Agglomeration of Bitumen-Coated Coke Particles in Fluid Cokers

Abstract

A simplified mathematical model is proposed to determine the agglomeration tendency of bitumen-coated coke particles in fluid cokers. The model calculates a theoretical critical velocity that depends on key parameters such as the particle size, bitumen viscosity, and bitumen thickness; it also accounts for the temperature- and reaction-dependent variations of the bitumen thickness and viscosity. A peak theoretical critical velocity at the intermediate reaction times for all coking temperatures is predicted. By comparing this peak critical velocity with the estimated inter-particle collision velocities within an industrial-scale reactor, the agglomeration tendency of coke particles is determined within fluid cokers. The results show that at low temperature regions (T=400 °C), there is no agglomeration tendency; however, at high coking temperatures (T=503 and 530 °C), substantial agglomeration tendency is expected. It is also found that the number of coke particles constituting an agglomerate could be as high as a few hundreds.

Century-Long Source Apportionment of PAHs in Athabasca Oil Sands Region Lakes Using Diagnostic Ratios and Compound-Specific Carbon Isotope Signatures

“…Coking is responsible for PAH emissions and is one of the main processes of bitumen upgrading. It is a pyrolysis reaction occurring around 500 °C that involves the cracking of complex, high molecular weight molecules into smaller ones and is associated with a significant (∼2‰) carbon isotope fractionation effect in PAHs . Since the δ 13 C values for DBT reported here at the top of the core in ALE are identical to that of the AOS aromatic fraction, we do not consider bitumen upgrading facilities as a significant source of atmospheric PAHs to our furthest study site.…”

Analysis of the effect of small amounts of liquid on gas–solid fluidization using CFD‐DEM simulations

“…Adding small amounts of liquid to granular flows and fluidized beds is necessary in a variety of processes, particularly in the energy and pharmaceuticals industries . Examples of processes in which small amounts of liquid are added include granulators, Wurster coaters, fluidized catalytic crackers, and fluid cokers …”

Review of Particle Physics and Chemistry in Fluidized Beds for Development of Comprehensive Ash Agglomeration Prediction Models

“…128 The slag layer thickness may be computed based on the slag amount and contact angle. 129 A correlation for the change in slag thickness over time in a fluid coker was developed by Darabi et al 130 Such corelations may be useful; however, they are specific to the system under study.…”