Transcript Document

Shingles Recycling
A presentation by Dan Krivit at the
49th Annual Wisconsin
Asphalt Paving Conference
In Waukesha, Wisconsin
Wednesday, November 15, 2006
Definitions
• Manufacturers’ Asphalt Shingle Scrap
• Tear-Off Asphalt Shingle Scrap
• Recycled Asphalt Shingles (RAS)
(Crushed & screened)
History
• 15 years +
• Multiple research studies in lab and field
• Manufacturer shingle scrap in hot-mix
asphalt best known, most accepted
practice
• Still relatively new application
Key Barriers
• Lack of clear industry standards and
specifications
• Inconsistent state regulations
• Lack of adequate information /
technology transfer
• Lack of national leadership by private
industry and government
$400
New Jersey DOT Asphalt Cement Price Index
$350
$ per ton (English)
$300
$250
$200
$150
$100
$50
$0
J-90
J-91
J-92
J-93
J-94
J-95
J-96
J-97
J-98
J-99
J-00
Month (as of June 1 each year)
J-01
J-02
J-03
J-04
J-05
J-06
Composition of Residential
Asphalt Shingles
Recent Composition: Weight Ranges
of Typical Asphalt Shingles
• 32 to 42% Coating filler (limestone or fly ash)
• 28 to 42% Granules (painted rocks & coal slag)
• 16 to 25% Asphalt
• 3 to 6% Back dust (limestone or silica sand)
• 2 to 15% Mat (fiberglass, paper, cotton rags)
• 0.2 to 2% Adhesives (modified asphalt based)
Multiple Applications
• Hot mix asphalt (HMA)
• Aggregate / gravel
• Dust control
• Cold patch
• Ground cover
• Fuel
• New shingles
Factors Affecting
HMA Performance
• Aggregate gradation of RAS
• Properties of final blended binder content
within the HMA as affected by:
– RAS asphalt binder
– Virgin binder
Factors Affecting
HMA Performance (continued)
• Location RAS is incorporated
into HMA drum
• Temperature
• Moisture content of RAS and
other aggregates
• Retention time in HMA drum
Potential Benefits
• Rutting resistance (especially at
warmer temperatures)
• Conservation of landfill space
• Economic savings to HMA producer
due to reduced need for virgin
asphalt binder (add oil)
Potential Disadvantages
• Contamination (tear-offs)
• Added costs of processing and
use in HMA
• Increased low-temperature /
fatigue cracking
Performance Grading (PG)
Asphalt Grades
• PG 64-22
(“PG sixty-four minus twenty-two”)
• High temperature for rut resistance
64°C (147°F)
• Low temperature for fatigue and
cold weather performance
(e.g., cracking) -22°C (-8°F)
Mitigating Low Temperature
Impacts of RAS
• Use less RAS instead of 5%
(e.g., use 2% to 3%)
• Adjust the virgin binder PG to
one grade softer (e.g., PG 52-34)
Deleterious Material
•
•
•
•
•
•
•
Nails
Other metal
Wood
Cellophane
Other plastic
Paper
Fiber board
U of MN Research
• Professor Mihai Marasteanu
Dept. of Civil Engineering
Asphalt Lab
• Adam Zofka
Graduate Student
Missouri HMA Samples
• Two recycled sources:
– Tear-off shingles (5%)
– Recycled asphalt pavement (20%)
• Two virgin binders performance grades:
– PG 64-22
– PG 58-28
Marasteanu, July 2006
Creep Stiffness (MO: PG 64-22)
40
34.7
Stiffness @ 100sec
34.4
30
20% RAP
PG 64-22
19.5
20
10.8
10
15% RAP
5% shing.
PG 64-22
12.0
9.5
0
-10C
-20C
-30C
Marasteanu, July 2006
Creep Stiffness (MO: PG 64-22)
40
Stiffness @ 500sec
30.3
30
27.5
20% RAP
PG 64-22
20
10
16.4
7.4
8.9
15% RAP
5% shing.
PG 64-22
5.9
0
-10C
-20C
-30C
Marasteanu, July 2006
Marasteanu, July 2006
Creep Stiffness (MO: PG 58-28)
30
Stiffness @ 100sec
21.4
20
16.6
17.3
15% RAP
5% shing.
PG 58-28
11.5
10
20% RAP
PG 58-28
8.1
6.1
0
-10C
-20C
-30C
Marasteanu, July 2006
Creep Stiffness (MO: PG 58-28)
Stiffness @ 500sec
30
20
15.3 15.9
12.9
10
20% RAP
PG 58-28
15% RAP
5% shing.
PG 58-28
7.8
5.7
4.0
0
-10C
-20C
-30C
Marasteanu, July 2006
Strength (MO: PG 64-22)
6
Tensile Strength [MPa]
4.5
4.7
4.9
4.3
4.2
3.9
3
20% RAP
PG 64-22
15% RAP
5% shing.
PG 64-22
0
-10C
-20C
-30C
Marasteanu,
Marasteanu, July
July 2006
2006
Strength (MO: PG 58-28)
Tensile Strength [MPa]
6
4.4
4.5
4.5
4.4
4.5
4.1
20% RAP
PG 58-28
3
15% RAP
5% shing.
PG 58-28
0
-10C
-20C
-30C
Marasteanu, July 2006
Conclusions: Stiffness
(MO: At temperatures below -10°C)
• PG -22 mixture: addition of
shingles increases the mixture
stiffness considerably (a)
• PG -28 mixture: stiffness
difference lessened (b)
Marasteanu, July 2006
Conclusions: Strength
(MO: At temperatures below -10°C)
No significant affects due to shingles
for either PG -22 or PG -28 mixtures
Marasteanu, July 2006
Minnesota HMA Samples
• Three types of recycled materials
– 20% reclaimed asphalt pavement (RAP),
– 15% RAP + 5% Tear-off recycled asphalt shingles
(RAS),
– 15% RAP + 5% Manufactured RAS.
• Only one virgin asphalt binder: PG 58-28
Marasteanu, July 2006
Creep Stiffness (MN: PG 58-28)
(@ 100 seconds)
16
13.5
20% RAP
15% RAP + 5% Tear-off
12
15% RAP + 5% Manufactured
Stiffness [GPa]
10.0
8.2
8
5.0
4
5.5
2.7
0.2
0.5
0.2
0
0
-10
Temperature [ oC]
-20
Marasteanu, July 2006
Creep Stiffness (MN: PG 58-28)
(@ 500 seconds)
16
20% RAP
15% RAP + 5% Tear-off
Stiffness [GPa]
12
15% RAP + 5% Manufactured
8.7
8
5.6
4
2.3
5.3
2.7
1.1
0.1
0.2
0.1
0
0
-10
Temperature [ oC]
-20
Marasteanu, July 2006
Strength (MN: PG 58-28)
6.0
20% RAP
5.3
15% RAP + 5% Tear-off
Tensile Strength [MPa]
15% RAP + 5% Manufactured
4.8
4.6
4.5
5.1
4.5
4.0
3.2
3.2
2.9
2.0
0.0
0
-10
Temperature [ oC]
-20
Marasteanu, July 2006
Creep Stiffness (MO vs. MN)
(@ 100 seconds)
20
20% RAP - MO
16
16.6
20% RAP - MN
Stiffness [GPa]
15% RAP + 5% Tear-off - MO
15% RAP + 5% Tear-off - MN
12
13.5
11.5
10.0
8.1
8
6.1
5.0
4
2.7
0
-10C
-20C
Temperature [o C]
Marasteanu, July 2006
Creep Stiffness (MO vs. MN)
(@ 500 seconds)
20
20% RAP - MO
16
20% RAP - MN
Stiffness [GPa]
15% RAP + 5% Tear-off - MO
12.9
15% RAP + 5% Tear-off - MN
12
8.7
7.8
8
5.7
5.6
4.0
4
2.3
1.1
0
-10C
-20C
Temperature [o C]
Marasteanu, July 2006
Conclusions: Stiffness (MN)
• Adding tear-offs significantly
increases stiffness of the mixtures at
all test temperatures (a)
• Adding manufactured increases
stiffness only at 0°C and -10°C (b)
Marasteanu, July 2006
Conclusions: Strength (MN)
No significant affects due to either
tear-off or manufacturers’ shingles
scrap
Marasteanu, July 2006
Conclusions: Stiffness
(MO vs. MN)
• Lower stiffness values for the
Minnesota RAP mixtures compared
to Missouri mixtures
• Lower stiffness values for the MN
combinations of RAP + RAS
compared to MO mixtures (a)
Marasteanu, July 2006
Minnesota Extracted
Binder Samples
• Bending Beam Rheometer
(a)
(BBR)
• Direct Tension Tests
(b)
(DTT)
Marasteanu, July 2006
BBR (MN)
Marasteanu, July 2006
BBR Conclusions (continued)
• Addition of shingles changes the
properties (a)
• The two types of shingles perform
differently
– The manufactured material seems to be
beneficial (b)
– The tear-off material affects properties in a
negative way (although it also decreases
BBR stiffness) (c)
Marasteanu, July 2006
BBR Conclusions (continued)
• m-value not fully understood (a)
• The limited data also shows that
binder and mixture results do not
always agree (b)
• Need further research (c)
Marasteanu, July 2006
Mn/DOT Research
• Jim McGraw,
Director
Mn/DOT Chemistry Lab
%AC
Shingle Asphalt Content
45.0
40.0
35.0
30.0
25.0
20.0
15.0
10.0
5.0
0.0
Manufacture Waste
Demcon Tear-Off
RAP
1
2
3
4
5
6
7
8
9 10
Sample
McGraw, July 2006
AC Impact in Final Mix
(at 5% RAS)
• RAS binder addition:
–Manufacturers’ adds 1.0% binder
–Tear-offs adds 1.8%
McGraw, July 2006
Shingles Low PG Temp
15.0
PG Temp
10.0
5.0
0.0
1
2
3
4
5
6
7
-5.0
-10.0
-15.0
Sample
McGraw, July 2006
MW- TTS
TO-TTS
8
9
10
Final Hot Mix Low
Temperature PG (a)
• Tear-off -28.8 (b)
• Manufacturers’ -26.2 (c)
• RAP -29.2 (d)
McGraw, July 2006
Conclusions
•
•
•
•
•
More mixture testing (a)
Experimental design needs true control
Shingle only study (b)
Field reviews of past projects (c)
Re-evaluate current Mn/DOT spec (d)
McGraw, July 2006
Additional National
Developments
• New AASHTO specification
• EPA / CMRA study
• www.ShingleRecycling.org
• Asbestos data base
States Using RAS
(in 1999)
Justus, September 2004
Ayres, April 2004
AASHTO Specification (continued)
• Deleterious material maximum limits (Section 8):
(material retained on the No. 4 sieve)
– Heavy fraction = 0.50%
– Lightweight fraction = 0.05%
Missouri Shingle Spec
• Extrinsic Material Allowance Raised
– 3.0% Total
– 1.5% Wood
AASHTO Specification (continued)
• Asbestos levels:
“…shall be certified to be asbestos free.” (Section
5.2)
“(Tear-off shingles are) construction debris and
various state and local regulations may be applicable
to its use. The user of this specification is advised to
contact state and local transportation departments
and environmental agencies to determine what
additional requirements may be necessary.” (Note
2)
Asbestos Risk
• Incidence of asbestos is extremely low
• Average content was only:
– 0.02% in 1963
– 0.00016% in 1973
NAHB, 1999
ASRAS Data
• Iowa (1,791 samples), no hits
• Maine (118 samples), no hits
• Mass:
– (2,288 composite samples) 11 hits < 1%
– (69 tarpaper samples) 2 < 5%
– (109 ground RAS samples) 2 < 1%
• Florida (287 samples), 2 hits > 1%
Ruesch, April 2003.
ASRAS Data
(continued)
•
•
•
•
Missouri (6 samples), no hits
Hawaii (100 samples), 1 hit > 1%
Minnesota (156 samples), no hits
Minnesota (50 tarpaper), 1 hit @ 2% - 5%
We still want more data!
(for EPA / CMRA project.)
Ruesch, April 2003.
DKA / AES
Airborne Fiber Tests
As part of the RMRC Project:
Environmental Testing of Airborne Particles at
The Shingle Processing Plant
Krivit, April 2003.
La Cross County, WI
Shingles Recycling Demonstration
• Marty Cieslik (Foth & Van Dyke) and
Brian Tippetts (La Crosse County
Solid Waste Director)
• Dr. Ervin Dukatz (VP-Materials and
Research - Mathy Construction
Company - Onalaska).
Use of Shingles on Dairy Farms
West Central, WI
• Bernie Wenzel (Resource Recovery
Team - Stratford, WI) and Deb Pingel
(DNR-West Central Region).
Summary Highlights
• Risk from asbestos is negligible to nonexistent
• Two rounds of sampling for total:
– Dust (1999)
– Fibers (2002)
• Common sense and best management
practices can help prevent employee
exposure
Krivit, April 2003.
List of Roofing Waste Items
Included for Recycling
“YES” (Include these items):
• Asphalt shingles
• Felt attached to shingles
List of Roofing Waste Items
Excluded for Recycling
“NO” (Do NOT include):
•
•
•
•
•
•
Wood
Metal flashings, gutters, etc
Nails (best effort)
Plastic wrap, buckets
Paper waste
No other garbage or trash
Lista de material para techos basura
artículo para reciclar:
Si (Incluya)
• Repias
• Papel del fietro
No / Ningun
(No incluya)
• Madera
• Metal: flashings, canales
• Clavos
• Plastico
• Basura de papel
• La otra basura
Comprehensive
Quality Control Plan
 Quality control of supply
 Worker safety and health protection
 Final product quality, storage and handling
 Shingle recycling system design
 Final product sampling and lab testing
Quality Specs:
Scrap Feedstock and
Final Products
• Free of debris / trash / foreign matter
• Tear-off scrap must be asphalt shingles
only
• No nails!
Recommendations
1. Continue MARKET DEVELOPMENT
(a)
2. MANAGE the asbestos issue (b)
3. PROTECT employee health and safety (c)
4. GUARANTEE your product quality (d)
NCAUPG
• Conference in Minneapolis, MN
January 10-11, 2007
Contact:
Lynn Warble at
(765) 463-2317 or [email protected]
• http://cobweb.ecn.purdue.edu/~spave/NCAUPG/Index.html
NCAUPG
January 2007 Conference
•
Hot Mix Asphalt Technical Conference Session II Wednesday,
January 10, 2007, 1:00 – 5:00 p.m. Moderators: Mike Kvach and Will
Stalcup, NCAUPG Co-Chairmen
– HMA Economics 101
• 1:00 – 2:00 RAP and Recycling of Asphalt Shingles:
–
Roger Brown, Pace Construction
– Joe Schroer, Missouri DOT
– Dusty Ordorff, Bituminous Roadways
– Dan Gallagher, Gallagher Asphalt
NCAUPG
January 2007 Conference
•
Hot Mix Asphalt Technical Conference Session III Thursday, January
11, 2007, 7:30 – 11:45 a.m.
•
Moderators: Mike Kvach and Will Stalcup, NCAUPG Co-Chairmen
– 9:30 – 10:00 Low Temperature Cracking:
Mihai Marasteanu, University of Minnesota
C&D Recycling World
Exposition and Show
• Conference in San Antonio, Texas
January 14 - 16, 2007
Contact:
Lola Perez or Maria Miller at
800.456.0707
or [email protected] or
[email protected]
• http://www.cdworldshow.com/
Dan Krivit and Associates
651-489-4990
[email protected]