Principle Of Operation - AADCO 737 Series Operating Instructions Manual

5.0 PRINCIPLE OF OPERATION (REFERENCE FIGURE 17).
5.1 The 737-series pure air generators produce absolutely clean air from
pressurized unclean air by chromatographic techniques. Pressurized air from a
compressor or other source enters the number one or number two column
system, depending upon the status of the solenoid valve located at the inlet of
the column. These valves (S-1 and S-2) are normally closed so that when the
POWER switch is off the inlets to the columns are closed, sealing the system
against possible contamination.
5.2 The pressurized air passes through the column where selective adsorption
takes place, with a subsequent separation of the various components present
in the air. Only the desired components, which elute first, are permitted to
reach the end of the column system and elute, whereupon the solenoid valve at
the head of the separation column closes and the solenoid valve at the inlet to
the alternate column systems opens.
5.3 Pressurized unclean air now enters the alternate column system where
separation again takes place.
produces a steady flow of purified air.
5.4 During the interval that pressurized unclean air is being separated in one
column, a portion of the clean air passes through the purge valve and
backflushes the alternate column of impurities. This purge valve, Figures 5 and
6 (19), has been set at the factory for optimum flow and MUST NOT BE
ALTERED.
5.5 The backflush flow of air with impurities exits from the instrument through the
swage bulkhead connector labeled DUMP at the rear of the instrument, Figure
1 (60). THIS EXIT MUST NOT BE RESTRICTED. A back pressure situation
must be avoided at this fitting.
5.6 The timer, which provides alternate power to the solenoid valves, has been set
to effect the proper residence time of the unclean air in the columns and also
the purge time for each size reactor.
5.7 To prolong the life of the support media within the columns, it is mandatory that
the operational directions for the instrument be followed as closely as possible.
Selection of this separation media, residence time in the column, proper input
pressures, purge flows, and column volumes have been determined to meet
the requirements of the particular 737-series pure air generator being used.
These components are NOT interchangeable except among units of the same
rated output.
The alternation of the two column systems
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