Abstract: A process and apparatus for multi-stage fluidized bed regeneration of spent FCC catalyst in a single vessel. At least two isolated relatively dense phase fluidized beds are disposed beneath a common dilute phase region. Spent catalyst discharged into a primary regeneration stage is regenerated to produce flue gas and partially regenerated catalyst, which preferably overflows into the second stage. Flue gas and entrained catalyst from each fluidized bed are processed in two trains of separation means, preferably cyclones. The inlets of each train are disposed above the isolated fluidized beds, and are effectively separated although sharing an open dilute phase region.

Abstract: The present invention features the use of a particulate sorbent and a particulate FCC catalyst, which are physically separable, sequentially in the same FCC riser, followed by separation of commingled spent catalyst and sorbent particles from vapors, and the subsequent primary partial regeneration and heat up of spent sorbent particles and catalysts particles in an oxygen deficient burning zone, followed by physical separation of partially regenerated catalyst and sorbent particles, preferably using a cyclonic classifier to effect the separation. This is followed by secondary regeneration of the resulting segregated partially regenerated sorbent and catalyst streams in oxygen rich combustion zones to fully regenerate sorbent and catalyst particles.

Abstract: An electrostatic precipitator apparatus and method which minimizes reentrainment of collected particles during their removal from the collecting electrode by use of a collecting system including concentric semi-tubes which are configurable from a position exposed to gas flow to one protected therefrom.

Abstract: A fluid catalytic cracking unit equipped with multiple feed injection points along the length of the riser is operated such that all of the fresh feed is charged to one of different feed injection points, depending on the ratio of light distillate (gasoline) to middle distillate (light catalytic gas oil) that is desired in the product slate. When all of the fresh feed is charged to one of the upper injection points in the riser in order to increase middle distillate yield, the unconverted slurry oil (650.degree. F.+material) can be recycled to a location below the injection point of the fresh feed so as to increase conversion to middle distillate while lowering the activity of the catalyst (via coke deposition) for single pass conversion of the fresh feed. Steam in excess of levels typically employed for dispersion is used at the bottom of the riser to lift the regenerated catalyst up to the feed injection points.

Abstract: The present invention features the use of a particulate sorbent and a particulate FCC catalyst, which are physically separable, sequentially in the same FCC riser, followed by separation of commingled spent catalyst and sorbent particles from vapors, and the subsequent primary partial regeneration and heat up of spent sorbent particles and catalysts particles in an oxygen deficient burning zone, followed by physical separation of partially regenerated catalyst and sorbent particles, preferably using a cyclonic classifier to effect the separation. This is followed by secondary regeneration of the resulting segregated partially regenerated sorbent and catalyst streams in oxygen rich combustion zones to fully regenerate sorbent and catalyst particles.

Abstract: A method for separating particulate solids from a gaseous stream laden with the solids includes discharging the gaseous stream with a swirling movement downwardly into a containment vessel, and impinging the stream on a bed of the separated solids maintained at the lower end of the vessel to reverse the direction of gas flow upwardly through a return zone which encircles the core zone. The gaseous stream is withdrawn from the return zone at the upper end of the vessel and, optionally, may be passed from the return zone to a second stage separation zone, such as one or more cyclone separators, for removal of residual particulate solids from the gaseous stream. Apparatus of the invention includes a flow-constricting nozzle mounted on a containment vessel and having flow guide vanes and/or gas injection nozzles associated therewith to impart a swirling motion to the gaseous stream which is discharged from the nozzle downwardly into the containment vessel.