Modeling Coke Distribution above the Freeboard of a FLUID COKING Reactor
Bibliographic record
Abstract
In a FLUID COKING unit, reactor cyclone fouling by coke deposits can set the run length of the unit. Over time the coke deposits can grow and obstruct the cyclone which will limit throughput and lead to a shutdown. For this reason, producing a more uniform coke distribution pattern within the reactor horn chamber may lead to an increased interval between turnarounds. An existing pilot-scale experimental model of the coker reactor freeboard, horn chamber, and exit cyclones allows determination of coke distribution to the cyclones, but provides limited understanding of the underlying fluid dynamics within the system. In this work a two-phase computational fluid dynamics (CFD) model of this experimental rig was developed. Coke was modeled as an Eulerian stream of solid particles with monodisperse particle diameter. It was found that predicted coke distributions were sensitive to the choice of coke diameter, but a suitable choice gave good agreement with experimental observations. In the current work this value was 167 μm which was substantially higher than the value of the Sauter mean diameter of 139 μm. It was found that the CFD model could quantitatively predict coke distributions in the freeboard region of a FLUID COKING reactor experimental rig, while providing insight into the flow dynamics. When modeling the particle size distribution with a monodisperse particle diameter, comparison with experimental results is necessary to identify the coke particle diameter that leads to optimal model performance.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.002 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.001 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.001 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".