Separation of cenospheres from fly ash
AssigneeWisconsin Electric Power Company
InventorsBruce W. Ramme, John J. Noegel, Pradeep K. Rohatgi
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Abstract
Methods for increasing the amount of cenospheres in a fly ash sample are disclosed. The cenospheres are obtained in a dry state by using air as the “fluid” media for separation. In one version, the invention is a two step process, that is, screen by size followed by density separation such as in a fluidizing vertical column by density. In another version of the invention, the separation by density is followed by screening by size. Additional cycles can improve purity as defined by concentration of cenospheres.
Claims37
A method for increasing the amount of cenospheres in a fly ash sample, the method comprising:
- (a) providing an amount of fly ash having an initial percentage of cenospheres;
- (b) separating the amount of fly ash into a first fraction of fly ash having particle sizes greater than a predetermined particle size and a second fraction of fly ash having particle sizes less than or equal to the predetermined particle size;
- and
- (c) separating the first fraction of fly ash or the second fraction of fly ash into a third fraction of fly ash having particle densities greater than a predetermined particle density and a fourth fraction of fly ash having particle densities less than or equal to the predetermined particle density such that the fourth fraction of fly ash has a percentage of cenospheres greater than the initial percentage,
- wherein the initial percentage of cenospheres and the percentage of cenospheres in the fourth fraction of fly ash are volume percentages or weight percentages and at least some of the cenospheres in the fourth fraction of fly ash have a density greater than 1 g/cc.
A method for increasing the amount of cenospheres in a fly ash sample, the method comprising:
- (a) providing an amount of fly ash having an initial percentage of cenospheres;
- (b) classifying the amount of fly ash into a first fraction of fly ash having particle densities greater than a predetermined particle density and a second fraction of fly ash having particle densities less than or equal to the predetermined particle density;
- and
- (c) separating the first fraction of fly ash or the second fraction of fly ash into a third fraction of fly ash having particle sizes less than or equal to a predetermined particle size and a fourth fraction of fly ash having particle sizes greater than the predetermined particle size such that the fourth fraction of fly ash has a percentage of cenospheres greater than the initial percentage,
- wherein the initial percentage of cenospheres and the percentage of cenospheres in the fourth fraction of fly ash are volume percentages or weight percentages, and
- wherein step (b) comprises classifying the amount of fly ash in the absence of water.
A method for increasing the amount of cenospheres in a fly ash sample, the method comprising:
- (a) providing an amount of fly ash having an initial percentage of cenospheres;
- (b) classifying the amount of fly ash into a first fraction of fly ash having particle densities greater than a predetermined particle density and a second fraction of fly ash having particle densities less than or equal to the predetermined particle density;
- and
- (c) separating the first fraction of fly ash or the second fraction of fly ash into a third fraction of fly ash having particle sizes less than or equal to a predetermined particle size and a fourth fraction of fly ash having particle sizes greater than the predetermined particle size such that the fourth fraction of fly ash has a percentage of cenospheres greater than the initial percentage,
- wherein the initial percentage of cenospheres and the percentage of cenospheres in the fourth fraction of fly ash are volume percentages or weight percentages, and
- wherein step (b) and step (c) are completed in the absence of water.
A method for increasing the amount of cenospheres in a fly ash sample, the method comprising:
- (a) providing an amount of fly ash having an initial percentage of cenospheres;
- (b) classifying the amount of fly ash into a first fraction of fly ash having particle densities greater than a predetermined particle density and a second fraction of fly ash having particle densities less than or equal to the predetermined particle density;
- and
- (c) separating the first fraction of fly ash or the second fraction of fly ash into a third fraction of fly ash having particle sizes less than or equal to a predetermined particle size and a fourth fraction of fly ash having particle sizes greater than the predetermined particle size such that the fourth fraction of fly ash has a percentage of cenospheres greater than the initial percentage,
- wherein the initial percentage of cenospheres and the percentage of cenospheres in the fourth fraction of fly ash are volume percentages or weight percentages, and
- wherein step (b) comprises classifying the amount of fly ash by density by air classification.
Dependencies are inferred from the claim text.