Genomljusning – Optical sensors: the incoming future for process optimization in drinking water treatment plants

The project Genomljusning started in 2017 and ended in 2020. 

Results

The results from the project are described in the final report ”Optiska sensorer inom dricksvattenberedning. Erfarenheter från SVU-projektet Genomljusning” which was published by Svenskt vatten. The report is witten in Swedish, with an English summary.

SLU news:

• How can we ensure an efficient production of drinking water of good quality? (news about the thesis of Claudia Cascone)
• Improve the cleaning of drinking water with optical sensors in more waterworks (news about the final report from the Genomljusning project)

Publications:

• Cascone, Cl. 2021. Optical sensors in drinking water production : Towards automated process control in relation to natural organic matter. Acta Universitatis Agriculturae Sueciae, 2021:17. Sveriges lantbruksuniv.
• Cascone, C., Murphy, K. R., Markensten, H. , Kern, J. S. , Schleich, C. , Keucken, A. and Köhler, S. J. 2022. AbspectroscoPY, a Python toolbox for absorbance-based sensor data in water quality monitoring, Environ. Sci.: Water Res. Technol., 2022, 8, 836-848 
• Köhler S.J., Cascone C. och Murphy K. (2021). Optiska sensorer inom dricksvattenberedning. Erfarenheter från SVU-projektet Genomljusning. SVU-rapport 2021-25. Stockholm, Svenskt Vatten.

About the project

In Sweden an increasing trend of natural organic matter (NOM) in surface water has been observed, which may cause problems for the production of drinking water. High concentration of NOM can affect the taste and odor of the produced water, growth of bacteria, viruses and parasites, as well as the formation of carcinogenic disinfection byproducts (DBPs).

NOM fluctuations in raw water and process water follow natural mixing in lakes and storm or snow melting events in running water. During these periods of the year, the drinking water plants can be faced with operational problems. NOM fluctuations can be easily followed using optical sensors, together with physico-chemical sensors. However, they are used only in a few, mostly larger, waterworks in Sweden.

Our research aimed to:

• achieve a good and steady process water quality using sensors with respect to color and NOM concentration and composition in different types of raw water;
• reduce the use of precipitation chemicals and thus sludge production through optimized dosage;
• optimize the operation of active carbon filters, membranes and managed aquifer recharge;
• establish quality insured measurements and evaluation procedures using in situ sensors.

The project was financed by SLU, the Swedish water and waste water association, DRICKS, SafeDrink, DigiDrick and a cooperation of eight utilities in Sweden (Borås Energi och Miljö, Gästrike Vatten, Göteborg Kretslopp och Vatten, Norrvatten, Sydvatten, Tekniska Verken, Uppsala Vatten, VIVAB). The project was run in cooperation with Kathleen Murphy at Chalmers University, Göteborg.