1、Standard Method of Test for Quantitative Extraction and Recovery of Asphalt Binder from Asphalt Mixtures AASHTO Designation: T 319-15 American Association of State Highway and Transportation Officials 444 North Capitol Street N.W., Suite 249 Washington, D.C. 20001 TS-2c T 319-1 AASHTO Standard Metho
2、d of Test for Quantitative Extraction and Recovery of Asphalt Binder from Asphalt Mixtures AASHTO Designation: T 319-15 1. SCOPE 1.1. This standard describes a procedure for the extraction and recovery of asphalt binder from asphalt mixtures both hot mix asphalt (HMA) and reclaimed asphalt pavement
3、(RAP) that have a minimal effect on the physical and chemical properties of the asphalt binder recovered. This standard is intended for use when the physical or chemical properties, or both, of the recovered asphalt binder are to be determined. It can also be used to determine the quantity of asphal
4、t binder in the HMA or RAP. Recovered aggregate may be used for sieve analysis or other aggregate testing. 1.2. This method is applicable to HMA sampled from the pavement, RAP sampled from the pavement or stockpile, HMA plant production, or laboratory fabricated HMA. 1.3. This procedure may involve
5、hazardous materials, operations, and equipment. This procedure does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this procedure to establish appropriate safety and health practices and determine the applicability of regul
6、atory limitations prior to use. 2. REFERENCED DOCUMENTS 2.1. AASHTO Standards: M 231, Weighing Devices Used in the Testing of Materials T 2, Sampling of Aggregates T 110, Moisture or Volatile Distillates in Hot Mix Asphalt (HMA) T 168, Sampling Bituminous Paving Mixtures T 329, Moisture Content of A
7、sphalt Mixtures by Oven Method 2.2. ASTM Standards: D96, Standard Test Methods for Water and Sediment in Crude Oil by Centrifuge Method (Field Procedure) (Withdrawn 2000) D5361/D5361M, Standard Practice for Sampling Compacted Bituminous Mixtures for Laboratory Testing 3. TERMINOLOGY 3.1. Definition:
8、 3.1.1. asphalt binderan asphalt-based cement that is produced from petroleum residue either with or without the addition of nonparticulate organic modifiers. 2015 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable
9、law.TS-2c T 319-2 AASHTO 4. SUMMARY OF METHOD 4.1. The asphalt mixture is repeatedly washed and filtered with solvent in an extraction/filtration apparatus. Each filtrate is distilled under vacuum in a rotary evaporator with the asphalt remaining in the flask. After recovery of the final filtrate, t
10、he solution is concentrated to about 300 mL and centrifuged to remove the aggregate fines. The decanted solution is distilled under vacuum to remove the extraction solvents. Nitrogen gas is introduced during the final phase of distillation to drive off any remaining traces of solvents. The quantity
11、of asphalt binder in the asphalt mixture is calculated (optional) and the recovered asphalt (distillation residue) sample is subjected to further physical and chemical testing as required. The recovered aggregate can then be used for sieve analysis or other aggregate testing, if desired. 5. SIGNIFIC
12、ANCE AND USE 5.1. This method is used for obtaining recovered asphalt binder residue samples from asphalt mixture samples for further physical and chemical analyses, and for the optional calculation of asphalt binder content. 6. APPARATUS 6.1. Extraction Vessel1The extraction vessel shall be a devic
13、e as shown in Figure 1, and shall have a 130-mm-long piece of 150-mm I.D. Schedule 80 aluminum pipe or Schedule 80, Grade 304 stainless steel pipe (Figure 2) with removable top and bottom 13-mm-thick aluminum or stainless steel plates. The top plate (Figure 3) shall have a mixing motor mount and 19-
14、mm port for adding solvent. The bottom plate (Figure 4) shall be equipped with a quick-connect fitting. Four 100-by-25-mm baffles (Figure 5) shall be mounted in the extraction vessel, followed by a 3-mm aluminum ring, 2-mm (No. 10) mesh screen, spacer (Figure 6), 0.3-mm (No. 50) mesh screen, another
15、 spacer, 0.075-mm (No. 200) mesh screen, then another 2-mm (No. 10) mesh screen, as shown in Figure 1. Note 1A vessel available from Pass Industries (133 MacArthur Court, Nicholasville, KY 40356, telephone number 859-881-0205) has proven acceptable for these requirements. 6.2. In-Line FilterThe in-l
16、ine fine filter apparatus shall be a cartridge type with 20-m retention and at least 820 cm3of effective filter area. The filter apparatus shall be able to be removed from the system to accommodate weighing before and after the procedure. The filter shall be capable of withstanding heat up to 135C w
17、ithout degradation in order to accommodate oven drying of the filter apparatus. Note 2Whatman Polycap 75 HD (Catalog Number 6703-7521) or equivalent is a suitable filter (Whatman Inc., 9 Bridewell Place, Clifton, NJ 07014). 6.3. Filtrate Flasks with Tubulation1000 mL (two required). 6.4. Round-Botto
18、m Flasks1000 mL, with cork stands. 6.5. Gas FlowmeterCapable of indicating a gas flow up to 1000 mL/min. 6.6. Rotary Evaporator Devicewith transfer and purge tubes, capable of holding a recovery flask in oil at a 15 angle and rotating at 40 r/min. Note 3The Buchi Rotavapor RE-120 has proven acceptab
19、le for these requirements (Buchi, Labortechnik AG, Postfach, 9230 Flach 1, Switzerland). 6.7. Hot Oil BathCapable of heating oil to 180C. 2015 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-2c T 319-3 AAS
20、HTO Figure 1Extraction Vessel 65432178910121361014415311(1) 2-ISO 12 RT (0.75-in. NPT) plug(2) ISO 8 RT (0.5-in. NPT) fitting with16-mm I.D. hole for motor shaft(3) 12 M5 0.5-mm wing nuts(4) 12 M5 0.5 50-mm studs(5) Extraction vessel top(6) 3 vision gaskets, 3 mm thick, 16-mmwidth with holes to fit
21、over studs(7) Extraction vessel housing(8) Aluminum baffle(9) Aluminum ring, 3 mm thick, 148-mmO.D., 10-mm width(10) Stainless steel screens, 10 mesh(11) Metal spacers(12) #50 screen(13) #200 screen(14) Extraction vessel bottom(15) ISO 4 RT (0.75-in. NPT) quick-connect fitting 2015 by the American A
22、ssociation of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-2c T 319-4 AASHTO Figure 2Extraction Vessel Housing 2015 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a viola
23、tion of applicable law.TS-2c T 319-5 AASHTO Notes: 1. Not to scale. 2. Assume a tolerance of 0.2 mm unless otherwise noted. Figure 3Extraction Vessel Top Plate 2015 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable
24、 law.TS-2c T 319-6 AASHTO Notes: 1. Not to scale. 2. Assume a tolerance of 0.2 mm unless otherwise noted. Figure 4Extraction Vessel Bottom Plate 2015 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-2c T 31
25、9-7 AASHTO Figure 5Extraction Vessel Baffle 2015 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-2c T 319-8 AASHTO Figure 6Extraction Vessel Spacer 6.8. Single-Speed Mixing Motor150 W (1/5hp), 30 r/min. 6.
26、9. CentrifugeBatch unit capable of exerting a minimum centrifugal force of 770 times gravity. 6.10. Wide-Mouth Centrifuge Bottles250 mL. 6.11. OvenCapable of maintaining a temperature of 110 5C. 6.12. BalanceOf suitable capacity, meeting the requirements of M 231 for Class G 2 balances. 6.13. Thermo
27、meterHaving a range of 30 to 300C. 6.14. UtilitiesVacuum source and cooling water source. 6.15. Scale (optional)Having a capacity of 12 kg or more, sensitive to 0.1 g or less, and accurate within 0.1 percent of the test load at any point within the range of use for this test. Within any 100-g range
28、of test load, a difference between readings shall be accurate within 0.1 g. 6.16. 6-mm Diameter Polypropylene TubingVarying lengths, for transferring solution throughout the procedure. Note 4To avoid contamination of the sample due to solvent degradation of the tubing, do not substitute Nalgene or r
29、ubber tubing for the polypropylene tubing specified. 6.17. Copper TubingOf an amount and size adequate to connect the apparatus as shown in Figure 7. 7. MATERIALS AND REAGENTS 7.1. Solvent (n-propyl bromide or trichloroethylene, reagent grade; or toluene, reagent grade)If using toluene, combine with
30、 ethanol, absolute, in proportions of 85 percent toluene and 15 percent ethanol after the third wash (Section 12.2). 2015 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-2c T 319-9 AASHTO 7.2. Nitrogen Gas
31、at least 99.95 percent pure, in a pressurized tank with a pressure-reducing regulator valve. 8. HAZARDS 8.1. Use solvents only under a fume hood or with an effective surface exhaust system in a well- ventilated area. Observe the manufacturers recommended safety precautions when using compressed nitr
32、ogen. 9. SAMPLING 9.1. Obtain asphalt mixture samples in accordance with T 168. When sampling from a compacted roadway, remove specimens from the roadway in accordance with ASTM D5361/D5361M. When sampling RAP, refer to T 2 for aggregate sampling. 10. PREPARATION OF APPARATUS 10.1. Preparing the Ext
33、raction VesselInstall the baffle piece and other internal parts in the order shown in Figure 1. Tightly and evenly fasten the bottom end piece (with the quick-connect fitting) of the vessel with wing nuts or hexagonal nuts. 10.2. Preparing the Rotary EvaporatorTurn on the cooling water. Turn on the
34、oil bath, and set the temperature to 100 2.5C. Place six 3-mm glass boiling beads in a 1000-mL round-bottom flask. Attach this recovery flask to the rotary evaporator, and immerse approximately 38 mm of the flask into the oil bath. Set the angle of the recovery flask, from the horizontal to the bath
35、, at 15 degrees. Set the flask rotation at 40 r/min. Clamp the empty condensate flask onto the condenser. Attach the transfer tube inside the neck of the rotary evaporator. Attach the filtrate transfer line to the external fitting on the neck of the rotary evaporator. 11. STANDARDIZATION 11.1. At le
36、ast every six months, verify the calibration of the oil bath temperature detector by using a certified mercury-in-glass thermometer of suitable range that is accurate to 0.2C. Immerse the thermometer in the oil bath close to the thermal detector, and compare the temperature indicated by the certifie
37、d thermometer to the temperature setting for the oil bath. If the temperature indicated by the thermal detector does not agree with the certified thermometer within 0.5C, perform additional calibration or maintenance. 11.2. At least every six months, use a mercury manometer or other certified pressu
38、re measurement device to verify calibration of the vacuum indicator. If the vacuum indicator and the certified pressure measurement device do not agree within 0.1 kPa, perform additional calibration or maintenance. 11.3. At least every six months, verify the rotational velocity of the rotary evapora
39、tor. 11.4. At least every six months, verify the flow rate of the nitrogen flowmeter. 2015 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-2c T 319-10 AASHTO 12. PROCEDURE 12.1. Sample Preparation: 12.1.1.
40、 If a sample of asphalt mixture is not sufficiently soft to separate with a spatula or trowel, place the sample in a large, flat pan, and warm it in an oven at 110 5C only until it can be handled or mixed. 12.1.2. Split or quarter the loose asphalt mixture sample until an amount of the sample that w
41、ill yield approximately 50 to 60 g of extracted asphalt binder is obtained. Typically 1000 g of asphalt mixture is sufficient. Note 5This procedure works best when recovering less than 60 g of asphalt binder. Therefore, if the asphalt binder content of the mix is already known, then the mass of the
42、original sample required is that which yields about 50 to 60 g of asphalt binder. Note 6The maximum aggregate size in the test specimen will affect the calculated asphalt content. If the calculated results from this standard are used to represent the asphalt content of the asphalt mixture from which
43、 the sample was obtained, use a minimum mass of test specimens for calculations that will ensure that inclusion or removal of one maximum size particle will not change the calculated asphalt content by more than 0.05 percent. This restriction may require testing multiple test specimens. 12.1.3. If t
44、he asphalt binder content is to be determined, obtain a separate test specimen from the asphalt mixture sample. Determine the moisture content in accordance with T 110 or T 329 and record the mass percent of water in the test specimen. 12.2. Extraction and Filtration: 12.2.1. Place the asphalt mixtu
45、re sample in the extraction vessel. Put the gasket and the upstream end piece on the vessel, and fasten the wing nuts tightly and evenly, creating a secure seal. 12.2.2. Charge 600 mL of solvent through the 19-mm port on the upstream end of the extractor. Blanket the interior of the extraction vesse
46、l by injecting nitrogen through the upstream port at a rate of 1000 mL/min for 1 min. Close the port with the threaded plug. Attach the extractor to the motor. Start the motor, and mix for 5 1 min at 30 r/min. Turn off the motor. 12.2.3. Remove the extractor; place it on a stand, and attach the quic
47、k-connect fitting to the first filtrate-receiving flask. Ensure the filtrate transfer line is closed. Remove the upstream port, and blanket the extractor with nitrogen at a rate of 400 mL/min while drawing the asphalt/solvent solution into the first flask. Apply a vacuum of 93.3 0.7 kPa (700 5 mm Hg
48、) to the first filtrate-receiving flask in order to draw the material from the vessel. Continue drawing the solution into the first flask until there is no noticeable amount of solution exiting the vessel. Turn off the vacuum. 12.2.4. Filtering through the in-line cartridge filter, switch the vacuum
49、 to the second filtrate-receiving flask, and apply a vacuum of 93.3 0.7 kPa. Filter until there is no noticeable amount of solution remaining in the first flask or the filter. Turn off the vacuum. 12.2.5. After filtration, open the filtrate transfer valve on the second receiving flask and allow the solution to flow from the filtrate-receiving flask to the recovery flask. Continue the transfer until the filtrate-receiving flask is empty or the recovery flask is about two-thirds full; then, beg
