Engineering Commons^™

Mitigation Of Fouling And Liquid Losses In A Fluid Coker™: Influence Of Operating Conditions And Internals On Wet-Agglomerates Contribution To Liquid Carry-Under, Yohann Alain François Cochet

Electronic Thesis and Dissertation Repository

In Fluid Cokers, heavy oil is sprayed into a fluidized bed of hot particles through feed ring nozzles located at different heights. Unreacted or partially reacted feedstock, trapped in wet‑agglomerates, reaches the reactor bottom where it causes fouling or is lost to the system burner. The thesis objective is to determine whether modifying the feed distribution between rings or adding baffles can reduce the amount of liquid reaching the reactor bottom.

A model was developed to predict the amount of liquid reaching the reactor bottom. It integrates models for agglomerate formation and rewetting in spray jets, agglomerate drying through heat …

Particle Entrainment Studies From Dry And Wet Bed, Saber Ayatollahi

Electronic Thesis and Dissertation Repository

During the Fluid Coking Process™ bitumen is sprayed into a fluidized bed of hot coke particles. The bitumen undergoes thermal cracking and is converted into gasses, condensable vapors, and solid coke, which deposits on the coke particles. These vapors rise through the vessel and result in entrainment of coke particles. Wet fine coke particles from the freeboard region enter the cyclone and contribute to the fouling of the Coker cyclones which can lead to the premature shut-down of Fluid Cokers.

The primary objective of this research is to determine how bed wetness affects entrainment.

First, a new fluidized bed was …

Hydrodynamics In Recirculating Fluidized Bed Mimicking The Stripper Section Of The Fluid Coker, Francisco J. Sanchez Careaga

Electronic Thesis and Dissertation Repository

The stripper section of a Fluid Coker^TM consists of a system of baffles (sheds) that enhances the removal of interstitial and adsorbed hydrocarbon vapors from the fluidized coke-particles. Most of the hydrocarbon-vapors released below a stripper shed flow up to the stripper shed, where they may crack and form coke deposits that foul the shed. Extensive fouling changes the shapes of the sheds, makes them thicker and reduces the free-space between the adjacent sheds until downward solids flow is so impaired that the Coker has to be shut down.

The Radioactive Particle Tracking (RPT) technique allows the determination of …