Fluid particle cooling process and apparatus

Claim 1

A process for the controlled cooling of hot fluidized catalysts which comprises: (a) passing spent catalyst having coke deposited thereon, cooled catalyst and regeneration gas containing oxygen to the lowermost portion of a catalytic combustion chamber to oxidize said coke in a relatively dense bed of fluidized catalyst; (b) passing said oxidized catalyst upward through said combustion chamber to an uppermost section of said combustion chamber containing catalyst in a relatively dilute phase; (c) passing said oxidized catalyst through said uppermost section of said combustion chamber to a surmounted disengagement chamber having a relatively dense phase of catalyst collecting in the lowermost portion of said disengagement chamber; (d) passing said catalyst from said lowermost portion of said disengagement chamber to a heat removal zone situated extrinsic from said combustion and said disengagement chamber; (e) cooling said catalyst in said extrinsic heat removal zone by indirect heat exchange against a cooling fluid entered and removed from said extrinsic heat exchange zone; (f) fluidizing said catalyst in said heat exchange zone by passage of a fluidizing gas in direct contact with said catalyst being cooled; (g) passing said cooled catalyst to said combustion chamber as the cooled catalyst of step (a), wherein said extend of fluidization in step (f) and said temperature of said regeneration system is controlled by the combination of: (i) sensing a temperature in the uppermost section of said combustion chamber having catalyst in said relatively dilute phase; (ii) transmitting said sensed temperature to a temperature controller device wherein said temperature is compared with a predetermined desired temperature set point to develop a controller output signal; (iii) transmitting said controller output signal to a flow regulation means which regulates the quantity of flow of fluidizing gas in step (f) to said extrinsic heat exchange zone; and (iv) transmitting said controller output signal to a flow regulation means which regulates the quantity of flow of cooled catalyst from said extrinsic heat exchange zone to said combustion chamber as said cooled catalyst of step (a).