Presentation on theme: "Shingles Recycling A presentation by Dan Krivit at the 49 th Annual Wisconsin Asphalt Paving Conference In Waukesha, Wisconsin Wednesday, November 15,"— Presentation transcript:
Shingles Recycling A presentation by Dan Krivit at the 49 th Annual Wisconsin Asphalt Paving Conference In Waukesha, Wisconsin Wednesday, November 15, 2006
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
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
Creep Stiffness (MO vs. MN) (@ 100 seconds) Marasteanu, July 2006
Creep Stiffness (MO vs. MN) (@ 500 seconds) 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 Marasteanu, July 2006 Bending Beam Rheometer (BBR) (a) Direct Tension Tests (DTT) (b)
BBR Conclusions (continued) Marasteanu, July 2006 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)
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
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 non- existent 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)No / Ningun (No incluya) Repias Madera Papel del fietro 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 firstname.lastname@example.org@purdue.edu 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@example.com or firstname.lastname@example.org@giemedia.com email@example.com http://www.cdworldshow.com/
Dan Krivit and Associates 651-489-4990 DKrivit@bitstream.net