THERMAL PERFORMANCE AND CONTROL OF A SOLA R-DRIVEN CATALYTIC REACTOR

The decomposition of sulfur trioxide is an important endothermic react ion in many thermochemical prooesses for the production of hydrogen fr om water. A solar central-cavity receiver enclosing a tubular catalyti c reactor is a potential heat source for this reaction. This paper pre sents an analysis of the thermal performance of the reactor in the ste ady state and in response to changes in energy input to the receiver a nd flow of sulfur trioxide. The mathematical model includes heat trans fer from the cavity and the packed-bed tubular reactor coupled to heat transfer and reaction kinetics in the axial and radial directions in the packed bed. The results of the mathematical analysis are compared with experimental data obtained by GA Technologies from a simulated so lar central receiver. The transient data are cast in the form of the t ime constants for the response to radiation temperature (receiver ener gy input) and sulfur trioxide flow rate. A comparison of the predicted and measured time constants is presented and implications for the con trol of the thermochemical solar reactor are discussed.