1. Duke Energy Coal Ash Beneficial Reuse Technologies Study
Presentation to the GWWMC
Raleigh, NC November 9, 2016

2. Coal Ash Beneficial Use Program
Duke Energy is committed to exploring safe and economic ways to recycle coal ash.
So far in 2016, the company has recycled more than 58% of the total production ash (total CCPs >80% reuse) that is produced at our coal plants. The CCPs are currently used in concrete, cement, structural fills, wallboard, agricultural, misc. products.
We’re committed to recycle as much material as we can, but this is driven by many factors including market demand and transportation costs. Ultimately, we seek to make investment and recycling decisions that benefit our customers.
Status of coal ash beneficiation technology study per the CAMA and HB-630

3. Overview of CAMA Section 4.(e) - Requirements
Coal Ash Management Act of 2014 / HB-630
Required study of CCP uses and markets
Submittal to EMC and the CAMC
August 1, 2016
Duke selected EPRI through RFP to conduct the “CAMA Study”
Project Scope Overview
Phase 1: Market Study
Phase 2: Beneficiation Technologies
Phase 3: Alternative and Innovative Technologies
Present findings of RFP per HB-630 Section 4.(e) to the EMC before 08/01/16.
Note: The reports were issued to Mr. Rowland, Chairman of EMC, on /18/16.

4. Duke Energy Coal Ash Beneficial Reuse
Technologies Study
Phase 1: Market Study

5. Market Drivers
Supply – Produced + stored; Must be reliable and consistent supply
Demand – Current and new uses
Transportation – Bulk material of low to moderate value; transportation costs have a large impact on value and marketability
Quality – Ash Characteristics (e.g. LOI, fineness, Ammonia / FGD/ other constituents, etc.) and Consistency of Supply.
Price – “Hurdle Rate” equals cost of disposal. New laws (CAMA, HB-630) & regulatory environment for disposal should incentivize more product options for beneficial reuse.
Regulatory/Public Perception Risk – Regulatory uncertainty and public perception influence market viability
Competition – Coal fired generation has significantly decreased, but impetus among utilities to use both produced and stored CCPs.

6. Operating Coal Fired Duke Plant Sites

7. Retired Duke Coal Fired Plant Sites
Buck
5.3 MT
Weatherspoon
1.5 MT
Dan River
2.8 MT
HF Lee
6.0 MT
Riverbend
4.9 MT
Sutton
7.2 MT
7 Inactive CCP Sites
64 CCP impoundments
34 MT Stored CCPs
Station
Stored Tons
Cape Fear
5.7 MT

8. Duke NC Coal Ash Market Map

9. Fly Ash Projections into Concrete Products Markets in NC
Estimated Maximum Annual Fly Ash Demand into Concrete Products
Estimated by
2015 to 2019
2020 to 2030
Duke
0.600
0.800
Leming (2015)
0.997
1.531

10. Duke NC - Coal Ash Quality
CCPs at most sites do not meet NCDOT or ASTM specs for use in concrete, primarily LOI
Belews Creek – Best quality and good sales in concrete markets
Roxboro Beneficiation – Electrostatic Separation
Limited Sales from other plants due to quality, consistency, or qty
Data on quality and consistency limited

11. Other Current Ash Use Markets in NC

12. Phase 2: Beneficiation Technologies
Duke Energy Coal Ash Beneficial Reuse
Technologies Study
Phase 2: Beneficiation Technologies

13. Options to feed Ready Mix Concrete Market
Dry Beneficiation
Selective Collection
Air Classification
Tribo-Electrostatic Separation
Thermal Technology (FBC)
Chemical Passivation
Wet Beneficiation
Thermal Beneficiation (SEFA STAR)
Ash Recovery
Froth Flotation
Screening
Hydraulic Separation

14. Tribo-electrostatic Separation
Tampa Electric Big Bend Power Plant
Longannet Power Plant
Examples:
Duke Roxboro Power Plant
Tampa Electric-Big Bend Station
South Mississippi EP -R.D. Morrow Plant
RWE npower-Aberthaw Station

15. Thermal Beneficiation
PMI
Dense Phase FBC
High Thermal Mass
Long Retention Time
Fluidizing gas = Combustion gas
LOI Limitations
Proven Track Record
SEFA
Dilute Phase FBC
Short Retention Time
Fluidizing gas ≠ Combustion gas
Can go to Zero LOI
Stand alone system
Operated on ponded ash
Proven Track Record
LOI
+++
Fineness +
Uniformity
Complexity
++++
Examples:
PMI Carbon Burn Out®
SEFA STAR®

16. Phase 3: Innovative Technologies
Duke Energy Coal Ash Beneficial Reuse
Technologies Study
Phase 3: Innovative Technologies

17. Alternative and Innovative Technologies
Objective
Identify, categorize, and describe alternative and innovative technologies and products for the use of coal ash.
Technologies that currently have limited or no commercial markets
Assess technology maturity and potential market
Approach
Literature and internet searches
Industry and vendor contacts
Papers and conferences and Academia
An Open Innovation Search process
Technologies grouped into broad categories to facilitate comparison.

18. Technology Grouping
Market Ready Technologies
Mature Technologies
Emerging Technologies
Technologies with current limited market potential

19. Limited current market
Market ready
Emerging
Mature
Limited current market
Flowable Fill
Cenospheres
Superpozzolans
Aggregates
Geopolymer
Masonry units
Alternative cement
Wastewater stabilization
Metal Composites
Proppants
Polymer composites
Autoclaved concrete
Zeolites
Metal Recovery
Rare earth recovery
Nanotechnology
Plasma vitrification

20. Limited current market
Market ready
Emerging
Mature
Limited current market
Flowable Fill
Cenospheres
Superpozzolans
Aggregates
Geopolymer
Masonry units
Alternative cement
Wastewater stabilization
Metal Composites
Proppants
Polymer composites
Autoclaved concrete
Zeolites
Metal Recovery
Rare earth recovery
Nanotechnology
Plasma vitrification
Colored ones have very limited acceptance in the US – or not cost competitive
High Value
Potential for large market

21. Recommendations for Beneficial Reuse
Know your ash
By unit and time: Due to changing coal supply, coal quality changes frequently, so testing by unit occurs on an as needed basis
Core ponds: Underway at Allen, Buck, Cape Fear, Cliffside, HF Lee, Mayo, Weatherspoon, others
Work with vendors to explore technologies / new products
Evaluate the viability of the ash technologies. Testing is cheap
HB-630: Mandate to install three (3) ash beneficiation units
Evaluating new product options: brick, block, pavers, aggregates, etc.
Submit RFP to better understand the markets
No panacea exist
Stay involved with our ash marketers to continually enhance market options

22. Thank You Any Questions???