Method and device for introducing catalyst particles into a fluidized bed catalytic reactor

摘要

The upstream part of the cracker contains at least one solid fixed packing (6) extending over all or part of the cracker cross section and forming a network of cells through which the catalyst particles pass. The network ensures at least one division and recombination of the catalyst particle flow to homogenize them over the cracker cross section. The catalytic cracker (1) contains fluid in its upstream part, and has at least one device (2) for supplying at least partly regenerated catalyst particles and at least one device (8) for injecting the load to be cracked. The packing is placed in the upstream part of the cracker, between the catalyst supply zone and the zone where the load to be cracked is injected. The cells in the packing are orientated radially to the gas and particle flow. At least part of the packing is in the form of static mixers. About 50% of the cells point in one direction and about 50% in a second direction which is at 10-90 degrees to the first. The packing is made of a series of corrugated plates cut across their corrugations and linked or welded so the peak of each corrugation forms an angle of 45-135 degrees , preferably 90 degrees to the peak of the corrugation of the next plate. At least part of the packing is made of one or more fragments of helix, juxtaposed and rotated relative to each other. At least part of the packing is a mesh or made of crossed bars stacked and welded to each other. The device contains at least two, preferably two-four packing elements as above, the same or assorted, juxtaposed or spaced out. The packing elements are made of heat and erosion resistant materials such as refractory steel or ceramic, and are arranged to handle fluidized catalyst particles at a density of 200-800 kg/m3. Downstream of the packing are deflectors to send the particles down the middle or the sides of the reactor. The deflectors have circular profiles and are annular or helical, or are rounded, hyperbolic, semicircular or semi-elliptical.