CN117466575A

CN117466575A - Preparation method of low-carbon recycling modified asphalt mixture

Info

Publication number: CN117466575A
Application number: CN202311831779.7A
Authority: CN
Inventors: 刘永伟; 张楠楠; 王志起; 李成江; 彭仕军; 杨光勋
Original assignee: Tianrun Tianfu New Material Co ltd
Current assignee: Tianrun Tianfu New Material Co ltd
Priority date: 2023-12-28
Filing date: 2023-12-28
Publication date: 2024-01-30
Anticipated expiration: 2043-12-28
Also published as: CN117466575B

Abstract

The application discloses a preparation method of a low-carbon recycling modified asphalt mixture, and relates to the technical field of asphalt. The method comprises the following steps: crushing the waste SBS mixture, and then performing thermal cracking to obtain a thermal cracking product; asphalt stripping is carried out on the thermal cracking products to obtain old SBS modified asphalt and old mineral aggregate; heating and mixing the old SBS modified asphalt and the matrix asphalt, adding an SBS modifier, stirring, adding a regenerant, shearing and mixing, adding a regenerated crosslinking agent, stirring, and performing heat preservation development to obtain an intermediate product; adding a plasticizing softener and a warm mixing agent into the intermediate product, and shearing and mixing to obtain an asphalt base material; and adding old mineral aggregate and filling powder into the asphalt base material, and heating and stirring to obtain the finished asphalt mixture. The method can reduce the mixing temperature while ensuring the mixing uniformity and road performance of the reclaimed materials, thereby realizing low carbon, and the reclaimed asphalt mixture has better high-low temperature performance.

Description

Preparation method of low-carbon recycling modified asphalt mixture

Technical Field

The application relates to the technical field of asphalt, in particular to a preparation method of a low-carbon recycling modified asphalt mixture.

Background

The recycling of the modified asphalt mixture realizes the regeneration of the waste modified asphalt mixture, and the waste modified asphalt mixture is a mixture which is prepared by digging, recycling, crushing and screening waste asphalt pavement, and then re-mixing the waste asphalt pavement with a regenerant, new asphalt materials, new aggregates and the like according to a certain proportion. In the production process of the asphalt mixture, the mixing temperature of 100 ℃ can be reduced by 25-30% compared with the energy source, and the carbon emission can be reduced to a certain extent. Therefore, in the regeneration process of the waste modified asphalt mixture, if the mixing uniformity and the road performance of the regenerated material can be ensured, and the mixing temperature is reduced, the method is an effective way for realizing low carbon. However, compared with the common matrix asphalt, the aging degree of the modified asphalt is not only related to the aging of the matrix asphalt, but also depends on the aging degradation of the modifier to a great extent, and in the regeneration process of the waste modified asphalt mixture, the aged asphalt performance is not recovered while the modified asphalt is repaired, and when the mixing temperature is reduced, the fluidity of the asphalt is poor, so that the contact and mixing performance of the asphalt with other modified agents are poor, and the road performance of the regenerated asphalt mixture is poor.

Disclosure of Invention

The main purpose of the application is to provide a preparation method of a low-carbon recycling modified asphalt mixture, which aims to solve the technical problem of poor road performance of the existing regenerated modified asphalt mixture.

In order to achieve the above purpose, the application provides a preparation method of a low-carbon recycling modified asphalt mixture, which comprises the following steps:

crushing the waste SBS mixture, and then performing thermal cracking to obtain a thermal cracking product;

asphalt stripping is carried out on the thermal cracking products to obtain old SBS modified asphalt and old mineral aggregate;

heating and mixing the old SBS modified asphalt and the matrix asphalt, adding an SBS modifier, stirring, adding a regenerant, shearing and mixing, adding a regenerated crosslinking agent, stirring, and performing heat preservation development to obtain an intermediate product;

adding a plasticizing softener and a warm mixing agent into the intermediate product, and shearing and mixing to obtain an asphalt base material;

and adding the old mineral aggregate and the filling powder into the asphalt base material, and heating and stirring to obtain a finished asphalt mixture.

Optionally, in the step of performing thermal cracking, the thermal cracking temperature is 240-260 ℃ and the thermal cracking time is 15-25 min.

Optionally, the regenerant comprises the following raw materials in parts by weight: 30-50 parts of plant asphalt, 25-45 parts of epoxidized soybean oil, 15-30 parts of diallyl phthalate, 10-20 parts of polyphosphate and 5-15 parts of nano silicon dioxide.

Optionally, the regenerated cross-linking agent is an epoxy group-containing compound.

Optionally, the chemical structural formula of the regenerated cross-linking agent is:

。

optionally, after heating and mixing the old SBS modified asphalt and the matrix asphalt, adding an SBS modifier, stirring, adding a regenerant, shearing and mixing, adding a regenerated crosslinking agent, stirring, and performing heat preservation development to obtain an intermediate product, wherein the method comprises the following steps of:

mixing the old SBS modified asphalt with matrix asphalt at 130-150 ℃ for 25-35 min, adding SBS modifier for several times, continuously stirring, adding a regenerant, shearing and mixing at a shearing rate of 2500-3500 rpm for 40-50 min, adding a regenerated cross-linking agent, stirring, and developing at 130-150 ℃ for 1.5-2.5 h to obtain an intermediate product.

Optionally, the warm mix agent comprises the following raw materials in parts by weight: 30-40 parts of cetyl trimethyl ammonium chloride, 20-30 parts of polyethylene wax and 5-10 parts of polyalcohol.

Optionally, the plasticizing softener includes cracked petroleum byproducts.

Optionally, the step of adding the old mineral aggregate and the filling powder into the asphalt base material, heating and stirring to obtain a finished asphalt mixture comprises the following steps:

adding the old mineral aggregate and limestone mineral powder into the asphalt base material, and stirring and mixing at 120-130 ℃ to obtain the finished asphalt mixture.

Firstly, crushing and then thermally cracking the waste SBS mixture, wherein the waste SBS mixture contains aged matrix asphalt, SBS modifier, stone, mineral powder and some adhered oily sludge, and the oily sludge can be cracked through thermal cracking so as to facilitate subsequent asphalt stripping; the new asphalt and the SBS modifier are added into the old SBS modified asphalt for regeneration, the SBS modifier and the old SBS modified asphalt are similar in composition, the SBS modifier and the old SBS modified asphalt are promoted to be compatible, the residual SBS in the old asphalt and the newly added SBS can be fully swelled in the regenerant, after the regenerant and the aged asphalt are subjected to a crosslinking reaction, the aged asphalt can be restored into a network structure which is mutually wound, the effect of regenerating the aged asphalt is achieved, the components of the new asphalt are adjusted to unbalanced components of the aged asphalt by adding the new asphalt and the SBS modifier, the aged asphalt is regenerated, the SBS modifier utilizes the good swelling decomposition capacity of the new asphalt in the regenerated asphalt, and the stable asphalt colloid structure reconstructed by the regenerant is promoted, so that the aged asphalt can be regenerated into the modified asphalt, and the regenerated asphalt can be secondarily modified to become the secondary modified asphalt; because the SBS modifier is degraded and aged in addition to the matrix asphalt in the old SBS modified asphalt, and the SBS molecular chain segments are broken into two SB molecular chain segments, the SBS modifier with broken chain is recovered by adding the regenerated cross-linking agent, so that the effect of synchronous regeneration is achieved; and then plasticizing softener and warm mixing agent are added to improve the flexibility and rheological property of the system, reduce the viscosity of asphalt, ensure the contact and mixing uniformity with other modifiers, achieve the effect of warm mixing, and finally prepare asphalt mixture by taking old mineral aggregate and filling powder as filling materials. The method realizes the recycling of the waste SBS modified asphalt mixture, ensures the mixing uniformity and road performance of the reclaimed materials, and simultaneously reduces the mixing temperature, thereby realizing low carbon, and the obtained reclaimed asphalt mixture has better high-low temperature performance and can meet the use requirement in road performance.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings that are required in the embodiments or the description of the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and that other drawings may be obtained from the structures shown in these drawings without inventive effort to a person of ordinary skill in the art.

FIG. 1 is a schematic view of the dynamic stability of an asphalt mixture according to an embodiment of the present application.

The realization, functional characteristics and advantages of the present application will be further described with reference to the embodiments, referring to the attached drawings.

Detailed Description

The following description of the embodiments of the present application will be made clearly and fully with reference to the accompanying drawings, in which it is evident that the embodiments described are only some, but not all, of the embodiments of the present application. All other embodiments, which can be made by one of ordinary skill in the art based on the embodiments herein without making any inventive effort, are intended to be within the scope of the present application.

Aiming at the technical problems existing in the prior art, the embodiment of the application provides a preparation method of a low-carbon recycling modified asphalt mixture, which comprises the following steps:

As an implementation mode of the method, in the step of performing thermal cracking, the thermal cracking temperature is 240-260 ℃ and the thermal cracking time is 15-25 min.

Thermal cracking for 15-25 min at 240-260 ℃ to crack some oily sludge adhered to the waste SBS mixture, and stripping asphalt later so as to strip the old SBS modified asphalt and the old mineral aggregate and then regenerating the old SBS modified asphalt.

As an embodiment of the present application, the raw materials of the regenerant include, in parts by weight: 30-50 parts of plant asphalt, 25-45 parts of epoxidized soybean oil, 15-30 parts of diallyl phthalate, 10-20 parts of polyphosphate and 5-15 parts of nano silicon dioxide.

According to the method, vegetable asphalt, epoxidized soybean oil and diallyl phthalate are taken as softening systems, the vegetable asphalt is asphaltene extracted from plants, the vegetable asphalt is a byproduct obtained in the production process of rectifying vegetable oil, the main components of the vegetable asphalt are 60% -80% of fatty acid and vegetable alcohol, the vegetable asphalt has chemical components similar to asphalt, the epoxidized soybean oil is linoleic acid, oleic acid, palmitic acid and the like, the dispersing effect of the vegetable asphalt in the asphalt is good, the effect of rapidly dispersing and recovering the characteristics of aged asphalt can be achieved, the diallyl phthalate can be used for supplementing the volatilized light components of the aged asphalt, the softening systems can soften the aged asphalt and dissolve the asphaltene, the polyphosphate can be taken as a dispersion stabilizer, so that asphaltene particles are well dispersed, the miscibility of new and old asphalt is effectively promoted, the nano silicon dioxide has a larger specific surface area, a stable three-dimensional structure is easy to form, the acting force between asphaltene molecules is weakened, the agglomeration of the asphaltene particles is slowed down, a certain supporting and buffering effect is produced on the asphaltene particles, the agglomerated asphaltene particles in the aged asphalt are promoted to be dispersed in the regenerated asphalt system uniformly again, and the aged asphalt can be recovered into a regenerated network after the aged network is crosslinked and the aged structure is recovered.

As one embodiment of the present application, the regenerative crosslinking agent is an epoxy group-containing compound.

The application adopts the compound containing epoxy groups to repair the aged and broken SBS, the SBS is a styrene-butadiene-styrene segmented copolymer and is of a triblock structure, the SBS molecular chain segments can be broken into two SB molecular chain segments in the aging process, the two SB molecular chain segments respectively have hydroxyl ends and carboxyl ends, the epoxy groups have higher reactivity, oxygen atoms in the epoxy groups can be attacked by nucleophilic reagents to generate ring opening reaction, the ring structure is opened to form an open chain product, the epoxy groups with higher reactivity can react with the hydroxyl ends and the carboxyl ends of the two SB molecular chain segments to crosslink the aged SBS broken blocks, and the three-dimensional network structure is recovered, so that the diblock (SB) is recovered into the triblock (SBS) to achieve the repairing effect on the aged SBS.

As an embodiment of the present application, the chemical structural formula of the regenerated crosslinking agent is:

。

the regenerated cross-linking agent adopted in the application contains epoxy groups and ether bonds, has lipophilicity, can be dissolved and dispersed in asphalt molecules, and reacts with terminal hydroxyl groups and terminal carboxyl groups of SB molecule chain segments to recover broken SBS molecule chain segments.

As an embodiment of the present application, after the old SBS modified asphalt and the matrix asphalt are heated and mixed, an SBS modifier is added, stirred, then a regenerant is added, after shearing and mixing, a regenerated cross-linking agent is added, after stirring, heat preservation and development are performed, and an intermediate product is obtained, which comprises:

As an embodiment of the present application, the warm mix agent comprises the following raw materials in parts by weight: 30-40 parts of cetyl trimethyl ammonium chloride, 20-30 parts of polyethylene wax and 5-10 parts of polyalcohol.

The hexadecyl trimethyl ammonium chloride adopted in the application is a cationic surfactant, the hexadecyl trimethyl ammonium chloride has polar and nonpolar molecules, when the hexadecyl trimethyl ammonium chloride is mixed with water and hot asphalt, the head of the polar molecule is attracted by polar water molecules and is in an inverted state, when the number of molecules at an interface reaches saturation, a spherical micelle of the polar molecule facing the asphalt is formed, the polar molecule of the micelle wraps the water, so that a water film is formed in the asphalt mixture, the water film can effectively lubricate the inside of the mixture, the viscosity of the asphalt is reduced, the warm mixing effect is achieved, the polyalcohol can serve as a solubilizer, the hydrogen bonding effect with the surface of the asphaltene is achieved, asphaltene particles are further dispersed, the miscibility of new and old asphalt is promoted, meanwhile, the stability of the liquid crystal structure of the cationic surfactant is improved, the polyethylene wax can play the thickening and lubricating roles, and the warm mixing effect is further improved.

Specifically, the preparation steps of the warm mix agent comprise: adding cetyl trimethyl ammonium chloride into deionized water, stirring at 35deg.C for 2 hr, adding polyalcohol and polyethylene wax, stirring at 35deg.C for 2 hr, and standing at room temperature for 3 hr.

As one embodiment of the present application, the plasticizing softener includes cracked petroleum byproducts.

The asphalt is doped with the cracked petroleum byproducts, and the cracked petroleum byproducts can be filled in gaps among long-chain molecules of the asphalt, so that the molecular distance is prolonged, the chemical force among macromolecules is correspondingly reduced, and the macromolecular chain is promoted to slide, so that the flexibility and rheological property of an asphalt regeneration system are improved, and the warm mixing effect can be further promoted.

Specifically, cracked petroleum byproducts include heavy distillates, resids, deasphalted bottoms, and the like.

As an embodiment of the present application, the step of adding the old mineral aggregate and the filler powder to the asphalt base material, and heating and stirring to obtain a finished asphalt mixture includes:

The main component in the limestone mineral powder is calcium carbonate, and the old mineral material and the limestone mineral powder are added into the asphalt base material to serve as fillers, so that the utilization rate of the waste SBS mixture can be further improved, the surface atomic activity of the limestone mineral powder is higher, the adsorption effect on asphalt molecules can be increased, and the segregation of the asphalt molecules is avoided.

The above technical solutions of the present application are described in detail below with reference to specific embodiments.

Example 1

The preparation method of the low-carbon recycling modified asphalt mixture comprises the following steps:

crushing the waste SBS mixture, and then performing thermal cracking at the thermal cracking temperature of 250 ℃ for 20min to obtain a thermal cracking product;

mixing the old SBS modified asphalt with matrix asphalt at 140 ℃ for 30min, adding an SBS modifier in batches, continuously stirring, adding a regenerant, shearing and mixing at a shearing rate of 3000rpm for 45min, adding a regenerated cross-linking agent, stirring, and developing at 140 ℃ for 2h to obtain an intermediate product;

wherein, the raw materials of the regenerant comprise: 40g of vegetable asphalt, 35g of epoxidized soybean oil, 20g of diallyl phthalate, 15g of polyphosphate and 10g of nano silicon dioxide; the regenerated cross-linking agent is a compound containing epoxy groups;

adding a cracking petroleum byproduct and a warm mixing agent into the intermediate product, and shearing and mixing to obtain an asphalt base material; wherein, the raw materials of the warm mix agent comprise: 35g of cetyl trimethyl ammonium chloride, 25g of polyethylene wax and 7g of polyalcohol;

and adding the old mineral aggregate and limestone mineral powder into the asphalt base material, and stirring and mixing at 125 ℃ to obtain a finished asphalt mixture.

Example 2

crushing the waste SBS mixture, and then performing thermal cracking at the thermal cracking temperature of 240 ℃ for 25min to obtain a thermal cracking product;

mixing the old SBS modified asphalt with matrix asphalt at 130 ℃ for 35min, adding an SBS modifier in batches, continuously stirring, adding a regenerant, shearing and mixing for 50min at a shearing rate of 2500rpm, adding a regenerated cross-linking agent, stirring, and developing for 2.5h at 130 ℃ to obtain an intermediate product;

wherein, the raw materials of the regenerant comprise: 30g of vegetable asphalt, 25g of epoxidized soybean oil, 15g of diallyl phthalate, 10g of polyphosphate and 5g of nano silicon dioxide; the regenerated cross-linking agent is a compound containing epoxy groups;

adding a cracking petroleum byproduct and a warm mixing agent into the intermediate product, and shearing and mixing to obtain an asphalt base material; wherein, the raw materials of the warm mix agent comprise: 30g of cetyl trimethyl ammonium chloride, 20g of polyethylene wax and 5g of polyalcohol;

and adding the old mineral aggregate and limestone mineral powder into the asphalt base material, and stirring and mixing at 120 ℃ to obtain a finished asphalt mixture.

Example 3

crushing the waste SBS mixture, and then performing thermal cracking at a thermal cracking temperature of 260 ℃ for 15min to obtain a thermal cracking product;

mixing the old SBS modified asphalt with matrix asphalt at 150 ℃ for 25min, adding an SBS modifier in batches, continuously stirring, adding a regenerant, shearing and mixing at 3500rpm for 40min, adding a regenerated cross-linking agent, stirring, and developing at 150 ℃ for 1.5h to obtain an intermediate product;

wherein, the raw materials of the regenerant comprise: 50g of vegetable asphalt, 45g of epoxidized soybean oil, 30g of diallyl phthalate, 20g of polyphosphate and 15g of nano silicon dioxide; the regenerated cross-linking agent is a compound containing epoxy groups;

adding a cracking petroleum byproduct and a warm mixing agent into the intermediate product, and shearing and mixing to obtain an asphalt base material; wherein, the raw materials of the warm mix agent comprise: 40g of cetyl trimethyl ammonium chloride, 30g of polyethylene wax and 10g of polyalcohol;

and adding the old mineral aggregate and limestone mineral powder into the asphalt base material, and stirring and mixing at 130 ℃ to obtain a finished asphalt mixture.

Comparative example 1

In comparison with example 1, no SBS modifier was added and the rest of the procedure was the same.

Comparative example 2

In comparison with example 1, no regenerated crosslinking agent was added, and the rest of the procedure was the same.

Comparative example 3

In comparison with example 1, no regenerant was added and the rest of the procedure was the same.

Test examples

1. The asphalt mixtures prepared in examples and comparative examples herein were tested for performance.

Penetration, 10 ℃ ductility and toughness S of the asphalt binders prepared in examples 1-3 and comparative examples 1-3 of the present application _BC Tests were conducted and a control group 1 (waste SBS mixture) and a control group 2 (as-received SBS modified asphalt) were set, and the test results are shown in Table 1 below.

TABLE 1

As can be seen from Table 1, the asphalt binders prepared in examples and comparative examples herein have penetration, 10℃ductility and toughness S as compared to the waste SBS mixture _BC The penetration and 10 ℃ ductility of the asphalt base material prepared by the embodiment of the application are the same as those of the original SBS modified asphalt, and only the toughness is different from the original SBS modified asphalt to a certain extent, which shows that the preparation method of the application can effectively improve the consistency and ductility of the aged asphalt.

2. High temperature stability

Dynamic stability evaluation by rutting test (wheel pressure is 0.7MPa, test temperature is 60 ℃) the high temperature stability of the low carbon recycling modified asphalt mixture prepared in the examples and comparative examples requires that the dynamic stability DS of the mixture is more than or equal to 600. The test results are shown in FIG. 1.

As can be seen from fig. 1, the dynamic stability of each group of rutting samples is greater than 600 times/mm, and the requirements for the dynamic stability of the mixture are met. The dynamic stability of the low-carbon recycling modified asphalt mixture prepared in the embodiment of the application is obviously higher than that of the comparative example, which shows that the low-carbon recycling modified asphalt mixture prepared in the embodiment has better high-temperature stability, the comparative example 1 has a certain influence on the regeneration of aged asphalt due to the fact that the SBS modifier is not added, the high-temperature stability of the asphalt mixture prepared in the comparative example 1 is reduced, the comparative example 2 has a certain influence on the high-temperature stability of the regenerated asphalt mixture due to the fact that the SBS modifier is not added, and the comparative example 3 does not add a regenerant, and only regenerates the aged asphalt by means of new asphalt and the SBS modifier, so that the high-temperature stability of the regenerated asphalt mixture is poor.

3. Low temperature crack resistance

The low-temperature performance of the low-carbon recycling modified asphalt mixture prepared in the examples and the comparative examples was experimentally evaluated by adopting a bending creep test, firstly, a rutting plate test piece with a certain size was formed indoors, then, a prism with a size of 250mm×30mm×35mm was cut by a cutting machine, and the test was performed by using a SYD-0728-1 type creep tester, the test loading rate was 50mm/min, the test temperature was 0 ℃, and the test results are shown in Table 2.

TABLE 2

As can be seen from table 2, the creep rate of the low-carbon recycling modified asphalt mixture prepared in the embodiment of the present application is significantly higher than that of the comparative example, which indicates that the low-carbon recycling modified asphalt mixture prepared in the embodiment has better low-temperature crack resistance, and in the comparative example 1, the low-temperature crack resistance of the asphalt mixture prepared in the comparative example 1 is reduced due to the fact that the SBS modifier is not added, the SBS modifier cannot be repaired due to the fact that the regenerated cross-linking agent is not added, the low-temperature crack resistance of the regenerated asphalt mixture is affected due to the fact that the regenerated asphalt mixture is not added, and the aged asphalt is regenerated only by means of the new asphalt and the SBS modifier, so that the low-temperature crack resistance of the regenerated asphalt mixture is poor.

4. Fatigue performance

Four-point bending fatigue tests are carried out on the low-carbon recycling modified asphalt mixtures prepared in the examples and the comparative examples by adopting a UTM tester, and fatigue properties of the low-carbon recycling modified asphalt mixtures are evaluated according to fatigue life. The test piece size was 380mm×50mm×63.5mm, strain level was 400. Mu.. Epsilon., test temperature was 15℃and loading frequency was 5Hz, and the test results are shown in Table 3.

TABLE 3 Table 3

As can be seen from table 3, the fatigue life of the low-carbon recycling modified asphalt mixture prepared in the embodiment of the present application is significantly longer than that of the comparative example, which indicates that the low-carbon recycling modified asphalt mixture prepared in the embodiment has better fatigue performance, and in comparative example 1, the regeneration effect of the aged asphalt is the worst because the SBS modifier is not added, resulting in lower fatigue life of the asphalt mixture prepared in comparative example 1, and in comparative example 2, the regeneration crosslinking agent is not added, the SBS modifier cannot be repaired, the fatigue performance of the regenerated asphalt mixture is the certain influence, and in comparative example 3, the regeneration effect of the aged asphalt is the worst because the regenerant is not added, and the fatigue life is the lowest.

The foregoing description is only of the optional embodiments of the present application, and is not intended to limit the scope of the patent application, and all equivalent structural changes made by the specification and drawings of the present application or direct/indirect application in other related technical fields are included in the scope of the patent protection of the present application.

Claims

1. The preparation method of the low-carbon recycling modified asphalt mixture is characterized by comprising the following steps of:

2. The method for preparing a modified asphalt mixture for recycling low carbon according to claim 1, wherein in the step of performing thermal cracking, the thermal cracking temperature is 240 ℃ to 260 ℃ and the thermal cracking time is 15min to 25min.

3. The method for preparing the modified asphalt mixture for low carbon recycling according to claim 1, wherein the raw materials of the regenerant comprise, in parts by weight: 30-50 parts of plant asphalt, 25-45 parts of epoxidized soybean oil, 15-30 parts of diallyl phthalate, 10-20 parts of polyphosphate and 5-15 parts of nano silicon dioxide.

4. The method for preparing a modified asphalt mixture for low carbon recycling according to claim 1, wherein the regenerated cross-linking agent is a compound containing an epoxy group.

5. The method for preparing a modified asphalt mixture for low carbon recycling according to claim 4, wherein the regenerated cross-linking agent has a chemical structural formula:

。

6. the method for preparing the modified asphalt mixture for recycling low carbon according to claim 1, wherein the steps of heating and mixing the old SBS modified asphalt with the matrix asphalt, adding the SBS modifier, stirring, adding the regenerant, shearing and mixing, adding the regenerated cross-linking agent, stirring, and performing heat preservation development to obtain an intermediate product comprise the following steps:

7. The method for preparing the modified asphalt mixture with low carbon recycling according to claim 1, wherein the raw materials of the warm mix agent comprise, by weight: 30-40 parts of cetyl trimethyl ammonium chloride, 20-30 parts of polyethylene wax and 5-10 parts of polyalcohol.

8. The method for preparing a modified asphalt mixture for low carbon recycling according to claim 1, wherein the plasticizing softener comprises cracked petroleum byproduct.

9. The method for preparing the modified asphalt mixture with low carbon recycling according to claim 1, wherein the step of adding the old mineral aggregate and the filling powder into the asphalt base material, heating and stirring the mixture to obtain the finished asphalt mixture comprises the following steps: