Method for recycling asphalt from asphalt mixture

Abstract

The invention discloses a method for recycling asphalt from an asphalt mixture. According to the method, impurity removal, asphalt solution extraction and asphalt solution distillation are carried out so as to obtain recycled asphalt finally. The method has the advantages that the asphalt mixture is scattered by virtue of drying, the solubility of asphalt is greatly improved due to addition of a bromopropane solvent or a trichloro ethylene solvent, a distillation flask is uniformly heated by use of an oil bath tank capable of automatically controlling temperature, the temperature in the distillation flask can be effectively controlled in the later period of distillation, and the asphalt aging is avoided. The method has good popularization value.

Description

Technical field [0001] The present invention belongs to the field of highway asphalt pavement detection technology, which involves a method of recycling asphalt from the asphalt mixture. Background technique [0002] With the development and vigorous promotion of asphalt regeneration technology, recycling asphalt from the asphalt pavement or asphalt mixture has become a commonly used test method.The degree, as well as analyzing the causes of asphalt pavement, use the regeneration of aging asphalt and the combination of mixture.However, during the recycling of asphalt, various problems are prominent, such as recycling of residual ore powder and solvents in asphalt, aging such as asphalt during testing and testing.Performance is misleading to the design of asphalt regeneration and mixture, and it will inevitably affect the service performance and service life of the recycled asphalt pavement. [0003] "Experimental Regulations on Highway Engineering asphalt and asphalt mixture" alt...

AI Technical Summary

Problems solved by technology

However, in the asphalt recycling process, various problems are highlighted, such as residual mineral powder and solvent in the recycled asphalt, aging of the asphalt during the testing process, etc. If the asphalt recovered from the asphalt mixture cannot reflect the true nature of the asphalt in the asphalt mixture performance, it will mislead asphalt regeneration and mixture design, which will inevitably affect the service performance and service life of recycled asphalt pavement

[0003] Although there is an asphalt recovery method (T0726 Abson method) in JTG E20-2011 "Test Regulations for Asphalt and Asphalt Mixtures in Highway Engineering", this method has the following problems: (1) This method performs high-speed centrifugal separation on the bitumen extract. If a semi-automatic centrifugal separator is used, it needs to be separated many times. The operation process is extremely cumbersome and it is difficult to avoid the residue of mineral powder. This problem; (2) During the distillation process of this method, the distillation temperature (in the flask) is maintained at 160-166 ° C, and it is very easy to cause asphalt aging at this temperature; (3) This method stipulates that after distillation until the solvent stops dripping The asphalt was recovered after finishing the test in 5 minutes, but the solvent residue was less and less likely to be distilled out at the end, and the test was ended only after a delay of 5 minutes, so there was a problem of solvent residue; (4) the distillation bottle used in this method was 500ml, and the actual The asphalt solution is only 350~400ml. According to conventional extraction, it can be calculated that the asphalt content in 400ml asphalt solution is no more than 30g asphalt (according to 1500 asphalt mixture, asphalt ratio is 5%, and the extraction solution is at least 1000ml), and such a small amount of asphalt When taking it out from the distillation flask, part of the asphalt sticks to the wall of the flask, and there is very little asphalt in the end. According to the calculation of nearly 200g of asphalt required for the three basic indicators of asphalt, at least 10 distillations are required to recover, and the operation is cumbersome. Know