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Coal Ash Beneficiation and

Recycle Options

Dale BradshawCEO Electrivation

dtbradshaw@electrivation.com423-238-4052Thanks to Timothy McDonald of APS

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National Coal Combustion By-Products (CCB) examples

Coal pile Pulverizer

Power Plant

Bottom Ash

Fly AshFGD Sludge

- Gypsum wallboard- Blended cement

- Portland cement- Cenospheres- Concrete products- Structural fills- Road base- Mining applications- Soil modification- Waste stabilization

- Road base

- Structural fill- Snow & ice control- Concrete products- Portland cement- Aggregate

~80%

~20%

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CCB Utilization

71.7 million tons fly ash produced nationally (2007 data) 18.1 Mtons bottom ash and 12.3 Mtons FGD gypsum 47% of ash and gypsum used in construction Dependent on local markets, hauling costs, economy Revised EPA rules for coal combustion byproducts

(CCB) expected by February-March 2010 CCB stigma if regulated as hazardous waste Expect impacts on handling, utilization, disposal options Beyond just utilization must consider ash material

Reduction, Conversion and Reclamation options

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Coal Pile Pulverizer

Methods to Reduce Coal

AshCoal Processing

Coal to Boiler

Magmill

Density Classifier

Reject inorganics & coal

Exothermic heat to Boiler

Supercritical Water

Carbon recovery Reactor

Pyrite,FeldsparQuartz,and OtherInorganics

( RED = New Equipment )

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Coal Processing Details

Magmill dry magnetic cleaning of pulverized coal w/ maximizedremoval of pyrite and other minerals

Techinomics Inc. - density classifier to remove ash Magmill and/or classifier will need carbon recovery Carbon Recovery Alternatives:

Supercritical water conversion of carbon w/ heat recovery Separation Technologies (ST) Inc. extraction process

Electrostatic concentration and recovery of carbon from ash Concentrated carbon recycled as boiler fuel input

PMI Ash Technologies LLC carbon burn-out technology Eliminate carbon in remaining inorganic ash material

Cleaned ash / ore suitable for Mining Exothermic heat recovery to plant

Carbon recovery may be required with either coal cleaningtechnology as appropriate. Both cleaning technologies may berequired to maximize this ash Reduction option.

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Magmill

Dry magnetic cleaning ofpulverized coal

APS power plant coal

tested at Magmill pilot site Reduce Ash, SO2, Hg

Improve power plantperformance & reliability

Carbon recovery to plant Mining ash concentrate

Plant demo(s) ??

Magmill System

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Techinomics Density Classifier

Rotating throat-ledgecover system

Demonstration at Gavin

power plant AEP Pyretic rock is efficiently

removed from pulverizer

Increased primary air

velocity but not flow mass Improved coal finenessand boiler combustion

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Coal Ash Conversion Option Using RussianHydroalkaline process with ST magnetic separator

Coal Ash MiningFly Ash

Silo

ST magneticseparator

Carbon to Boiler

[FLY] ASH

Activation Magnetic Separation

Fe2O3 - Concentrate

Hydroalkaline

Silica Extraction

Alumina Concentrate

Alloys

Refractories

Building

materials

AluminaProduction

Alumina

Mud

Portland Cement

Silicate Alkaline Solution

Regeneration

Process into Pure Silicate Products:

Silicates, Silica, Zeolites, White

Soot, Glass Components,

Ceramics, Cement, [Aerogel]

and Other

Figure 4. Flow Sheet for alumina, silicaand iron recovery from ash

variant operations

Ash beneficiation

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Coal Ash Mining

Coal Fly Ash Processing into Metallurgical and SilicateChemical Products:

Russian HYDROALKALINE pilot process w/ magneticrecovery of concentrated Fe2O3

Ferric-oxide recovery approx 50%

Hydroalkaline silica extraction approx 60%-77% Bauxite quality Alumina ash remaining for processing Alumina production residue mud is considered a

valuable Portland cement additiveAsh Beneficiation Alternatives: (see Coal Processing) Separation Technologies (ST) process separates carbon

from fly ash w/ carbon recycled back to boiler PMI Ash Technologies carbon burn-out technology w/

heat recovery back to boiler

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RockTron Eco-Minerals

RockTron is a UK company; http://rktron.com

Fiddlers Ferry eco-mineral processing plant is on-line

Designed to process 800,000 tons of fly ash per year

Processes both fresh and stockpiled ash (ash pond?) RockTron eco-mineral coal-ash products:

Alpha and delta cement additive pozzolanic glass spheres

90% purity carbon

Cenospheres Spherical magnetite

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RockTron Eco=Mineral

Reclamation Process RockTron eco-mineral recycling ofash ponds(?)

Replacement w/ lined ash ponds andenhanced dams

Dewatering bags within lined basins

Convert de-watered pond ash intoGeopolymer Concrete for enhancedstructures and/or products

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FLYASH MINING

Collaboration Opportunities Nalco Mobotec: Magmill concentrate

EERC, Univ. ofNorth Dakota: Coal Ash Research Center

BHP Billiton: Four Corners plant coal supplier University of Wisconsin, Madison: Center for By ProductsUtilization

Lyntek Inc., Denver Co

Pittsburgh Mineral & Mining Technology Inc. University of Arizona, Chemical Engineering and MaterialSciences Departments

Others

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Keystone Metals Recovery, IncProcess for recovering Metals from Coal Ash

The coal ash is heated in a CFBC using coal and the carbon in theash (LOI) to break the physical bonds of the metals in the ash withthe waste heat used for a small T/G or used to by-pass feedwaterheaters in the plant.

The ash is chlorinated with the metal chloride gases (Al, Ti, Fe, and

others) removed from the remaining solids (Silicon oxide) in cycloneseparators. Coal ash has the following: 50% to 55% sand 22% to 35% Al 3% to 10% Fe 1% to 1.5% Ti Trace quantities of germanium, gallium, Hg, etc.

The metal chlorides are reduced to molten metals and formed intoingots for sale. (electricity used to produce the Al from the chloride is65% less than production from bauxite). Ball

The remaining sand can be stacked on site or sold.

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Keystone Metals Recovery, IncProcess for recovering Metals from Coal Ash

Keystone has successfully tested thechlorination and recovery steps in the lab

Keystone is attempting to secure $30 million for

a 50 tpd pilot plant and has a $5 millioncommitment from Ball canning and will generateexcess electricity for the grid and have a profit of$2 million per year.

Keystone would then scale up to a 1,000 tpdplant which would cost about $200 million to$250 million and would generate a pre-taxoperating profit of $72 million from the Al and theTi sales only.

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Keystone Metals Recoveryto chlorinate ash and recover valuable AL, Ti, Fe, and other heavy metals.