In December last year, the first prototypes of the imec liquid sensors were installed at four test locations in the provinces of Antwerp and West Flanders. In the coming period, new test sites will be set up across the region of Flanders. These imec sensors will measure electrical conductivity, temperature and acidity (pH) in surface water and wastewater.

Comparative tests
The aim of the field tests is to know how the imec sensors – which have already proven their reliability in laboratory conditions (LINK) – behave in real world conditions. The results will be used to further develop the sensors and to achieve reliable measurement results in diverse outside conditions.

In order to evaluate the IoW sensor data, more expensive multi-parameter reference sensors of the Flemish Environment Agency (VMM) are installed at the test locations. In this way, the measurement results of both sensors can be compared and evaluated.

At three of the test locations sensors measure surface water. One location concerns sewage water near a sewage treatment plant.

Robust sensors with consistent results
The aim is to fully equip six more test sites with both reference sensors and imec sensors in the coming weeks and months.
The biggest challenges are to guarantee reliable measurements by preventing so-called ‘biofouling’ (damage to the sensor due to biofilm formation), but also other types of pollution and the accumulation of unwanted material in the vicinity of the sensor that can affect its functioning.

The researchers also want to discover how the sensors react to a wide variety of water types. The resistance of the sensors under various field conditions (e.g. variations in water pressure) and the robustness of the connectors and other technical equipment are under examination.

The ultimate goal of the field tests is to obtain a consistent real-time data transfer to the IoT structure.