HS 55 (Batch Mode)
Function and design
17
3.2.4
Hg Plus Upgrade Modul (optional)
The optional module is located in a compartment at the top of the Hg/hydride system.
You can open the red cover of the Hg/hydride system and access the module.
The module consists of the following components:
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quartz tube with the gold collector
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infrared sensor
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fan
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3/2-way solenoid valve (at the inlet)
The solenoid valve switches the following gas flows to the gold collector:
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reaction gas for loading the gold collector
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direct gas flow for expelling the enriched mercury
The gold collector is the core of the module. It contains a loosely rolled-up gold/plat-
inum mesh which is approx. 20 mm wide. The mesh is secured in the quartz tube.
The gold collector enriches the mercury from the reaction gas on its surface by means of
amalgamation. Mercury is only released again from the gold collector when heated to a
temperature of approx. 630 °C during bake-out.
The quartz tube is surrounded by a heating coil. The heating coil supplies heat to the
gold collector from the outside during bake-out. An infrared sensor monitors the tem-
perature. After bake-out, the axial fan cools the quartz tube with air. This way, the Hg/
hydride system prepares the gold collector for the next measurement.
Figure 5 Gold collector
1 Gas inlet
2 Heating wire
3 Gas outlet
4 Heating connection
5 Infrared sensor
6 Heating connection