Color
and form |
White
bead |
White
bead |
White
bead |
| Bulk
Density |
48
lbs/cu.ft. |
48
lbs/cu.ft. |
48
lbs/cu.ft. |
| Crush
strength |
17-30
lbs |
45-60
lbs |
50-70
lbs |
| Surface
area |
1.74
x 10 6 sq ft/lb |
1.65
x 10 6 sq ft/lb |
1.59
x 10 6 sq ft/lb |
| |
|
|
|
| Static
adsorption |
|
|
|
| Humidity |
|
|
|
| 100%
RH |
42.0% |
40.0% |
36.0% |
| 90%
RH |
37.5% |
35.0% |
32.0% |
| 60%
RH |
21.0% |
21.0% |
17.5% |
| 10%
RH |
7.5% |
7.0% |
6.0% |
|
|
|
Activated
Alumina 1/8" |
Activated
Alumina 3/16" |
Activated
Alumina 1/4" |
Activated
Alumina Package Sizes |
| 1/8"
(2-5mm) |
3/16"
(4-8mm) |
1/4"
(5-10mm) |
| 33-0237 |
25
lb pail |
33-0370 |
25
lb pail |
33-0240 |
25
lb pail |
| 33-0238 |
50
lb bag |
33-0367 |
50
lb bag |
33-0241 |
50
lb bag |
| 33-0320 |
375
lb steel drum |
33-0371 |
375
lb steel drum |
33-0321 |
375
lb steel drum |
| 33-0266 |
2000
lb bulk bag |
33-0372 |
2000
lb bulk bag |
33-0267 |
2000
lb bulk bag |
1.
High adsorption capacity
With high surface area and excellent pore distribution,
activated alumina has a high water adsorption capacity.
This reduces initial cost, energy consumption and operating
costs through smaller bed sizes and/or longer operating
cycles.
2. Low abrasion
Insures less dusting during tower depressurization or loading.
Low abrasion means low pressure drop and a reduced chance
of plugging the afterfilter.
3. Resists liquid water
Water slugging due to upstream failure of aftercooler, separators
or drain traps will not fracture the alumina beads. The
adsorption capacity of the desiccant can be restored after
complete regeneration.
4. High crush stregnth
High crush strength, which limits dusting, is important
during loading of desiccant towers. High crush strength
makes alumina effective as a prebed material when used with
other types of desiccants.
5. Uniform bead sizes
Activated alumina is a uniformly sized bead. It provides
low pressure drop to minimize channeling and ensures utilization
of the full bed column section.
