Ponded ash beneficiation system and related methods

1. A process for beneficiating landfilled or ponded waste coal fly ash the process comprising:

forming a waste coal fly ash stream having greater than 2% LOI of carbon from waste coal fly ash collected at ambient temperature from a pond or landfill;

subjecting the waste coal fly ash stream to elevated temperatures sufficiently above the ambient temperature to remove at least 75% of the carbon from the waste coal fly ash, the elevated temperature predetermined as a function of at least one of the following characteristics of the collected waste coal fly ash: moisture, LOI, and particle size;

exposing the waste coal fly ash stream to an oxygen-rich atmosphere by introduction of additional air, while subjecting the waste coal fly ash stream to the elevated temperature, the oxygen-rich atmosphere predetermined as a function of at least one of the following characteristics of the collected waste coal fly ash: LOI, hydrolysis, and available carbonates; and

performing the steps of subjecting the waste coal fly ash stream to the predetermined elevated temperature and to the predetermined oxygen-rich atmosphere for a processing time predetermined to reduce the LOI of the waste coal fly ash to 2% or less, thereby forming a beneficiated coal fly ash,

wherein the waste coal fly ash comprises oxidized ash characterized by having coarse waste coal fly ash particles having sizes ranging from 50-635 microns, and wherein the process comprises reducing the coarse waste coal fly ash particle size by 95% during the exposing of the waste coal fly ash stream to heat, and subsequently separating and continually recirculating the coarse waste coal ash particles after the exposure to the heat to form a beneficiated coal fly ash characterized by a minimum of 66% of the beneficiated coal fly ash particles passing through a 44 micron screen.

2. The process of claim 1 , wherein the collecting step comprises creating a stockpile of landfilled or ponded waste coal fly ash with a moisture content ranging from 3% to 40%, and further comprising the steps of reducing the moisture by application of heat in advance of particle size reduction.

3. The process of claim 1 , further comprising the step of inserting the waste coal fly ash stream into a moisture reduction vessel prior to the step of exposing the waste coal fly ash stream to the oxygen-rich environment to form a dried waste coal fly ash.

4. The process of claim 3 , further comprising the step of inserting the dried waste coal fly ash into a vibratory screen after the step of inserting the waste coal fly ash stream into the moisture reduction vessel.

5. The process of claim 1 , further comprising the steps of testing and homogenizing the waste coal fly ash stream after collection thereof.

6. A process for beneficiating landfilled or ponded waste coal fly ash the process comprising:

forming a waste coal fly ash stream having greater than 2% LOI of carbon from waste coal fly ash collected at ambient temperature from a pond or landfill;

subjecting the waste coal fly ash stream to elevated temperatures sufficiently above the ambient temperature to remove at least 75% of the carbon from the waste coal fly ash, the elevated temperature predetermined as a function of at least one of the following characteristics of the collected waste coal fly ash: moisture, LOI, and particle size;

exposing the waste coal fly ash stream to an oxygen-rich atmosphere by introduction of additional air, while subjecting the waste coal fly ash stream to the elevated temperature, the oxygen-rich atmosphere predetermined as a function of at least one of the following characteristics of the collected waste coal fly ash: LOI, hydrolysis, and available carbonates;

performing the steps of subjecting the waste coal fly ash stream to the predetermined elevated temperature and to the predetermined oxygen-rich atmosphere for a processing time predetermined to reduce the LOI of the waste coal fly ash to 2% or less, thereby forming a beneficiated coal fly ash; and

providing for internal cascade flow of the waste coal fly ash against a carbon reduction kiln shell to facilitate increased exposure to oxygen during the selected range of the processing time,

wherein the waste coal fly ash comprises oxidized ash characterized by having coarse waste coal fly ash particles having sizes ranging from 50-635 microns, and wherein the process comprises reducing the coarse waste coal fly ash particle size by 95% during the exposing of the waste coal fly ash stream to heat, and subsequently separating and continually recirculating the coarse waste coal ash particles after the exposure to the heat to form a beneficiated coal fly ash characterized by a minimum of 66% of the beneficiated coal fly ash particles passing through a 44 micron screen.

7. A process for beneficiating landfilled or ponded waste coal fly ash the process comprising:

forming a waste coal fly ash stream having greater than 2% LOI of carbon from waste coal fly ash collected at ambient temperature from a pond or landfill;

subjecting the waste coal fly ash stream to elevated temperatures sufficiently above the ambient temperature to remove at least 75% of the carbon from the waste coal fly ash, the elevated temperature predetermined as a function of at least one of the following characteristics of the collected waste coal fly ash: moisture, LOI, and particle size;

inserting the waste coal fly ash stream into a moisture reduction vessel;

inserting the dried waste coal fly ash into a vibratory screen;

inserting the dried and screened waste coal fly ash into a system adapted to reduce particle size and oxidation of the beneficiated coal fly ash;

exposing the waste coal fly ash stream to an oxygen-rich atmosphere by introduction of additional air, while subjecting the waste coal fly ash stream to the elevated temperature, the oxygen-rich atmosphere predetermined as a function of at least one of the following characteristics of the collected waste coal fly ash: LOI, hydrolysis, and available carbonates; and

performing the steps of subjecting the waste coal fly ash stream to the predetermined elevated temperature and to the predetermined oxygen-rich atmosphere for a processing time predetermined to reduce the LOI of the waste coal fly ash to 2% or less, thereby forming a beneficiated coal fly ash,

wherein the waste coal fly ash comprises oxidized ash characterized by having coarse waste coal fly ash particles having sizes ranging from 50-635 microns, and wherein the process comprises reducing the coarse waste coal fly ash particle size by 95% during the exposing of the waste coal fly ash stream to heat, and subsequently separating and continually recirculating the coarse waste coal ash particles after the exposure to the heat to form a beneficiated coal fly ash characterized by a minimum of 66% of the beneficiated coal fly ash particles passing through a 44 micron screen.

8. A process for beneficiating landfilled or ponded waste coal fly ash the process comprising:

forming a waste coal fly ash stream having greater than 2% LOI of carbon from waste coal fly ash collected at ambient temperature from a pond or landfill;

subjecting the waste coal fly ash stream to elevated temperatures sufficiently above the ambient temperature to remove at least 75% of the carbon from the waste coal fly ash, the elevated temperature predetermined as a function of at least one of the following characteristics of the collected waste coal fly ash: moisture, LOI, and particle size;

inserting the waste coal fly ash stream into a moisture reduction vessel to form a dried waste coal fly ash, wherein the moisture reduction vessel is selected from the group consisting of a dryer and an aero acoustic machine;

exposing the dried waste coal fly ash stream to an oxygen-rich atmosphere by introduction of additional air, while subjecting the waste coal fly ash stream to the elevated temperature, the oxygen-rich atmosphere predetermined as a function of at least one of the following characteristics of the collected waste coal fly ash: LOI, hydrolysis, and available carbonates; and

performing the steps of subjecting the waste coal fly ash stream to the predetermined elevated temperature and to the predetermined oxygen-rich atmosphere for a processing time predetermined to reduce the LOI of the waste coal fly ash to 2% or less, thereby forming a beneficiated coal fly ash.

9. A process for beneficiating landfilled or ponded waste coal fly ash the process comprising:

forming a waste coal fly ash stream having greater than 2% LOI of carbon from waste coal fly ash collected at ambient temperature from a pond or landfill;

subjecting the waste coal fly ash stream to elevated temperatures sufficiently above the ambient temperature to remove at least 75% of the carbon from the waste coal fly ash, the elevated temperature predetermined as a function of at least one of the following characteristics of the collected waste coal fly ash: moisture, LOI, and particle size;

exposing the waste coal fly ash stream to an oxygen-rich atmosphere by introduction of additional air, while subjecting the waste coal fly ash stream to the elevated temperature, the oxygen-rich atmosphere predetermined as a function of at least one of the following characteristics of the collected waste coal fly ash: LOI, hydrolysis, and available carbonates; and

performing the steps of subjecting the waste coal fly ash stream to the predetermined elevated temperature and to the predetermined oxygen-rich atmosphere for a processing time predetermined to reduce the LOI of the waste coal fly ash to 2% or less, thereby forming a beneficiated coal fly ash,

wherein the waste coal fly ash comprises oxidized ash characterized by having coarse waste coal fly ash particles having sizes ranging from 50-635 microns, and wherein the process comprises reducing the coarse waste coal fly ash particle size by 95% during the exposing of the waste coal fly ash stream to heat, and subsequently separating and continually recirculating the coarse waste coal ash particles after the exposure to the heat to form a beneficiated coal fly ash characterized by a minimum of 66% of the beneficiated coal fly ash particles passing through a 44 micron screen,

wherein the elevated temperature is between 900° F. and 1150° F.