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US3857794A Expired / Lapsed US ⏱️ 0.0 years remaining

Oxygen control by injection of a reducing gas in a catalyst regenerator

Assignee: Chevron USA Inc
•
Filing: 1971-09-22
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Granted: 1974-12-31
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Expires: 1991-09-22
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Abstract

Abstract In a process for reducing the amount of oxygen in the effluent gases from a catalytic cracker regenerator, and thus controlling after-burning, a reducing gas such as carbon monoxide or hydrogen is injected into the regenerator above the bed of catalyst being regenerated. Preferably the amount of reducing gas is automatically controlled responsive to the oxygen content of the effluent flue gases from the regenerator. Preferably the reducing gas is introduced through at least three nozzles into the regenerator. Preferably the nozzles are located in substantially different positions within the regenerator above the bed of catalyst being regenerated, and the amount of reducing gas flow through each nozzle is controlled responsive to oxygen content of the effluent flue gases from the regenerator.

Inventors

  • 👤 E Carey

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-27 09:26
CPC Classifications
B; B01; B01J; B01J8/00; B01J8/18; B01J8/1809; C; C10; C10G; C10G11/00; C10G11/14; C10G11/18; C10G11/187; B01J2208/00; B01J2208/00008; B01J2208/00548

Claims Analysis

Total Claims: 5
Claim 1
Independent Claim 93 words
A CRACKING CATALYST REGENERATION PROCESS FOR ALLOWING ENRICHED OXYGEN CONTENT AND HIGH TEMPERATURES OF AT LEAST ABOUT 1, 175*F; TO EXIST IN A DENSE PHASE BED OF CATALYST PARTICLES IN A FLUIDIZED BED, DENSE PHASE-DILUTE PHASE CATALYTIC CRACKER REGENERATOR, AND FOR REDUCING UNCONTROLLED AFTERBURNING IN THE REGENERATOR, WHICH COMPRISES INJECTING A REDUCING GAS SELECTED FROM THE GROUP CONSISTING OF HYDROGEN AND CARBON MONOXIDE THROUGH AT LEAST THREE NOZZLES LOCATED WITHIN THE FIRST 20 FEET OF THE LENGTH OF THE REGENERATOR ABOVE THE TOP OF THE DENSE PHASE BED OF CATALYST PARTICLES BEING REGENERATED,
Claim 2
Dependent Claim 93 words
A CRACKING CATALYST REGENERATION PROCESS FOR ALLOWING ENRICHED OXYGEN CONTENT AND HIGH TEMPERATURES OF AT LEAST ABOUT 1, 175*F; TO EXIST IN A DENSE PHASE BED OF CATALYST PARTICLES IN A FLUIDIZED BED, DENSE PHASE-DILUTE PHASE CATALYTIC CRACKER REGENERATOR, AND FOR REDUCING UNCONTROLLED AFTERBURNING IN THE REGENERATOR, WHICH COMPRISES INJECTING A REDUCING GAS SELECTED FROM THE GROUP CONSISTING OF HYDROGEN AND CARBON MONOXIDE THROUGH AT LEAST THREE NOZZLES LOCATED WITHIN THE FIRST 20 FEET OF THE LENGTH OF THE REGENERATOR ABOVE THE TOP OF THE DENSE PHASE BED OF CATALYST PARTICLES BEING REGENERATED,
Claim 3
Dependent Claim 33 words
A process according to claim 1 wherein the amount of hydrogen or carbon monoxide gas flow through each nozzle is controlled responsive to oxygen content of the effluent flue gases from the regenerator.
Claim 4
Dependent Claim 44 words
The process in accordance with claim 1 wherein the nozzles are located zero to seven feet above the top of the dense phase bed of catalyst particles so that the reducing gas is injected within seven feet of the top of the dense phase.
Claim 5
Dependent Claim 20 words
The process in accordance with claim 1 wherein the reducing gas is a hydrogen-rich off-gas from a catalytic reforming unit.

References Cited (Backward Citations)

US2391327A Cited
US2414883A Cited
US2458862A Cited
US2436041A Cited
US2393839A Cited
US2454373A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1977-12-30 1978-07-01 1978-12-31 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1981-12-30 1982-07-01 1982-12-31 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1985-12-30 1986-07-01 1986-12-31 $7700.00 Window Closed / Lapsed

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