CN102728095A - Recovering method of asphalt in asphalt mixture - Google Patents

Abstract

The invention discloses a recovering method of asphalt in an asphalt mixture. The method comprises the steps that: asphalt in asphalt mixture is extracted by using a centrifugal separation method specified by highway engineering asphalt and asphalt mixture testing procedures, such that an asphalt solution is obtained; the obtained asphalt solution is placed in a beaker and is allowed to stand for 24h for precipitation, and an upper-layer asphalt solution is obtained; the obtained asphalt solution is subjected to asphalt recovery by using an Abson method specified by the highway engineering asphalt and asphalt mixture testing procedures; the obtained recovered asphalt is placed in an aluminum spoon with a relatively large diameter, and is evaporated for 4h under a temperature of 130 DEG C in a baking oven, such that final recovered asphalt is obtained. The obtained final recovered asphalt can be used in various performance tests. With the recovering method of asphalt in asphalt mixture, the influences such as mineral powder and trichloroethylene residual solutions during the extraction and recovery processes upon the performances of asphalt can be effectively eliminated, such that the performance test accuracy of the recovered asphalt can be ensured.

Description

A kind of asphalt medium pitch recovery method

Technical field

The present invention is a kind of test method that is used for effectively reclaiming the asphalt medium pitch, not only helps the bitumen aggregate ratio of accurate Evaluation of asphalt mixture, helps to reclaim the accurate test of back asphalt performance simultaneously, belongs to asphalt highway detection technique field.

Background technology

Existing research shows; Domestic most popular mixture gradation analysis at present and bitumen recovery process; Centrifugal extraction process and A Busen absorption method, the asphalt performance variability that extracting is reclaimed is bigger, and the coefficient of variation of its viscosity can reach 20%～45%; Analyze the reason of its generation, can be summed up as following two aspects:

In the centrifugal extractive process; The improper pitch that causes of test operation fails from gather materials, to extract fully; This incomplete extracting not only can cause bitumen content to be underestimated (between about 0.1%-0.5%); And the marked change that possibly cause reclaiming asphaltic nature of the pitch that is absorbed by gathering materials part, variation tendency then depends on high viscosity or low viscosity pitch composition and remains in and gather materials.And in the extracting removal process, have a small amount of tiny mineral powder granular and sneak into and reclaim in the pitch, and then changed the physical property of pitch.

Centrifugal extract is carried out in the A Busen removal process corresponding test operation: programming rate, CO ₂The time and the quantity that feed; The speed that solvent distills out, the conservation condition after distillation finishes etc. is difficult to grasp, and not only can cause trichloro-ethylene to remain in and reclaim in the pitch; Also can cause and reclaim the aging of pitch; And the A Busen flask is 500ml only, the pitch amount that once reclaims seldom, too much repeated test also can cause bigger test error.

Because the bitumen recovery difficulty is big, bad if recovering condition is grasped, the character that reclaims pitch variation occurs and just is difficult to avoid.But domestic research and data to pitch extracting and recovery method itself are less, and the whole bag of tricks basically all is with reference to the mat formation regulation of test method(s) of U.S. ASTM and Japanese road association.Because national conditions are different with experimental condition, these methods applicability and accuracy at home lacks detailed research, and the application of this test for asphalt performance, asphalt pavement regeneration and popularizing etc. brings very big obstacle.

Therefore, the present invention provides a kind of asphalt medium pitch recovery method, thereby the pitch in the asphalt of simple possible reclaims evaluation.

Summary of the invention

Technical problem:The technical problem that the present invention will solve provides a kind of recovery method of asphalt medium pitch, through the pitch in the accurate recovery asphalt, can judge the bitumen aggregate ratio of asphalt accurately, also can test the performance that reclaims pitch accurately.

Technical scheme:For solving the problems of the technologies described above, the technical scheme that the present invention adopts is:

A kind of asphalt medium pitch recovery method is characterized in that comprising the steps:

Step 1: the centrifugal separation according to highway engineering pitch and asphalt testing regulations regulation is carried out extracting to the pitch in the asphalt, obtains cold primer-oil;

Step 2: the cold primer-oil with step 1 is obtained, place beaker, staticly settled 24 hours, obtain the upper strata cold primer-oil;

Step 3: with the cold primer-oil that step 2 is obtained, the A Busenfa that stipulates according to highway engineering pitch and asphalt testing regulations carries out bitumen recovery;

Step 4: the recovery pitch that step 3 is obtained is positioned in the aluminium spoon of larger caliber, and evaporation is 4 hours in 130 ℃ of baking ovens, to obtain final recovery pitch.

The A Busenfa operation of step 3 is adjusted to 130 ℃ with test temperature.

The final recovery pitch that step 4 is obtained can be used for each item performance test.

Beneficial effect:A kind of asphalt medium pitch recovery method provided by the invention can effectively be eliminated breeze and trichloro-ethylene residual solution etc. in the extracting removal process to the influence of asphalt performance, thereby guarantees to reclaim the accuracy of the performance test of pitch.The test method that the present invention proposes, test data accurately and reliably, test method is simple and feasible, is easy to test, has very excellent generalization values.

Test method of the present invention has not only been carried out effective checking through a large amount of laboratory tests, in entity project, has obtained good application simultaneously.Laboratory test and entity project have all been verified reasonability, reliability and the practicality of test method of the present invention.

The specific embodiment

Carry out the compound sampling according to the asphalt sampling method (T0701-2011) of " highway engineering pitch and asphalt testing regulations " (JTG E20-2011) regulation, perhaps carry out the compound sampling according to actual needs; Asphalt after the sampling is carried out extracting according to the centrifugal separation (T0722-1993) of " highway engineering pitch and asphalt testing regulations " (JTG E20-2011) regulation to the pitch in the asphalt; Obtain cold primer-oil, can will carry out extracting repeatedly according to the used in amounts of asphalt performance test and reclaim; With the cold primer-oil that obtains; Place beaker; The capacity of beaker is advisable with the capacity that adapts to the A Busen returnable bottle, staticly settled 24 hours, during can not carry out disturbance to it; This step purpose is breeze residual in the cold primer-oil is removed, and avoids the interference effect of breeze in the follow-up asphalt performance test; The cold primer-oil that obtains is further carried out bitumen recovery according to the A Busenfa (T0726-2011) of " highway engineering pitch and asphalt testing regulations " (JTG E20-2011) regulation; In the removal process test temperature is adjusted into 130 ℃; Test temperature with respect to regulation and stipulation is lower, can alleviate cause in the bitumen recovery process aging; The above-mentioned recovery pitch that obtains further is positioned in the suitable aluminium spoon; Evaporation is 4 hours in 130 ℃ baking oven; Can be further the trichloro-ethylene that remains in the pitch be removed, avoiding of the influence of residual trichloro-ethylene, thereby obtained suitable recovery pitch asphalt performance; The pitch that reclaims at last can be used for each item performance test analysis.

Claims (2)

1. an asphalt medium pitch recovery method is characterized in that comprising the steps:

Step 1: the centrifugal separation according to highway engineering pitch and asphalt testing regulations regulation is carried out extracting to the pitch in the asphalt, obtains cold primer-oil;

Step 2: the cold primer-oil with step 1 is obtained, place beaker, staticly settled 24 hours, obtain the upper strata cold primer-oil;

Step 3: with the cold primer-oil that step 2 is obtained, the A Busenfa that stipulates according to highway engineering pitch and asphalt testing regulations carries out bitumen recovery;

Step 4: the recovery pitch that step 3 is obtained is positioned in the aluminium spoon of larger caliber, and evaporation is 4 hours in 130 ℃ of baking ovens, to obtain final recovery pitch.

2. a kind of asphalt medium pitch recovery method as claimed in claim 1 is characterized in that: the A Busenfa operation of step 3 is adjusted to 130 ℃ with test temperature.