Process and apparatus for fluidized catalytic cracking of a hydrocarbon feed

A process for contacting a hydrocarbon feedstock with hot solid particles within a riser reactor of a fluidized catalytic cracking system said process comprises:

• providing an elongated conduit having an interior surface, defining an inside diameter, a lift zone, a reaction zone and an injection zone located between said lift zone and said reaction zone with said interior surface of said reaction zone having disposed thereon turbulence generation means for promoting turbulence in the flow of said hydrocarbon feedstock with hot solid particles within said reaction zone, wherein said turbulence generation means includes a first surface extending from said interior surface and facing an approaching catalyst flow, and a second surface extending from said interior surface and facing opposite said approaching catalyst flow, wherein said first surface and said second surface intersect at a terminal edge distant from said interior surface, wherein the dimension from said interior surface to said terminal edge is less than 10 percent of said inside diameter, and wherein said first surface slopes in the direction of said approaching catalyst flow at an angle between about 30 to 60 degrees and said second surface slopes in an opposite direction of said approaching catalyst flow at an angle between about 5 to 25 degrees;
• introducing said hot solid particles into said lift zone wherein said hot solid particles are fluidized with a fluidization gas and lifted into said injection zone;
• introducing said hydrocarbon feedstock into said injection zone wherein said hot solid particles are mixed with said hydrocarbon feedstock;
• and
• passing said hydrocarbon feedstock with said hot solid particles into said reaction zone.

A fluidized catalytic cracking system comprising a riser reactor conduit having an interior surface defining an inside diameter, a lift zone, a reaction zone and an injection zone located between said lift zone and said reaction zone with said interior surface of said reaction zone having disposed thereon a plurality of protrusions for promoting turbulence in the flow of catalyst in said riser reactor conduit, wherein said protrusions include:

• a first surface extending from said interior surface and facing an approaching catalyst flow;
• and
• a second surface extending from said interior surface and facing opposite said approaching catalyst flow,
• wherein said first surface and said second surface intersect at a terminal edge distant from said interior surface, wherein the dimension from said interior surface to said terminal edge is less than 10 percent of said inside diameter, and wherein said first surface slopes in the direction of said approaching catalyst flow at an angle between about 30 to 60 degrees and said second surface slopes in an opposite direction of said approaching catalyst flow at an angle between about 5 to 25 degrees.