Leading edge applications of s::can’s on-line uv-vis-spectrometers - Andreas Weingartner

5 years after market introduction, s::can´s "spectro::lysers" have not only proven in several hundred applications world wide their great accuracy, reliability and neglectable maintenance costs. Since 1999 they have also established in a wide variety of new applications, like for drinking water protection, for the control of complete wastewater treatment plants, at industrial applications like the control of paper mill or diary WWTPs, or in hydrocarbon alarm systems for the (petro)chemical industry.

Monitoring of NO3, TSS, and COD in an SBR reactor
Viennese scientists used a submersible UV/VIS spectrometer from s::can, Vienna, with an optical pathlength of 1 mm for the control of an SBR tank (Langergraber et al., 2004*). The instrument measured in-situ - directly in the reactor - and communicates the results in real-time to the PLC system. The auto-cleaning system which is operated by pressured air prevents trends from windows fouling over several months of operation.

There is no need for chemicals, membranes, pumps, filters, or wipers - nothing but 12 V low power energy and compressed air or water for the automatic cleaning. There are no moving parts - it is not even serviceable - and it is built to run at a max. rate of 4 meas. / minute, without ever leaving the water at almost zero operating costs.

In addition to nitrate nitrogen also TSS and CODsoluble were measured simultaneously with just one single instrument.

High correlation coefficients of R_ = 0.98 and 0.995 were obtained for NO3-N and TSS respectively by running an advanced local calibration. The measurement of NO3-N was possible for high TSS concentrations also.