Hydrodynamics behavior in quadrilateral bubble column using industrial radiotracer techniques

Radiotracer technique is well established assisting tools for troubleshooting and process optimization in process industries. Industrial radiotracer has proved to be a very useful tool to examine and improve the design of pilot-scale systems. However, to date, no detailed large-scale studies have been performed to investigate the capability of nanoparticle radiotracers in any pilot plant or laboratory scale vessels. Thus, the performances of the nanoparticle radiotracer for industrial application purposes are being questioned. This study has demonstrated the entire design development process of a bubble column reactor test rig for investigating hydrodynamics behaviour using industrial radiotracer techniques with aid of complete system. The influence of superficial gas velocity and sparger design on gas hold up in bubble column has been successfully studied. Therefore, the hydrodynamic parameters of the bubble column reactor are validated using the conventional method with the aid of high-speed camera technology. The results indicate that the higher sparger opening area contributed to higher gas holdup up to 50% from initial water level and increased the value superficial gas velocity which resulting increasing Reynolds number value. From the qualitative observation analysis and Reynolds number information, the flow regimes for bubble column reactor are determined from homogeneous to heterogeneous flow successfully. The solid nano-sized particle radiotracer 198Au@SiO2 has been synthezised and characterized for tracing liquid phase effectively. The performance of newly synthesized industrial radiotracers was successfully validated by investigating aqueous phase system in bubble column reactor at different air flow rates and sparger design using radiotracer flow measurement method and residence time distribution studies with accuracy more than 98%. The results of flow measurement show that the experimental volumetric flow rate is in good agreement with conventional flow meter value. Moreover, residence time ii distribution results indicate that the bubble column reactor was fit with perfect mixers in series with exchange model (PMSE) from the RTD mathematical simulation. Both techniques have validated the synthesized industrial nanoparticle radiotracer 198Au@SiO2 performance in tracing liquid phase effectively as a comparison with conventional radiotracer 99mTc. Whereas, the study has managed to measure and simulate particle calibration map and verify position reconstruction algorithm for radioactive particle tracking technique using MCNPX code. The method was successfully applied to model the motion and simulated spiral trajectory of the single particle radioactive tracer 198Au and 46Sc. The simulation results have successfully reconstructed 26,000 tracer particle histories map to be used for particle tracking in bubble column reactor. The radioactive particle tracking facility and encapsulated tracer particle has been designed and developed. The hydrodynamic behaviour investigation in bubble column reactor is carried out using simple radioactive particle tracking experiments. Finally, by introducing alternative non-destructive, non-invasive, and effective radioisotope techniques for understanding hydrodynamics behaviour of multiphase systems, it offers a high potential for the niche of industrial applications towards future commercialization of process diagnostics and troubleshooting services in Malaysia