Patent ID: 9670417
Date: 2017-06-06
CPC Classifications: B01J,C10G

Claim:
1. A fluid coking unit for converting a heavy oil feed to lower boiling products by thermal cracking in a fluid bed, comprises: (i) a reactor having a coking zone to contain a fluidized bed of solid particles into which the heavy oil feed is introduced; (ii) a scrubbing zone located above the coking zone into which vapor phase product from the coking zone is passed; (iii) a stripping zone, located at the bottom of the coking zone, for stripping at least a portion of the hydrocarbons which adhere to the solid particles passing into the stripping zone from the coking zone; (iv) a heater communicating with the stripping zone to receive solid particles from the bottom of the stripping zone; (v) a conduit for passing hot solid particles from the heater to the coking zone; (vi) a recirculation conduit for recycling hot solid particles from the heater to the stripping zone; with (vii) a centrally-apertured annular baffle at the top of the stripping zone to inhibit recirculation of solid particles from the stripping zone to the coking zone, wherein the centrally-apertured annular baffle is imperforate apart from the central aperture; wherein the recirculation conduit has an outlet at the top of the stripper zone below the centrally apertured annular baffle and above a plurality of stripper sheds.