Residence time distribution studies in rotating packed bed (RPB) reactor for improving its hydrodynamics and design validation using radiotracer

Rotating packed beds (RPBs) utilizes high centrifugal force to enhance mass transfer, making them ideal for intensified processes such as gas–liquid stripping, absorption, and reactive separations. This study investigates the liquid-phase hydrodynamics of two reactor designs of RPB i.e. base and modified—using radiotracer-based residence time distribution (RTD) measurements. Technetium-99m was used as a radiotracer to measure RTD under varying liquid flow rates, gas flow rates, and rotational speeds. The base design exhibited significant flow path malfunctions, particularly under gas flow, leading to reduced process efficiency and degradation of packing material. In contrast, the modified RPB design eliminated flow path malfunctions by improving design of liquid distributor. Two different combination of plug flow and tank in series model were used to simulate RTD curves. The present study provides experimental data and validated models for the design validation and scale-up of intensified processes using RPB reactors.