An Ultrasound Tomography Method for Monitoring CO2 Capture Process Involving Stirring and CaCO3 Precipitation

Abstract

In this work, an ultrasound computed tomography (USCT) system was employed to investigate the fast-kinetic reactive crystallization process of calcium carbonate. USCT measurements and reconstruction provided key insights into the bulk particle distribution inside the stirred tank reactor and could be used to estimate the settling rate and settling time of the particles. To establish the utility of the USCT system for dynamical crystallization processes, first, the experimental imaging tasks were carried out with the stirred solid beads, as well as the feeding and stirring of the CaCO3 crystals. The feeding region, the mixing process, and the particles settling time could be detected from USCT data. Reactive crystallization experiments for CO2 capture were then conducted. Moreover, there was further potential for quantitative characterization of the suspension density in this process. USCT-based reconstructions were investigated for several experimental scenarios and operating conditions. This study demonstrates a real-time monitoring and fault detection application of USCT for reactive crystallization processes. As a robust noninvasive and nonintrusive tool, real-time signal analysis and reconstruction can be beneficial in the development of monitoring and control systems with real-world applications for crystallization processes. A diverse range of experimental studies shown here demonstrate the versatility of the USCT system in process application, hoping to unlock the commercial and industrial utility of the USCT devices.

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

“…The employed UST is based on a transmission approach with an excitation frequency of 400 kHz, consisting of a single array of 16 piezoelectric transducers. The aluminum-made transducers (diameter 10 mm) were mounted at the outer section of the reactor and acted as both a transmitter and a receiver [24]. The existence of microcrystalline particles has the potential to scatter and absorb sound waves, causing alterations in both the amplitude and velocity of the waves as they propagate through the suspension.…”

A 4-D Ultrasound Tomography for Industrial Process Reactors Investigation

“…The developed UST system has been described priorly in [32]. The hardware design provides 84 measurement channels for possible use.…”

A Fast Electrical Resistivity-Based Algorithm to Measure and Visualize Two-Phase Swirling Flows

“…Based on the sensor design and electrode placements, the tomograms can give two (cross-sectional) or three-dimensional (reconstruction of a volume) information. Different operating principles are the basis for tomographic applications: electrical [14], microwave [15], ultrasound [16], gamma rays [17], and x-rays [18] are popular in a variety of research and industrial applications.…”