A few months ago a density meter comparison test took place at a water reservoir of a hydroelectric power plant in France. The test was carried out by a contractor for a project of the biggest energy supplier of France. The goal of this comparative test was validating different density measuring methods for use in future projects of the end user.
The measuring instruments were evaluated during dredging operations for maintenance of the water reservoir. The water from this uphill basin is used by the French electricity company for power generation at their hydroelectric power plant downhill. The challenge of the contractor was to keep a certain water/solids balance during dredging to prevent accumulation of sediment in the flow from the power plant to the river. Also, wear caused by solids on the turbine of the power plant had to be prevented.
The contractor invited four suppliers of density meters to prove and validate their density measuring methods. These suppliers are using different technologies to determine the slurry density, done by the measurement of:
Radiation (Nuclear)
Acoustic impedance (Ultrasonic)
Electrical conductivity (Tomography)
Force and acceleration (Mass/volume)
One of the invited suppliers cancelled their participation for the test in advance, so three technologies were compared. The test was done during a period of four weeks in which the data of each measuring instrument were collected. The image below shows the configuration of the density meter comparison test.
After four weeks of evaluation, the ultrasonic density meter of Rhosonics was chosen as the winning technology. According to Rhosonics, this choice was based on the accuracy and stability of the measurements, but also on the easy installation and short calibration compared to the other density measurement technologies.
During the comparison test in France, the ultrasonic density meter of Rhosonics was contributing to:
- Prevention of plant shutdowns caused by sand accumulation in the flow from the uphill water reservoir to the river
- Prevention of wear on the power turbine of the hydroelectric power plant caused by the water/solids slurry
- Improvement of dredging efficiency
- No nuclear source, so no costs for licences, permits or specialized personnel
