Multi-stage fluidization and segregation of used catalyst fractions

Claim 2

A process for segregating used contaminated catalyst, comprising the steps of: (a) introducing the used catalyst into a first compartment of a concentric walled container, said first compartment having an upper end which has a cross-sectional area of 10 to 95 percent of that of the lower end of said first compartment; (b) fluidizing the catalyst in said first compartment with an upflowing liquid to achieve segregation of the used catalyst particles to provide a lower density less contaminated fraction at the compartment upper end, and a greater density more contaminated catalyst fraction at the compartment lower end; (c) further fluidizing the catalyst bed and transferring the less contaminated upper fraction over the top of the first compartment into a second compartment; (d) withdrawing the less contaminated catalyst fraction from the second compartment; and (e) withdrawing the more contaminated catalyst fraction from the first compartment.

Claim 3

The process of claim 1 wherein the first compartment is the outer annular space between two concentric walled containers, and the second compartment is the inner compartment.

Claim 4

The process of claim 1 in which the lower density catalyst portion transferred into the second compartment is dried therein by a gas, prior to withdrawal of the dried catalyst therefrom.

Claim 5

The process of claim 1 wherein the used catalyst has average particle density of 1.0 to 3.0 gm/cc and is fluidized by a light hydrocarbon liquid fraction having specific gravity of 0.6 to 1.3.

Claim 6

The process of claim 1 wherein the upper 30-70 percent fraction of the catalyst bed in the first compartment is transferred to the second compartment by further fluidization of the bed.

Claim 7

A process for segregating used contaminated catalyst in a two-compartment container, comprising the steps of: (a) introducing the used catalyst into the inner compartment of the two concentric walled container, said inner compartment having an upper end which has a cross-sectional area of 10 to 95 percent of that of the lower end of said inner compartment; (b) fluidizing the catalyst in said inner compartment with an upflowing liquid to achieve segregation of the used catalyst particles into a lower density, less contaminated fraction at the compartment upper end, and a greater density, more contaminated catalyst fraction at the compartment lower end; (c) further fluidizing the lens contaminated upper fraction of catalyst and transferring it over the top of the inner compartment into the outer annular compartment; (d) withdrawing the less contaminated catalyst fraction from the outer compartment; and (e) withdrawing the remaining more contaminated catalyst fraction from the inner compartment.

Claim 8

A process for segregating used contaminated catalyst in a two-compartment container, comprising the steps of: (a) introducing the used catalyst into the inner compartment of the two concentric walled container, said inner compartment having an upper end which has a cross-sectional area of 10 to 95 percent of that of the lower end of said inner compartment; (b) fluidizing the catalyst in said inner compartment with an upflowing liquid to achieve segregation of the used catalyst particles into a lower density, less contaminated fraction at the compartment upper end, and a greater density, more contaminated catalyst fraction at the compartment lower end; (c) further fluidizing the lens contaminated upper fraction of catalyst and transferring it over the top of the inner compartment into the outer annular compartment; (d) withdrawing the less contaminated catalyst fraction from the outer compartment; and (e) withdrawing the remaining more contaminated catalyst fraction from the inner compartment.