GB1121157A - Process and apparatus for the catalytic cracking of hydrocarbon oils - Google Patents

Abstract

A process for the catalytic cracking of hydrocarbon oils comprises circulating a fluidized catalyst through a reactor zone 1, a stripping zone 2 and a regeneration zone 3, the reactor zone and the stripping zone being in direct communication with each other accommodated in a combined reactor/stripper which is free of connecting lines while the regeneration zone is accommodated in a separate regenerator, the reactor as a whole and the <PICT:1121157/C4-C5/1> stripper at least in part being located above the regenerator and the vertical centre lines of reactor and regenerator being spaced apart at most to such an extent that (i) the transport of the catalyst particles from the stripping zone to the regeneration zone takes place vertically, the catalyst particles being introduced directly into the fluidized bed present in the regenerator at a point higher than the point of discharge of the regenerated catalyst from the regenerator, and (ii) the transport of the feedstock and fluidized catalyst through the riser for the reactor likewise take place vertically. The reactor 1 is connected to a discharge line 7 for cracked product, a vertical supply line 6 for the feedstock and regenerated catalyst; the stripper 2 is provided with a steam supply line 8, a vertical line 9 from the stripper debouching laterally into regenerator 3 provided with a slide valve 15, a valved connecting line 5 from the bottom of the regenerator 3 to the supply line 6 and inlet 10 and outlet 11 for the fluidizing/oxidizing agent for the regenerator. Variations may be made in the construction of the stripper in the form of a tubular element which either joins on to the reactor wall (Fig. 5, not shown) or is arranged partly inside the reactor itself (Figs. 6 and 7, not shown). The stripper is preferably provided with a plurality of baffles 13 and the regenerator with one or more grids 14.