Apparatus for countercurrent contacting of gas and solids

An apparatus for the countercurrent contacting of a gas and downflowing solid particles, which comprises:

• a) a housing at least partially defining an interior space;
• b) a plurality of baffles positioned within the interior space of the housing, the baffles being arranged in at least first and second vertically spaced levels in successively lower position, each of said at least first and second levels including a row of at least two baffles oriented substantially parallel to one another and inclined from horizontal orientation so as to laterally shift the direction of downflowing particles transversely as the particles move from one level to the next lower level,
• wherein the baffles have a plurality of openings arranged in at least two parallel rows such that the openings of one row are staggered with respect to the openings of the adjacent row, and
• wherein the openings each have a diameter ranging from about 0.5 inches to about 6 inches.

A fluid catalytic cracking unit including a stripper for removing entrained hydrocarbon vapor from downflowing spent catalyst particles, the stripper comprising:

• a) a stripper housing;
• b) means for introducing a stripping gas into the stripper housing;
• and,
• c) a plurality of flat baffles positioned within the stripper housing, the baffles being arranged in at least first and second vertically spaced levels in successively lower position, each of said at least first and second levels including a row of at least two baffles oriented substantially parallel to one another and inclined from horizontal orientation so as to laterally shift the direction of downflowing catalyst particles transversely as the catalyst particles move from one level to the next lower level wherein the baffles each have first and second opposite and parallel serrated edges defining a baffle length, each serrated edge including alternate ridges and notches.

A fluid catalytic cracking unit including a stripper for removing entrained hydrocarbon vapor from downflowing spent catalyst particles, the stripper comprising:

• a) a stripper housing;
• b) means for introducing a stripping gas into the stripper housing;
• and,
• c) a plurality of flat baffles positioned within the stripper housing, the baffles being arranged in at least first and second vertically spaced levels in successively lower position, each of said at least first and second levels including a row of at least two baffles oriented substantially parallel to one another and inclined from horizontal orientation so as to laterally shift the direction of downflowing catalyst particles transversely as the catalyst particles move from one level to the next lower level, wherein the baffles each have first and second opposite and parallel serrated edges defining a baffle length, each serrated edge including alternate ridges and notches.