Galvanic Applied Sciences 943-TGS, Руководство по эксплуатации

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Revision 1 45 6/27/2017
a)
Plant Factor
- This parameter specifies the
Plant Factor
term used in the analyzer’s
calculation of Air Demand. The Plant Factor is a gain term applied to the air demand
output used to adapt the process variable (Air Demand) to the plant’s front end air
adjustment capability.
Plant Factor
is defined as follows:
pf = -Q
tg
(100) / ([H
2
S]
ag
) (Q
ag
)
where:
Q
tg
= flow rate of the tail gas stream in moles/unit time (typical)
Q
ag
= flow rate of the acid gas feed stream in moles/unit time (typical)
[H
2
S]
ag
= molar concentration of H
2
S in the acid gas feed stream (typical)
PF =
plant factor
The value for Plant Factor is typically in the order of -3.0.
b)
Operating Ratio
- Under stoichiometric concentrations of H
2
S and SO
2
([H
2
S] / [SO
2
] =
2/1) the Air Demand output becomes zero regardless of the plant specific gain factor (F)
when the operating ratio (R
op
) is two (2). When the plant specific gain factor (F) is
established for a particular process, the units of Air Demand become ‘percent change
required in process air’. (
i.e.,
a computed Air Demand of +1.5% means that the process
is 1.5% excess in air.) To achieve optimum performance of the Claus Sulfur Recovery
Plant, the Air Demand should be kept near zero.
c)
H2S Span
- This parameter specifies the span factor utilized for the H
2
S concentration
display and output. This value should always be close to 1.0.
Any deviation of the H2S span parameter will impact the output calibration
of the analyzer.
d) SO
2
Span - This parameter specifies the span factor utilized for the SO
2
concentration
display and output. This value should always be close to 1.0.
Any deviation of the SO2 span parameter will impact the output calibration
of the analyzer .
e)
COS Span
- This parameter specifies the span factor utilized for the COS concentration
display and output. This parameter (when used) should always be close to 1.0.
f)
SVAP Span
- This parameter specifies the span factor utilized for the SVap
concentration. This parameter (when used) should always be close to 1.0.
g) CS2 Span - This parameter specifies the span factor utilized for the CS2 concentration.
This parameter (when used) should always be close to 1.0.
h) Cell Length - Indicates the cell length of the measuring cell. This value is used in the
calculation of the gas concentrations.
i)
Fixed Temperature
- To select
Fixed Temperature,
click on the
Fixed Temperature on/off
field using the Field Next button on the keypad. Use the Enter key to toggle the x on and
off in this field. If the x is present, the analyzer will use the temperature indicated here