Fluidized coking with oxygen-containing stripping gas
AssigneeExxonMobil Research and Engineering Company
InventorMohsen N. Harandi
Life of this patent
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Abstract
Systems and methods are provided for using an oxygen-containing gas as at least part of the stripping gas for the stripping zone or section in a fluidized coker. By using an oxygen-containing gas as the stripping gas, heat can be added to the stripping zone selectively based on combustion of coke and/or hydrocarbons with the oxygen in the stripping gas. This can allow the temperature of the stripping zone to be increased relative to the temperature of the coking zone of a fluidized coking system. The flow of oxygen can be controlled to achieve a desirable temperature in the stripper while the reactor temperature is independently set by preheating of the feed and/or hot coke circulation to the reaction zone.
Claims20
A method for performing fluidized coking, comprising:
- exposing a feedstock comprising a T10 distillation point of 343° C. or more to a first portion of a fluidized bed comprising solid particles in a coking zone of a reactor under thermal cracking conditions to form a 343° C.-liquid product, the thermal cracking conditions being effective for depositing coke on the solid particles;
- introducing an oxygen-containing stream into a stripping zone of the reactor, the stripping zone comprising a second portion of the fluidized bed, under stripping conditions to oxidize at least a first portion of the deposited coke, a stripping temperature of the stripping conditions being greater than a cracking temperature of the thermal cracking conditions;
- passing at least a portion of the solid particles comprising deposited coke from the reactor to at least one of a gasifier and a burner;
- exposing the at least a portion of the solid particles comprising deposited coke to oxidation conditions in the at least one of a gasifier and a burner to form partially oxidized solid particles and a gas phase product comprising CO and CO2;
- removing at least a first portion of the partially oxidized solid particles from the at least one of a gasifier and a burner;
- and
- passing at least a second portion of the partially oxidized solid particles into the coking zone of the reactor.
Dependencies are inferred from the claim text.