A novel circulating cross-flow moving bed reactor system for gas—solids contacting

Abstract

A novel circulating cross-flow moving bed reactor system for gas—solids contacting is presented. The system comprises a bunker, an inclined reactor, a stripper, a regenerator, a second stripper, a vertical transport system, and a gas—solids separator. It is an option for highly selective regenerative solid catalytic processes with a short gas residence time (up to seconds) and a moderate catalyst residence time (up to minutes). A laboratory-scale test rig of the circulating cross-flow moving bed reactor system is described along with an experimental study to verify its practical feasibility. The set-up operates under ambient conditions and 1.6 mm porous spherical alumina particles have been used. The feasibility of obtaining a stable continuous solids flow in the circulating system was shown. Further research focused on the reactor which has been constructed from four geometric equal compartments. The minimum superficial gas velocity below which the solids do not flow has been determined, as well as the maximum superficial gas velocity in the reactor above which fluidisation and the formation of gas bubbles occurs. Radioactive gas and solids tracer experiments have been performed to study the gas and solids flow patterns in the reactor. The lateral gas flow to neighbouring compartments in the reactor has been quantified. The solids move in plug flow unless gas bubble formation occurs.