Process to reduce NO/sub chi/ emissions from a fluid catalytic cracking unit

Patent · Tue Sep 19 04:00:00 EDT 1989

OSTI ID:5425952

Herbst, J A; Owen, H; Schipper, P H

This patent describes a process for fluidized bed regeneration of coke contaminated catalyst by combining a stream of coked catalyst with a stream of hot regenerated catalyst and a first oxygen-containing gas stream to form a first mixture of catalyst and gas and regenerating the catalyst by burning the coke. It is characterized by passing the mixture through a first stage regenerator comprising a first regenerator riser having an upper end and a lower end and maintaining a low oxygen concentration in the upper end of the riser to form a catalyst and flue gas stream; simultaneously discharging the catalyst and flue gas stream from the upper end of the riser and separating the catalyst and flue gas stream into a catalyst rich stream which is discharged down to form a first catalyst bed located in a lower portion of a second stage regenerator and a first flue gas stream which is removed as a first flue gas stream from the regenerator; adding a second oxygen-containing stream to the first catalyst had to form a second mixture of catalyst and gas which passes to an upper portion of the second stage regenerator and maintaining a low oxygen concentration in the upper portion of the second stage regenerator; and discharging from the upper portion of the second stage regenerator catalyst with reduced coke content and flue gas and separating catalyst with reduced coke content from the flue gas and forming a second dense bend of catalyst and a second flue gas stream; and recycling to the first stage regenerator a catalyst stream obtained from the second dense bed.

• Assignee: Mobil Oil Corp., New York, NY
• Patent Number(s): US 4868144
• Application Number: PPN: US 7188810A
• OSTI ID: 5425952
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
020400* -- Petroleum-- Processing
020800 -- Petroleum-- Waste Management
54 ENVIRONMENTAL SCIENCES
540120 -- Environment
Atmospheric-- Chemicals Monitoring & Transport-- (1990-)
AIR POLLUTION CONTROL
CATALYSTS
CATALYTIC CRACKING
CHALCOGENIDES
CHEMICAL REACTIONS
CHEMICAL REACTORS
CONTROL
CRACKING
DECOMPOSITION
DENITRATION
ENERGY SOURCES
FLUE GAS
FOSSIL FUELS
FUELS
GASEOUS WASTES
NITROGEN COMPOUNDS
NITROGEN OXIDES
OXIDES
OXYGEN COMPOUNDS
PETROLEUM
POLLUTION CONTROL
PYROLYSIS
REGENERATION
THERMOCHEMICAL PROCESSES
WASTES