Abstract: Systems and methods for beneficiating a recovered fly ash material and/or recovering fly ash from an impound site are described. The method may include thermally treating a first portion of a recovered fly ash material to form a thermally treated fly ash having a first temperature of at least 1000° F., and contacting the thermally treated fly ash with a second portion of the recovered fly ash material to cool the thermally treated fly ash to a second temperature of less than or equal to 500° F. and form a fly ash product. The fly ash product may have a carbon content less than 8% by weight, based on the total dry weight of the fly ash product.

Abstract: Aggregates useful in building materials such as concrete are described. The aggregates may include fly ash and an inorganic polymer binder, which may be present as an outer layer on a core of fly ash. Methods of preparing the aggregates and concrete mixtures comprising the aggregates are also described. For example, the aggregates may be prepared by contacting fly ash agglomerates with an alkaline solution. The concrete mixtures may comprise the aggregates and a hydraulic cement.

Abstract: Systems and methods for beneficiating a recovered fly ash material and/or recovering fly ash from an impound site are described. The method may include thermally treating a first portion of a recovered fly ash material to form a thermally treated fly ash having a first temperature of at least 1000° F., and contacting the thermally treated fly ash with a second portion of the recovered fly ash material to cool the thermally treated fly ash to a second temperature of less than or equal to 500° F. and form a fly ash product. The fly ash product may have a carbon content less than 8% by weight, based on the total dry weight of the fly ash product.

Abstract: Systems and methods for beneficiating a recovered fly ash material and/or recovering fly ash from an impound site are described. The method may include thermally treating a first portion of a recovered fly ash material to form a thermally treated fly ash having a first temperature of at least 1000° F., and contacting the thermally treated fly ash with a second portion of the recovered fly ash material to cool the thermally treated fly ash to a second temperature of less than or equal to 500° F. and form a fly ash product. The fly ash product may have a carbon content less than 8% by weight, based on the total dry weight of the fly ash product.

Abstract: Aggregates useful in building materials such as concrete are described. The aggregates may include fly ash and an inorganic polymer binder, which may be present as an outer layer on a core of fly ash. Methods of preparing the aggregates and concrete mixtures comprising the aggregates are also described. For example, the aggregates may be prepared by contacting fly ash agglomerates with an alkaline solution. The concrete mixtures may comprise the aggregates and a hydraulic cement.

Abstract: Disclosed is a method for enhancing the performance of concrete includes, providing a cementitious mixture comprising cement and processed high calcium fly ash; wherein a processing of the processed high calcium fly ash neutralizes a cementitious reactivity of a high calcium fly ash, wherein a pozzolanic reactivity of the processed high calcium fly ash is maintained during the processing of the high calcium fly ash. The processing of the high calcium fly ash includes hydrating and carbonating the high calcium fly ash. The processing further includes excavating the high calcium fly ash from a landfill or surface impoundment after the hydrating and carbonating. Also disclosed is a portland-pozzolan blended cement mixture with clinker, gypsum, and a pozzolanic material, such as processed high calcium fly ash. After processing, the cementitious reactivity of a high calcium fly ash is neutralized, while pozzolanic reactivity of the high calcium fly ash is maintained.

Abstract: Disclosed is a method for enhancing the performance of concrete includes, providing a cementitious mixture comprising cement and processed high calcium fly ash; wherein a processing of the processed high calcium fly ash neutralizes a cementitious reactivity of a high calcium fly ash, wherein a pozzolanic reactivity of the processed high calcium fly ash is maintained during the processing of the high calcium fly ash. The processing of the high calcium fly ash includes hydrating and carbonating the high calcium fly ash. The processing further includes excavating the high calcium fly ash from a landfill or surface impoundment after the hydrating and carbonating. Also disclosed is a portland-pozzolan blended cement mixture with clinker, gypsum, and a pozzolanic material, such as processed high calcium fly ash. After processing, the cementitious reactivity of a high calcium fly ash is neutralized, while pozzolanic reactivity of the high calcium fly ash is maintained.

Abstract: A method and system for measuring the adsorption potential of fly ash. A sample of the fly ash is mixed with an optically active reagent. The mixture is irradiated with light at a given wavelength and an optical parameter of the irradiated sample, such as intensity of optical absorbance or fluorescence emission is measured by an optical measuring apparatus. The adsorption capacity of the sample is determined as a function of the optical measurement. A controller is provided that communicates with the optical absorption measuring apparatus and controls flow of fly ash and sacrificial agent to a reaction zone or housing wherein the fly ash is contacted by the sacrificial agent.

Abstract: A method and system for measuring the adsorption potential of fly ash. A sample of the fly ash is mixed with an optically active reagent. The mixture is irradiated with light at a given wavelength and an optical parameter of the irradiated sample, such as intensity of optical absorbance or fluorescence emission is measured by an optical measuring apparatus. The adsorption capacity of the sample is determined as a function of the optical measurement. The system comprises a controller that communicates with the optical absorption measuring apparatus and controls flow of fly ash and sacrificial agent to a reaction zone or housing wherein the fly ash is contacted by the sacrificial agent.

Abstract: A process is described that removes by chemical oxidation the excess ammonia (NH3) gas from flue gases that have been subjected to selective catalytic reduction (SCR) and selective non-catalytic reduction (SNCR) of oxides of nitrogen (NOx) by ammonia injection. Methods for the removal of residual ammonia from flue gases prior to fouling air pre-heaters or deposition on fly ash are discussed.

Abstract: The present invention relates to a pozzolanic admixture containing ammonia-laden fly ash, method for making the pozzolanic admixture and method for controlling ammonia gas (NH3) emission from cementitious slurries using the pozzolanic admixture. The associated hypochlorite and ammonia reaction produces monochloramine and chloride salts at relatively low concentration levels harmless to concrete and concrete applications. The resulting monochloramine and chloride salt products are stable and do not dissipate into the air, thereby, eliminating odorous emission that is produced from cementitious slurry containing untreated ammonia laden fly ash.

Abstract: The present invention relates to a pozzolanic admixture containing ammonia-laden fly ash, method for making the pozzolanic admixture and method for controlling ammonia gas (NH3) emission from cementitious slurries using the pozzolanic admixture. The associated hypochlorite and ammonia reaction produces monochloramine and chloride salts at relatively low concentration levels harmless to concrete and concrete applications. The resulting monochloramine and chloride salt products are stable and do not dissipate into the air, thereby, eliminating odorous emission that is produced from cementitious slurry containing untreated ammonia laden fly ash.

Abstract: A process is described that removes by oxidation the excess ammonia (NH3) gas from flue gases that have been subjected to selective catalytic reduction (SCR) and selective non-catalytic reduction (SNCR) of oxides of nitrogen (NOx) by ammonia injection. Methods for the removal of residual ammonia from flue gases prior to deposition on fly ash are discussed.

Abstract: Processes for treating fly ash to enhance the fly ash as a pozzolan for portland cement mixes and to separate therefrom a substantial carbon compound and/or to increase the fineness of the fly ash include the treatment of a fly ash slurry with ultrasonic energy using ultrasonic horns immersed in a slurry of fly ash and water and imparting to said slurry such ultrasonic energy as to cause microscopic cavities to form and implode with high localized energy to break up fly ash agglomerations along cleavage lines and to break up carbon particles and matrices which have entrapped fly ash microspheres therein to release the microspheres into the slurry. A conditioner agent may be added at or during ultrasonic treatment to enhance the flotation of the carbon compound.

Abstract: Processes for treating fly ash to enhance the fly ash as a pozzolan for portland cement mixes and to separate therefrom a substantial carbon compound and/or to increase the fineness of the fly ash include the treatment of a fly ash slurry with ultrasonic energy using ultrasonic horns immersed in a slurry of fly ash and water and imparting to said slurry such ultrasonic energy as to cause microscopic cavities to form and implode with high localized energy to break up fly ash agglomerations along cleavage lines and to break up carbon particles and matrices which have entrapped fly ash microspheres therein to release the microspheres into the slurry. A conditioner agent may be added at or during ultrasonic treatment to enhance the flotation of the carbon compound.