Method for preparing modified asphalt

Abstract

The invention discloses a method for preparing modified asphalt by coal direct liquefaction oil residue, wherein, 150 DEG C to 280 DEG C molten coal direct liquefaction oil residue and 100 DEG C to 180 DEG C molten base asphalt are mixed evenly at 150 DEG C to 280 DEG C to form liquid melt so as to obtain modified asphalt. With simple process, energy saving, environmental protection and high efficiency, the method improves the quality of modified asphalt.

Description

technical field [0001] The invention relates to a method for preparing modified asphalt, in particular to a method for preparing modified asphalt by directly liquefying oil residue from coal. Background technique [0002] Modern highway pavement uses asphalt as a binder, which enhances the cohesive force between mineral materials, improves the strength and stability of the mixture, and improves the quality and durability of the pavement. However, with the increasing flow of high-grade highways, obvious canalized traffic, high vehicle speed, increasingly heavy bearings, and the drastic temperature changes caused by my country's unique monsoon climate, the performance requirements of asphalt are getting higher and higher. Sufficient strength and thermal stability, sufficient elasticity and plasticity at low temperature. However, due to the high wax content of asphalt in our country, high temperature sensitivity, poor cohesive force, low elongation, poor thermal stability and l...

AI Technical Summary

Problems solved by technology

In the preparation process described in this patent application, the reactants are the coal liquefied oil residue cooled to solid and the liquid phase matrix pitch in the molten state. Although the oil residue has been pulverized, the reaction is a heterogeneous liquid-solid reaction. When dispersing the liquefied oil residue (solid state) into the base asphalt (molten liquid state), on the one hand, it takes time to convert the liquefied oil residue from solid to liquid state, and on the other hand, it also takes time to disperse the oil residue transformed into molten liquid state into the base asphalt In this process, the mixing time is too long, because the thermal melting temperature of the oil residue (150-280°C) is higher than that of the base asphalt (100-180°C), so that the base asphalt can be used for a long time in the process of mixing and dispersing the two At a higher temperature, this will damage some physical properties of the base asphalt to a certain extent, and then reduce or damage the physical properties of the modified asphalt prepared by using liquefied oil residue

Moreover, this liquid-solid mixing process also leads to poor mixing and dispersing effect and requires more energy, and when the liquefied oil residue is dispersed into the base asphalt, the hot-melt oil residue will aggregate to make the dispersion effect Difference

In addition, this process also has some other disadvantages, for example, 1. The process consists of transporting oil residue, grinding, screening, heating and mixing, etc., with many steps, time-consuming and laborious; 2. Since the liquefied oil residue is a mixture, grinding The screening method will inevitably cause changes in the composition of the oil residue, thereby reducing the utilization rate of the liquefied oil residue, and the change in the composition of the oil residue will affect the stability of the physical properties of the modified asphalt

3. The process involves the grinding and storage of liquefied oil residue, which consumes space and easily causes environmental pollution