US 2003/0075480 A1 · Process for controlling oxidation of nitrogen and metals in circulating fluidized solids contacting process

Abstract

A fluidized particulate solids contacting process for reducing regenerator flue gas NOx emissions and/or permitting operating with an increased equilibrium solids vanadium level, which process may be an FCC process or a fluidized particulate solid hydrocarbon treating process, wherein spent FCC catalyst or other spent solid is in a regenerator with an oxygen-containing regeneration gas under catalyst (solid) regeneration conditions which include a combination of at least a regeneration temperature and an oxygen level in the regeneration gas which is effective to burn off the spent solid a majority of carbonaceous deposits thereon, while substantially preventing the formation of NOx, and thereby produce a regenerated solid having a carbon level reduced from that of the spent solid and a flue gas; maintaining the regenerated solid in a fluidized state with a fluidizing media that substantially prevents any further oxidation or regeneration; and returning the fluidized regenerated solid to the reactor (contactor) used in the process.

Claims15

Dependent claims

An improved circulating fluidized solids contacting process, which process comprises the steps of:

a. contacting a hydrocarbon feed in a fluidized contactor reactor with hot regenerated solid under conditions which convert the hydrocarbon feed into lower molecular weight hydrocarbon product vapors and form a spent solid containing carbonaceous deposits,
b. separating a majority of the lower molecular weight hydrocarbon product vapors from the spent solid to form separated product vapors and separated spent solid containing entrained hydrocarbon vapors,
c. processing the separated product vapors into desired product fractions,
d. subjecting the separated spent solid to stripping to remove therefrom a majority of the entrained hydrocarbon vapors,
e. contacting the resulting stripped spent solid in a regenerator with an oxygen-containing regeneration gas under solid regeneration conditions which include a combination of at least a regeneration temperature and an oxygen level in the regeneration gas which is effective to burn off the spent solid a majority of the carbonaceous deposits, while substantially preventing the formation of NOx, and thereby produce a regenerated solid having a carbon level reduced from that of the spent solid and a flue gas,
f. maintaining the regenerated solid in a fluidized state with a fluidizing media that substantially prevents any further oxidation or regeneration, and
g. returning the fluidized regenerated solid to the contactor.

4 more elements

An improved fluidized circulating solids process for treating or cracking hydrocarbon feedstocks that contain a significant content of vanadium and/or nitrogen to provide a hydrocarbon product substantially reduced in vanadium content and/or a regenerator flue gas having a low level of NOx, said apparatus comprising:

a. contacting said hydrocarbon feedstocks in a contactor with fluidized hot particulate solids under conditions to vaporize the majority of said feedstock and convert said feedstock to a lower molecular weight vapor product and form a spent solid containing carbonaceous deposits which contain the majority of feedstock vanadium,
b. separating a majority of the spent solids from the vaporized product to form separated product vapors and separated spent solids containing entrained hydrocarbon vapors,
c. processing the separated product vapors into desired products,
d. subjecting the separated spent solid to stripping to remove therefrom a majority of the entrained hydrocarbon vapors,
e. contacting the resulting stripped spent solids in a regenerator with an oxygen-containing regeneration lift gas under dilute phase regeneration conditions which include a combination of at least a regeneration temperature and an oxygen level in the regeneration gas which is effective to burn off the spent solids a majority of the carbonaceous deposits while maintaining the majority of vanadium in an oxidation state less than +5 and substantially preventing the formation of NOx,
f. controlling the regenerated solids temperature to not more than 1400° F.,
g. maintaining the resultant controlled temperature regenerated solid in a dense phase fluidized state with a fluidizing media that substantially prevents any further oxidation of the vanadium deposits or the formation of NOx, and
h. returning the fluidized regenerated solid to the contactor.

5 more elements

Dependencies are inferred from the claim text.

Process for controlling oxidation of nitrogen and metals in circulating fluidized solids contacting process

Life of this patent

Process for controlling oxidation of nitrogen and metals in circulating fluidized solids contacting process

Life of this patent

Abstract

Claims15