CN114716835A - High-performance asphalt warm-mixing agent and preparation method and application thereof - Google Patents
High-performance asphalt warm-mixing agent and preparation method and application thereof Download PDFInfo
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- CN114716835A CN114716835A CN202210405534.7A CN202210405534A CN114716835A CN 114716835 A CN114716835 A CN 114716835A CN 202210405534 A CN202210405534 A CN 202210405534A CN 114716835 A CN114716835 A CN 114716835A
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L95/00—Compositions of bituminous materials, e.g. asphalt, tar, pitch
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L2201/00—Properties
- C08L2201/08—Stabilised against heat, light or radiation or oxydation
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
- Y02A30/00—Adapting or protecting infrastructure or their operation
- Y02A30/30—Adapting or protecting infrastructure or their operation in transportation, e.g. on roads, waterways or railways
Abstract
The invention relates to the technical field of materials for road engineering, in particular to a high-performance asphalt warm-mixing agent and a preparation method and application thereof. The high-performance asphalt warm-mixing agent is prepared from the following raw materials in parts by weight: 10-20 parts of aromatic oil and 5-10 parts of waste plastic cracking wax. According to the invention, the asphalt warm-mixing agent is prepared by adopting a mode of matching aromatic oil with waste plastic cracked paraffin, the mixing temperature of asphalt can be effectively reduced by 41-46 ℃, and the softening point can not be obviously reduced on the premise of improving the penetration of asphalt. And the high-temperature stability is extremely excellent, which shows that the deformation of the road surface is very small when the road passes through wheels at a high temperature, namely the road surface still has good performance of resisting track diseases in summer.
Description
Technical Field
The invention relates to the technical field of materials for road engineering, in particular to a high-performance asphalt warm-mixing agent and a preparation method and application thereof.
Background
The warm-mix asphalt mixture is an asphalt mixture which reduces the production and paving temperature of the warm-mix asphalt mixture through a certain process and ensures that the performance of the warm-mix asphalt mixture reaches the standard of the warm-mix asphalt mixture. Compared with a hot-mix asphalt mixture, the warm-mix asphalt mixture can reduce energy consumption and harmful gas emission in the production process; compared with a cold-mix asphalt mixture, the problems of low initial strength, poor road performance and the like of the asphalt mixture can be avoided.
The current methods for producing warm mix asphalt mixtures include the following three methods: 1) the foam is mainly based on the technical principle of foaming asphalt, water is directly injected into hot asphalt, and the viscosity of the asphalt is reduced through rapid vaporization and foaming of the water, so that the construction temperature of the mixture is reduced. 2) Organic additives mainly change the viscosity-temperature relationship of asphalt through organic matters or wax, and the Sasobit commonly used in China at present belongs to the technology. 3) Chemical additives, most commonly emulsifiers, surfactants, etc., are used to improve the fluidity of asphalt at lower temperatures. However, most warm-mix agents have an impact on the asphalt properties, since lowering the mixing temperature results in a lowering of the aggregate heating temperature, which in turn has an impact on the mix's adhesion.
Therefore, it is an urgent technical problem to be solved by those skilled in the art to provide a high-performance warm mixing agent and to reduce the mixing temperature without affecting the performance of the asphalt mixture.
Disclosure of Invention
The invention aims to provide a high-performance asphalt warm-mixing agent and a preparation method and application thereof.
In order to achieve the above object, the present invention provides the following technical solutions:
the invention provides a high-performance asphalt warm-mixing agent which is prepared from the following raw materials in parts by weight: 10-20 parts of aromatic oil and 5-10 parts of waste plastic cracking wax.
Preferably, the aromatic hydrocarbon oil contains 75-85% of aromatic hydrocarbon, less than or equal to 0.5% of asphalt olefin and the balance saturated hydrocarbon.
Preferably, the waste plastic cracking wax is obtained by mixing waste high-density polyethylene plastic and waste low-density polyethylene plastic according to the mass ratio of 2-3: 1 and then cracking the mixture in a nitrogen atmosphere.
Preferably, the cracking temperature is 310-330 ℃, and the cracking time is 0.6-0.8 h.
The invention also provides a preparation method of the high-performance asphalt warm-mixing agent, which is characterized by comprising the following steps of:
mixing aromatic oil and waste plastic cracking wax to obtain the high-performance asphalt warm-mixing agent.
Preferably, the mixing temperature is 90-110 ℃.
Preferably, the mixing is carried out under the stirring condition, the stirring rotating speed is 400-600 r/min, and the stirring time is 10-20 min.
The invention also provides an application method of the high-performance asphalt warm-mixing agent in preparation of warm-mixing asphalt.
Through the technical scheme, compared with the prior art, the invention has the following beneficial effects:
according to the invention, the asphalt warm-mixing agent is prepared by adopting the matching mode of aromatic oil and waste plastic cracking wax, so that the mixing temperature of asphalt can be reduced by 41-46 ℃, and the softening point can not be obviously reduced on the premise of improving the penetration of asphalt. In addition, the asphalt warm-mixing agent has extremely excellent high-temperature stability, and the deformation of the road surface is very small when the vehicle wheel passes through the warm-mixing agent at a higher temperature, namely the warm-mixing agent enables the road surface to have good performance of resisting track diseases in summer.
Detailed Description
The invention provides a high-performance asphalt warm-mixing agent which is prepared from the following raw materials in parts by weight: 10-20 parts of aromatic oil, 5-10 parts of waste plastic cracking wax, preferably 12-16 parts of aromatic oil and 6-9 parts of waste plastic cracking wax.
In the invention, preferably, the aromatic hydrocarbon content in the aromatic oil is 75-85%, preferably 80-85%, the asphalt olefin content is less than or equal to 0.5%, preferably less than or equal to 0.4%, and the balance is saturated hydrocarbon.
In the invention, the waste plastic cracking wax is obtained by mixing waste high-density polyethylene plastic and waste low-density polyethylene plastic according to the mass ratio of 2-3: 1 and then cracking the mixture in a nitrogen atmosphere.
In the invention, the waste high-density polyethylene plastic is a waste high-density polyethylene plastic bottle, and the waste low-density polyethylene plastic is a waste low-density polyethylene plastic bag, which is provided for sanitation in Shanxi jin.
In the invention, the waste high-density polyethylene plastic and the waste low-density polyethylene plastic are crushed to 2-4 mm, preferably 2.5-3.5 mm before cracking.
In the invention, the cracking temperature is 310-330 ℃, preferably 310-320 ℃, and the cracking time is 0.6-0.8 h, preferably 0.6-0.7 h.
The invention also provides a preparation method of the high-performance asphalt warm-mixing agent, which is characterized by comprising the following steps of:
mixing aromatic oil and waste plastic cracking wax to obtain the high-performance asphalt warm-mixing agent.
In the present invention, the mixing temperature is 90 to 110 ℃, preferably 95 to 105 ℃.
In the invention, the mixing is carried out under the stirring condition, the stirring speed is 400-600 r/min, preferably 450-550 r/min, and the stirring time is 10-20 min, preferably 12-18 min.
The invention also provides an application of the high-performance asphalt warm-mixing agent in preparation of warm-mixing asphalt.
In the invention, when the high-performance asphalt warm-mixing agent is used for preparing warm-mixing asphalt, the specific asphalt is 90# asphalt.
In the invention, the mixing amount of the high-performance asphalt warm-mixing agent in the preparation of the warm-mixing asphalt is 5-8% of the mass of the asphalt.
The technical solutions provided by the present invention will be described in detail with reference to the following examples, but they should not be construed as limiting the scope of the present invention, and all of the "parts" in the examples of the present invention are "parts by weight", and the waste high density polyethylene plastic bottles and waste low density polyethylene plastic bags used in the examples of the present invention are provided for sanitation in shanxi.
Example 1
Crushing the waste high-density polyethylene plastic bottles and the waste low-density polyethylene plastic bags to the particle size of 2mm, mixing according to the mass ratio of 2:1, heating to 310 ℃ at the speed of 11 ℃/min in a nitrogen atmosphere, and cracking for 0.6h to obtain waste plastic cracking wax;
heating 10 parts of aromatic oil (the aromatic hydrocarbon content is 75%, the asphalt olefin content is 0.5%, and the balance is saturated hydrocarbon) to 95 ℃, adding 5 parts of waste plastic cracking wax, and stirring at the rotating speed of 455r/min for 12min to obtain the high-performance asphalt warm-mixing agent.
Example 2
Crushing waste high-density polyethylene plastic bottles and waste low-density polyethylene plastic bags to the particle size of 3mm, mixing according to the mass ratio of 2.3:1, heating to 320 ℃ at the speed of 13 ℃/min in a nitrogen atmosphere, and cracking for 0.7h to obtain waste plastic cracked wax;
heating 15 parts of aromatic oil (the content of aromatic hydrocarbon is 80%, the content of asphalt olefin is 0.3%, and the balance is saturated hydrocarbon) to 100 ℃, then adding 7 parts of waste plastic cracking wax, and stirring at the rotating speed of 500r/min for 15min to obtain the high-performance asphalt warm-mixing agent.
Example 3
Crushing the waste high-density polyethylene plastic bottles and the waste low-density polyethylene plastic bags to the particle size of 4mm, mixing according to the mass ratio of 3:1, heating to 330 ℃ at the speed of 15 ℃/min in a nitrogen atmosphere, and cracking for 0.8h to obtain waste plastic cracking wax;
heating 20 parts of aromatic oil (the aromatic hydrocarbon content is 85%, the asphalt olefin content is 0.4%, and the balance is saturated hydrocarbon) to 110 ℃, adding 10 parts of waste plastic cracking wax, and stirring at the rotating speed of 550r/min for 20min to obtain the high-performance asphalt warm-mixing agent.
Comparative example 1
Comparative example 1 differs from example 2 in that the composition does not contain waste plastic cracking wax.
Comparative example 2
Comparative example 2 is different from example 2 in that the composition thereof does not contain an aromatic oil.
Comparative example 3
The difference between the comparative example 3 and the example 2 is that the mass ratio of the waste high-density polyethylene plastic to the waste low-density polyethylene plastic in the used waste plastic cracking wax is 5: 1.
heating 90# asphalt to 100 ℃, then respectively adding the asphalt warm-mixing agents prepared in the examples 1-3 and the comparative examples 1-3, and obtaining the modified asphalt after the asphalt warm-mixing agents are completely dissolved in the asphalt under the stirring condition.
Index tests are carried out according to test procedures for road asphalt and asphalt mixtures (JTG E20-2011), and specific results of the influence of the warm-mixing agent on the performance of asphalt are shown in Table 1;
TABLE 1 influence of warm asphalt mixing agents obtained in examples 1 to 3 and comparative examples 1 to 3 on the performance of base asphalt
As can be seen from Table 1, the high-performance warm asphalt mixing agents prepared in the embodiments 1 to 3 can effectively improve the penetration degree of asphalt, and the effect of the warm asphalt mixing agents obtained in the comparative examples 1 to 3 on the improvement of the penetration degree of asphalt is not obvious; and the results of the 10 ℃ ductility test show that compared with the warm-mix agents prepared in the examples 1 to 3, the asphalt warm-mix agents obtained in the comparative examples 1 to 3 have larger difference in test results, and have limited improvement results on the low-temperature performance of the matrix asphalt; the use of the asphalt warm-mixing agent can reduce the softening point of the matrix asphalt, and the asphalt warm-mixing agent obtained in the comparative examples 1-2 can cause the softening point of the asphalt to be not in accordance with the technical indexes of the asphalt after being added into the asphalt.
Modified asphalts obtained by blending asphalt with the warm asphalt mixing agents of examples 1 to 3 and comparative examples 1 to 3 were subjected to a marshall test (note that the amount of each warm asphalt mixing agent is shown in table 1), wherein the oilstone ratio is 4%, the particle size distribution of the ore powder is AC-25 type, and the specific test results are shown in table 2.
TABLE 2 results of determination of modified asphalts obtained in examples 1 to 3 and comparative examples 1 to 3 by Marshall test
The void ratio has obvious influence on the service performance of the pavement, and if the void ratio is unqualified, diseases such as water damage, cracking and the like are followed. If the temperature in the compaction process does not meet the specification, the workability of the asphalt mixture does not reach the standard, the mixture is difficult to compact, the void ratio is seriously unqualified, and the test data in the table 2 show that the asphalt warm-mixing agent prepared by the invention reduces the asphalt mixing temperature by 41-46 ℃.
The mixture obtained by performing the marshall test on the modified asphalt obtained by doping the asphalt warm-mix agents of examples 1 to 3 and comparative examples 1 to 3 with asphalt is subjected to a high-temperature stability test, the high-temperature stability test adopts an asphalt mixture rutting test, and specific test results are shown in table 3.
TABLE 3 results of rutting test of modified asphalt mixtures obtained in examples 1 to 3 and comparative examples 1 to 3
As can be seen from table 3, the mixture prepared from the modified asphalt obtained by blending the asphalt warm-mix agent of embodiments 1 to 3 of the present invention with asphalt has extremely excellent high-temperature stability, which indicates that the road surface has very little deformation when passing through a wheel at a higher temperature, i.e., the road surface still has very good performance of resisting track diseases in summer.
The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.
Claims (8)
1. The high-performance asphalt warm-mixing agent is characterized by being prepared from the following raw materials in parts by weight: 10-20 parts of aromatic oil and 5-10 parts of waste plastic cracking wax.
2. The high-performance asphalt warm-mixing agent as claimed in claim 1, wherein the aromatic oil contains 75-85% of aromatic hydrocarbon, the asphalt olefin content is less than or equal to 0.5%, and the balance is saturated hydrocarbon.
3. The high-performance asphalt warm-mixing agent as claimed in claim 1 or 2, wherein the waste plastic cracking wax is obtained by mixing waste high-density polyethylene plastic and waste low-density polyethylene plastic according to a mass ratio of 2-3: 1, and cracking the mixture in a nitrogen atmosphere.
4. The high-performance asphalt warm-mixing agent as claimed in claim 3, wherein the cracking temperature is 310-330 ℃ and the cracking time is 0.6-0.8 h.
5. The preparation method of the high-performance asphalt warm-mixing agent as claimed in any one of claims 1 to 4, characterized by comprising the following steps:
mixing aromatic oil and waste plastic cracking wax to obtain the high-performance asphalt warm-mixing agent.
6. The method according to claim 5, wherein the mixing temperature is 90 to 110 ℃.
7. The method according to claim 5 or 6, wherein the mixing is carried out under stirring conditions, wherein the stirring speed is 400 to 600r/min, and the stirring time is 10 to 20 min.
8. The use of the high-performance asphalt warm-mixing agent as defined in any one of claims 1 to 4 in the preparation of warm-mixed asphalt.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116200207A (en) * | 2023-02-01 | 2023-06-02 | 合肥工业大学 | Integrated preparation system and method for waste plastic modified asphalt mixture |
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Cited By (1)
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| CN116200207A (en) * | 2023-02-01 | 2023-06-02 | 合肥工业大学 | Integrated preparation system and method for waste plastic modified asphalt mixture |
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Inventor after: Xie Xiaofeng Inventor after: Cai Xiao Inventor after: Chen Mingjin Inventor after: Sun Longhua Inventor after: Huang Jiaojiao Inventor after: Shen Ligang Inventor after: Zhang Zefeng Inventor after: Dang Xueping Inventor after: Sun Yichun Inventor after: Li Yingjie Inventor after: Duan Jiubo Inventor after: Fan Lizhi Inventor after: Fu Zhongyang Inventor after: Zheng Kangyu Inventor after: Feng Li Inventor after: Zhou Qiulai Inventor before: Duan Jiubo Inventor before: Chen Mingjin Inventor before: Sun Longhua Inventor before: Huang Jiaojiao Inventor before: Shen Ligang Inventor before: Zhang Zefeng Inventor before: Dang Xueping Inventor before: Fan Lizhi Inventor before: Fu Zhongyang Inventor before: Xie Xiaofeng Inventor before: Li Yingjie Inventor before: Zheng Kangyu Inventor before: Feng Li Inventor before: Zhou Qiulai Inventor before: Cai Xiao |
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