The Future of Coal Byproduct
Utilization
Dr. Jack Groppo
University of Kentucky
Center for Applied Energy Research
Lexington, Kentucky
Outline
• Production and Utilization
– Fly Ash, Bottom Ash and Boiler Slag
– Flue Gas Desulfurization Products
• Production and Utilization Projections
• Impact of Biomass
• CAER Byproduct Utilization Research Program
• Impact of Regulation Reclassification
0
2
4
6
8
10
12
14
16
18
20
0
200
400
600
800
1,000
1,200
1,400
1,600
1,800
2,000
Co
al
Qu
ali
ty,
% A
sh
Th
ou
san
d T
on
s
Coal Consumption*
Ash Production**
Ash Content
* Electrical Generation
** Fly Ash, Bottom Ash and Boiler Slag
0
10
20
30
40
50
60
70
80
90
100
Total Class F Class C
Mil
lion
ton
s
Sold
Offsite
Onsite
Ponds
Landfill
Ash Disposal Practice, 2005
Source: 2005 EIA-767
Fly Ash, Bottom Ash and Boiler Slag
0
10
20
30
40
50
60
0
10
20
30
40
50
60
70
80
90
100
2000 2001 2002 2003 2004 2005 2006 2007 2008 2009
Uti
liza
tion
Rate
, %
Pro
du
ctio
n a
nd
Uti
liza
tion
, M
illi
on
ton
s
Production
Utilization
% Utilization
Fly Ash and Bottom Ash
-
2,000
4,000
6,000
8,000
10,000
12,000
14,000
16,000
18,000
Th
ou
san
d t
on
s
2001
2005
2008
FGD Byproducts
-
1,000
2,000
3,000
4,000
5,000
6,000
7,000
8,000
9,000
Th
ou
san
d t
on
s
2001
2005
2008
FGD Gypsum
0
10
20
30
40
50
60
70
80
90
-
2
4
6
8
10
12
14
16
18
20
2001 2002 2003 2004 2005 2006 2007 2008 2009
Uti
liza
tion
, %
Pro
du
ctio
n a
nd
Uti
liza
tion
, M
illi
on
ton
s
Production
Utilization
Utilization Rate
All FGD Byproducts
0
5
10
15
20
25
30
35
40
45
50
2002 2003 2004 2005 2006 2007 2008
Mil
lio
n T
on
s
Production
FBC Ash
FGD Other
FGD Dry Scrubber
FGD Wet Scrubber
FGD Gypsum
0
5
10
15
20
25
30
35
40
45
50
2002 2003 2004 2005 2006 2007 2008
Mil
lio
n T
on
s
Utilization
FBC Ash
FGD Other
FGD Dry Scrubber
FGD Wet Scrubber
FGD Gypsum
Portland Cement and Ash Consumption
0
5
10
15
20
25
30
0
20
40
60
80
100
120
140
160
Ash
Use
d i
n C
emen
t A
pp
lica
tion
s, M
illi
on
ton
s
Ap
para
ent
Port
lan
d C
emen
t C
on
sum
pti
on
, M
illi
on
ton
s
Projections
Units 2008 2013
Coal Consumption, electric Million Tons 1043.6 1126.6
Byproduct Production Million Tons 136.1 165.6
Byproduct Utilization Million Tons 60.6 62.0
Utilization Rate % 44.5 37.4
Byproduct production will Increase by 22%
Ash production will increase by 8%
Ash will have higher C (Low NOx Burners and ACI)
FGD will increase by 58%
5 Year Projections
0
20
40
60
80
100
120
140
160
180
200
Coal Consumption Byproduct Production Byproduct Utilization Utilization Rate
Mil
lion
Ton
s or
%
2008
2013
1043.6
1126.6
0
20
40
60
80
100
120
2008 2013 2008 2013 2008 2013
Mil
lion
Ton
s
FBC Ash
FGD Other
FGD Dry Scrubber
FGD Wet Scrubber
FGD Gypsum
Boiler Slag
Bottom Ash
Fly Ash
Ash FGD FBC
0
5
10
15
20
25
30
35
40
45
2008 2013 2008 2013 2008 2013M
illi
on
Ton
s
Ash FGD FBC
Production Utilization
Impact of Biomass on Ash Quality
Fuel Variety C H N S VM FC AshHHV,
Btu/# dry
Black Locust Robinia pseudoacacia 50.4 5.7 0.54 0.03 77.7 21.10 2.08 8,418
American Sycamore Platanus occidentalis 49.7 6.2 0.25 0.03 80.8 18.06 1.24 8,414
Eucalyptus Saligna 49.9 5.9 0.06 0.01 81.2 17.20 1.22 8,384
Corn Stover Zea mays 47.0 5.5 0.68 0.06 73.1 22.00 10.24 7,967
Sugarcane Bagasse Gramineae Saccharum 48.4 6.0 0.17 0.02 79.4 17.88 3.66 8,349
Switchgrass Alamo 47.3 5.3 0.51 0.01 73.8 21.57 5.76 7,998
Sericea Lespedeza Serala 48.8 5.5 1.03 0.07 76.4 21.54 2.89 8,341
Monterey Pine Pinus Radiata 50.3 6.0 0.03 0.01 80.5 19.35 0.30 8,422
Eastern Cottonwood Populus Deltoides 49.7 5.9 0.08 0.05 79.2 20.06 1.00 8,431
MSW 37.2 4.9 0.60 0.20 70.0 10.00 24.00 5,865
Bituminous Coal Pittsburgh Seam 75.0 5.0 1.50 2.30 37.60 52.9 7.00 13,000
Subbituminous Coal Wyodak Seam 67.8 4.6 1.00 0.24 44.70 46.5 5.25 8,800
Biomass Composition
Source: USDoE Energy Efficiency & Renewable Energy
Biomass Feedstock Composition & Property Database
Parameter Test 1 2 3 4ASTM C-618 Spec
(Class C)
Switchgrass/Coal Ratio 0/100 5/100 5/100 5/100 -
Fineness % 14.8 17.1 16.8 17.3 < 34.0
LOI % 0.35 0.42 0.37 0.37 <6.0
Density g/cm3 2.72 2.65 2.66 2.64 -
SiO2 % 35.45 34.91 35.48 35.61 -
Al2O3 % 19.20 19.50 19.82 20.00 -
Fe2O3 % 5.35 5.04 4.96 4.99 -
SiO2+Al2O3+Fe2O3 % 60.00 59.45 60.25 60.59 >50.0
SO3 % 2.08 2.59 2.41 2.39 <5 .0
CaO % 26.41 25.39 24.82 24.52 -
7 day SAI % of Control 96 89 88 91 >75
28 day SAI % of Control 97 101 99 104 > 75
Water Requirement % of Control 95 95 95 95 <105
Autoclave Expansion % 0.06 0.06 0.07 0.06 <0.8
Sulfate Resistance
@6 months
20% Ash 0.034 0.035 0.033 0.034<0.05% for
High Resistance
36% Ash 0.039 0.036 0.036 0.032<0.10% for
Moderate Resistance
ASR Expansion@14 days20% Ash 136 146 150 114 <100% of Control
36% Ash 87 106 102 118 <100% of Control
Ottumwa Generating Station, IA Co-Combustion Ash: Silo Samples
http://iowaswitchgrass.com/__docs/pdf/Final%20Fly%20Ash%20Test%20Report.pdf
CAER Byproduct Utilization
Research Program
Ash Pond Sampling and
Characterization
Pond Sampling Techniques
Mechanical Auger
Hand Auger
Shovel and Bucket
Vibracoring
40 feet
(12.2m)
Pond Characterization
Beneficiation
Product Development
Super-Pozzolanic Additives (UFA)
0
20
40
60
80
100
120
140
0 7 14 21 28
Curing Time, days
5%
15%
25%
35%
SA
I, %
of
Co
ntr
ol
0
20
40
60
80
100
120
140
160
0 14 28 42 56 70 84 98 112 126Curing Time, days
Trimble
Rockport
Ghent 6/15 UFA
Ghent 6/21 UFA
Ghent 12/18 UFA
Ghent 1/27 UFA
SA
I, %
of
Co
ntr
ol
Fillers and Composites
60% UFA in HDPE 50% UFA in Santoprene (TPE)
Metal Matrix Composites of Aluminum with Ash
High Value Application Engineered Material
MMC improved Over Native MaterialStifferHarderMore Durable
Reduced Energy
Urethane Ash Composites
Combustion Tests of Ash Composites
Polyurethane Control
47.5% mass loss
50% UFA-Polyurethane
12.5% mass loss
Low Energy/Low CO2 Cements
Cement Type
CCBs Used
(% of Raw
Feed)
CO2 from
Raw Materials
(kg/ton
cement)
Ordinary Portland
Cement (OPC)~12 525
OPC w/20% Fly Ash
Replacement24-25 420
CAER CSAB
Formulation27.6 330
CAER CSA Formulation 40.2 173
CAER CSA Formulation
w/Fly Ash Interground50.4 138
•Gypsum Based Cements
•CSAB produced from
•Limestone, bauxite & gypsum
•Can also utilize
FGD gypsum
CFBC spent bed ash
•Can be Very Hard &
Fast Setting
•Low CO2 Emitting
Clinkerless Cement
Mainly produced from Class C fly ash and/or Clean
Coal Technology byproducts such as FBC ash
Cementitious reactions are mainly ettringite- and
pozzolan-based
Although strength gain is usually slow, these
materials can eventually become quite strong:
Clinkerless
Product
Unconfined Compressive Strength (PSI)
7 Day 28 Day 56 Day 112 Day
High W:C 205 887 1251 1506
Low W:C 490 1799 2487 3692
Consumer ProductsProduct Trade Name Company Description CCB
Component
CCB
Content
Lumber Life Time Lumber Century Products Decking Fly ash 65%
Substiwood Substiwood Fencing Fly ash 40%
Carpet Powerbond Collins & Aikmen Recycled carpet Fly ash 8%
Ceiling Tile Serene, Celotone BPB America Acoustic tile FGD Gypsum 48-92%
Floor Tile Various Florida Tile Floor Tiles Fly ash Varies
Masonry Featherlite Acme Brick Structural block Fly ash Varies
Substiwood Substiwood Pavers, edging Fly ash 40%
Enviro-Bricks Env. Construction Tech. Bricks, Blocks Fly ash 20-40%
Quikrete Quikrete Packaged concrete Bottom ash 30-60%
Paint Various Pruett-Schaffer Marine paints Fly ash Varies
Roofing Brikshake Midway Environmental Roofing Tiles Fly ash Varies
Black Beauty Reed Minerals Roofing granules Boiler slag 100%
Recreation Ebonite Ebonite Int’l Bowling Balls Cenospheres 40%
Appliances Various General Electric Insulation Fly ash 30-70%
Partitions Preform Preform Mfg. Partition systems FGD Gypsum Varies
Wallboard Densgard Georgia Pacific Walllboard FGD Gypsum 100%
Various LaFarge Wallboard FGD Gypsum 100%
ProRoc BPB America Wallboard FGD Gypsum 100%
Source: www.undeerc.org/carrc/BuyersGuide
Benefits of CCP Use That Are at Risk if CCPs Are
Designated a Hazardous Waste
Resource UnitsAnnual
SavingsEquivalent to
Energy trillion Btu 159·Annual energy use of 1.7 million households
·47% of annual wind power generation in the US
Water billion gal 32 ·31% of domestic water withdrawals of CA in 2000
CO2 equiv. million tons 11 ·Removal of 1.9 million cars from roadways
Financial billion $ 5.1-9.7 ·Annual full-time salary of 130,000-240,000 avg. Americans
Source: Ken Ladwig, “EPRI Research Activities”
ACAA Fall Meeting, Sept. 23, 2009.
Economic Benefits of CCP Utilization
Benefit Annual Amount
Revenue from the Sale of CCPs for Utilization $ 1.03 billion
Avoided Costs of Disposal $ 4.13 million
Savings from Use as Sustainable Building Materials $ 5 billion to $ 10 billion
Total Economic Impact $6.4 billion to $11.4 billion
Source: “The Value of Coal Combustion Products: An Economic
Assessment of CCP Utilization in the US Economy”,
American Coal Council.