Waste asphalt / SBS composite modified asphalt, preparation method and application thereof

Abstract

The application discloses a kind of waste cement / SBS composite modified asphalt and preparation method thereof.Waste cement / SBS composite modified asphalt of the application includes the following components by weight parts: base asphalt: 100 parts, compatibilizer: 0.5-5 parts, composite SBS modifier: 1-3 parts, stabilizer: 0.1-0.4 parts, modified waste cement: 12-30 parts.The waste cement / SBS composite modified asphalt of the application meets the index requirements of I-D grade modified asphalt, and has the characteristics of heat storage stability, low SBS content, excellent temperature sensitivity, etc., reduces the production cost of modified asphalt, and realizes the resource utilization of waste tire rubber powder.

Description

Technical Field

[0001] This invention relates to the field of road asphalt, specifically to a waste mortar / SBS composite modified asphalt, its preparation method, and its application. Background Technology

[0002] Modified asphalt refers to asphalt binder prepared by adding high molecular polymers such as rubber and resin, or other modifiers, to base asphalt, or by production processes such as air blowing oxidation. Modifiers are various organic or inorganic materials incorporated into asphalt; they are soluble in the asphalt and improve its performance by coating aggregates or reacting with it. China's modified asphalt production and application technology has made significant progress over the past two decades and is now widely used in high-grade highway construction, with an annual consumption of approximately 6 million tons, of which SBS modified asphalt accounts for over 80%.

[0003] Currently, well-known modified asphalt brands include Novopalt, Shell, Esso, Koch, and Caltex, who have successively launched mature modified asphalt processing technologies and products. In the US modified asphalt market, SBS modified asphalt accounts for over 70%, and in the European modified asphalt market, it accounts for over 50%. The Chinese modified asphalt market initially focused on SBR modified asphalt, followed by PE modified asphalt for a long period. Later, with the increasing maturity of SBS production technology at companies like Yanshan Petrochemical and Yueyang Petrochemical, SBS modified asphalt officially became the mainstream modified asphalt product in my country. However, these widely used SBS modified asphalt roads still face some problems: for example, their road performance has not been further improved over the years, and many of their characteristics are showing signs of fatigue under the heavy traffic and humid climate conditions of southern provinces; the modification methods are limited, leading to early-stage defects, easy aging, rapid performance degradation, and inability to meet the requirements of special road sections. Furthermore, the cost of SBS modified asphalt remains high, making cost reduction and quality improvement a challenge for the industry.

[0004] In recent years, the concept of sustainable development has gained increasing popularity, accelerating the application and research of a large amount of waste materials in the road transportation sector. As a typical solid waste polymer material, the road resource utilization of waste tires (≥15 million tons / year) is a crucial choice for current road construction and maintenance, as well as the value-added circular development of the polymer industry. Rubber asphalt technology, which involves grinding crushed tires into rubber powder for asphalt modification and road construction, can not only replace petroleum resources and reduce costs, but also effectively utilize waste tires. It is one of the representative ways to achieve high-value applications of waste rubber and plastic materials. If waste rubber and plastic materials can partially replace SBS modifiers, the production cost of modified asphalt will undoubtedly be reduced. However, waste tire rubber powder is mostly vulcanized rubber powder, with cross-linked rubber molecular chains, making it difficult to effectively disperse in asphalt. It mainly exists as macroscopic swollen particles, exhibiting the characteristics of a solid-liquid two-phase system. The presence of a large number of swollen rubber particles leads to serious problems such as high production energy consumption, high processing viscosity, poor storage stability, heavy construction fume pollution, and difficulty in road compaction.

[0005] The inherent poor compatibility and high processing viscosity between rubber powder and asphalt significantly limit the increase in rubber powder content. Tire rubber has a multi-layered cross-linked network structure, which restricts the movement of rubber molecular chains. This results in the diffusion of small asphalt molecules into the cross-linked network within the rubber-asphalt system, i.e., limited swelling rather than dissolution. At this point, the cross-linked network is not significantly damaged, and the rubber powder exists as swollen rubber particles, leading to a substantial increase in viscosity and a rapid decline in processing performance. Therefore, it is necessary to partially open the cross-linked network structure to address the compatibility and dispersibility issues.

[0006] CN114058097A discloses a high-performance decrosslinked rubber asphalt and its preparation method. This patent proposes a novel method for decrosslinking rubber powder, including preliminary and deep decrosslinking treatment using a single-screw extruder and internal mixer, and the addition of polyolefin modifiers and SBS modifiers as separating agents to deeply degrade the rubber, thereby improving the cohesiveness of the rubber asphalt, reducing its Brinell viscosity, improving its workability, and achieving a higher rubber content. However, this method uses a traditional mechanical-thermal degradation method, which has high energy consumption, poor uniformity, and releases a significant amount of harmful fumes during degradation.

[0007] CN114685846B discloses a supercritical decrosslinking pretreated rubber powder, rubber powder-modified asphalt, and their preparation method. This patent involves uniformly mixing rubber powder, a decrosslinking agent, and dry ice, then placing the mixture in a sealed high-pressure reactor. Electric heating is applied to raise the temperature and pressure of carbon dioxide within the reactor, reaching a supercritical state. A magnetically sealed stirring paddle is used in this supercritical carbon dioxide environment to ensure a thorough and uniform reaction between the rubber powder and the decrosslinking agent, yielding supercritical decrosslinking pretreated rubber powder. This supercritical decrosslinking pretreated rubber powder is then incorporated into preheated, fluidized base asphalt, allowing for thorough mixing under high-speed mechanical stirring to obtain supercritical decrosslinking pretreated rubber powder-modified asphalt. This method requires stringent preparation conditions, is difficult to promote, and produces modified asphalt with high viscosity, making it unsuitable for practical road construction needs.

[0008] In summary, developing a waste rubber mortar / SBS composite modified asphalt, realizing the transformation of waste tire rubber powder from devalued recycling to value-added recycling and reducing the production cost of pure SBS modified asphalt, has significant social and economic implications. Summary of the Invention

[0009] To address the shortcomings of existing technologies, this invention provides a waste rubber mortar / SBS composite modified asphalt and its preparation method. The waste rubber mortar / SBS composite modified asphalt of this invention meets the requirements for ID-grade modified asphalt and exhibits characteristics such as thermal storage stability, low SBS content, and excellent temperature sensitivity. This reduces the production cost of modified asphalt and realizes the resource utilization of waste tire rubber powder.

[0010] The first aspect of this invention provides a waste mortar / SBS composite modified asphalt, comprising the following components by weight:

[0011] Base bitumen: 100 parts;

[0012] Compatibilizer: 0.5 to 5 parts, preferably 0.5 to 2 parts;

[0013] Composite SBS modifier: 1-3 parts, preferably 1-2.5 parts;

[0014] Stabilizer: 0.1 to 0.4 parts, preferably 0.1 to 0.3 parts;

[0015] Modified waste mortar: 12-30 parts, preferably 20-30 parts.

[0016] Furthermore, the properties of the base asphalt include: a penetration of 68–74 mm at 25°C, a softening point of 47–49°C, a dynamic viscosity of 195 Pa·s–220 Pa·s at 60°C, and a residual ductility of 7–10 cm at 10°C. By mass fraction, the saturated components account for 12.8%–15.1%, the aromatic components for 48.7%–52.3%, the resins for 23.2%–27.6%, and the asphaltenes for 7.1%–12.5%.

[0017] Furthermore, the base bitumen is preferably obtained by atmospheric and vacuum distillation of one or more of the following: crude oil from sand, Kuwait crude oil, and Basra crude oil.

[0018] Furthermore, the properties of the compatibilizer include: a kinematic viscosity of 50 mmHg at 100°C. 2 / s~65mm 2 / s, flash point is 206℃~220℃, by mass fraction, saturated fraction accounts for 30%~42%, aromatic fraction accounts for 48%~57%, resin accounts for 8%~13%, asphaltene content is less than 2%; weight average molecular weight is 1990~2140, molecular weight distribution width is 1.6~3.7.

[0019] Furthermore, the composite SBS modifier is an SBS modifier that has undergone pre-degradation extrusion treatment.

[0020] Furthermore, the composite SBS modifier includes linear SBS modifiers and star-shaped SBS modifiers. The linear SBS modifier accounts for 60% to 85% of the total mass of the composite SBS modifier.

[0021] Furthermore, the pre-degradation extrusion treatment method includes: putting linear SBS modifier and star-shaped SBS modifier into a grinding mill, shearing and grinding, and extruding and granulating to obtain composite SBS modifier.

[0022] Furthermore, the linear SBS modifier has the following properties: a styrene to butadiene mass ratio of 1:(4-7.3) and a tensile strength of 280-350 kg / cm². 2 It has an elongation at break of 800%–910% and a Shore hardness of 75±6HA.

[0023] Furthermore, the star-shaped SBS modifier has the following properties: a styrene to butadiene mass ratio of 1:(1.2-1.8) and a tensile strength of 200-300 kg / cm². 2 Its elongation at break is 720%–800%, and its Shore hardness is 90±5HA.

[0024] Furthermore, the stabilizer includes a first stabilizer and a second stabilizer, wherein the first stabilizer is elemental sulfur, and the second stabilizer is at least one of tetramethylthiuram disulfide, morpholino disulfide, ferric chloride, ferric oxide, ferrous chloride, copper chloride, nano zinc oxide, montmorillonite, and octadecyl alcohol ester of 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate.

[0025] Furthermore, the modified waste mortar includes waste rubber powder and composite filler oil.

[0026] Further, the waste rubber powder comprises, by mass fraction, 5.9 wt% to 7.6 wt% acetone-soluble portion, 46.1 wt% to 48.4 wt% natural rubber, 9.4 wt% to 10.3 wt% synthetic rubber, 26.1 wt% to 27.3 wt% carbon black, and 6.2 wt% to 8.4 wt% other fillers. The waste rubber powder is preferably obtained by crushing at least a portion of the tread, sidewall, and bead of a truck, and more preferably by crushing the tread portion of a truck.

[0027] Furthermore, the particle size of the waste adhesive powder is 20 mesh to 60 mesh, preferably 40 mesh to 60 mesh.

[0028] Furthermore, the composite filler oil is an aromatic oil and atmospheric residue.

[0029] Furthermore, the properties of the aromatic-rich oil include: 27wt%–30wt% saturated components, 52wt%–60wt% aromatic components, 13wt%–19wt% resins, and 0wt%–0.2wt% asphaltenes. The four-component analysis method is T0618-1993 Asphalt Chemical Component Test (Four-component Method); H ar 15wt%–17wt%, H α 25wt%–28wt%, H β accounting for 43wt%~46t%, H γ It accounts for 14wt% to 16wt%, with a C / H molar ratio of 0.82 to 0.88, an aromatic carbon fraction of 48wt% to 51wt%, a cycloalkanes carbon fraction of 15wt% to 18wt%, and an alkyl carbon fraction of 35wt% to 37wt%.

[0030] Furthermore, the properties of the slag include: a flash point of 246–258°C, a sulfur content of 2.77 wt%–3.63 wt%, and by mass fraction, saturated components of 26.1%–37.7%, aromatic components of 20.2%–34.5%, resins of 18.3%–24.8%, and asphaltenes of 21.3%–30.1%, with asphaltenes preferably being 21.3%–25.0%.

[0031] Furthermore, the slag also has the following basic properties: residual carbon value of 19wt% to 28wt%, total nickel and vanadium content of 310 to 365 μg / g, and condensation index CI of 0.22 to 0.30.

[0032] Furthermore, the atmospheric residue can be Tarim Basin atmospheric residue or other atmospheric residues that meet the above properties. The atmospheric residue is a fraction with an initial boiling point greater than 350°C.

[0033] A second aspect of the present invention provides a method for preparing the above-mentioned waste mortar / SBS composite modified asphalt, comprising:

[0034] (1) Preparation of composite SBS modifier;

[0035] (2) Preparation of modified waste mortar;

[0036] (3) Heat the base asphalt to a molten state, add composite SBS modifier, compatibilizer and modified waste mortar, shear, and stir to develop after shearing;

[0037] (4) Add a stabilizer to the material obtained in step (3), continue stirring and developing, and finally obtain waste mortar / SBS composite modified asphalt.

[0038] Furthermore, in step (1), the preparation process of the composite SBS modifier is as follows:

[0039] Linear SBS modifier and star-shaped SBS modifier are fed into a grinding mill, sheared and ground, and then extruded and granulated to obtain a composite SBS modifier.

[0040] Furthermore, in the preparation process of the composite SBS modifier, the shearing and grinding temperature is 120℃~150℃, preferably 125℃~146℃; the shearing and grinding time is 20~40min. The extrusion granulation preferably uses a twin-screw extruder. The number of extrusions is 1~5 times, preferably 3 times, wherein the first extrusion temperature is 120℃~130℃, and the screw speed is 180~300r / min; the second extrusion temperature is between 130℃~140℃, and the screw speed is between 320~450r / min; the third extrusion temperature is between 145℃~160℃, and the screw speed is between 500~650r / min, wherein the temperature of each subsequent extrusion is higher than the temperature of the previous extrusion.

[0041] Further, in step (2), the method for preparing the modified waste mortar includes:

[0042] a: Mix waste rubber powder with aromatic oil and ordinary slag evenly, and introduce oxygen-containing gas during the stirring process to react and obtain a pretreated mixture;

[0043] b: Mix the pretreated mixture obtained in step a with the catalyst and perform vacuum distillation;

[0044] c: The residue at the bottom of the reactor obtained in step b is subjected to high-speed shearing to obtain modified waste sludge.

[0045] Further, in step a, the mass ratio of the waste rubber powder, aromatic oil, and ordinary slag is 1:(3-5):(5-8).

[0046] Further, in step a, the oxygen-containing gas is preferably air, and the air flow rate is 0.02–0.11 m³ / s. 3 / (kg·h), reaction time is 20–40 min, reaction temperature is 120–150 °C, and stirring speed is 700–900 r / min.

[0047] Further, in step b, the catalyst is one or more of 3,6-dioxa-1,8-octanedithiol, dithiothreitol, hexadecylamine, and 2,2-dibenzoylaminodiphenyldisulfide and diphenyl disulfide.

[0048] Further, in step b, the mass ratio of the waste adhesive powder to the catalyst is 100:(3-8).

[0049] Further, in step b, the vacuum distillation is carried out in a vacuum distillation vessel. The conditions for vacuum distillation are: vacuum distillation until the mass ratio of the residue at the bottom of the vessel to the initially added gum powder is 1:(0.2~0.5), and the rotor speed inside the vacuum distillation vessel during the vacuum distillation process is 100~300 r / min.

[0050] Further, in step c, the shearing rate is 6000-8000 r / min, the shearing time is 40-80 min, and the shearing temperature is 130-150℃.

[0051] Further, in step (3), the heating temperature of the base asphalt is 140–155°C. Both shearing and stirring development are carried out under a protective gas, preferably an inert gas and / or N2. The shearing rate is 4000–6000 r / min, preferably 4000–5500 r / min, the shearing time is 60–80 min, and the required temperature during shearing is 170–185°C. The stirring speed is 600–800 r / min, the development time is 20–40 min, and the development temperature is 160°C–195°C, preferably 170°C–180°C.

[0052] Further, in step (4), the stabilizer is preferably added in several portions, with an interval of 20 to 40 minutes between each addition; more preferably, it is added in two separate additions. The stirring speed is 600 to 800 r / min, the development time is 3 to 4 hours, and the development temperature is 170°C to 195°C, preferably 175°C to 185°C.

[0053] A third aspect of the present invention provides an application of the above-mentioned waste mortar / SBS composite modified asphalt in road asphalt.

[0054] Compared with the prior art, the present invention has the following advantages:

[0055] (1) The matrix asphalt of this invention is synergistically combined with the composite SBS modifier, modified waste mortar and stabilizer components, which can greatly improve the storage stability of modified asphalt, reduce the viscosity of modified asphalt at 135℃, meet the index requirements of ID grade modified asphalt, and the composite modified asphalt has better temperature sensing performance. In the preparation process, the modified waste mortar partially replaces the SBS modifier, which reduces the production cost of modified asphalt.

[0056] (2) The modified waste rubber mud of this invention preferably uses waste rubber powder with high natural rubber content and low synthetic rubber content, which is easier to degrade, has low carbon black content, and better compatibility with asphalt. The rubber powder is modified using a two-stage decrosslinking technology. The first stage, low-temperature oxidative decrosslinking treatment, selectively breaks sulfur bonds without damaging the CC backbone, thus initially reducing the crosslinking density of the rubber powder. The second stage, high-temperature vacuum catalytic decrosslinking treatment, is carried out in a homogeneous environment, which avoids damage to the CC backbone during the efficient decrosslinking process. This not only reduces the difficulty of fusion between the rubber powder and asphalt, but also preserves the polymer properties of rubber and improves the overall performance of the modified asphalt.

[0057] (3) In the preparation process of the modified waste sludge of this invention, the modification of the rubber powder is carried out in a mixture of aromatic oil and atmospheric residue with a special composition. During the vacuum distillation process, the mixed oil composed of aromatic oil and atmospheric residue can more easily diffuse into the network structure of the rubber powder, thereby swelling the rubber powder and increasing the contact area for the de-crosslinking reaction. The metal elements contained in the mixed oil, together with the added catalyst, play a dual catalytic role, reducing the difficulty of de-crosslinking. The final modified waste sludge is fully de-crosslinked and swollen, eliminating the long-term high-temperature swelling and boiling process in the preparation of modified asphalt, thus improving production efficiency. During the preparation of modified waste sludge, the toxic and harmful fumes generated by the de-crosslinking reaction are dissolved in the mixed oil and collected in a centralized manner, avoiding environmental problems caused by fugitive emissions. Detailed Implementation

[0058] The technical solution of the present invention is further described below through embodiments, but these embodiments cannot limit the scope of protection of the present invention, and the wt% involved refers to the mass fraction.

[0059] Unless otherwise specified, the experimental methods used in the following examples are conventional methods in the art. Unless otherwise specified, the experimental materials used in the following examples were purchased from conventional biochemical reagent stores.

[0060] Example 1

[0061] (1) Linear SBS modifier and star-shaped SBS modifier (linear SBS modifier accounts for 80 wt% of the total amount, and the linear SBS modifier has the following properties: the mass ratio of styrene to butadiene is 20:80, and the tensile strength is 300 kg / cm²) 2 The elongation at break is 820%, and the Shore hardness is 75HA. The star-shaped SBS modifier has the following properties: the mass ratio of styrene to butadiene is 40:60, and the tensile strength is 250 kg / cm². 2 A modifier with an elongation at break of 750% and a Shore hardness of 90HA was fed into a grinding mill and sheared and ground at 130℃ for 40 minutes until the two were evenly mixed. The evenly mixed modifier was then extruded and granulated three times. The first extrusion temperature was 125℃ and the screw speed was 200 r / min. The second extrusion temperature was 135℃ and the screw speed was 350 r / min. The third extrusion temperature was 155℃ and the screw speed was 500 r / min, thus obtaining a composite SBS modifier.

[0062] (2) Preparation of modified waste rubber sludge: a: 100 parts of 60-mesh truck tire tread waste rubber powder (acetone-soluble portion 7.34 wt%, natural rubber 47.75 wt%, synthetic rubber 10.06 wt%, carbon black 26.93 wt%, and other fillers 7.92 wt%) were mixed evenly with 300 parts of aromatic oil (properties shown in Table 1) and 500 parts of Tarim River slag (properties shown in Table 2). Air was introduced during the stirring process, and the air flow rate was 0.06 m³ / min. 3 The reaction was carried out at a reaction rate of 145℃ for 30 minutes and a stirring speed of 800 r / min to obtain a pretreated mixture. b: The pretreated mixture obtained in a was mixed with 2 parts diphenyl disulfide and 2 parts dithiothreitol, and then placed in a vacuum distillation vessel for vacuum distillation. The rotor speed inside the vessel was adjusted to 300 r / min, and the mass of the distillate was measured. Vacuum distillation was stopped when the distillate reached 600 parts (300 parts of residue at the bottom of the vessel). c: The residue at the bottom of the vessel obtained in b was subjected to high-speed shearing at a rate of 7500 r / min for 50 minutes at a temperature of 140℃. Modified waste sludge was obtained after shearing.

[0063] (3) 100 parts of base bitumen (prepared from pure crude oil in sand, with a penetration of 710.1 mm at 25℃, a softening point of 48.1℃, a dynamic viscosity of 214 Pa·s at 60℃, and a residual ductility (10℃) of 8 cm, and by mass fraction, saturated components account for 14.9%, aromatic components account for 52.1%, resins account for 24.6%, and asphaltenes account for 8.4%) were heated to a fluid state at 140℃, and 0.6 parts of compatibilizer (resin obtained from solvent deasphalting process, with a kinematic viscosity of 60 mm at 100℃) were added. 2 / s, flash point is 212℃, by mass fraction, saturated fraction accounts for 33%, aromatic fraction accounts for 56.5%, resin accounts for 10%, asphaltene accounts for 0.5%; weight average molecular weight is 2090, molecular weight distribution width is 2.7. ), 1.8 parts of the composite SBS modifier prepared in step (1) and 25 parts of the modified waste sludge prepared in step (2) were subjected to high-speed shearing at 175℃ in N2 atmosphere for 60 min, with a shearing rate of 4000 r / min. After shearing, the mixture was stirred and developed at 175℃ for 30 min, with a stirring speed of 600 r / min.

[0064] (4) Slowly add 0.08 parts of stabilizer (elemental sulfur, nano zinc oxide, tetramethylthiuram disulfide, wherein, by the total mass of the stabilizer, the content of elemental sulfur is 60%, the content of nano zinc oxide is 10%, and the content of tetramethylthiuram disulfide is 30%) to the material in step (3). After 30 minutes, add another 0.08 parts of the same stabilizer. Each addition should be completed within 5 minutes. After the addition is completed, continue stirring and developing for 3 hours at a development temperature of 180℃ and a stirring speed of 800 r / min. Once development is complete, waste mortar / SBS composite modified asphalt A1 is obtained.

[0065] Example 2

[0066] (1) Linear SBS modifier and star-shaped SBS modifier (linear SBS modifier accounts for 85 wt% of the total amount, and the linear SBS modifier has the following properties: the mass ratio of styrene to butadiene is 20:80, and the tensile strength is 300 kg / cm) 2 The elongation at break is 820%, and the Shore hardness is 75HA. The star-shaped SBS modifier has the following properties: the mass ratio of styrene to butadiene is 40:60, and the tensile strength is 250 kg / cm². 2A modifier with an elongation at break of 750% and a Shore hardness of 90HA was fed into a grinding mill and sheared and ground at 130℃ for 40 minutes until the two were evenly mixed. The evenly mixed modifier was then extruded and granulated three times. The first extrusion temperature was 125℃ and the screw speed was 200 r / min. The second extrusion temperature was 135℃ and the screw speed was 350 r / min. The third extrusion temperature was 155℃ and the screw speed was 500 r / min, thus obtaining a composite SBS modifier.

[0067] (2) Preparation of modified waste rubber sludge: a: Mix 100 parts of 60-mesh truck tire tread waste rubber powder (same as in Example 1) with 300 parts of aromatic oil (properties shown in Table 1) and 550 parts of Tarim River slag (properties shown in Table 2) evenly. During the stirring process, air is introduced for reaction, and the air flow rate is 0.06 m³ / min. 3 The reaction was carried out at a reaction rate of 145℃ and a stirring speed of 800 r / min for 30 min, resulting in a pretreated mixture. b: The pretreated mixture obtained in a was mixed with 2 parts diphenyl disulfide and 1 part dithiothreitol, and then placed in a vacuum distillation vessel for vacuum distillation. The rotor speed inside the vessel was adjusted to 300 r / min, and the mass of the distillate was measured. Vacuum distillation was stopped when the distillate reached 650 parts (300 parts of residue at the bottom of the vessel). c: The residue at the bottom of the vessel obtained in b was subjected to high-speed shearing at a rate of 7500 r / min for 50 min at a temperature of 140℃. Modified waste sludge was obtained after the shearing was completed.

[0068] (3) 100 parts of base bitumen (prepared from pure crude oil in sand, with a penetration of 710.1 mm at 25℃, a softening point of 48.1℃, a dynamic viscosity of 214 Pa·s at 60℃, and a residual ductility (10℃) of 8 cm, and by mass fraction, saturated components account for 14.9%, aromatic components account for 52.1%, resins account for 24.6%, and asphaltenes account for 8.4%) were heated to a fluid state at 140℃, and 0.6 parts of compatibilizer (resin obtained from solvent deasphalting process, with a kinematic viscosity of 60 mm at 100℃) were added. 2 / s, flash point is 212℃, by mass fraction, saturated fraction accounts for 33%, aromatic fraction accounts for 56.5%, resin accounts for 10%, asphaltene accounts for 0.5%; weight average molecular weight is 2090, molecular weight distribution width is 2.7. ), 1.8 parts of the composite SBS modifier prepared in step (1) and 25 parts of the modified waste sludge prepared in step (2) were subjected to high-speed shearing at 175℃ in N2 atmosphere for 60 min, with a shearing rate of 4000 r / min. After shearing, the mixture was stirred and developed at 175℃ for 30 min, with a stirring speed of 600 r / min.

[0069] (4) Slowly add 0.09 parts of stabilizer (elemental sulfur, nano zinc oxide, tetramethylthiuram disulfide, wherein, by the total mass of the stabilizer, the content of elemental sulfur is 70%, the content of nano zinc oxide is 5%, and the content of tetramethylthiuram disulfide is 25%) to the material in step (3). After 30 minutes, add another 0.08 parts of the same stabilizer. Each addition should be completed within 5 minutes. After the addition is completed, continue stirring and developing for 3.5 hours at a development temperature of 183℃ and a stirring speed of 800 r / min. Once development is complete, waste mortar / SBS composite modified asphalt A2 is obtained.

[0070] Example 3

[0071] (1) Linear SBS modifier and star-shaped SBS modifier (linear SBS modifier accounts for 80 wt% of the total amount, and the linear SBS modifier has the following properties: the mass ratio of styrene to butadiene is 20:80, and the tensile strength is 300 kg / cm²) 2 The elongation at break is 820%, and the Shore hardness is 75HA. The star-shaped SBS modifier has the following properties: the mass ratio of styrene to butadiene is 40:60, and the tensile strength is 250 kg / cm². 2 A modifier with an elongation at break of 750% and a Shore hardness of 90HA was fed into a grinding mill and sheared and ground at 135℃ for 35 minutes until the two were evenly mixed. The evenly mixed modifier was then extruded and granulated three times. The first extrusion temperature was 125℃ and the screw speed was 200r / min. The second extrusion temperature was 135℃ and the screw speed was 350r / min. The third extrusion temperature was 150℃ and the screw speed was 500r / min, thus obtaining a composite SBS modifier.

[0072] (2) Preparation of modified waste rubber sludge: a: Mix 100 parts of 60-mesh truck tire tread waste rubber powder (same as in Example 1) with 300 parts of aromatic oil (properties shown in Table 1) and 500 parts of Tarim River slag (properties shown in Table 2) evenly. During the stirring process, air is introduced for reaction, and the air flow rate is 0.06 m³ / min. 3 The reaction was carried out at a reaction rate of 145℃ for 30 minutes and a stirring speed of 800 r / min to obtain a pretreated mixture. b: The pretreated mixture obtained in a was mixed with 2 parts diphenyl disulfide and 2 parts dithiothreitol, and then placed in a vacuum distillation vessel for vacuum distillation. The rotor speed inside the vessel was adjusted to 300 r / min, and the mass of the distillate was measured. Vacuum distillation was stopped when the distillate reached 600 parts (300 parts of residue at the bottom of the vessel). c: The residue at the bottom of the vessel obtained in b was subjected to high-speed shearing at a rate of 8000 r / min for 50 minutes at a temperature of 135℃. Modified waste sludge was obtained after shearing.

[0073] (3) 100 parts of base bitumen (prepared from pure crude oil in sand, with a penetration of 710.1 mm at 25℃, a softening point of 48.1℃, a dynamic viscosity of 214 Pa·s at 60℃, and a residual ductility (10℃) of 8 cm, and by mass fraction, saturated components account for 14.9%, aromatic components account for 52.1%, resins account for 24.6%, and asphaltenes account for 8.4%) were heated to a fluid state at 140℃, and 0.6 parts of compatibilizer (resin obtained from solvent deasphalting process, with a kinematic viscosity of 60 mm at 100℃) were added. 2 / s, flash point is 212℃, by mass fraction, saturated fraction accounts for 33%, aromatic fraction accounts for 56.5%, resin accounts for 10%, asphaltene accounts for 0.5%; weight average molecular weight is 2090, molecular weight distribution width is 2.7. ), 2 parts of the composite SBS modifier prepared in step (1) and 23 parts of the modified waste sludge prepared in step (2) were subjected to high-speed shearing at 175℃ in a N2 atmosphere for 60 min, with a shearing rate of 4000 r / min. After shearing, the mixture was stirred at 175℃ for 30 min at a stirring speed of 600 r / min.

[0074] (4) Slowly add 0.1 parts of stabilizer (elemental sulfur, nano zinc oxide, tetramethylthiuram disulfide, wherein, by the total mass of the stabilizer, the content of elemental sulfur is 60%, the content of nano zinc oxide is 10%, and the content of tetramethylthiuram disulfide is 30%) to the material in step (3). After 30 minutes, add another 0.1 parts of the same stabilizer. Each addition should be completed within 5 minutes. After the addition is completed, continue stirring and developing for 3 hours. The development temperature is 180℃ and the stirring speed is 800r / min. After the development is completed, waste mortar / SBS composite modified asphalt A3 is obtained.

[0075] Example 4

[0076] (1) Linear SBS modifier and star-shaped SBS modifier (linear SBS modifier accounts for 80 wt% of the total amount, and the linear SBS modifier has the following properties: the mass ratio of styrene to butadiene is 20:80, and the tensile strength is 300 kg / cm²) 2 The elongation at break is 820%, and the Shore hardness is 75HA. The star-shaped SBS modifier has the following properties: the mass ratio of styrene to butadiene is 40:60, and the tensile strength is 250 kg / cm². 2 A modifier with an elongation at break of 750% and a Shore hardness of 90HA was fed into a grinding mill and sheared and ground at 130℃ for 40 minutes until the two were evenly mixed. The evenly mixed modifier was then extruded and granulated three times. The first extrusion temperature was 125℃ and the screw speed was 200 r / min. The second extrusion temperature was 135℃ and the screw speed was 350 r / min. The third extrusion temperature was 155℃ and the screw speed was 500 r / min, thus obtaining a composite SBS modifier.

[0077] (2) Preparation of modified waste rubber sludge: a: Mix 100 parts of 60-mesh truck tire tread waste rubber powder (same as in Example 1) with 300 parts of aromatic oil (properties shown in Table 1) and 600 parts of Tarim River slag (properties shown in Table 2) evenly. During the stirring process, air is introduced for reaction, and the air flow rate is 0.06 m³ / min. 3 The reaction was carried out at a reaction rate of 100 rpm (kg·h) for 30 min, a reaction temperature of 145 °C, and a stirring speed of 800 rpm to obtain a pretreated mixture. b: The pretreated mixture obtained in a was mixed with 1 part diphenyl disulfide and 2 parts dithiothreitol, and then placed in a vacuum distillation vessel for vacuum distillation. The rotor speed inside the vessel was adjusted to 300 rpm, and the mass of the distillate was measured. Vacuum distillation was stopped when the distillate reached 700 parts (300 parts of residue at the bottom of the vessel). c: The residue at the bottom of the vessel obtained in b was subjected to high-speed shearing at a rate of 7500 rpm for 50 min at a temperature of 140 °C. Modified waste sludge was obtained after shearing.

[0078] (3) 100 parts of base bitumen (prepared by distillation of crude oil from sand and Kuwait crude oil in a 1:1 ratio, with a penetration of 70 0.1 mm at 25℃, a softening point of 48.6℃, a dynamic viscosity of 217 Pa·s at 60℃, and a residual ductility (10℃) of 8 cm, and by mass fraction, saturated components account for 14.8%, aromatic components account for 51.6%, resins account for 25.1%, and asphaltenes account for 8.5%) were heated to a fluid state at 140℃, and 0.7 parts of compatibilizer (resin obtained by solvent deasphalting process, with a kinematic viscosity of 60 mm at 100℃) were added. 2 / s, flash point is 212℃, by mass fraction, saturated fraction accounts for 33%, aromatic fraction accounts for 56.5%, resin accounts for 10%, asphaltene accounts for 0.5%; weight average molecular weight is 2090, molecular weight distribution width is 2.7. ), 1.8 parts of the composite SBS modifier prepared in step (1) and 25 parts of the modified waste sludge prepared in step (2) were subjected to high-speed shearing at 175℃ in N2 atmosphere for 60 min, with a shearing rate of 4000 r / min. After shearing, the mixture was stirred and developed at 175℃ for 30 min, with a stirring speed of 600 r / min.

[0079] (4) Slowly add 0.09 parts of stabilizer (elemental sulfur, ferrous chloride, tetramethylthiuram disulfide, wherein, by the total mass of the stabilizer, the content of elemental sulfur is 60%, the content of ferrous chloride is 10%, and the content of tetramethylthiuram disulfide is 30%) to the material in step (3). After 30 minutes, add another 0.09 parts of the same stabilizer. Each addition should be completed within 5 minutes. After the addition is completed, continue stirring and developing for 4 hours. The development temperature is 180℃ and the stirring speed is 800r / min. After the development is completed, waste mortar / SBS composite modified asphalt A4 is obtained.

[0080] Example 5

[0081] (1) Linear SBS modifier and star-shaped SBS modifier (linear SBS modifier accounts for 75 wt% of the total amount, and the linear SBS modifier has the following properties: the mass ratio of styrene to butadiene is 20:80, and the tensile strength is 300 kg / cm²) 2 The elongation at break is 820%, and the Shore hardness is 75HA. The star-shaped SBS modifier has the following properties: the mass ratio of styrene to butadiene is 40:60, and the tensile strength is 250 kg / cm². 2 A modifier with an elongation at break of 750% and a Shore hardness of 90HA was fed into a grinding mill and sheared and ground at 130℃ for 40 minutes until the two were evenly mixed. The evenly mixed modifier was then extruded and granulated three times. The first extrusion temperature was 125℃ and the screw speed was 200 r / min. The second extrusion temperature was 135℃ and the screw speed was 350 r / min. The third extrusion temperature was 155℃ and the screw speed was 500 r / min, thus obtaining a composite SBS modifier.

[0082] (2) Preparation of modified waste rubber sludge: a: Mix 100 parts of 60-mesh truck tire tread waste rubber powder (same as in Example 1) with 300 parts of aromatic oil (properties shown in Table 1) and 500 parts of Tarim River slag (properties shown in Table 2) evenly. During the stirring process, air is introduced for reaction, and the air flow rate is 0.06 m³ / min. 3 The reaction was carried out at a reaction rate of 145℃ for 30 minutes and a stirring speed of 800 r / min to obtain a pretreated mixture. b: The pretreated mixture obtained in a was mixed with 2 parts diphenyl disulfide and 3 parts dithiothreitol, and then placed in a vacuum distillation vessel for vacuum distillation. The rotor speed inside the vessel was adjusted to 300 r / min, and the mass of the distillate was measured. Vacuum distillation was stopped when the distillate reached 600 parts (300 parts of residue at the bottom of the vessel). c: The residue at the bottom of the vessel obtained in b was subjected to high-speed shearing at a rate of 8000 r / min for 50 minutes at a temperature of 140℃. Modified waste sludge was obtained after shearing.

[0083] (3) 100 parts of base bitumen (prepared by distillation of crude oil from sand and Kuwait crude oil in a 1:1 ratio, with a penetration of 70 0.1 mm at 25℃, a softening point of 48.6℃, a dynamic viscosity of 217 Pa·s at 60℃, and a residual ductility (10℃) of 8 cm, and by mass fraction, saturated components account for 14.8%, aromatic components account for 51.6%, resins account for 25.1%, and asphaltenes account for 8.5%) were heated to a fluid state at 140℃, and 0.8 parts of compatibilizer (resin obtained by solvent deasphalting process, with a kinematic viscosity of 60 mm at 100℃) were added. 2 / s, flash point is 212℃, by mass fraction, saturated fraction accounts for 33%, aromatic fraction accounts for 56.5%, resin accounts for 10%, asphaltene accounts for 0.5%; weight average molecular weight is 2090, molecular weight distribution width is 2.7. ), 1.8 parts of the composite SBS modifier prepared in step (1) and 23 parts of the modified waste sludge prepared in step (2) were subjected to high-speed shearing at 175℃ in N2 atmosphere for 60 min, with a shearing rate of 4000 r / min. After shearing, the mixture was stirred and developed at 175℃ for 30 min, with a stirring speed of 600 r / min.

[0084] (4) Slowly add 0.1 parts of stabilizer (elemental sulfur, nano zinc oxide, tetramethylthiuram disulfide, wherein, based on the total mass of the stabilizer, the content of elemental sulfur is 60%, the content of nano zinc oxide is 10%, and the content of tetramethylthiuram disulfide is 30%) to the material in step (3). After 30 minutes, add 0.06 parts of the same stabilizer. Each addition is completed within 5 minutes. After the addition is completed, continue stirring and developing for 3.5 hours. The development temperature is 180℃ and the stirring speed is 800r / min. After the development is completed, waste mortar / SBS composite modified asphalt A5 is obtained.

[0085] Comparative Example 1

[0086] Same as Example 1, except that no modified waste mortar is added during the preparation process to obtain modified asphalt B1.

[0087] Comparative Example 2

[0088] Same as Example 1, except that SBS is not added during the preparation process to obtain modified asphalt B2.

[0089] Comparative Example 3

[0090] Same as Example 1, except that no catalyst is added during the preparation of waste mortar to obtain modified asphalt B3.

[0091] Comparative Example 4

[0092] Same as Example 1, except that 500 parts of Tarim River slag were replaced with 500 parts of aromatic oil during the preparation of waste mortar to obtain modified asphalt B4.

[0093] Comparative Example 5

[0094] Same as Example 1, except that step (2) of preparing modified waste rubber sludge is as follows: a) Mix 100 parts of 60-mesh truck tire tread waste rubber powder (same as Example 1) with 300 parts of aromatic oil (properties shown in Table 1), 500 parts of Tarim River slag (properties shown in Table 2), 2 parts of diphenyl disulfide, and 2 parts of dithiothreitol. Place the mixture into a vacuum distillation vessel for vacuum distillation. Adjust the rotor speed inside the vessel to 300 r / min, and check the quality of the distillate. Distillation continues until the distillate reaches 600 parts (300 parts of residue at the bottom of the vessel). b) Perform high-speed shearing on the residue obtained in step a. The shearing rate is 7500 r / min, the shearing time is 50 min, and the shearing temperature is 140℃. Modified waste rubber sludge is obtained after shearing. Finally, modified asphalt B5 is obtained.

[0095] Comparative Example 6

[0096] Same as Example 1, except that in step (3) the modified waste mortar is replaced with an equal mass of 60-mesh rubber powder to obtain modified asphalt B6.

[0097] Comparative Example 7

[0098] Same as Example 1, except that in step (1), linear SBS modifier and star-shaped SBS modifier are directly added (linear SBS modifier accounts for 80 wt% of the total amount, and the linear SBS modifier has the following properties: the mass ratio of styrene to butadiene is 20:80, and the tensile strength is 300 kg / cm). 2 The elongation at break is 820%, and the Shore hardness is 75HA. The star-shaped SBS modifier has the following properties: the mass ratio of styrene to butadiene is 40:60, and the tensile strength is 250 kg / cm². 2 A composite SBS modifier was obtained by mechanically mixing a mixture with an elongation at break of 750% and a Shore hardness of 90 HA. The final modified asphalt, B7, was then obtained.

[0099] Test case

[0100] The main property indicators of the waste mortar / SBS composite modified asphalt obtained in the examples and comparative examples were tested, and the specific test results are shown in Table 3.

[0101] Table 1. Some properties of the aromatic-rich oils used in the examples and comparative examples.

[0102]

[0103]

[0104] Table 2 Properties of Tarim River slag used in the examples and comparative examples

[0105] <![CDATA[Density (20 °C) / (g / cm 3 )]]> 1.0211 Carbon residue value / wt% 24.1 Flash point (open cup) / °C 248 Carbon content / wt% 87.02 Hydrogen content / wt% 8.67 Sulfur content / wt% 2.86 Saturation fraction / % 29.8 Aromatic components / % 28.7 Gel content / % 19.4 Asphalt content / % 22.1 Nickel content (μg / g) 43.8 Vanadium content (μg / g) 271.1 <![CDATA[Kinematic viscosity (80 °C) / (mm 2 / s)]]> ＞20000 <![CDATA[Kinematic viscosity (100 °C) / (mm 2 / s)]]> 6596 Condensation Index (CI) 0.23

[0106] Table 3. Main properties of the modified asphalt obtained in the examples and comparative examples.

[0107]

[0108]

[0109] The main components that cause the irritating odor of asphalt fumes are sulfides and VOCs. To test these components, the asphalt sample was transferred into a sealed container (cylindrical, 25cm*25cm) with a gas extraction port and stored at 183℃ for 6 hours. After storage, the gas in the sealed container was extracted and stored in a gas bag. The content of sulfides and VOCs in the gas was tested using a gas chromatograph and a TVA-2020 VOC detector. The data obtained are shown in Table 4 below.

[0110] Table 4. Test data for sulfides and VOCs

[0111] Test sample Sulfide content / ppm (FID)VOCs / ppm A1 121 872 A2 124 869 A3 135 883 A4 129 877 A5 141 891 B1 102 839 B2 158 887 B3 139 894 B4 131 879 B5 179 906 B6 >max 1428 B7 134 902

[0112] The scope of protection of this invention is not limited to the above embodiments, but is defined by the claims. Those skilled in the art can make appropriate modifications to these embodiments without departing from the technical concept and spirit of this invention, and these modified embodiments are also included within the scope of protection of this invention.

Claims

1. A waste mortar / SBS composite modified asphalt, characterized in that, The waste mortar / SBS composite modified asphalt, by weight, comprises the following components: Base bitumen: 100 parts; Compatibilizer: 0.5 to 5 parts, preferably 0.5 to 2 parts; Composite SBS modifier: 1-3 parts, preferably 1-2.5 parts; Stabilizer: 0.1 to 0.4 parts, preferably 0.1 to 0.3 parts; Modified waste mortar: 12-30 parts, preferably 20-30 parts.

2. The waste mortar / SBS composite modified asphalt according to claim 1, characterized in that, The properties of the base asphalt include: a penetration of 68–74 mm at 25°C, a softening point of 47–49°C, a dynamic viscosity of 195 Pa·s–220 Pa·s at 60°C, and a residual ductility of 7–10 cm at 10°C. By mass fraction, the saturated components account for 12.8%–15.1%, the aromatic components account for 48.7%–52.3%, the resins account for 23.2%–27.6%, and the asphaltenes account for 7.1%–12.5%.

3. The waste mortar / SBS composite modified asphalt according to claim 1, characterized in that, The compatibilizer has the following properties: kinematic viscosity of 50 mmHg at 100°C. 2 / s~65mm 2 / s, flash point is 206℃~220℃, by mass fraction, saturated fraction accounts for 30%~42%, aromatic fraction accounts for 48%~57%, resin accounts for 8%~13%, asphaltene content is less than 2%; weight average molecular weight is 1990~2140, molecular weight distribution width is 1.6~3.

7.

4. The waste mortar / SBS composite modified asphalt according to claim 1, characterized in that, The composite SBS modifier includes a linear SBS modifier and a star-shaped SBS modifier; wherein the linear SBS modifier accounts for 60% to 85% of the total mass of the composite SBS modifier; the composite SBS modifier is an SBS modifier that has undergone pre-degradation extrusion treatment.

5. The waste mortar / SBS composite modified asphalt according to claim 1, characterized in that, The stabilizer includes a first stabilizer and a second stabilizer. The first stabilizer is elemental sulfur, and the second stabilizer is at least one of tetramethylthiuram disulfide, morpholino disulfide, ferric chloride, ferric oxide, ferrous chloride, copper chloride, nano zinc oxide, montmorillonite, and octadecyl alcohol 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate.

6. The waste mortar / SBS composite modified asphalt according to claim 1, characterized in that, The modified waste mortar includes waste rubber powder and composite filler oil.

7. The waste mortar / SBS composite modified asphalt according to claim 6, characterized in that, The waste rubber powder has the following properties by mass fraction: acetone-soluble portion accounts for 5.9wt% to 7.6wt%, natural rubber accounts for 46.1wt% to 48.4wt%, synthetic rubber accounts for 9.4wt% to 10.3wt%, carbon black accounts for 26.1wt% to 27.3wt%, and other fillers account for 6.2wt% to 8.4wt%. And / or, the waste rubber powder is obtained by crushing at least a portion of the tread, sidewall, and bead of the truck. And / or, the particle size of the waste adhesive powder is 20 mesh to 60 mesh, preferably 40 mesh to 60 mesh.

8. The waste mortar / SBS composite modified asphalt according to claim 6, characterized in that, The composite filler oil is an aromatic oil and ordinary residue; And / or, the properties of the aromatic-rich oil include: 27wt%–30wt% saturated components, 52wt%–60wt% aromatic components, 13wt%–19wt% resins, and 0wt%–0.2wt% asphaltenes, and the four-component analysis method is T0618-1993 Asphalt Chemical Component Test (Four-component Method); H ar 15wt%–17wt%, H α 25wt%–28wt%, H β accounting for 43wt%~46t%, H γ It accounts for 14wt% to 16wt%, with a C / H molar ratio of 0.82 to 0.88, an aromatic carbon fraction of 48wt% to 51wt%, a cycloalkane carbon fraction of 15wt% to 18wt%, and an alkyl carbon fraction of 35wt% to 37wt%. And / or, the properties of the slag include: a flash point of 246–258°C, a sulfur content of 2.77 wt%–3.63 wt%, and, by mass fraction, 26.1%–37.7% saturated matter, 20.2%–34.5% aromatic matter, 18.3%–24.8% resin, and 21.3%–30.1% asphaltenes, preferably 21.3%–25.0% asphaltenes; And / or, the ordinary slag also has the following basic properties: a residual carbon value of 19wt% to 28wt%, a total nickel and vanadium content of 310 to 365 μg / g, and a condensation index CI of 0.22 to 0.

30.

9. A method for preparing waste mortar / SBS composite modified asphalt according to any one of claims 1-8, comprising: (1) Preparation of composite SBS modifier; (2) Preparation of modified waste mortar; (3) Heat the base asphalt to a molten state, add composite SBS modifier, compatibilizer and modified waste mortar, shear, and stir to develop after shearing; (4) Add a stabilizer to the material obtained in step (3), continue stirring and developing, and finally obtain waste mortar / SBS composite modified asphalt.

10. The method according to claim 9, characterized in that, In step (1), the preparation process of the composite SBS modifier is as follows: linear SBS modifier and star-shaped SBS modifier are put into a grinding mill, sheared and ground, and extruded and granulated to obtain the composite SBS modifier.

11. The method according to claim 9, characterized in that, In step (2), the method for preparing the modified waste mortar includes: a: Mix waste rubber powder with aromatic oil and ordinary slag evenly, and introduce oxygen-containing gas during the stirring process to react and obtain a pretreated mixture; b: Mix the pretreated mixture obtained in step a with the catalyst and perform vacuum distillation; c: The residue at the bottom of the reactor obtained in step b is subjected to high-speed shearing to obtain modified waste sludge.

12. The method according to claim 11, characterized in that, In step a, the mass ratio of the waste rubber powder, aromatic oil, and ordinary residue is 1:(3-5):(5-8); And / or, in step a, the oxygen-containing gas is air, and the air flow rate is 0.02–0.11 m³ / s. 3 / (kg·h), reaction time is 20–40 min, reaction temperature is 120–150 °C, and stirring speed is 700–900 r / min.

13. The method according to claim 11, characterized in that, In step b, the catalyst is one or more of 3,6-dioxa-1,8-octanedithiol, dithiothreitol, hexadecylamine, and 2,2-dibenzoylaminodiphenyldisulfide and diphenyl disulfide. And / or, in step b, the mass ratio of the waste adhesive powder to the catalyst is 100:(3-8); And / or, in step b, the vacuum distillation is carried out in a vacuum distillation kettle; the conditions for the vacuum distillation are: vacuum distillation until the mass ratio of the residue at the bottom of the kettle to the initially added gum powder is 1:(0.2~0.5), and the rotor speed inside the vacuum distillation kettle during the vacuum distillation process is 100~300 r / min.

14. The method according to claim 11, characterized in that, In step c, the shearing rate is 6000-8000 r / min, the shearing time is 40-80 min, and the shearing temperature is 130-150℃.

15. The method according to claim 9, characterized in that, In step (3), the heating temperature of the base asphalt is 140-155℃; the shearing and stirring development are both carried out under a protective gas, preferably an inert gas and / or N2; the shearing rate is 4000-6000 r / min, preferably 4000-5500 r / min, the shearing time is 60-80 min, and the temperature required for shearing is 170-185℃; the stirring speed is 600-800 r / min, the development time is 20-40 min, and the development temperature is 160℃-195℃, preferably 170℃-180℃.

16. The method according to claim 9, characterized in that, In step (4), the stabilizer is added in several batches, with an interval of 20 to 40 minutes between each addition; preferably, it is added in two batches; the stirring speed is 600 to 800 r / min, the development time is 3 to 4 hours, and the development temperature is 170°C to 195°C, preferably 175°C to 185°C.

17. The application of the waste mortar / SBS composite modified asphalt according to any one of claims 1-8 or the waste mortar / SBS composite modified asphalt prepared by any one of claims 9-16 in road asphalt.

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