Insights into the Application of Ultrasound Tomography in the Precipitation of Calcium Carbonate.

The application of an ultrasound tomography (UST) system in a liquid‐phase reactive crystallization process is reported. The measurement system was applied to precipitated calcium carbonate processing where liquid Na2CO3 was added to a CaCl2 solution. Analysis of the measured sound velocity signals from the experiments demonstrated a clear change in the average time‐of‐flight (TOF) delay signals, indicating the detection of the onset of the precipitation and the formation of the microcrystalline stable phase of calcite. Moreover, spatial‐centric TOF signals from the tomographic images were associated with an increase in the overall suspension density. These findings highlight the potential of the UST measurement system for studying the solidification phenomenon during CaCO3 precipitation. [ABSTRACT FROM AUTHOR]