Beneficiation and Utilization of Coal Combustion Fly Ash: A Major Success in Reducing Solid Waste and Increasing Supplies of Construction Materials While Reducing Green House Gas Emissions
Bibliographic record
Abstract
This paper will discuss how utilizing fly ash as a supplementary cementitious material in concrete enables production of concrete of equivalent or higher strength and durability while using lower quantities of ordinary Portland cement (OPC). With the inherent generation of carbon dioxide from the calcining of calcium carbonate and fossil fuel consumption associated with mining and pyroprocessing, approximately 1 ton of CO2 is emitted per ton of OPC produced. Using fly ash as an OPC replacement results in avoidance of CO2 emissions on a nearly ton for ton basis. Over 70 million tons of fly ash are generated by coal-fired power plants annually in the USA, most of which is disposed of in land fills. Only approximately 12 million tons of fly ash is used to replace OPC in the production of concrete annually. Fly ash used in concrete production is limited to material meeting chemical and physical specifications to assure strength and durability properties of the concrete. Separation Technologies LLC (ST) has developed and implemented innovative, patented processes to reduce unburned carbon and detrimental ammonia levels in coal fly ash for use in concrete production. Separation Technologies’ processes for beneficiation of coal fly ash produce a highly useful cement substitute from a solid waste while creating no further emissions or wastes by selective removal of unburned carbon and ammonia from the material. Simultaneously, a carbon rich stream of material is collected, recovering an otherwise wasted fuel, reducing coal use and largely eliminating solid waste disposal at the power plant. ST has commercial operations at eight large coal-fired electric power plants in the United States, Canada and the United Kingdom. ST has produced 5 million tons of concrete grade material from otherwise poor quality fly ash. Expansion of the available supply of high quality fly ash through ST’s beneficiation processes enables more concrete producers to expand and optimize concrete mix designs, further reducing green house gas (GHG) emissions. The presentation will include a comparison of GHG emission reductions using various alternative cementitious materials and mix designs.
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 | 0.001 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.001 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.002 | 0.001 |
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".