Environmentally friendly rubber-modified asphalt, preparation method and application thereof

Abstract

This invention relates to the field of road materials technology, specifically to an environmentally friendly rubber-modified asphalt, its preparation method, and its application. The environmentally friendly rubber-modified asphalt of this invention is prepared from the following components in parts by weight: 100 parts of base asphalt; 1-5 parts of softening oil; the softening oil includes aromatic oil, oleic acid, furfural extract oil, and wax oil; 15-30 parts of micro-nano rubber particles; the micro-nano rubber particles are obtained from desulfurized and activated reclaimed rubber; 0.1-0.3 parts of stabilizer; and 0-3 parts of polymer. Compared with ordinary rubber-modified asphalt, the environmentally friendly rubber-modified asphalt of this invention has higher viscosity, excellent low-temperature and high-temperature performance, stable system, and significantly reduced odor during construction, making it environmentally friendly. This paper describes a wet process for preparing environmentally friendly rubber asphalt using environmentally friendly rubber particles. The preparation process is simple, requiring only one feeding and a colloid mill to obtain high-grade modified asphalt, thus saving production costs.

Description

Technical Field

[0001] This invention relates to the field of road materials technology, specifically to an environmentally friendly rubber-modified asphalt, its preparation method, and its application. Background Technology

[0002] With the rapid development of the transportation industry, the use of rubber tires has been increasing, and the indiscriminate disposal of waste tires has exacerbated environmental pollution and the shortage of rubber resources. How to recycle and reuse waste tires is a crucial issue that urgently needs to be addressed. The rubber powder industry is an important way to comprehensively utilize waste rubber, and the application of rubber powder in road engineering has received widespread attention. However, rubber asphalt still suffers from problems such as unstable quality and poor storage stability during processing and use. Producing rubber asphalt with good uniformity and stability to improve its utilization efficiency is currently a key research direction for rubber asphalt.

[0003] On the one hand, the existing production process of rubber-modified asphalt is environmentally unfriendly and produces a strong odor during construction, hindering its widespread adoption. On the other hand, existing rubber-modified asphalt suffers from poor adhesion due to uneven dispersion of PE material during production. For example, invention patent CN1831043A discloses a method for preparing composite modified asphalt mixtures using a combination of dry and wet processes. This method involves adding 10-23% tire rubber powder to 77%-90% petroleum asphalt to prepare rubber asphalt. Then, 100 parts of mineral aggregate are heated to 160-200℃, and 0.2-0.8 parts of PE are added to the mineral aggregate, followed by 6.5-11 parts by weight of the prepared rubber asphalt. This method avoids segregation of the rubber-modified asphalt, but the direct addition of PE to the aggregate easily leads to uneven dispersion and poor local adhesion. Summary of the Invention

[0004] In view of this, the technical problem to be solved by the present invention is to provide an environmentally friendly rubber-modified asphalt, its preparation method and application. The low-carbon environmentally friendly asphalt provided by the present invention has excellent low-temperature and high-temperature performance, and the system is stable; it has little odor when applied to construction.

[0005] This invention provides an environmentally friendly rubber-modified asphalt, prepared from the following components in parts by weight:

[0006] 100 parts of base bitumen;

[0007] 1 to 5 parts of softening oil; said softening oil includes aromatic oil, oleic acid, furfural extract oil and wax oil;

[0008] 15-30 parts of micro-nano rubber particles; said micro-nano rubber particles are obtained from desulfurized and activated reclaimed rubber;

[0009] 0.1 to 0.3 parts of stabilizer;

[0010] 0 to 3 parts of high molecular weight polymer.

[0011] Preferably, the environmentally friendly rubber-modified asphalt is prepared from the following components in parts by weight:

[0012] 100 parts of base bitumen;

[0013] 1 to 2 parts softening oil;

[0014] 15-30 parts of micro-nano rubber particles;

[0015] 0.25 to 0.3 parts of stabilizer;

[0016] 1 to 3 parts of polymer.

[0017] The softening oil of this invention comprises aromatic oil, oleic acid, furfural extract oil, and wax oil in a mass ratio of (68-72):(2.5-3.5):(11-13):(14-16), preferably comprising aromatic oil, oleic acid, furfural extract oil, and wax oil in a mass ratio of 70:3:12:15; wherein the aromatic oil contains 50%-65% aromatic components and 10%-25% saturated components; the wax oil is vacuum-pressed second-line oil and vacuum-pressed third-line oil. The softening oil of this invention is prepared by uniformly mixing aromatic oil, oleic acid, furfural extract oil, and wax oil in a specific ratio based on the principle of "like dissolves like".

[0018] The micro-nano rubber particles of this invention are obtained from desulfurized and activated reclaimed rubber, exhibiting lower odor and superior low-temperature performance. Specifically, they are prepared by the following method: Microwave pre-desulfurization treatment is performed on waste tire rubber powder; the microwave pre-desulfurized waste tire rubber powder, along with a desulfurization aid and rubber oil, undergoes a melt extrusion desulfurization reaction to obtain micro-nano rubber particles. More specifically, the waste tire rubber powder undergoes microwave pre-desulfurization treatment; the microwave pre-desulfurized waste tire rubber powder, along with a desulfurization aid and rubber oil, is stirred and mixed evenly, and then subjected to a melt extrusion desulfurization reaction through a twin-screw extruder. The resulting extrudate is the desulfurized and activated reclaimed rubber, which is further cooled with water and pelletized to obtain micro-nano rubber particles. The melt extrusion desulfurization reaction temperature of this invention is 180℃~190℃; the melt extrusion desulfurization reaction is carried out by screw extrusion, with the screw speed being 88r / min~112r / min.

[0019] The penetration of the base asphalt described in this invention is 60 dmm to 80 dmm. In some embodiments of this invention, the base asphalt is selected from 70# road petroleum asphalt (70# is based on a penetration grading system, with a penetration of 60 dmm to 80 dmm).

[0020] The main component of the stabilizer described in this invention is sulfur; the main function of the stabilizer described in this invention is to form a network structure in the asphalt, thereby increasing the thermal stability and toughness of the asphalt.

[0021] The polymer described in this invention may be selectively added or not added, and is selected from one or more of styrene-butadiene-styrene triblock copolymers, styrene-butadiene rubber and natural rubber, preferably styrene-butadiene-styrene triblock copolymers (SBS), and more preferably linear styrene-butadiene-styrene triblock copolymers.

[0022] The environmentally friendly rubber asphalt provided by this invention has good stability. The softening oil in the formula not only acts as a solubilizer for asphalt, but also, through the synergistic effect of the softening oil and micro-nano rubber particles with other components, improves the odor of traditional rubber-modified asphalt, reduces product costs, and enhances the overall performance of the rubber asphalt. Specifically, it improves the high and low temperature performance of traditional rubber-modified asphalt, exhibiting excellent high and low temperature performance, especially with a low-temperature brittle point above -25℃.

[0023] The present invention also provides a method for preparing environmentally friendly rubber-modified asphalt according to any of the above technical solutions, comprising the following steps: mixing and stirring base asphalt, softening oil, micro-nano rubber particles and optional polymer, grinding with a colloid mill, and then adding a stabilizer and stirring to obtain environmentally friendly rubber-modified asphalt.

[0024] Specifically, the base asphalt is first heated to 160℃~170℃, then softening oil is added and stirred evenly to obtain mixture A; micro-nano rubber particles are added to mixture A and stirred to swell, obtaining mixture B; a optionally selected polymer is added to mixture B, stirred evenly, and heated to 175℃~185℃ for colloid milling to obtain mixture C; a stabilizer is added to mixture C and stirred for development to obtain environmentally friendly rubber-modified asphalt. The stirring and development temperature in this invention is 180℃~185℃, preferably 183℃; the stirring and development time is 5h~10h; and the stirring rate is 400r / min~600r / min. The base asphalt, softening oil, micro-nano rubber particles, and polymer in this invention are the same as described above and will not be repeated.

[0025] The present invention also provides the application of environmentally friendly rubber-modified asphalt as described in any of the above technical solutions or the preparation method of environmentally friendly rubber-modified asphalt as described in any of the above technical solutions as road construction material.

[0026] This invention provides an environmentally friendly rubber-modified asphalt, its preparation method, and its application. The environmentally friendly rubber-modified asphalt of this invention is prepared from the following components in parts by weight: 100 parts of base asphalt; 1-5 parts of softening oil; the softening oil includes aromatic oil, oleic acid, furfural extract oil, and wax oil; 15-30 parts of micro-nano rubber particles; the micro-nano rubber particles are obtained from desulfurized and activated reclaimed rubber; 0.1-0.3 parts of stabilizer; and 0-3 parts of polymer. Compared with ordinary rubber-modified asphalt, the environmentally friendly rubber-modified asphalt of this invention has higher viscosity, excellent low-temperature performance, and excellent high-temperature performance, ensuring better high and low temperature performance of the pavement after application. The system is stable, significantly reducing odor during construction, and is environmentally friendly. This invention uses an environmentally friendly rubber particle wet process to prepare environmentally friendly rubber asphalt, which can be mass-produced using conventional modified asphalt production processes. The preparation process is simple, requiring only one feeding and a colloid mill to obtain high-grade modified asphalt, saving production costs. Detailed Implementation

[0027] This invention discloses an environmentally friendly rubber-modified asphalt, its preparation method, and its application. Those skilled in the art can refer to the content of this document and appropriately modify the process parameters to achieve the desired result. It should be particularly noted that all similar substitutions and modifications are obvious to those skilled in the art and are considered to be included in this invention. The method and application of this invention have been described through preferred embodiments, and those skilled in the art can clearly modify or appropriately change and combine the method and application described herein without departing from the content, spirit, and scope of this invention to realize and apply the technology of this invention.

[0028] In the environmentally friendly rubber-modified asphalt prepared in the specific embodiments of the present invention, the base asphalt is base asphalt 70#;

[0029] The polymer is styrene-butadiene-styrene triblock copolymer (SBS);

[0030] The softening oil is composed of aromatic oil, oleic acid, furfural extract oil, and wax oil in a mass ratio of 70:3:12:15; wherein the aromatic oil has an aromatic content of 50%–65% and a saturation content of 10%–25%; and the wax oil is vacuum-pressed second-line oil and vacuum-pressed third-line oil. It is prepared by uniformly mixing aromatic oil, oleic acid, furfural extract oil, and wax oil in a specific ratio based on the principle of "like dissolves like".

[0031] The micro-nano rubber particles are rubber particles prepared from desulfurized and activated reclaimed rubber, with lower odor and superior low-temperature performance. The preparation method is as follows: waste tire rubber powder is spread evenly in a microwave ceramic dish, and the dish is placed in a microwave reactor for microwave pre-desulfurization treatment; the microwave-treated waste tire rubber powder is mixed evenly with desulfurization additives and rubber oil, and then added to a twin-screw extruder for melt extrusion desulfurization reaction. The extrudate is water-cooled and pelletized to obtain desulfurized rubber powder particles, which are then desulfurized through screw extrusion at a desulfurization temperature of 185℃ and a screw speed of 100 r / min.

[0032] The stabilizer, whose main component is sulfur, mainly forms a network structure within the asphalt, increasing the thermal stability and toughness of the asphalt.

[0033] The present invention will be further described below with reference to the embodiments:

[0034] Example 1

[0035] Step 1: Heat the base asphalt 70# to 165℃, then add 2% softening oil and stir well;

[0036] Step 2: Add 20% micro-nano rubber particles and stir evenly, then add 2% SBS, stir evenly, and continue heating to 180℃ for colloid milling.

[0037] Step 3: After grinding, add 0.3% stabilizer and carry out development to obtain environmentally friendly rubber-modified asphalt; development temperature 183℃, development time 8h, stirring rate 450r / min.

[0038] Comparative Example 1

[0039] Step 1: Heat the base asphalt 70# to 165℃, add 20% 40-mesh vulcanized rubber powder, stir evenly, and continue heating to 180℃ for colloid milling.

[0040] Step 2: After grinding, add 0.3% stabilizer and carry out development to obtain asphalt; development temperature 183℃, development time 8h, stirring rate 450r / min.

[0041] Example 2

[0042] Step 1: Heat the base asphalt 70# to 165℃, then add 1.5% softening oil and stir well;

[0043] Step 2: Add 15% micro-nano rubber particles and stir evenly, then add 3% SBS, stir evenly, and continue heating to 180℃ for colloid milling.

[0044] Step 3: After grinding, add 0.25% stabilizer and carry out development to obtain environmentally friendly rubber-modified asphalt; development temperature 183℃, development time 8h, stirring rate 450r / min.

[0045] Example 3

[0046] Step 1: Heat the base asphalt 70# to 165℃, then add 2% softening oil and stir well;

[0047] Step 2: Add 30% micro-nano rubber particles and stir evenly, then add 1% SBS, stir evenly, and continue heating to 180℃ for colloid milling.

[0048] Step 3: After grinding, add 0.25% stabilizer and carry out development to obtain environmentally friendly rubber-modified asphalt; development temperature 183℃, development time 8h, stirring rate 450r / min.

[0049] Comparative Example 2

[0050] Step 1: Heat the base asphalt 70# to 165℃, then add 1.5% co-solvent (common modified asphalt co-solvent purchased from the market), and stir evenly;

[0051] Step 2: Add 15% micro-nano rubber particles and stir evenly, then add 3% SBS, stir evenly, and continue heating to 180℃ for colloid milling.

[0052] Step 3: After grinding, add 0.25% stabilizer and carry out development to obtain environmentally friendly rubber-modified asphalt; development temperature 183℃, development time 8h, stirring rate 450r / min.

[0053] The asphalt indices obtained from the above embodiments and comparative examples are shown in Table 1:

[0054] Table 1

[0055]

[0056] As shown in Table 1, the rubber-modified asphalt of this invention has excellent high-temperature performance and low-temperature crack resistance compared with ordinary rubber-modified asphalt. Moreover, the preparation process is simple. It adopts the conventional modified asphalt production process, and the rubber-modified asphalt can be obtained by one feeding and grinding with a colloid mill. According to environmental protection index testing, the release of harmful gases is reduced, and the odor during the road paving process is reduced.

[0057] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. An environmentally friendly rubber-modified asphalt, characterized in that, Prepared from the following components in parts by weight: 100 parts of base bitumen; 1-5 parts of softening oil; the softening oil comprising aromatic oil, oleic acid, furfural extract oil and wax oil in a mass ratio of (68-72):(2.5-3.5):(11-13):(14-16); the aromatic oil having an aromatic content of 50%-65% and a saturation content of 10%-25%; the wax oil comprising asphalt vacuum distillation second-line oil and asphalt vacuum distillation third-line oil; 15-30 parts of micro-nano rubber particles; the micro-nano rubber particles are obtained from desulfurized and activated reclaimed rubber; 0.1 to 0.3 parts of stabilizer; 1 to 3 parts of a polymer, wherein the polymer is selected from styrene-butadiene-styrene triblock copolymer.

2. The environmentally friendly rubber-modified asphalt according to claim 1, characterized in that, Prepared from the following components in parts by weight: 100 parts of base bitumen; 1-2 parts softening oil; 15-30 parts of micro-nano rubber particles; 0.25~0.3 parts of stabilizer; 1 to 3 parts of polymer.

3. The environmentally friendly rubber-modified asphalt according to claim 1 or 2, characterized in that, Micro-nano rubber particles are prepared by the following method: Waste tire rubber powder is subjected to microwave pre-desulfurization treatment; the waste tire rubber powder after microwave pre-desulfurization treatment is then subjected to melt extrusion desulfurization reaction with desulfurization additives and rubber oil to obtain desulfurized rubber powder particles.

4. The environmentally friendly rubber-modified asphalt according to claim 3, characterized in that, The temperature of the melt extrusion desulfurization reaction is 180℃~190℃; The melt extrusion desulfurization reaction is carried out by screw extrusion, and the screw speed is 88 r / min~112 r / min.

5. The environmentally friendly rubber-modified asphalt according to claim 1 or 2, characterized in that, The penetration of the base bitumen is 60 dmm to 80 dmm; The stabilizer includes sulfur.

6. The method for preparing environmentally friendly rubber-modified asphalt according to any one of claims 1 to 5, characterized in that, Includes the following steps: The base asphalt, softening oil, micro-nano rubber particles and polymer are mixed and stirred, then ground in a colloid mill. A stabilizer is then added and stirred to develop the mixture, resulting in environmentally friendly rubber-modified asphalt.

7. The preparation method according to claim 6, characterized in that, The stirring development temperature is 180℃~185℃, the stirring development time is 5 h~10 h, and the stirring rate is 400 r / min~600 r / min.

8. The application of the environmentally friendly rubber-modified asphalt prepared by any of the methods described in claims 1 to 5 or any of the methods described in claims 6 to 7 as a road construction material.

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