Installation; Location In The Compressed Air System; Prefilter; Aftercooler/Separator - Gardner Denver DGH Series Instruction Manual

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 insufficient 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)
Compressor
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 flow 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.
Aftercooler Separator Receiver
4.1.3 Prefilter(s) –
Adequate filtration is required upstream of the dryer in order to
protect the desiccant bed from contamination. The following
filtration, equipped with automatic condensate drains, is
recommended:
•
First Prefilter - Particulate/Gross Liquid Removal - On
heavily contaminated systems, a gross contaminant filter
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.
Prefilters Desiccant Dryer
Figure 4-1
4.1.4 Heatless Pressure-Swing Desiccant Air Dryer
4.1.5 Afterfilter(s) –
To ensure downstream air purity (prevent desiccant dust from
traveling downstream) adequate filtration downstream of the
dryer is required.
•
First Afterfilter - Particulate Removal -Typically 1-micron
filtration is specified although finer filtration is available.
•
Second Afterfilter - Oil Vapor Adsorption -This filter 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.
4.2 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.
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4. Installation
Afterfilters Receiver
4. Installation