Control of a Spinning Disc Reactor: An Experimental Study

Despite abundant experimental work on intensification aspects of spinning disc reactors (SDRs), research on control characteristics of such novel devices are rather scarce. Control of SDRs may be challenging due to fast dynamics and high responsiveness of the system. However, the readily controllable rotational speed of the disc may offer an extra degree of freedom in control system design. In the present work, two test processes, namely, neutralization of HCI and NaOH and precipitation of barium sulfate, are chosen to investigate the control aspects of SDRs experimentally. The most commonly used controllers based on PI/PID algorithms implemented in LabVIEW, coupled with commercially available instrumentation, are employed to achieve the control objectives. The pH control of the neutralization process was successfully achieved using a PID controller which manipulated the flow rate of the base stream to the SDR. Addition of a disturbance observer scheme resulted in further enhancement of the control performance by suppressing the undesired effects of pH system nonlinearity. The conductivity control of the precipitation process was successfully achieved by manipulating the disc rotational speed, which presents a vastly appealing potential for adopting an innovative approach to process control for SDRs.