Filter
Top Products
350-2100 cfm Dryers Chapter 2: Functional Description 13 of 58
2-5 The Closed Loop Drying System
ACS dryers force hot, dry air through the resin in the drying hopper, where the air picks up
moisture from the material and is drawn back to the dryer.
In the dryer, moisture is stripped from the air by a desiccant bed. The dried process air is then
re-heated and delivered back into the drying hopper to dry material again.
This system is a "closed loop", because ambient (outside) air is never introduced into the
process air. The closed loop system is used by ACS because the process air is typically much
drier than ambient air, even after carrying moisture out of the plastic resin. Recycling process
air maintains drying efficiency at a consistently high level.
Figure 1: WD/SDA/CDA 350-2100 Dryer Specifications
Model
Number
Amp
Draw
Dimensions
(Inches)
Hose
Connection
(Inches)
Shipping
Weight
Process
Blower
Regen
Blower
Desiccant
Lbs./Bed
460-3-60 L W H I.D. Lbs. Hp. Hp. Large Small
350 56 56 73 4 1000 5 ½ 30 76
350-RT 56 56 73 4 1000 5 ½ 30 76
425 61 52 82 5 1100 7½ ½ 30 90
425-RT 61 52 82 5 1100 7½ ½ 30 90
500 63 66 94 5 1200 7½ ¾ 40 100
500-RT 63 66 94 5 1200 7½ ¾ 40 100
600 58 56 88 6 1450 10 ¾ 40 120
600-RT 58 56 88 6 1450 10 ¾ 40 120
700 59 66 93 6 1600 10 ¾ 40 135
700-RT 59 66 93 6 1600 10 ¾ 40 135
850 103 88 84 90 8 3 ¾ 120 120
850-RT 141 88 84 90 8 3 ¾ 120 120
1000 113 88 84 90 8 7½ ¾ 120 130
1000-RT 146 88 84 90 8 7½ ¾ 120 130
1250 138 88 84 90 8 7½ ¾ 120 180
1250-RT 194 88 84 90 8 7½ ¾ 120 180
1500 156 94 100 90 8 7½ ¾ 120 240
1500-RT 213 94 100 90 8 7½ ¾ 120 240
1800 179 94 100 90 8 10 ¾ 120 310
1800-RT 235 94 100 90 8 10 ¾ 120 310
2100 203 94 100 98 10 15 ¾ 120 360
2100-RT 278 94 100 98 10 15 ¾ 120 360
2-6 What is Desiccant?
Desiccant is a material which attracts and holds (absorbs) water from the air. The desiccant
ACS dryers use is a synthetic crystalline metal aluminosilicate that is blended with a clay
binder and formed into beads.
Absorbed water is driven from saturated desiccant by heating it to a high temperature
(reducing the desiccant's capacity to hold water) and forcing air through it. This moisture
removal process is called "regeneration".
2-7 The Process/Regeneration Cycle
ACS dryers have two desiccant beds. While one bed is on-line in the process air loop, the
other is off-line being regenerated.