The classical disinfection of drinking water using chlorine has some major disadvantages. If organic acids are present, cancerogenous Trihalomethanes can be formed. Also, residual traces of chlorine in the final water can leave an unpleasant taste. One of the alternatives is to use chlorine dioxide because it doesn’t show the negative effects as mentioned. In addition, it gives much better disinfection efficiency. Chlorine Dioxide is generated directly on site immediately before use. The exact measurement and control of the reactor is crucial. The typical concentration range for optimal dosing is at around 0.2g/l. Chlorine dioxide measurement can be done reliably and selectively using an inline absorbance measuring technique at 436 nm.
The absorptiometer ColorPlus from SIGRIST is providing a problem specific solution for chlorine dioxide measurement. In a special, corrosion resistant flow cell made from PVDF, the Chlorine Dioxide concentration is measured at a wavelength of 436 nm. At the same time, the absorption is measured at 546 nm to compensate for any existing turbidity. The applied dual-beam method results in a high stability and reliability of the measurement. One of the first customers has been Evides in Rotterdam, who purchased 40 units for the modernisation of their water treatment facilities.
Products: ColorPlus in-line