A method for realizing high-mixing amount resource utilization of waste asphalt mixture

Abstract

The present application relates to the field of waste asphalt recycling, and relates to a method for realizing high-mixing-amount resource utilization of waste asphalt mixture, which comprises the following steps: cleaning waste asphalt mixture in a broken asphalt pavement layer, and then crushing the waste asphalt mixture to obtain small asphalt particles; cleaning and drying the small asphalt particles to obtain waste asphalt mixture particles; modifying the waste asphalt mixture particles; and mixing the modified waste asphalt mixture, fresh asphalt mixture, a regenerating agent and mineral powder to obtain fresh asphalt mixture. Compared with the prior art, the present application has the advantages of realizing high-mixing-amount resource utilization of waste asphalt mixture.

Description

Technical Field

[0001] This invention relates to the field of waste asphalt recycling, and in particular to a method for achieving high-volume resource utilization of waste asphalt mixtures. Background Technology

[0002] Asphalt is a common road construction material, made from a mixture of asphalt adhesive and aggregate. It has good water tightness, which can effectively prevent rainwater from penetrating into the road base, protect the foundation soil from water erosion, and extend the service life of the pavement. Asphalt also has good flexibility, which can deform under vehicle loads, disperse stress, and reduce the risk of pavement damage. In addition, asphalt pavement is easy to construct, easy to repair, comfortable to drive, has low noise, and can reduce fuel consumption. Therefore, it is widely used in road construction and maintenance.

[0003] However, a large amount of waste asphalt mixture is generated during road maintenance and construction. The recycling of waste asphalt mixture can not only reduce resource consumption and environmental pollution, lower road construction and maintenance costs, and save economic resources, but also conform to the concept of sustainable development, promote green and environmentally friendly road construction, and promote social sustainable development.

[0004] Currently, most waste asphalt mixtures are mixed with fresh asphalt mixtures and heated and stirred at high temperatures to produce recycled mixtures for reuse. However, in existing technologies, fresh asphalt mixtures account for a relatively high proportion, but these resources are limited and expensive, increasing the cost of recycling and reducing the reuse rate of waste asphalt mixtures, leading to environmental pollution and resource waste. Therefore, how to achieve high-volume resource utilization of waste asphalt mixtures is an urgent problem to be solved. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the existing technology and provide a method for high-volume resource utilization of waste asphalt mixtures.

[0006] The objective of this invention can be achieved through the following technical solutions:

[0007] A method for high-content resource utilization of waste asphalt mixtures includes the following steps:

[0008] S1: Take the waste asphalt mixture from the broken asphalt pavement layer, clean it, and then crush it to obtain asphalt particles;

[0009] S2: Wash and dry the small asphalt particles to obtain waste asphalt mixture particles;

[0010] S3: Modify the waste asphalt mixture particles, and then mix the modified waste asphalt mixture, fresh asphalt mixture, recycling agent and mineral powder to obtain fresh asphalt mixture.

[0011] Furthermore, the diameter of the crushed asphalt particles is no greater than 5 mm.

[0012] Furthermore, the cleaning process employs ultrasonic cleaning, and the cleaning environment is alkaline.

[0013] Furthermore, the cleaning time is 5-20 minutes.

[0014] Furthermore, the drying temperature is 40-50°C.

[0015] Furthermore, the modification includes mixing waste asphalt mixture particles with acrylate copolymers at 80°C-100°C.

[0016] Furthermore, the mass ratio of the waste asphalt mixture particles to the acrylate copolymer is 3-15:1.

[0017] Furthermore, the weight ratio of the modified waste asphalt mixture, fresh asphalt mixture, recycling agent and mineral powder is (40-80):(15-25):(5-10):(5-10).

[0018] Furthermore, the modified waste asphalt mixture, fresh asphalt mixture, recycling agent and mineral powder are mixed using mechanical stirring at a frequency of 60-100 rpm.

[0019] Furthermore, the stirring time is 10-20 minutes, and the stirring temperature is 120℃-160℃.

[0020] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0021] By improving the purity and quality of waste asphalt mixtures, the various road performance characteristics of waste asphalt mixtures can be made close to those of fresh asphalt mixtures. Therefore, waste asphalt mixtures can be applied in high-volume applications to fresh asphalt mixtures to improve their utilization rate and realize the resource utilization of waste asphalt mixtures with high-volume content. Attached Figure Description

[0022] Figure 1 This is a schematic flowchart of a method for high-volume resource utilization of waste asphalt mixtures according to the present invention. Detailed Implementation

[0023] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0024] The objective of this invention can be achieved through the following technical solutions:

[0025] A method for high-content resource utilization of waste asphalt mixtures includes the following steps:

[0026] S1: First, the larger impurities (such as stones, wood, etc.) in the waste asphalt mixture are preliminarily cleaned to ensure that the mixture contains only effective components such as asphalt and stone. Then, appropriate crushing equipment (such as jaw crusher, impact crusher, etc.) is used to crush the waste asphalt mixture into smaller particles, which are then crushed to obtain asphalt particles.

[0027] Preliminary cleaning of impurities in waste asphalt mixtures and crushing them with appropriate crushing equipment can improve the purity and quality of waste asphalt mixtures, providing a good foundation for subsequent reuse and treatment, and promoting the effective use of resources.

[0028] S2: Use suitable screening equipment (such as vibrating screens, rotary screens, etc.) to screen the crushed waste asphalt mixture to separate small particles that meet the specified size. The screened material should be smaller than 5mm. Material larger than 5mm should be re-crushed until it is smaller than 5mm to obtain small asphalt particles. Small-particle waste asphalt mixture has better uniformity and stability. Smaller particles can better combine with fresh asphalt mixture, achieving higher adhesion and stability, which is conducive to forming a uniform and compacted recycled mixture. Furthermore, small-particle waste asphalt mixture has better plasticity and paving properties during construction. Smaller particles can better fill and cover the road surface and are easier to hot-compact, which helps improve construction efficiency and quality.

[0029] Small asphalt particles are placed in an ultrasonic cleaner, and an alkaline cleaning solution is added. The ultrasonic cleaning frequency is adjusted to 40kHz, and the cleaning time does not exceed 20 minutes. This removes dirt and grime from the particle surface. The ultrasonic cleaner vibrates at a high frequency, causing microbubbles to form intense eddies and flows in the liquid, providing a more thorough and uniform cleaning effect. This is particularly effective when the surface of waste asphalt mixture particles has fine pores or complex structures, thereby improving the purity and quality of the waste asphalt mixture, reducing interference from impurities, and reducing the need for large amounts of chemical cleaning agents, thus reducing the demand for water and alkaline cleaning solutions, lowering wastewater generation and environmental impact. Furthermore, ultrasonic cleaners have low energy consumption and high energy efficiency.

[0030] The washed asphalt particles are first filtered to remove moisture. Then, the waste asphalt mixture particles are fed into a cyclone dryer via a conveying device. The cyclone dryer is started, causing the particles to rotate and come into contact with hot air. Through the flow of hot air, the moisture on the surface of the particles gradually evaporates. The rotation speed of the cyclone dryer is between 2000 rpm and 3000 rpm, and the hot air temperature is between 40°C and 50°C. The rotational motion in the cyclone dryer ensures that the particles are heated evenly during the drying process. The hot air forms a vortex in the cyclone dryer, causing the particles to be evenly distributed within it, thus achieving uniform drying of the entire particle. Controlling the hot air temperature between 40°C and 50°C ensures that the waste asphalt mixture particles suffer less thermal damage during the drying process. This helps to maintain the chemical composition and properties of the particles. Furthermore, using relatively low hot air temperatures during the drying process reduces energy consumption and environmental impact. The dried waste asphalt mixture particles are obtained.

[0031] S3: Modification of waste asphalt mixture particles. Acrylic copolymers are mixed with washed waste asphalt mixtures at a mass ratio of 3-8:1 at a temperature between 80℃ and 100℃. This modification improves the mixture's viscosity, anti-aging properties, adhesion, and water permeability, contributing to enhanced pavement durability, stability, and damage resistance, thus extending pavement service life.

[0032] The modified waste asphalt mixture, fresh asphalt mixture, recycling agent, and mineral powder are then mixed to obtain fresh asphalt mixture. The weight ratio of the modified waste asphalt mixture, fresh asphalt mixture, recycling agent, and mineral powder is (40-80):(15-25):(5-10):(5-10). The waste asphalt mixture and fresh asphalt mixture are softened by heating and stirring, and then fully mixed with the recycling agent and mineral powder to form recycled asphalt mixture. The stirring frequency is 60-100 rpm, the stirring time is 10-20 minutes, and the stirring temperature is 120℃-160℃.

[0033] The following embodiments are implemented based on the above-described technical solution of the present invention, and provide detailed implementation methods and specific operation processes. However, the scope of protection of the present invention is not limited to the following embodiments.

[0034] The following are more detailed implementation examples, which further illustrate the technical solution of the present invention and the technical effects that can be obtained.

[0035] In the following embodiments:

[0036] Waste asphalt mixtures come from waste materials generated during road maintenance and reconstruction when old asphalt pavements are broken, milled, or stripped off.

[0037] Crushing equipment selection: XB series roller crushing and screening equipment produced by Jiangsu Xibao Heavy Industry Machinery Co., Ltd. This equipment is equipped with a screen and uses a high-frequency vibration motor to drive the screen to vibrate (the screen body is stationary);

[0038] Cyclone dryer selection: JQ type cyclone airflow dryer manufactured by Changzhou Qibao Drying Equipment Co., Ltd.;

[0039] Ultrasonic cleaner selection: ZC-05 model ultrasonic cleaner manufactured by Zhangjiagang Yiyin Ultrasonic Technology Co., Ltd.

[0040] Alkaline cleaning solution stock solution selection: PL-100 model cleaning solution produced by Dongguan Qiquan Cleaning Agent Technology Co., Ltd.;

[0041] The acrylate copolymer was purchased from Hubei Rishengchang New Material Technology Co., Ltd.

[0042] The regenerator was purchased from Shandong Fanya New Materials Co., Ltd.

[0043] The mineral powder was purchased from Leiyun Mineral Products Processing Plant in Lingshou County.

[0044] Example

[0045] This embodiment provides a method for high-volume resource utilization of waste asphalt mixtures, including the following steps:

[0046] S1: The waste asphalt mixture from the broken asphalt pavement layer is cleaned, then crushed to obtain small asphalt particles. A 5mm sieve is used to screen the crushed waste asphalt mixture to separate small particles that meet the specified size. The diameter of the crushed asphalt particles is no greater than 5mm.

[0047] S2: Place the asphalt particles into an ultrasonic cleaner and add alkaline cleaning solution (the weight ratio of asphalt particles to alkaline cleaning solution is 1:15, and the alkaline cleaning solution is a mixture of cleaning solution concentrate and water, with a volume ratio of concentrate to water of 1:50). Adjust the ultrasonic cleaning frequency to 40kHz and the cleaning time to 20 minutes. Then place them into a cyclone dryer at a drying temperature of 50℃, a cyclone dryer speed of 2500rpm, and a wind speed of 20m / s to obtain waste asphalt mixture particles.

[0048] S3: The acrylate copolymer and the cleaned waste asphalt mixture are mixed and modified at a mass ratio of 1:13.2 at a temperature of 90℃ to modify the particles of the waste asphalt mixture. Then, the modified waste asphalt mixture, fresh asphalt mixture (mixed using conventional process), recycling agent and mineral powder are mixed at a mass ratio of 72:16:5:7 to obtain the modified fresh asphalt mixture. During mixing, mechanical stirring is used at a stirring frequency of 60-100 rpm for 15 minutes at a stirring temperature of 140℃.

[0049] The following table compares the performance of asphalt mixtures processed using the method of this invention with those processed using conventional methods in the market:

[0050]

[0051] As shown in the table, the fresh asphalt mixture obtained in this embodiment has superior properties in appearance, such as no bubbles and no lumps, compared with traditional asphalt mixtures. It also has a higher viscosity and can be used as a recycled asphalt mixture.

[0052] The above description of the embodiments is provided to enable those skilled in the art to understand and use the invention. It will be apparent to those skilled in the art that various modifications can be made to these embodiments, and the general principles described herein can be applied to other embodiments without inventive effort. Therefore, the present invention is not limited to the above embodiments, and any improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the invention should be within the protection scope of the present invention.

Claims

1. A method for realizing high-mixing amount resource utilization of waste asphalt mixture, characterized in that, The method comprises the following steps: S1: collecting waste asphalt mixture in broken asphalt pavement layer for cleaning, and then crushing to obtain small asphalt particles; the diameter of the small asphalt particles after crushing is not greater than 5 mm; S2: cleaning and drying the small asphalt particles to obtain waste asphalt mixture particles; S3: mixing the waste asphalt mixture particles and acrylate copolymer at a mass ratio of 13.2:1 at 90 DEG C, and then mixing the modified waste asphalt mixture, fresh asphalt mixture, regenerating agent and mineral powder at a mass ratio of 72:16:5:7 to obtain the fresh asphalt mixture; The acrylate copolymer is a methyl methacrylate-butyl acrylate-methyl methacrylate copolymer; Mechanical stirring is adopted when the modified waste asphalt mixture, fresh asphalt mixture, regenerating agent and mineral powder are mixed, and the stirring frequency is 60-100 r / min; The stirring time is 15 min, and the stirring temperature is 140 DEG C.

2. The method for realizing high-mixing amount resource utilization of waste asphalt mixture according to claim 1, characterized in that, In step S2, ultrasonic cleaning is adopted during the cleaning, and the cleaning environment is alkaline.

3. The method for achieving high-mixing resource utilization of waste asphalt mixture according to claim 2, characterized in that, The cleaning time is 5-20 min.

4. The method for achieving high-mixing resource utilization of waste asphalt mixture according to claim 1, characterized in that, In step S2, the drying temperature is 40-50 DEG C.

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