Investigation of a Canadian Ilmenite as an Oxygen Carrier for Chemical Looping Combustion
Bibliographic record
Abstract
The use of chemical looping combustion (CLC) for power generation is an advanced energy technology that can capture CO 2 inherently, which could prove to be the next electricity generation technology in a carbon-constrained future. For commercial-scale application of the CLC process, the availability of cost-effective oxygen carriers (OCs) with stable performance is imperative. Given the composition of ilmenite, there may be potential for its application as a cost-effective alternative OC for CLC. In this study, the performance of a Canadian ilmenite was investigated and showed promising results. Complete reduction of ilmenite takes a relatively long time; therefore, it is not practical for ilmenite to reach its maximum oxygen transport capacity by counter-balance of capital investment in the fuel reactor. Reduction in the first 30 min was selected as the effective reaction for the application of CLC, which gave an oxygen transport capacity of about 5.52%. To understand the phase and Fe valence state (Fe 3+ /Fe 2+ ) transformations of calcined and reacted ilmenite, transmission electron microscopy (TEM) and electron energy-loss spectroscopy (EELS) were conducted. Using X-ray diffraction (XRD), the effective reaction was identified as Fe 3+ reduced to Fe 2+ at test conditions. The kinetics of this reaction were studied by doing experiments under different gas concentrations and temperatures based on a shrinking core model. The results showed that the activation energy was 169.6 × 10 3 J mol –1 with a reaction order of approximately 2.2. The chemical stability of the OC was studied by doing multiple redox cycles. To qualitatively show the difference between ilmenite and a synthetic OC, a freeze-granulated OC with a composition of 50 wt % Fe 2 O 3 and 50 wt % Al 2 O 3 was selected as a reference. The average reaction rate and crushing strength of each sample were compared. The results showed that ilmenite has favorable stability characteristics to be a viable, cost-effective OC for power generation.
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 | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.001 | 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".