Weiterentwicklung und Charakterisierung eines Spinning‐Disc‐Reaktors nach dem Rotor‐Stator‐Prinzip

Abstract

Ein vielversprechendes Reaktorkonzept zur Prozessintensivierung stellt der Spinning-Disc-Reaktor (SDR) dar. Im Rahmen dieser Arbeit wurde der Reaktor zu einem SDR nach dem Rotor-Stator-Prinzip weiterentwickelt, wobei die rotierende Scheibe von einem zylindrischen Stator umgeben ist. Zum besseren Verständnis der Vorgänge in dem dünnen, stark gescherten Flüssigkeitsfilm wird die Mikrovermischung mithilfe der Villermaux-Dushman-Reaktion untersucht. Darüber hinaus erfolgt eine systematische Untersuchung der Einflussparameter auf die Stoffübergangsvorgänge bei der heterogen katalysierten Glucose-Oxidation. Hierzu wird ein Pt/C-Katalysator auf der Scheibe immobilisiert. Further Development and Characterization of a Rotor-Stator Spinning Disc ReactorThe spinning disc reactor (SDR) is a promising reactor concept for process intensification. For this work, the reactor is modified into a rotor-stator SDR by placing the disc in a cylindrical shroud. The Villermaux-Dushman reaction is applied to investigate the effect of high shear forces on mixing efficiency of liquid flow in the narrow reactor cavity. Subsequently, this allows the methodical examination of mass transfer properties for heterogeneously catalyzed reactions. The glucose oxidation with dissolved oxygen in water is studied as model reaction employing a Pt/C catalyst immobilized on the rotating disc.

Micromixing in a Rotor–Stator Spinning Disc Reactor

“…The reported micromixing times are of the order of milliseconds. Later in 2015, Haseidl et al studied the performance of an rs-SDR, 9 and their results indicate that better mixing is achieved at higher rotational speeds, and by injecting the limiting reactant at a radial position far from the center of the disc.…”

Rotor‐Stator Spinning Disc Reactor: Characterization of the Single‐Phase Stator‐Side Heat Transfer

“…An increase in the stator-side Nusselt number with higher Prandtl and Reynolds numbers and higher dimensionless throughputs was observed for both regarded setups, while the Nusselt numbers for the aspect ratio G = 0.0154 are higher compared to the setup with G = 0.0074, which can be explained by the respective heat transfer area. Laminar and turbulent flow regimes with regard to the rotational Reynolds number are found for both setups, with the critical Reynolds numbers being Re w,krit,G=0.0154 = 10 5 and Re w,krit,G=0.0074 = 10 6 . In the laminar regime, the heat transfer is domi- For an open cavity, a Nusselt correlation for the stator is given for the turbulent regime [29].…”

“…The distance between the rotating and static parts is a few millimeters, whereas the rotor radius ranges between 0.06 and 0.14 m. Due to the high rotational disc speeds of the rotor, which reach about 4000 min −1 , and the small gap height, high shear forces are induced in the fluid within the gap. In dependence of the throughput through the gap, the rotational disc speed and the aspect ratio G , turbulences and the formation of different flow regimes are caused , . This in turn influences the heat and mass transfer properties of the rotor‐stator reactor.…”

Single‐Phase Flow Residence‐Time Distributions in a Rotor‐Stator Spinning Disc Reactor

“… Schematic depiction of the axial profiles of radial velocities in a rotor‐stator cavity in the regime of torsional Couette flow without (a) and with superposed throughflow (b) 12, 16, 23. …”

“…Owing to the velocity differences, large shear forces are introduced into the fluid in the gap. This leads to rapid turbulent mixing, large gas‐liquid, liquid‐liquid, and liquid‐solid mass transfer, and high heat‐transfer coefficients in the reactor 8–12.…”