S Q I
GO Systemelektronik GmbH Faluner Weg 1 24109 Kiel Germany Tel.: +49 431 58080-0
Fax: -58080-11
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In Figure 1 below we show results of measurements in the supply of a wastewater treatment plant. The red
lines show the concentration gradient of the COD measurements. The green line visualizes the characteristics
of the corresponding SQI values for this COD measurement. The given scales are shown on the left and right
side of the application. High values of the SQI correspond with extreme changes in the value of the COD.
Figure 1
∗
Concentration gradient of COD measurements (red) with the SQI (green)
Between the 12th and 16th of November a contamination could be determined, which was ascribed to a faulty
compressor. By the use of the SQI the failure of the cleaning was detected very quickly and could be fixed
without causing major damage. In October there was a brief single event – without recognized influences in
the COD. At the end of the year, the water matrix varied due to strong temperature changes and caused a de-
terioration of the SQI values without leaving the acceptable range.
Figure 2
∗
Absorbance spectra of the COD calibration
The function of the SQI as proof of quality
and indication of malfunctions is easy to
recognize in the Figure 1. The good per-
formance of the SQI can also be ascribed
to the high-quality calibration created by
54 reference values, taken over six month.
The absorbance spectra of this calibration
are shown in Figure 2.
For further information please contact GO Systemelektronik.
∗
The Graphic is generated with Spectrum Visual.
green line
red line
