Endress+Hauser SS1000, Hardware Installation And Maintenance Manual

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2-Pack Analyzer System
B
–
22 4900002256 rev. B 4-13-21
To replace the filter
If necessary, use the following steps to replace the filter:
1. Close the sample supply valve.
2. Unscrew the four screws with a 5/23 in. screwdriver from the base
of the filter. Remove the filter unit from the analyzer for disassembly.
3. Unscrew and remove the filter cap.
4. Remove the top O-ring.
5. Check if there are any contaminants or solid components blocking
the metal filter.
6. Drain any contaminants found and clean with isopropyl alcohol.
7. Replace the top O-ring.
8. Place the filter cap back into position and tighten.
9. Place the filter unit into the analyzer and tighten the base with the
four screws.
10. Check upstream of membrane for liquid contamination and clean
and dry out before opening the sample supply valve.
Servicing the H
2
S Scrubber
The H
2
S scrubber contains material that gradually loses its scrubbing ability
with use. The lifetime of the material depends on how much H
2
S flows through
the scrubber (gas composition) and how often (switching frequency). Thus,
scrubber lifetime is very application specific.
The SpectraSensors 2-pack analyzer system predicts the remaining scrubber
capacity by using the actual H
2
S concentration measurements and dry cycle
durations to calculate how much cumulative H
2
S has been removed by the
scrubber. Scrubber lifetimes have been simulated for typical natural gas and
fuel gas applications. As shown in Figure B–18 on page B–23 below, under
normal operating conditions, a 2 inch scrubber in a natural gas application with
an average H
2
S concentration of 4 ppmv will last for many years, whereas a 3
inch scrubber in a fuel gas application with an average H
2
S concentration of
100 ppmv would be expected to last approximately 190 days.
As an added precaution, a scrubber efficiency indicator, shown in Figure B–19
on page B–24 below, is mounted at the outlet of the scrubber.
Due to the chemical properties of the process samples, care must
be taken to repair or replace components with proper materials of
construction. Maintenance personnel should have a thorough
knowledge and understanding of the chemical characteristics of
the process before performing maintenance on the SCS.