Quench assembly design

Abstract

According to this invention, a quench assembly having improved mixing efficiency comprises a series of mixing zones: quench fluid inlet zone; quench mixing zone; a jet stirred mixing zone; and a distributor zone. In the quench fluid inlet zone, quench fluid is introduced to fluid from the catalytic bed above. The quench fluid is introduced through holes in a quench pipe, creating jets of quench fluid which entrain and mix the reactant fluid, typically partially reacted, from the bed above. This mixing zone is separated from the quench mixing zone by means of a horizontally disposed plate having a central opening therein. The reaction fluid and quench fluid enter the quench mixing zone through the central opening in the plate separating the two zones and impinge on a bottom quench mixing zone plate, where the gases are turned radially outward and passed over and around a series of mixing baffles. A plurality of pipes is located in an annular ring near the periphery of the bottom plate of the quench mixing zone for introduction of the quench gas and process fluid into a jet stirred mixing zone. Thus, the flow of fluids coming out of the quench mixing zone is introduced in a swirling direction into the jet stirred annular mixing zone, where the fluids are further mixed by mutual entrainment. Next, the fluid is turned downwardly through a central opening in a plate separating the jet stirred zone from the distributor zone. The distributor zone is provided with a distributor tray for distributing the fluid to the catalyst bed below.