Analysis of Soot Formed during the Pyrolysis of Athabasca Oil Sand Asphaltenes
Bibliographic record
Abstract
Asphaltenes are formed during the primary upgrading process of bitumen. Gasification is considered as a good option for conversion of the low-value asphaltenes into syngas. Syngas can later be used in the generation of steam for steam-assisted gravity drainage, and the hydrogen from the syngas can be used for upgrading. Understanding the decomposition of asphaltenes, the subsequent formation of soot, and the properties of soot enables optimization of the process of asphaltene gasification. In this work, the effects of feed particle size, temperature, and residence time on the formation of soot particles during the pyrolysis of Athabasca oil sand asphaltenes were investigated. Morphological, structural, and elemental properties of collected soot were also investigated. The experiments were carried out in an atmospheric entrained-flow reactor that was electrically heated to a range of set temperatures between 800 and 1400 °C, and the residence time was varied between 5 to 12 s by controlling the carrier gas nitrogen flow rate. The pyrolysis products were air-cooled in the collection probe after the reactor and passed through a cyclone to separate out particles larger than 10 μm. The particles smaller than 10 μm were subsequently passed through a cascade impactor for segregation of soot and ash particles in the size range from 0.03 to 3 μm. It was found that asphaltenes devolatilize to produce char, light gases, and tar. The different feed particle size ranges used in this study had a negligible effect on the analyzed properties of the soot. The yield of soot formed increased with the pyrolysis temperature. It was observed that the average size of primary soot particles decreases with an increase in temperature. The sulfur and hydrogen contents of soot decrease with temperature as a result of the liberation of sulfur as hydrogen sulfide during the pyrolysis reactions. With increasing residence time, the average size of the primary soot particles increases.
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".