Reducing NO sub x emissions from FCC regenerators by segregated cracking of feed

Patent · Tue Jan 15 04:00:00 EST 1991

OSTI ID:6024222

Sapre, A V

This patent describes improvement in a fluidized catalytic cracking process wherein a fresh feed mixture of high and low nitrogen containing hydrocarbon feeds contact a source of hot regenerated catalyst in the base of a riser cracking reactor means to produce catalytically cracked products and spent catalyst containing coke contaminated with nitrogen compounds, wherein the spent catalyst is stripped in a catalyst stripping means to produce stripped catalyst which is regenerated in a catalyst regeneration means to produce a regenerated catalyst which is recycled to the cracking reactor means, and wherein a flue gas comprising nitrogen oxides (NO{sub {ital x}}) is withdrawn from the regenerator. The improvement comprises: segregating the fresh feed mixture into at least two different fresh feed fractions having different nitrogen contents, the segregated feed fractions comprising a low nitrogen content fresh feed and a high nitrogen content fresh feed having at least a 50% greater concentration of nitrogen than the low nitrogen content fresh feed, adding the high nitrogen content fresh feed via a feed addition means at an elevation in the base of the riser reactor, and separately adding the low nitrogen content fresh feed to the riser reactor at a higher elevation in the riser reactor and downstream of the point of addition of the high nitrogen content fresh feed, whereby the NO{sub {ital x}} content of the flue gas is reduced relative to operation with a feed comprising a mixture of the high and the low nitrogen containing feedstocks.

• Assignee: Mobil Oil Corp., Fairfax, VA (USA)
• Patent Number(s): A; US 4985133
• Application Number: PPN: US 7-479308
• OSTI ID: 6024222
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
020400* -- Petroleum-- Processing
020900 -- Petroleum-- Environmental Aspects
54 ENVIRONMENTAL SCIENCES
540120 -- Environment
Atmospheric-- Chemicals Monitoring & Transport-- (1990-)
AIR POLLUTION CONTROL
CATALYTIC CRACKING
CHALCOGENIDES
CHEMICAL REACTIONS
CHEMICAL REACTORS
CONTROL
CRACKING
DECOMPOSITION
EMISSION
ENERGY SOURCES
FOSSIL FUELS
FUELS
NITROGEN COMPOUNDS
NITROGEN OXIDES
OXIDES
OXYGEN COMPOUNDS
PETROLEUM
POLLUTION CONTROL
PYROLYSIS
THERMOCHEMICAL PROCESSES