Behavior of Metals during Combustion of Industrial Organic Wastes in Supercritical Water
Why this work is in the frame
A frame that forgets how it found something cannot be audited. These are the routes that admitted this work.
Bibliographic record
Abstract
De-inking solid residue (DISR) doped with nitrates of 2000 mg/kg of Pb, Cd, and Cr was burned in supercritical water in a batch reactor. Combustion runs were carried out under supercritical water conditions: 30.6 MPa, 450 or 525 °C, and 17.1% or 65.7% excess oxygen. The run time varied between 5 and 30 min. In all runs, more than 99.2% (up to 100%) of the Pb precipitated to ash, with leachability varying from 0.5% to 7.3% and decreasing with increasing run time and temperature. In runs at 450 °C, the soluble Cd concentration showed little or no change, but its ash's leachability dropped when more oxygen was added. At 65.7% excess oxygen, when temperature was increased from 450 to 525 °C, the Cd concentration and ash leachability declined, and a downward trend appeared with longer run time. In runs at 450 °C and 17.1% excess oxygen, the soluble Cr concentration increased with time from 4.1% (5 min) to 19.2% (30 min). When 65.7% oxygen was applied, it declined to 12.6% at 30 min, which was followed by an increase from 15.0% (5 min) to 37.5% (15 min). In the runs with 65.7% oxygen, as the temperature went up from 450 to 525 °C, the soluble Cr concentration rose to 26.1% at 5 min and subsequently showed a trend similar to that observed for the runs at 450 °C. At 30.6 MPa, 525 °C, and a 30-min run time, 100% of the Pb, 97.6% of the Cd, and 87.3% of the Cr were converted to an insoluble substance. Only 0.5% of the Pb, 0.6% of the Cd and 0.8% of the Cr in ash were leached. Tests with 20,000 mg/kg Pb, Cd, and Cr were conducted under the same conditions (pressure/temperature/time). Only 0.03% of the Pb but 82.0% of the Cd and 79.4% of the Cr remained soluble. It was found that CO 2 and acetate from organics combustion could help to remove heavy metals via formation of insoluble carbonate salts. X-ray diffraction spectra indicated the presence of PbCrO 4 and Al 2 Si 2 O 5 (OH) 4 in the ash. Electron microprobe results showed a close connection between Pb and Cr but no relation between Pb and Cd in the ash. The main solid products were CdO, CdCO 3, CrO 2, HCrO 2, PbCrO 4, PbCO 3 and PbO x . In general, the “combustion” of DISR in supercritical water showed an effective removal of heavy metals.
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.
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 | 0.001 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 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 | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.003 | 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 it