Galvanic Applied Sciences 943-TGXeNA, Руководство по эксплуатации

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Revision 5 35 August 2021
3.2.3 Condenser Cooling Air Flow Adjust Valve
Sulfur vapour is always present in tail gas streams in sulfur recovery units. However, the
presence of this sulfur vapour inside the analyzer sample probe and sample handling system
is detrimental for two reasons. Firstly, sulfur vapour can interfere with the measurement of
both hydrogen sulfide and sulfur dioxide. Secondly, if sulfur vapour inside the sample probe
or sample handling system were to condense, it could lead to flow blockages inside the probe
or sample handling system. For this reason, the sample probe is designed to eliminate as
much sulfur vapour from entering the sample probe and sample handling system as possible.
This is accomplished using a ‘ cold finger ’ sample probe condenser at the probe tip that
condenses sulfur vapour inside the process pipe, as shown in Figure 16.
Figure 16: Sample Probe
Sulfur condensing on the probe’s ‘cold finger’ is hydrostatically returned to the process
stream and does not enter the sample probe. Air flow to the probe condenser is controlled
via a solenoid valve.
Actuation of the probe cooler solenoid is determined by either the temperature of
the incoming sample gas OR by the sulfur vapour content in the incoming sample
gas as measured by the analyzer. The control point for the probe cooler solenoid
is user configurable – refer to Section 5.4 for more details.
The Condenser Cooling Air Adjust Valve allows the user to control the flow rate of the
instrument air used to cool the condenser section of the sample probe.