
10
Technical Specifications
How Does it Work? (seediagram1)
Moisturesaturatedcompressedairentersthe
coalescingprefilter(F1)whereaerosolsare
coalesced then drained via an automatic drain
system. The moist water vapor-laden inlet air
free of liquid water flows to the inlet of the dryer
throughtheAPV(AutomaticPistonValve)(V1)
which diverts the inlet air to one of the towers, in
thisexampletower(T1).Airflowsupwardthrough
the adsorbent bed removing the moisture vapor,
thedriedairflowexitsthetowerthroughtheoutlet
APVvalve(V2)flowingtotheoutletparticulate
afterfilter(F2)whichremovesparticulatesfrom
the air stream. Clean and dry air now flows to the
process air distribution system.
As one tower is drying air, the other tower will be
regenerating(purging)theadsorbentbed.Inthis
example,tower(T2)willberegenerating.Prior
toregeneration,theexhaustvalve(V4)isopened
and the tower is depressurized to near atmospheric
pressure, the tower will now be regenerating.
Duringtheregeneratingprocessasmallportionof
dryoutletcompressedairisused,15%onaverage
basedonstandarddesigncapacityof100psig,
100°Finletair,100°FambientairandPDPof
-40°F.Thedryregenerationairflowischanneled
throughtheoutletAPVvalvetotheregenerating
tower(T2)removingmoisturefromtheadsorbent
bedandexitstheregeneratingtower(T2)through
exhaustvalve(V4)andexhaustmufflertoambient.
Afterregenerationcycleiscomplete,valve(V4)
closescausingtower(T2)torepressurizetoline
pressure.
Next,thetowerswillswitchwhenexhaustvalve
(V3)openscausingtower(T1)todepressurizeand
regenerate,simultaneouslytheinletandoutletAPV
valves(V1)and(V2)willshiftthepistonstothe
lowpressuretower(T1)causingtheinletairflow
tobedivertedtotower(T2)whichwillnowbethe
drying tower. This switching process will continue
repeatedly.
The dryer control system is completely automatic
and cycles the system through the drying and
regeneration cycles. The standard cycle drying time
is5minutes,regenerationcycleis4minutes,and
repressurizingcycleis1minute.
TheAircelAHLDE-SeriesHeatlessDryer
incorporates a unique energy saving control system
to reduce purge air loss with its integrated Energy
ManagementPurgeReductionSystemwhichutilizes
a moisture sensor sampling the air from mid bed of
theon-streamdryingtower,afterthefixedpurge
time is complete the regenerating/purging tower will
repressurize.Ifthemoisturesensorsensesalow
moisture condition or low load in the drying tower,
the drying tower will remain in the drying mode
afterthefixeddryingtimecycleforanextended
period of time. The end result is an overall purge
reduction and significant energy savings.
CAUTION!
• Donotmisuseormodifyunderany
conditions.Misuseormodification
of this equipment may result in
personal injury.
AircelAHLDE-Series-Models70-750