Madur Sensonic 4000, Руководство пользователя

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BASIC PRINCIPLES OF CALCULATING RESULTS Sensonic 4000
7 BASIC PRINCIPLES OF CALCULATING RESULTS
7.1 Quantities obtained from direct measurements (O2, CO, NO, SO2)
In direct measurements the temperature values and also the concentration of those gas elements which are
detected by independent electrochemical sensors are obtained. The electrochemical cell indications are
proportional to the volume concentration of the detected elements expressed in [ppm] (parts per million).
The following quantities are obtained by means of direct measurement:
### flue gas temperature T gas and ambient temperature, expressed in [oC]
### volume concentration of CO [ppm]
### volume concentration of NO [ppm]
### volume concentration of SO2 (or any other optional cell) [ppm]
### volume concentration of O2 [%]
7.2 Calculating the concentration of carbon dioxide
The volume concentration of carbon dioxide (expressed in [% vol]) is not obtained by direct measurement,
but is calculated on the basis of measured oxygen concentration and the CO2max parameter, characteristic
for the given fuel.
Formula 1 shows the formula according to which the analyser calculates volume concentration of CO2:

 
CO = CO
2 2max
 






1
20 95%
2
O
meas
%
.
7.3 Calculating the concentration of nitrogen oxides NOx
In addition to nitric oxide NO, combustion gases contain also higher oxides of nitrogen (mainly NO
2
)
Sensonic 4000 does not have the nitrogen dioxide sensor in its basic version, only the nitric oxide sensor
NO. But it is possible to calculate the NO2 contents on the basis of the measured NO. It is generally
assumed that nitric oxide NO contained in combustion gases makes up about 95% of the total amount of
nitrogen oxides NOx.
Sensonic 4000 calculates the total concentration of nitrogen oxides NOx according to
the following formula:

 
 
NO
X
ppm
NO ppm

0 95 .
If the optional sensor of the Sensonic 4000 analyser is the NO2 sensor there is no need to calculate the
amount of NO2. Then the NOx concentration is calculated by the analyser as a simple sum of measured NO
and NO2 concentrations.

     
NO NO ppm NO
X 2
ppm ppm
 
7.4 Concentration of "undiluted" carbon monoxide COundil
To make the calculation of the carbon monoxide concentration in combustion gases independent of excess
air with which the combustion process is conducted, the idea of "undiluted" carbon monoxide COundil was
introduced (it is also called the CO concentration calculated for 0% O2 ). The value of COundil is calculated
according to the formula below:

CO = CO
undil
 
where:
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