The Sensitivity of Predicted Solar Thermal Reactor Performance to Solid-state Kinetics
A solar thermal rotary kiln reactor designed to continuously decompose Co3O4 to CoO was analyzed numerically using the finite-volume technique. The reactor model calculates the reactor temperature, the extent to which Co3O4 is converted to CoO, and the efficiency with which concentrated solar energy is used to drive the reaction as a function of the feed rate of Co3O4 and the solar power. In this study, we analyzed the sensitivity of the reactor model to the solid state kinetic model selected for the decomposition reaction. Two competing solid state kinetic models from the literature were considered. The first, called the shrinking core model, was developed at Valparaiso University and the second, the Avrami-Erofeyev model, was developed at the Georgia Institute of Technology. The results show that the reactor model is extremely sensitive to the kinetic model selected. For example, at a Co3O4 feed rate of 90 g/min and a solar power level of 4000 W, the reactor model predicts that 100% of the Co3O4 is converted to CoO at an efficiency of 30.0.% when the shrinking core model is selected for the reaction kinetics and that none of the Co3O4 is converted to CoO when the Avami-Erofeyev model is selected. Given the sensitivity of the predicted reactor performance to the reaction kinetic model, future research is needed to determine why the available kinetic models are different and on developing a more robust model suitable for use in reactor modeling efforts.
Jaacks, Amanda and Venstrom, Luke, "The Sensitivity of Predicted Solar Thermal Reactor Performance to Solid-state Kinetics" (2018). Symposium on Undergraduate Research and Creative Expression (SOURCE). 737.