A Scanning Electron Microscope Study on Agglomeration in Petroleum Coke-Fired FBC Boiler
Bibliographic record
Abstract
Ten samples, from different FBC boiler systems burning petroleum coke, were chosen to study the development, structure and composition of deposits formed by agglomeration at various locations in the boilers. The work focused on examination of the samples by scanning electron microscopy (SEM) and dispersive X-ray analysis (EDX). Chemical analysis and other techniques were also employed. The results obtained have not brought to light any evidence of the participation of the liquid phase or of vanadium or alkaline metal compounds. The CaSO4 of the deposits is high (80 to 100%) and the agglomeration results from the prolonged sintering of CaSO4 particles, until a strong 3-dimensional framework is formed, in which other, unrelated particles may be trapped, without contributing to cohesion. While CaO is still available, “chemical sintering” associated with its conversion to CaSO4 appears to be important, but sintering also occurs by a slower mass transfer mechanism and continues after the depletion of CaO. Deposits formed in regions only reached by fly ash (convection section), and also in-bed deposits, grow from particles <50 μm, mostly very small ones, < 10 μm. Where the bed ash can collect (e.g., J-valves), the deposits grow by the sintering together of larger particles, 100–300 μm, which themselves appear to be conglomerates of smaller particles sintered together.
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 machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 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 source (direct Gemma or distilled Codex), 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".