Abstract: This invention relates to the catalytic cracking of a hydrocarbon feed. In particular, this invention relates to an apparatus and process utilizing a catalyst stripper section of a fluid catalytic cracking (FCC) reactor with chordal trays designed to provide improved stripping of hydrocarbons from spent FCC catalyst in an FCC reactor stripping zone.

Abstract: This invention relates to the catalytic cracking of a hydrocarbon feed. In particular, this invention relates to an apparatus and process utilizing a catalyst stripper section of a fluid catalytic cracking (FCC) reactor with chordal trays designed to provide improved stripping of hydrocarbons from spent FCC catalyst in an FCC reactor stripping zone.

Abstract: This invention provides processes for maintaining a desired particle size distribution in an oxygenate to olefin reaction system. In one embodiment, the invention comprises replacing lost catalyst fines with less active co-catalyst particles. By adding less active co-catalyst particles to the reaction system, desirable fluidization characteristics and hydrodynamics can be maintained without affecting the overall (or primary catalyst) performance and product selectivities. The invention is also directed to a population of catalyst particles having a desirable particle size distribution well-suited for realizing ideal fluidization and hydrodynamic characteristics.

Abstract: A fluidized catalytic cracking system includes a riser for contacting catalyst and hydrocarbon feedstock. The riser has an inner surface that defines a central passage. The central passage acts as a flow path for the catalyst and the hydrocarbon feedstock. A plurality of ribs are disposed on the riser inner surface. The ribs increase the degree of mixing that occurs between the catalyst and the hydrocarbon feedstock within the central passage. In particular, each rib has a contoured inner wall. The contour of the inner wall forces a portion of the catalyst flow inward, toward the hydrocarbon-rich center of the central passage.

Abstract: An improved stripper section design is provided for use in fluid catalytic cracking (FCC) units. The stripper section contains means for imparting rotational movement to the FCC cracking catalyst as it traverses the stripping section. In one embodiment the stripper section contains at least one rotation vane that is preferably disposed on the surface of a stripper section tray. The rotation vane provides angular, rotational movement to the cracking catalyst as it traverses the stripper section. Vertical movement is imparted to the cracking catalyst due to gravity and radial movement is imparted to the catalyst due to the slanted nature of the tray. Through the use of the rotation vanes the contact between the catalyst particles and the stripping steam is increased, thereby improving the overall efficiency of the FCC operation.

Abstract: An improved stripper section design is provided for use in fluid catalytic cracking (FCC) units. The stripper section contains means for imparting rotational movement to the FCC cracking catalyst as it traverses the stripping section. In one embodiment the stripper section contains at least one rotation vane that is preferably disposed on the surface of a stripper section tray. The rotation vane provides angular, rotational movement to the cracking catalyst as it traverses the stripper section. Vertical movement is imparted to the cracking catalyst due to gravity and radial movement is imparted to the catalyst due to the slanted nature of the tray. Through the use of the rotation vanes the contact between the catalyst particles and the stripping steam is increased, thereby improving the overall efficiency of the FCC operation.

Abstract: A fluidized catalytic cracking (FCC) process and apparatus uses a catalyst stripper with slant trays or shed trays having "downcomers". Downcomers, vertical catalyst/gas contacting elements, provide a vertical, countercurrent region for catalyst/stripping vapor contact. The downcomers improve stripping effectiveness.