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4. INSTALLATION
4.1 Location in the compressed air system
NOTE: The air compressor should be adequately sized to handle
air system demands as well as purge loss. Failure to take this into
account could result in overloading air compressors and/or insufcient
air supply downstream. It is desirable to install the dryer where the
compressed air is at the lowest possible temperature (downstream of
aftercoolers) and the highest possible pressure (upstream of pressure
reducing valves) without exceeding the maximum operating pressure
of the equipment. (Refer to Figure 4-1)
4.1.4 Heatless Pressure-Swing Desiccant Air Dryer
4.1.5 Afterlter(s) –
To ensure downstream air purity (prevent desiccant dust from
traveling downstream) adequate ltration downstream of the dryer
is required.
• First Afterlter - Particulate Removal -Typically 1-micron ltration
is specied although ner ltration is available.
• Second Afterlter - Oil Vapor Adsorption -This lter is used to
remove oil vapor and its subsequent taste and odor and to protect
down-stream components from solid particles 0.01 micron and
larger.
NOTE: By-pass lines and isolation valves are recommended so
that maintenance work can be performed without shutting off the air
supply.
4.1.1 Aftercooler/Separator –
Compressed air entering dryer must be cooled to a temperature of
140°F (60°C) or lower. Use of an aftercooler and condensate separator
may be necessary to reduce inlet air temperature to an acceptable
level.
NOTE: Installation of a refrigerated dryer ahead of a pressure-swing
desiccant dryer does not increase desiccant dryer capacity or reduce
purge ow requirements.
4.1.2 Receiver(s) –
Air receivers dampen pulsations from the compressor discharge line
and can eliminate some of the condensed moisture that is carried over
from the aftercooler and separator. They also provide a reservoir of
stored air for response to system demands in excess of compressor
capacity. Size and location of receivers in the compressed air system
need to be considered carefully. Flows must not exceed the adjusted
maximum inlet capacity of the desiccant air dryer.
4.1.3 Prelter(s) –
Adequate ltration is required upstream of the dryer in order to
protect the desiccant bed from contamination. The following ltration,
equipped with automatic condensate drains, is recommended:
• First Prelter - Particulate/Gross Liquid Removal - On heavily
contaminated systems, a gross contaminant lter to remove solids
and high inlet liquid concentrations should be used.
•Second Prefilter - Oil Aerosol Removal - On systems with
lubricated compressors, an oil removal filter to remove oil
aerosols and protect the desiccant beds from oil contamination
is required.
4.2 Physical Location
The dryer must be installed with suitable overhead protection
as well as clearance to change desiccant. Sufficient clearance
around the periphery of the dryer should be provided to allow
maintenance personnel access to all areas for routine inspections
and adjustments.
4.3 Minimum & Maximum Operating Conditions
The compressed air supply to the dryer inlet should be checked
periodically to ensure that dryer design specifications are not
exceeded. Normally the compressor installation includes intercoolers,
aftercoolers, separators, receivers, or similar equipment, which
adequately pretreat the compressed air supply in order to avoid
excessively high air temperatures and liquid slugging of downstream
equipment.
4.4 Maximum Operating Pressure (MOP):
•150 psig (10.3 barg) is standard.
•250 psig (17.2 barg) is optional.
Refer to Dryer Serial Number Tag.
WARNING - Do not operate the dryer at pressures above the
maximum operating pressure shown on the serial number tag.
NOTE: Consult factory for applications requiring higher maximum
operating pressures.
Compressor AftercoolerSeparator Receiver Prefilters Afterfilters ReceiverDesiccant Dryer
Figure 4-1
