Production of inorganic pellet binders from fly ash. [Quarterly] technical report, September 1--November 30, 1994

Fly ash is produced by all coal-fired utilities, and it must be removed from the plant exhaust gases, collected, and disposed of. While much work has been done in the past to utilize fly ash rather than disposing of it, we nevertheless do not find widespread examples of successful industrial utilization. This is because past work has tended to find uses only for high-quality, easily-utilized fly ashes, which account for less than 25% of the fly ash that is produced. The main factor which makes fly ashes unusable is a high unburned carbon content. In this project, physical separation technologies are being used to remove this carbon, and to convert these unusable fly ashes into usable products. The main application being studied for the processed fly ash is as a binder for inorganic materials, such as iron-ore pellets. The project began in the current quarter. Work has concentrated on obtaining samples of all of the materials to be used (fly ash, and magnetite ore). Also, several batches of magnetite pellets were made in the research laboratories of a commercial producer of iron-ore pellets, using conventional binders. These pellets were then tested to provide a baseline for comparison with the future work to be done with fly-ash as a binder. A laboratory-scale pelletizing drum was also provided by the iron ore pellet producer, which was transported to the MTU research labs so that test pellets could be made on-site