Do you sometimes need to measure, draw or do something quickly? The speed at which you get to the result counts more than the perfect (scientific) approach. For this reason, we introduced a wink of knowledge. Science with a wink, so to speak. Our aim is not to prove anything scientifically, but to quickly demonstrate something pragmatically. If you’re interested, we would be happy to discuss these results in more detail with you and your project.

The density was measured with the DLO-M1 density sensor for liquids. For this purpose, the listed concentrations were passed through the sensor at a constant flow rate. Using the logging function, a reading for density and temperature was logged every second.

After a short time, the saturated brine also caused drifts in our sensor (Figure 2). This is, of course, not a satisfactory solution for continuous measurement. Due to the small measuring volume in our sensor, we came up with the right idea: we dilute the brine with pure water and then calculate back to get the total volume. The flow rate is measured or controlled with our own Coriolis sensors for the smallest flow rates. With a reduction in salinity of <15%, the initial drifts could be eliminated, allowing continuous measurement (Figure 3).

How can this now be implemented in practice? If the flow rate of the fresh water supply and the total volume at the outlet are measured, the concentration can be determined very accurately using a linear function (Figure 4). Due to the lower salt content, drifts also no longer occur, which enables long-term measurement in the field. The slight deviation in Figure 4 is due to the measurement setup. This allowed water to evaporate over the long measurement period (which is why the proportion of NaCl in the concentration increases).