Market background

By 2019, China’s total road length had reached 4.846,500 km and expressways reached 142,600 km, ranking first in the world. At the same time of the rapid construction of domestic expressways, it has also entered a continuous large-scale maintenance period. Asphalt pavement in the maintenance and expansion of the construction of a large number of waste materials, these old materials regeneration, not only reduce environmental pollution, but also reduce material consumption, is an important means to achieve the sustainable development of highway transportation and urgent need. Through the asphalt pavement recovery material recycling technology, the old asphalt pavement asphalt mixture is dug and recovered, broken and screened, and then an appropriate amount of new aggregate and new asphalt are added, and the recycled asphalt mixture is formed to meet the performance requirements, and then used for pavement or base construction. According to the current process and technical conditions, there are two main technical ways for the regeneration of old asphalt pavement materials: first, the thermal regeneration technology is mainly aimed at restoring the performance of old asphalt; Second, it is a cold regeneration technology that consumes a lot of old materials as the main mouth.

In 2019, in order to improve the recycling level of km pavement materials and ensure the quality of asphalt pavement regeneration projects, the Ministry of Transport revised JTG F41-2008 “Technical Specification for Highway Asphalt Pavement Regeneration” and promulgated “JTG/T 5521-2019 Technical Specification for Highway Asphalt Pavement Regeneration”.

automatic asphalt extractori is mainly used in the field of thermal regeneration.

Asphalt mixture analyzer for pavement asphalt recycling technology solutions

Among them, there are clear quality requirements for asphalt mixture recovery material (RAP) in the regulations:

Bitumen was extracted by means of extractor and then the content of bitumen and related bitumen indexes were analyzed.

Asphalt content and asphalt performance testing of asphalt mixture recovery (RAP) shall be performed in accordance with the following requirements:

Asphalt mixture analyzer for pavement asphalt recycling technology solutions

1, RAP heating and drying to constant weight, heating temperature of 60℃.

2, the current “Highway engineering asphalt and asphalt mixture test Regulations” (JTGE20)T0726 Absen method to recover asphalt from asphalt mixture recovery material (RAP). If other methods are used, repeatability and reproducibility tests and blank bitumen calibration are required.

3, measure the content of asphalt and recovered asphalt of 25℃ penetration, 60℃ viscosity, softening point, 15℃ ductility and other indicators.

4. Blank asphalt calibration must be carried out in any of the following cases: When replacing the Absen asphalt recovery equipment; When changing trichloroethylene varieties or suppliers; When the performance of recovered asphalt is abnormal; When the source of asphalt mixture recovery material (RAP) changes.

Asphalt mixture analyzer for pavement asphalt recycling technology solutions

5, the allowable error of the renaturation test is: needle size ≤5(0.1mm), viscosity ≤ 10% of the average, softening point ≤2.5℃; The allowable error of reproducibility test is: needle penetration ≤10(0.1mm), viscosity ≤ 15% of the average, softening point ≤5.0℃. If the allowable error range is exceeded, the recovered asphalt should be discarded, re-calibrated and recovered.

At the same time, the proportion of asphalt mixture recovery material (RAP), the amount of new asphalt label and regenerant should also refer to the recovered asphalt grade. Asphalt mixture recovery material (RAP) in asphalt mixture blending rate is low, laboratory research is mostly 30% to 40%, the solid engineering application is lower, generally 20% to 30%.