Production of an iron concentrate by caustic digestion of power-plant fly ash
The objective of this work was to determine how the magnetic fraction of coal fly ash could be used as an iron ore. To do this, three areas were examined: the characteristics of fly ash, the iron and steel industry, and the processing and specifications for iron ores currently in use. Methods of beneficiating the iron-rich fraction for use with conventional ironmaking technology were considered as well as the potential for producing an iron product without pretreatment. Experimental work in this study included evaluation of the effectiveness of potential physical and chemical beneficiation techniques. Some of the conclusions are: (1) magnetic fly ash can be used as an iron ore without beneficiation of any sort; (2) processing required to properly beneficiate magnetic fly ash includes upgrading both the physical and chemical properties of the ash; (3) minor components in the magnetic ash such as copper, zinc, lead and others which are detrimental in steelmaking do not appear to be a major factor in the use of magnetic fly ash as an iron ore; (4) commercial beneficiation technique use for iron ore are not applicable for treating magnetic fly ash; (5) high-grade iron concentrate can be produced by leaching magnetic fly ash in a concentrated sodium hydroxide solution; (6) caustic strength has the greatest effect of the operating variables tested on the removal of silica and alumina; (7) another important variable is solid-liquid ratio; (8) sodium aluminosilicate precipitate formed is acid soluble; (9) temperatures of 150, 200 and 250/sup 0/C were found to have little effect on the total removal of gangue; (10) extraction time was also found to have little effect on the removal of silica and alumina; (11) economics of caustic extraction as a beneficiation process are poor. 28 figures, 28 tables.
- Research Organization:
- Ames Lab., IA (USA)
- DOE Contract Number:
- W-7405-ENG-82
- OSTI ID:
- 6805943
- Report Number(s):
- IS-T-999; ON: DE83004961
- Country of Publication:
- United States
- Language:
- English
Similar Records
Production of an iron ore concentrate from the iron-rich fraction of power plant fly ash
Advanced research and technology: direct utilization-recovery of minerals from coal fly ash. Fossil energy program. Technical progress report, 1 April-30 June 1980
Related Subjects
010800* -- Coal
Lignite
& Peat-- Waste Management
32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION
320305 -- Energy Conservation
Consumption
& Utilization-- Industrial & Agricultural Processes-- Industrial Waste Management
AEROSOL WASTES
ALKALI METAL COMPOUNDS
ASHES
CHALCOGENIDES
CHEMICAL COMPOSITION
COMMINUTION
CONCENTRATORS
DATA
EXPERIMENTAL DATA
EXTRACTION
FLY ASH
FOSSIL-FUEL POWER PLANTS
GRINDING
HYDROGEN COMPOUNDS
HYDROXIDES
INFORMATION
IRON COMPOUNDS
IRON ORES
IRON OXIDES
MACHINING
MAGNETIC SEPARATORS
NUMERICAL DATA
ORE PROCESSING
ORES
OXIDES
OXYGEN COMPOUNDS
PARTICLE SIZE
POWER PLANTS
PROCESSING
RECOVERY
RESIDUES
SEPARATION PROCESSES
SIZE
SODIUM COMPOUNDS
SODIUM HYDROXIDES
THERMAL POWER PLANTS
TRANSITION ELEMENT COMPOUNDS
WASTE PRODUCT UTILIZATION
WASTES