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Pure Air Generators:
The AADCO 737-series
Pure Air Generators have gained universal acceptance as the
instruments of choice where there is a requirement for a reliable,
absolute source of zero air. Hundreds of these units are now
distributed throughout the world, providing zero air for calibration
purposes or relieving users from the tedious problems associated
with stored air cylinders. Users include most federal and state air
monitoring boards, foreign air monitoring networks, many federal
analytical laboratories and a considerable number of industrial
laboratories. Their ruggedness and compactness permit their use for
in-plant process applications as well. In addition to serving as a
source for zero air they provide clean, dry air for valving,
solenoids and other process equipment. The life span of process
instrumentation is greatly prolonged and maintenance is minimized
through use of clean, dry air.
OUTPUT PURITY
The air product from the 737-series Pure Air Generators will
easily satisfy the most demanding requirement for purity. AADCO's
purity specifications: < 1 ppb ozone, methane, hydrocarbons, NO/NOx,
H2S, S02, COS, CO, CO2, SF6 and fluorocarbons. All particulates are
removed from the source air and never appear in the air product. It
is typical for air monitoring equipment, calibrated to zero with
cylinder air which is labeled as zero air, to indicate a greater
deflection through zero when connected to a 737-series Pure Air
Generator, clearly demonstrating the greater purity over cylinder
air. In addition, the dewpoint of the air product from any
737-series Pure Air Generator will not exceed -60 F, making this the
ideal air source. Equally important, the oxygen concentration is a
constant 21%, as found in the ambient environment. This, again, is
in contrast with zero air cylinders where a 6-8% variation in the
oxygen concentration is not unusual. This variation has a profound
effect when calibration of ozone generators and ozone monitors or
total hydrocarbon analyzers is attempted. This oxygen variation
effect becomes even more pronounced when multiple instruments and
locations are involved.
CONSISTENT ZERO
AIR
The specified purity described above remains absolutely constant
from day-to-day, month-to-month and year-to- year. This consistent
purity is available from one AADCO pure air generator to the next,
anywhere in the world, assuring more positive collaboration between
widely separated laboratories which had previously depended upon
locally obtained cylinders of zero air. The stable, reproducible
output permits precise zero calibration of all ambient air monitoring instruments, regardless of location. It also allows those
researchers pursuing environmental impact studies to reliably
determine the natural ambient background of any environment.
Analysts concerned with the analysis of air from environmental
chambers, ambient air, the contents of air cylinders, physiological
respirations, etc. are now able to practice vacancy chromatography,
differential response chromatography or direct analysis by using the
pure air generator output as reference air. Laboratory use of a pure
air generator, such as using air as an aid for such activities as
evaporation, concentration and derivitization, can avoid side
reactions and sample contamination with pure, dry air instead of air
from questionable sources such as air cylinders or laboratory
stopcocks.
SAFE ELIMINATION
OF AIR CYLINDERS
In addition
to generating consistently clean air, the AADCO pure air generators
have effectively eliminated air cylinders and their associated
regulators from a great number of laboratories. They now offer an
element of safety and convenience for laboratory personnel which has
been unavailable until now. All of the inconveniences associated
with air cylinders are eliminated the handling of bulky cylinders,
mismatched regulators, storage of unused cylinders and the possible
mislabeling of FULL and EMPTY, causing uncertainty over residual
volume and pressure, demurrage, leaks, dangers of explosions,
unavailability of air at critical times due to either poor cylinder
deliveries, ordering delays, etc. With floor space at a premium in
most laboratories, use of a pure air generator frees that space
normally occupied by air cylinders and clean air is always
available. These generators are also found in mobile laboratories
and remote monitoring stations where zero air is required but
cylinder deliveries and changeouts are difficult logistical
problems. Some of the
AADCO high output units have found application as dry spec, etc.
Those applications and techniques which involve
Inordinate consumption of quality air, such as atomic absorption,
some high pressure liquid chromatography
Instruments and flame
photometers are best served by pure air generators. These units have
proven to be more convenient and economical over the battery of air
cylinders which are required to sustain these operations.
COMPLETELY
SELF-CONTAINED
All AADCO 737-series Pure Air Generators are completely
self-contained units, with their own oil-less air compressors and
unique contaminant removal systems. They are offered in a range of
output volumes from 1-Liter/minute to 100 Liters/minute. The small,
1-Liter/minute unit is completely self-contained within one cabinet,
including compressor. Its compactness, less than two cubic feet, and
light weight, less than thirty pounds, permit easy portability from
one work area to another. Bench space requirements are minimal—12
inches wide by 18 inches deep. All connections are made externally
to the unit and start-up is accomplished in less than 5 minutes.
Every 737-Series Pure Air Generator contains a purification reactor,
input and output pressure gauges for ease in monitoring the
condition of the compressor systems and
establishing output pressure for the receiving equipment, 9-inch
rotameter calibrated for the full range of output for
each pure air generator,
completely variable output flow adjust valve and output pressure
regulator. No pressure regulator systems need be supplied by the
user. Output flow and output pressure are constant without the use
of ballast tanks.
MODELS AVAILABLE
AADCO offers a variety of models from which selection is made
depending upon application, output volume and
mounting requirements. Mounting options include either bench
mounting or rack-mounting for all units, regardless
of output volume. For
those instruments producing volumes greater than 0-Liters/ minute,
larger components are entailed which necessitate a larger
housing.
BENCH TOP UNITS
Aadco
manufactures units that house components capable of output volumes
of 0-50 and 0-100 liters/minute; 0-20 and 0-30 Liters/minute and
0-1, 0-5 and 0-10 Liters/ minute respectively. We manufacture the
full family of bench-mounted pure air generators whose output
volumes are described above. Dimensions of the instruments are:
21"H x 17'/2"W x 25"D; 15"H x 17Y2"W x
21"D; 15"H x 17Y2"W x 18D, respectively. All units
contain a purification reactor, input and output pressure gauges,
9-inch rotameter, output flow adjust valve—all components sized to
the output flow requirements of the particular instrument. All of
these instruments function exactly alike, differing only in power
requirements, component sizing and cabinet dimensions.
The 737-12
bench-mounted Pure Air Generator system, with maximum output volume
of 0-30 Liters/min. @ 0-50 psi, is available complete with
compressor. The upper unit contains the purification system, with
methane reactor and heat status indicator systems. A cycling heat
indicator lamp gives assurance of temperature maintenance of the
methane reactor at its preset operating temperature. Should the
indicator lamp be suspect, front panel test jacks permit monitoring
with a VOM for further verification of heat status. All fuses are
front panel mounted for rapid and easy accessibility- All electrical
controls are also located on the generator front panel, including
the power switch to the compressor, even though the compressor is
located in a separate unit. Electrical connection between the two
units is made through a twist-lock umbilical which can also be
connected to any AC outlet without special adapters.
The lower unit houses
the compressor, mounted on a special vibration-isolation support.
High volume cooling fans sustain a compatible internal temperature
for optimum operation. Air enters through a strategically placed
opening in the top of the unit, passes through a baffle system to
eliminate sound from the unit, across the compressor and out through
several openings located on the rear floor of the unit. Should there
be a failure of the air circulating fans, an automatic thermal
switch cuts off electrical power to the compressor, avoiding
overheating and possible damage. This same thermal safety is
incorporated in all compressors which AADCO supplies with pure air
systems or as replacements. The complete interior of the unit is
covered with high density sound absorptive insulating material,
including the baffle system. Placement of the generator and
compressor units may be side-by-side or one above the other, as
shown. The high temperature connecting air hose which runs between
the
two units is of
sufficient length to permit either configuration.
RACK MOUNTED
UNITS
This
purification unit is mounted immediately above the compressor unit,
for all systems other than the 737 R-1 pure air generator. This one
particular generator system, which has a maximum output volume of
1-Liter/minute, contains within a single cabinet both the compressor
and purification systems, as with the 737-1 bench-mounted unit. All
other rack-mounted systems require separate cabinets for the
purification and compressor sections. The same attention to detail
is paid to selection of components for the rack-mounted systems as
with the bench-mounted units. Heat indicator lamp, test jacks and
front panel fuses are also standard with these units affording ease
of service and component accessibility to the
operator. The rack-mounted compressor units sustain the same baffle
system and high volume cooling as described for the
bench-mounted systems. The same safety features prevail, including
the thermal safety switch for the compressor in
the event of failure of
the cooling system. Soundproofing is also an available option, as
are slides, selected for weight capacity, with extenders to fit any
size cabinet. All front panels are a full 19-inches, with mounting
slots.
Output volumes for these
rack-mounted units range from 1-Liter/minute to 30-Liters/minute.
Purchases may be made to include or exclude compressor or silencer
housing. Consult the price list or the factory for full listing.
Factory technical recommendations for applicability or appropriate
size considerations is especially suggested, particularly for
those who are considering their first system in order to ensure
purchase of systems which will satisfy all of the
requirements of
the user.
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