Abstract: The present invention provides a method of beneficiating slag, including mixing the slag with water to form a slurry. The slurry is screened through a first screen to remove a first portion of material and then screened through a second screen to remove a second portion of material. In one embodiment, the second portion of material has a carbon content less than about 5% and, more preferably, a carbon content less than about 1%.

Abstract: A novel method for producing fly ash material with a range of particle sizes from about 2.0 to about 4.0 &mgr;m is provided utilizing superplasticizers. The method produces fly ash material suitable for use as filler material in the plastics industry and super pozzolan for the concrete industry.

Abstract: A method for improving the pozzolanic character of fly ash includes the steps of first hydraulically classifying and then flotation separating the fly ash in order to reduce particle size distribution and remove carbon. The method also includes the steps of spiral concentrating separated coarse particles to recover iron, pyrite and marcasite and screening the fly ash to remove ultra-light carbon and plant debris.

Abstract: An improved froth flotation method is provided for the removal and recovery of an ultra-fine constituent such as carbon from tailings such as fly ash. A flotation apparatus is utilized that preferably includes a slurry conditioning tank and a flotation cell. The method of the present invention comprises the improvement of utilizing a flotation reagent formulation comprising a mixture of fuel oil and petroleum sulfonate. The method broadly includes the steps of (1) producing a slurry, or solid suspension, of the material containing the constituent to be recovered by adding a preselected amount of water or other slurrying liquid; (2) adding the flotation reagent comprising a mixture of fuel oil and petroleum sulfonate to the slurry that renders the selected constituent hydrophobic; (3) aerating the conditioned slurry; (4) recovering the selected ultra-fine constituent from an upper portion of the flotation apparatus; and (5) withdrawing and recovering tailings from a lower portion of the flotation apparatus.

Abstract: A froth flotation method and apparatus for the recovery of ultra-fine constituent are provided. The apparatus includes a flotation column having a drain for withdrawing tailings and underflow and an overflow for recovering the selected ultra-fine constituent. A mechanism is provided for delivering a wash medium to an upper portion of the column as well as for delivering diffuse air to a lower portion of the column. A slurry including the constituent to be recovered is received and conditioned within a tank that is connected by means of a feed line to the column. Additionally, a mechanism is provided for dissolving air in the slurry in the conditioning tank. Further, one or two matrixes may be mounted across the flotation column to further improve recovery.