Field Performance of Warm Mix Asphalt Technologies (2014) / Chapter Skim
Currently Skimming:
Pages 201-243
The Chapter Skim interface presents what we've algorithmically identified as the most significant single chunk of text within every page in the chapter.
Select key terms on the right to highlight them within pages of the chapter.
From page 201... ...
Effects of WMA on Plant Energy and Emissions and Worker Exposures to Respirable Fumes P A R T 2
|
From page 202... ...
205 Interest in the use of warm mix asphalt (WMA) has grown faster than any other new asphalt technology of the past several decades.
|
From page 203... ...
206 Date Project Location Plant Site and Description Mixes July 19–21, 2010 County Road 513, Rapid River, Michigan Escanaba, Michigan, uninsulated parallel-flow drum HMA, Advera, Evotherm 3G Sept. 14–15, 2010 Calumet Avenue, Munster, Indiana Griffith, Indiana, insulated counter-flow dryer HMA, Gencor Foam, Evotherm 3G, Heritage Wax Oct.
|
From page 204... ...
207 Background on Energy Used to Produce HMA and WMA Asphalt mixtures are produced by drying aggregate particles and mixing the dry aggregate with an asphalt binder at a temperature sufficient to (1) coat the aggregates and (2)
|
From page 205... ...
208 Figure 2.1. Energy use as a function of aggregate heating.
|
From page 206... ...
209 for some of the difference between theoretical and observed fuel savings (Harder et al.
|
From page 207... ...
210 Fuel firing rate can be calculated from the average exhaust flow rate and oxygen concentration using the following equation: ( ) = × × − 60 20.9 % 20.9 2 Fuel Usage Q O F where: Fuel Usage = MMBtu/hr; 60 = min/hr, converts flow per minute to flow per hour; Q = average stack gas dry volumetric flow rate (dscfm)
|
From page 208... ...
Site Plant1 Mix Avg. Stockpile Moist.
|
From page 209... ...
Site Plant Mix Avg.
|
From page 210... ...
213 on mix temperature were calculated using a specific heat of 0.24Btu/lb/°F for the asphalt mixture. The difference in each pair of average HMA and WMA mix temperatures at each site was multiplied by 0.24Btu/lb/°F, converted to MMBtu, and expressed as a percentage of the difference (delta)
|
From page 211... ...
0.15 0.20 0.25 0.30 0.15 0.20 0.25 0.30 N CH RP 9 -4 7A M ea su re d M M Bt u Astec Predicted MMBtu Parallel-flow Double Barrel Counter-flow Line of Equality Figure 2.3. Astec fuel calculation 3.0 (predicted)
|
From page 212... ...
215 fuel usage for the Montana HMA was 0.157 MMBtu/ton, compared to an average of 0.272 MMBtu/ton for all other HMA and 0.256 for the Michigan and Indiana HMA, which were produced at the same average temperature. This indicates a savings of 0.052 MMBtu/ton per percent of moisture reduction.
|
From page 213... ...
216 Reported Emissions Reductions from WMA Given that most pollutants of concern from asphalt plants result from combustion, they can be reduced simply by reducing fuel consumption through production of warm mix asphalt (WMA)
|
From page 214... ...
217 of equal areas, each of which will be sampled using a traverse point. The number of traverse points depends on the diameter of the stack and the distance of the sampling points from any obstructions that may cause turbulence in the stack gas flow.
|
From page 215... ...
218 Figure 2.5. CO2 emission rates.
|
From page 216... ...
219 Figure 2.7. CO emissions.
|
From page 217... ...
220 the CO and VOC emissions, respectively. Overall, CO emissions were elevated at the Indiana site compared to the other sites.
|
From page 218... ...
221 the baghouse fines, and then becomes encapsulated in the WMA. For reference, the EPA's candidate emission factor for a drum plant using recycled fuel oil is 0.058 lb/ton and for natural gas it is 0.0034 lb/ton (RTI International 2004)
|
From page 219... ...
222 Figure 2.11. Frequency distribution of formaldehyde emissions.
|
From page 220... ...
223 Summary Stack emissions were measured on three multi-technology projects consisting of a total of eight WMA mixes and three corresponding HMA control mixes. • As expected, reduced fuel consumption resulted in reduced CO2 emissions for all of the WMA mixes.
|
From page 221... ...
224 Background The primary use of asphalt has been in paving mixes for roadway infrastructures. The United States and Europe combined employ about 400,000 workers in the asphalt paving industry (AI, EU 2011)
|
From page 222... ...
225 with Flexible Pavements of Ohio, showed that WMA reduced emissions by 35%–65% (EES Group 2006, Powers 2009)
|
From page 223... ...
226 Total Organic Matter TOM (Kriech et al.
|
From page 224... ...
227 tures were ≥44°C lower for the WMA as compared to the corresponding HMA. In fact, the HMA at Indiana was within the normal temperature range for WMA (100–140°C)
|
From page 225... ...
228 Average High Low Average High Low Average High Low 9/14/2010 IN HMA 74.7 78.3 66.7 3.2 0.0 10.6 47.7 71.6 34.7 9/15/2010 IN WMA 73.8 83.5 61.4 2.6 1.0 4.5 49.1 67.6 35.4 9/16/2010 IN WMA 68.4 70.5 66.0 6.5 3.0 13.9 78.3 86.7 69.0 9/16/2010 IN WMA 70.3 74.4 66.9 5.0 3.0 6.9 60.6 69.0 52.9 10/19/2010 NY WMA 54.5 56.0 53.2 3.1 5.0 1.2 58.7 74.2 35.0 10/20/2010 NY HMA 56.6 61.0 51.2 1.0 1.8 0.0 48.8 60.0 35.0 10/21/2010 NY WMA 56.3 61.0 52.0 9.3 12.0 7.1 69.5 81.0 52.0 10/22/2010 NY WMA 45.8 48.0 45.0 12.5 16.0 10.0 45.8 53.0 42.0 Temp oF Wind Speed (mph) Humidity %Date Locaon Type Table 2.8.
|
From page 226... ...
229 Product Date Tonnage Lab ID Description Minutes 1 L Air2 TOM (mg/m3) Experiment Average TOM (mg/m3)
|
From page 227... ...
230 0.23–0.41 mg/m3 and 0.16–0.25 mg/m3, respectively)
|
From page 228... ...
231 Figure 2.15. TGA on the PG 64-22 asphalt binders used in New York and Indiana for this study.
|
From page 229... ...
232 All TOM results were above the LOD, demonstrating that it is a useful measure for assessing reductions in worker breathing zone exposures with the use of WMA. Results for these two sites appeared to bracket the high and low ends of the spectrum of asphalt paving worker breathing zone exposures.
|
From page 230... ...
233 Findings An objective of NCHRP Project 9-47A was to provide relative emissions measurements of warm mix asphalt (WMA) technologies as compared to conventional hot mix asphalt (HMA)
|
From page 231... ...
234 WMA. Significant reductions in sulfur dioxide (SO2)
|
From page 232... ...
235 Asphalt Institute and Eurobitume. The Bitumen Industry -- A Global Perspective, Production, Chemistry, Use, Specification, and Occupational Exposure.
|
From page 233... ...
236 Lauby-Secretan, B., R
|
From page 234... ...
237 A P P E N D I X Documenting Emissions and Energy Reductions of WMA and Conventional HMA During Plant and Paving Operations
|
From page 235... ...
238 PROPOSED REVISION Project Summary Attached is a project summary data entry sheet for use in identifying warm mix asphalt (WMA) technologies and binder characteristics, aggregate, and plant type.
|
From page 236... ...
239 Stack Emissions Testing and Analytical Methods: Suggested test methods are in accordance with U.S. EPA protocol used historically in the HMA industry and are as follows: Sampling point locations per U.S.
|
From page 237... ...
240 Suggested Reporting of Stack Emissions and Energy Results: Average mix production rate in tons/hour - Conventional mix test period - WMA test period Pounds of each pollutant per ton of mix produced - Carbon dioxide, nitrogen oxides, total hydrocarbons, carbon monoxide, sulfur oxides, fine particulates (PM-10) , and formaldehyde - Conventional test period (average all runs)
|
From page 238... ...
241 is normally used as a release agent, a substitute such as B-100 (biodiesel) (CAS Number: 67784-80-9)
|
From page 239... ...
242 While sampling in the field, mix temperatures (both in the hopper and on the mat as it exits the screed strike area) should bemonitored and recorded approximately every 30 minutes, during the test period, with a dial stem thermometer; provided it can be taken safely.
|
From page 240... ...
243 Weather data including ambient temperature and humidity Worker activities Diagrams and/or photographs documenting activities and sampling locations Notation whether paver is equipped with functioning engineering (emission reduction) controls Background-corrected asphalt fume emissions (TP, BSF, and TOM)
|
From page 241... ...
244 Data Collection Forms General Plant Information Project Identification: _______________________ Date: __________ Contractor: ______________________________________ Plant Location: __________________ GPS Coordinates: ______________ Plant Type: _______________________________________ (batch, counter-flow drum, parallel flow drum, or etc.) Plant Manufacturer: _______________________________________________ Burner Model/Type: _______________________________________________ Fuel Type: __________________________ Fuel Temperature (if oil)
|
From page 242... ...
PROCESS DATA SHEET HMA or WMA Technology: ___________________________ Date: ___________________ Page: ____ Time Production Rate Burner % Mix Temp.
|
From page 243... ...
Abbreviations and acronyms used without definitions in TRB publications: A4A Airlines for America AAAE American Association of Airport Executives AASHO American Association of State Highway Officials AASHTO American Association of State Highway and Transportation Officials ACI–NA Airports Council International–North America ACRP Airport Cooperative Research Program ADA Americans with Disabilities Act APTA American Public Transportation Association ASCE American Society of Civil Engineers ASME American Society of Mechanical Engineers ASTM American Society for Testing and Materials ATA American Trucking Associations CTAA Community Transportation Association of America CTBSSP Commercial Truck and Bus Safety Synthesis Program DHS Department of Homeland Security DOE Department of Energy EPA Environmental Protection Agency FAA Federal Aviation Administration FHWA Federal Highway Administration FMCSA Federal Motor Carrier Safety Administration FRA Federal Railroad Administration FTA Federal Transit Administration HMCRP Hazardous Materials Cooperative Research Program IEEE Institute of Electrical and Electronics Engineers ISTEA Intermodal Surface Transportation Efficiency Act of 1991 ITE Institute of Transportation Engineers MAP-21 Moving Ahead for Progress in the 21st Century Act (2012) NASA National Aeronautics and Space Administration NASAO National Association of State Aviation Officials NCFRP National Cooperative Freight Research Program NCHRP National Cooperative Highway Research Program NHTSA National Highway Traffic Safety Administration NTSB National Transportation Safety Board PHMSA Pipeline and Hazardous Materials Safety Administration RITA Research and Innovative Technology Administration SAE Society of Automotive Engineers SAFETEA-LU Safe, Accountable, Flexible, Efficient Transportation Equity Act: A Legacy for Users (2005)
|
Key Terms
This material may be derived from roughly machine-read images, and so is provided only to facilitate research.
More
information on Chapter Skim is available.