Preparation method of reclaimed asphalt masterbatch based on RAP

Abstract

The present application relates to the technical field of regenerated asphalt masterbatch preparation, and particularly relates to a regenerated asphalt masterbatch preparation method based on RAP, which comprises the following steps: recovering waste asphalt mixture, crushing, drying, centrifugal extraction, separating waste aggregate and asphalt, and detecting asphalt content to meet the preparation requirements of regenerated masterbatch; mixing hard asphalt and target asphalt in a reaction kettle, adjusting stirring parameters according to the difference between the upper and lower Brookfield viscosities of the colloid to prepare target base colloid, adding a composite regeneration repair agent, and respectively determining the addition amounts of a compatibilizer and an anti-aging agent according to the Brookfield viscosity and the penetration, and finally preparing target regenerated asphalt masterbatch. Through the process of adjusting the blowing flow, blowing pressure, stirring speed and blade stirring angle by comparing the actual Brookfield viscosities of the upper and lower zones in the reaction kettle, the problem that the viscosity uniformity of the subsequent base regenerated asphalt masterbatch is difficult to control due to the uneven stirring of the target base colloid is solved.

Description

Technical Field

[0001] This invention relates to the field of recycled asphalt masterbatch preparation technology, and in particular to a method for preparing recycled asphalt masterbatch based on RAP blending. Background Technology

[0002] Recycled asphalt mixtures are asphalt mixtures made by remixing old asphalt pavement with recycling agents, new asphalt materials, and new aggregates in a certain proportion after the old asphalt pavement has been excavated, recycled, crushed, and screened. The aged asphalt in waste asphalt has high hardness and viscosity; its addition improves the mixture's resistance to rutting, making it particularly suitable for high-temperature areas or heavy-load roads. It reduces the risk of road surface deformation in summer, while significantly reducing the amount of new asphalt and aggregates used, thus reducing mining and asphalt production and lowering carbon emissions.

[0003] Chinese Patent Publication No. CN120737623A discloses a waste asphalt recycler and a method for preparing a large proportion of waste asphalt containing the same. The raw materials for preparing the waste asphalt recycler, by mass fraction, include 45-55% epoxidized waste cooking oil, 15-20% furfural refined oil, 8-12% methyl carbamate, 3-5% nano-mica powder, 10-15% desulfurized rubber powder, and 5-8% SEBS modifier. The waste asphalt recycler has a three-dimensional network structure formed by polar bonding. By mass fraction, the large proportion of waste asphalt includes 70-90 parts waste asphalt, 15-25 parts limestone sand, 10.5-18 parts of the waste asphalt recycler, 1-5 parts new asphalt, and 0.05-0.15 parts long-chain aliphatic hydrocarbon warm mix agent. The regenerator of this invention can act inside the molecules of waste asphalt, forming a stable spatial structure with elasticity and a three-dimensional network through the synergistic effect of multiple components. Through the chemical bond interaction between the components, the waste asphalt maintains good low-temperature crack resistance and performance stability after regeneration.

[0004] Therefore, the existing technology has the following problems: In the process of preparing recycled asphalt masterbatch, due to the lack of a process for adjusting the air flow rate, air pressure, stirring speed and blade stirring angle based on the comparison results of the actual Brookfield viscosity in the upper and lower sections of the reactor, the target base colloid is not stirred evenly, which makes it difficult to control the viscosity uniformity of the subsequent base recycled asphalt masterbatch, resulting in local areas that are too thin or too thick. Summary of the Invention

[0005] Therefore, this invention provides a method for preparing recycled asphalt masterbatch based on RAP, which overcomes the problem in the prior art that, in the process of preparing recycled asphalt masterbatch, the lack of a process for adjusting the blowing flow rate, blowing pressure, stirring speed and blade stirring angle based on the comparison results of the actual Brookfield viscosity in the upper and lower sections of the reactor makes it difficult to control the viscosity uniformity of the subsequent base recycled asphalt masterbatch due to uneven stirring of the target base colloid, resulting in local excessively thin or thick areas.

[0006] To achieve the above objectives, the present invention provides a method for preparing recycled asphalt masterbatch based on RAP, comprising:

[0007] The waste asphalt mixture is crushed and dried to obtain a dry waste asphalt mixture. The dry waste asphalt mixture is then centrifuged and extracted to obtain waste aggregate and waste asphalt.

[0008] The asphalt content in waste asphalt is detected to obtain the actual asphalt content. The actual asphalt content is compared with the asphalt content threshold range to determine whether the waste asphalt mixture meets the requirements for the preparation of recycled asphalt masterbatch.

[0009] Based on the mixing of hard asphalt masterbatch and target asphalt in the reactor, an initial base colloid is obtained. The Brinell viscosity of the base colloid at 150°C is measured to obtain the actual Brinell viscosity of the zone. The actual Brinell viscosity of the upper zone is compared with that of the lower zone to determine the difference between the actual Brinell viscosity of the zones. Based on the comparison result between the difference and the difference threshold, the stirring parameters of the reactor stirring device are determined.

[0010] The target base colloid is obtained by stirring based on the determined stirring parameters;

[0011] The composite regeneration and repair agent is added to the target base colloid and heated and stirred to obtain the base recycled asphalt masterbatch. The asphalt content of the masterbatch is tested to adjust the amount of composite regeneration and repair agent added.

[0012] The amount of compatibilizer added is determined based on the adjusted actual Brinell viscosity, and the amount of composite anti-aging agent added is determined based on the penetration of the base recycled asphalt masterbatch, so as to obtain the target recycled asphalt masterbatch.

[0013] The 150℃ Brookfield viscosity refers to the fluid viscosity value of the base colloid measured by a Brookfield viscometer under test conditions of 150℃. The stirring parameters include the air flow rate, air pressure, stirring speed, and blade stirring angle of the bottom air distribution device.

[0014] Furthermore, the process of determining whether waste asphalt mixtures meet the requirements for preparing recycled asphalt masterbatch includes:

[0015] Based on the fact that the actual asphalt content is less than the minimum value of the asphalt content threshold range, the amount of waste asphalt mixture is increased according to the difference between the minimum value of the asphalt content threshold range and the actual asphalt content.

[0016] Based on the actual asphalt content being within the asphalt content threshold range, the current amount of waste asphalt mixture will be maintained.

[0017] Based on the fact that the actual asphalt content is greater than the maximum value of the asphalt content threshold range, the amount of waste asphalt mixture is reduced according to the difference between the actual asphalt content and the maximum value of the asphalt content threshold range.

[0018] Furthermore, the process for obtaining the actual Brinell viscosity of the partition includes:

[0019] The initial basic colloid in the reactor is divided into upper and lower basic colloid regions. The actual Brinell viscosity of the upper and lower basic colloid regions is detected to obtain the actual Brinell viscosity of each region.

[0020] Furthermore, the process of determining the difference in actual Brinell viscosity between the zones includes:

[0021] Based on the comparison between the actual Brinell viscosity of the upper partition and the actual Brinell viscosity of the lower partition, the difference in the actual Brinell viscosity of the partition is determined.

[0022] Furthermore, the process of determining the agitation parameters of the reactor agitator includes:

[0023] Based on the difference being less than or equal to the difference threshold, the agitation parameters are not adjusted;

[0024] Based on the fact that the difference is greater than the difference threshold, the stirring parameters are adjusted according to the comparison results between the actual Brinell viscosity of the upper zone and the actual Brinell viscosity of the lower zone.

[0025] Furthermore, the process of adjusting the stirring parameters based on the comparison between the actual Brinell viscosity of the upper zone and the actual Brinell viscosity of the lower zone includes:

[0026] Based on the fact that the actual Brinell viscosity of the upper zone is less than that of the lower zone, the stirring speed of the stirring device at the top of the reactor is increased according to the difference between the actual Brinell viscosity of the lower zone and the actual Brinell viscosity of the upper zone.

[0027] Based on the fact that the actual Brinell viscosity of the upper zone is greater than that of the lower zone, the blowing flow rate of the bottom gas distribution device at the bottom of the reactor is increased according to the difference between the actual Brinell viscosity of the upper zone and the actual Brinell viscosity of the lower zone.

[0028] Furthermore, the process of adjusting the stirring parameters based on the comparison between the actual Brinell viscosity of the upper zone and the actual Brinell viscosity of the lower zone also includes:

[0029] Based on the maximum stirring speed of the stirring device, the blowing pressure of the bottom air distribution device is increased according to the difference between the actual Brinell viscosity of the lower zone and the actual Brinell viscosity of the upper zone.

[0030] Based on the maximum blowing flow rate achieved by the bottom air distribution device, the stirring angle of the stirring device blades is increased according to the difference between the actual Brinell viscosity of the upper zone and the actual Brinell viscosity of the lower zone.

[0031] Wherein, the blade stirring angle is the angle between the stirring blade and the horizontal plane.

[0032] Furthermore, the process of adjusting the amount of the composite regeneration and repair agent added includes:

[0033] Based on the fact that the asphaltene content of the masterbatch is less than the minimum value of the threshold range of masterbatch asphaltene content, the amount of composite regeneration and repair agent added is increased according to the difference between the minimum value of the threshold range of masterbatch asphaltene content and the masterbatch asphaltene content.

[0034] Based on the fact that the asphaltene content of the masterbatch is within the threshold range of the masterbatch asphaltene content, the current amount of composite regeneration and repair agent is maintained;

[0035] Based on the fact that the asphaltene content of the masterbatch is greater than the maximum value of the threshold range of masterbatch asphaltene content, the amount of composite regeneration and repair agent added is reduced according to the difference between the masterbatch asphaltene content and the maximum value of the threshold range of masterbatch asphaltene content.

[0036] Furthermore, the process of determining the amount of compatibilizer added includes:

[0037] The actual Brinell viscosity of the base recycled asphalt masterbatch after adjusting the amount of composite recycling repair agent is detected, and the adjusted actual Brinell viscosity is obtained. The amount of compatibilizer added is determined by comparing the adjusted actual Brinell viscosity with the preset Brinell viscosity threshold range of recycled asphalt masterbatch.

[0038] Based on the fact that the adjusted actual Brinell viscosity is less than the minimum value of the Brinell viscosity threshold range, the amount of compatibilizer added is reduced according to the difference between the adjusted actual Brinell viscosity and the minimum value of the Brinell viscosity threshold range.

[0039] Based on the fact that the adjusted actual Brinell viscosity is within the Brinell viscosity threshold range, the current compatibilizer addition amount is maintained;

[0040] Based on the fact that the adjusted actual Brinell viscosity is greater than the maximum value of the Brinell viscosity threshold range, the amount of compatibilizer added is increased according to the difference between the adjusted actual Brinell viscosity and the maximum value of the Brinell viscosity threshold range.

[0041] Furthermore, the process of determining the amount of composite anti-aging agent to be added includes:

[0042] The penetration at 25°C of the base recycled asphalt masterbatch is tested to obtain the actual penetration, and the actual penetration is compared with the preset penetration threshold range.

[0043] Based on the fact that the actual penetration is less than the minimum value of the penetration threshold range, the amount of compound anti-aging agent added is increased according to the difference between the minimum value of the penetration threshold range and the actual penetration.

[0044] Based on the actual penetration being within the penetration threshold range, maintain the current amount of compound anti-aging agent added.

[0045] Based on the fact that the actual penetration is greater than the maximum value of the penetration threshold range, the amount of compound anti-aging agent added is reduced according to the difference between the actual penetration and the maximum value of the penetration threshold range.

[0046] Compared with existing technologies, the advantages of this invention lie in its ability to efficiently separate waste asphalt and waste aggregates through standardized crushing, drying, and centrifugal extraction of waste asphalt mixtures, fully recovering waste asphalt, achieving recycling of waste materials, and reducing resource waste. Through reasonable extraction, washing, and distillation processes, impurities and residual extractants are effectively removed, ensuring the purity of the recovered waste asphalt and waste aggregates, providing high-quality raw materials for subsequent preparation steps, ensuring the stability of subsequent processes, and guaranteeing the final product's performance meets standards. The entire process is standardized and simple to operate, enabling precise separation and separate recycling of waste asphalt and aggregates, improving the utilization rate of waste resources, and achieving both environmental and economic benefits.

[0047] Furthermore, standardized testing methods are employed to accurately detect the asphaltene content in waste asphalt. Multiple parallel experiments and constant-weight operations ensure the reliability and accuracy of the test results, providing a scientific basis for determining whether waste asphalt mixtures are suitable for preparing recycled asphalt masterbatch. Based on the comparison between the actual asphaltene content obtained from the tests and the preset threshold range, the amount of waste asphalt mixture is dynamically adjusted according to the content difference, achieving precise control of the dosage and ensuring that the total asphaltene content of the waste asphalt meets the preparation requirements. This process effectively avoids problems such as unstable subsequent preparation processes and substandard product performance caused by abnormal asphaltene content, improving the controllability and stability of the process. It lays a solid foundation for subsequent processes such as basic colloid formulation and additive dosage adjustment, ensuring the final quality of the recycled asphalt masterbatch.

[0048] Furthermore, by scientifically dividing the initial basic colloid in the reactor, the Brookfield viscosity of the upper and lower sections was accurately detected, and the actual Brookfield viscosity of each section was obtained, providing precise data support for subsequent adjustment of stirring parameters. The standardized preparation process of the basic colloid ensures the initial uniformity of the colloid and reduces detection deviations caused by uneven mixing of raw materials. The reasonable sampling operation of the partitioning method ensures the representativeness and reliability of the viscosity detection results, avoids parameter judgment errors caused by improper sampling, and can promptly detect colloid stratification problems, laying a solid foundation for subsequent optimization of stirring parameters and improvement of the uniformity of the target basic colloid.

[0049] Furthermore, by scientifically calculating the difference in actual Brinell viscosity between zones and combining it with preset thresholds to accurately determine the adjustment requirements of stirring parameters, on-demand control of stirring parameters is achieved, avoiding energy waste and process instability caused by blind adjustment. Based on the viscosity comparison results of the upper and lower zones, different adjustment methods are adopted to efficiently solve the problem of colloid stratification, accurately improve colloid uniformity, effectively improve the mixing quality of the target base colloid, and avoid the problems of abnormal subsequent preparation processes and substandard product performance caused by colloid stratification.

[0050] Furthermore, a progressive agitation parameter adjustment scheme is provided for the operating conditions where the agitator reaches its performance limit. This overcomes the limitations of a single adjustment method and achieves comprehensive and in-depth control of colloid uniformity. By adjusting the blowing pressure of the bottom gas distribution device or the stirring angle of the agitator blades based on the viscosity difference between the upper and lower zones, the problem of colloid stratification can be effectively solved when the stirring speed or gas distribution flow rate reaches its maximum value and cannot be adjusted further. This ensures that the uniformity of the target base colloid meets the standard, avoids the process bottleneck caused by a single adjustment method, and improves the flexibility and adaptability of the preparation process.

[0051] Furthermore, by detecting the actual asphaltene content of the base recycled asphalt masterbatch and combining it with preset threshold ranges and content differences, targeted adjustments to the dosage of the repair agent can be made to effectively control the asphaltene content of the masterbatch within a reasonable range, avoiding unsuitable hardness and performance damage caused by abnormal asphaltene content. This process standardizes the adjustment logic of the repair agent dosage and clarifies the adjustment basis, fully leveraging the regeneration and repair function of the composite recycled repair agent while avoiding waste or insufficient dosage of the repair agent, ensuring that the final recycled asphalt masterbatch meets road performance standards, and simultaneously improving the recycling rate of waste asphalt.

[0052] Furthermore, by detecting and adjusting the Brookfield viscosity of the masterbatch, and combining the preset threshold range and viscosity difference, targeted operations such as increasing, decreasing, or maintaining the amount of compatibilizer can be taken to effectively control the masterbatch viscosity within the construction compatibility range, avoid construction problems caused by abnormal viscosity, fully utilize the effect of compatibilizer in reducing viscosity and improving compatibility, and avoid resource waste or masterbatch performance defects caused by improper use of compatibilizer.

[0053] Furthermore, by standardizing the testing of the masterbatch penetration and combining it with the preset threshold range and penetration difference, targeted measures can be taken to increase, decrease, or maintain the dosage of anti-aging agent. This can effectively control the hardness of the masterbatch and avoid road performance defects caused by the masterbatch being too soft or too hard. This fully utilizes the effect of anti-aging agent in inhibiting asphalt aging while avoiding performance imbalance and resource waste caused by improper dosage of anti-aging agent. Attached Figure Description

[0054] Figure 1This is a flowchart of the method for preparing recycled asphalt masterbatch based on RAP as described in this embodiment;

[0055] Figure 2 This is a flowchart illustrating the process of determining whether waste asphalt mixture meets the requirements for preparing recycled asphalt masterbatch in this embodiment.

[0056] Figure 3 This is a flowchart illustrating the process of determining the stirring parameters of the reactor stirring device in this embodiment;

[0057] Figure 4 This is a schematic diagram of the stirring device inside the reactor in this embodiment.

[0058] In the diagram, 1-rotating rod; 2-stirring blade; 3-gas distribution pipe; 4-reaction vessel. Detailed Implementation

[0059] To make the objectives and advantages of the present invention clearer, the present invention will be further described below with reference to embodiments; it should be understood that the specific embodiments described herein are merely for explaining the present invention and are not intended to limit the present invention.

[0060] Preferred embodiments of the present invention will now be described with reference to the accompanying drawings. Those skilled in the art should understand that these embodiments are merely illustrative of the technical principles of the present invention and are not intended to limit the scope of protection of the present invention.

[0061] It should be noted that in the description of this invention, the terms "upper", "lower", "left", "right", "inner", "outer", etc., which indicate directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings. This is only for the convenience of description and is not intended to indicate or imply that the device or element must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation of this invention.

[0062] Furthermore, it should be noted that, in the description of this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0063] Please see Figure 1 As shown, it is a flowchart of the method for preparing recycled asphalt masterbatch based on RAP in this embodiment;

[0064] This embodiment provides a method for preparing recycled asphalt masterbatch based on RAP, including:

[0065] Step S1: The waste asphalt mixture is crushed and dried to obtain a dry waste asphalt mixture. The dry waste asphalt mixture is then centrifuged and extracted to obtain waste aggregate and waste asphalt.

[0066] Step S2: Detect the asphalt content in waste asphalt to obtain the actual asphalt content, and compare the actual asphalt content with the asphalt content threshold range to determine whether the waste asphalt mixture meets the requirements for preparing recycled asphalt masterbatch.

[0067] Step S3: Based on the mixing of hard asphalt masterbatch and target asphalt in the reactor, an initial base colloid is obtained. The Brinell viscosity of the base colloid at 150°C is detected to obtain the actual Brinell viscosity of the partition. The actual Brinell viscosity of the upper partition is compared with that of the lower partition to determine the difference between the actual Brinell viscosity of the partition. Based on the comparison result between the difference and the difference threshold, the stirring parameters of the reactor stirring device are determined.

[0068] Step S4: Stir based on the determined stirring parameters to obtain the target base colloid;

[0069] Step S5: Add the composite recycling repair agent to the target base colloid and perform heating and stirring operations to obtain the base recycled asphalt masterbatch. Detect the asphalt content of the base recycled asphalt masterbatch to adjust the amount of composite recycling repair agent added.

[0070] Step S6: Determine the amount of compatibilizer to be added based on the adjusted actual Brinell viscosity, and determine the amount of composite anti-aging agent to be added based on the penetration of the base recycled asphalt masterbatch, so as to obtain the target recycled asphalt masterbatch.

[0071] The 150℃ Brookfield viscosity refers to the fluid viscosity value of the base colloid measured by a Brookfield viscometer under test conditions of 150℃. The stirring parameters include the air flow rate, air pressure, stirring speed, and blade stirring angle of the bottom air distribution device.

[0072] In this embodiment of the invention, in step S1, the waste asphalt mixture is crushed to a particle size ≤19mm and fed into a drum dryer to dry at a drying temperature of 120-130℃ and a rotation speed of 5-8r / min. Its moisture content is tested to be ≤0.5%, and a dried waste asphalt mixture with a mass of 1000g is obtained. RAP is waste asphalt mixture.

[0073] Petroleum ether was selected as the extractant. A high-speed refrigerated centrifuge was used. The obtained dried waste asphalt mixture was placed in a clean extraction container, and petroleum ether was slowly poured in. The mixture was stirred at a constant speed with a glass rod for 5 minutes to ensure that each particle of dried waste asphalt mixture was fully impregnated with petroleum ether, so that the waste asphalt on the surface and inside of the mixture was initially dissolved in the petroleum ether. The impregnation temperature was controlled at 25±2℃. The mass ratio of petroleum ether to dried waste asphalt mixture was 3:1. The extraction container containing the mixture was placed in the centrifuge rotor, and the centrifugation speed was 8000 r / min, the centrifugation temperature was 20±2℃, and the centrifugation time was 20 minutes. After the operation is completed, remove the extraction container and slowly aspirate the petroleum ether extract containing dissolved waste asphalt from the upper layer with a pipette. Transfer the extract to another clean container. Rinse the remaining waste aggregate at the bottom of the extraction container 2-3 times with a small amount of petroleum ether. Add the rinsing solution to the above extract to ensure that the waste asphalt adhering to the surface of the aggregate is completely washed off and fully recovered. Place the rinsed waste aggregate into a vacuum filter to remove the residual extractant on the surface. Then place it in a drying oven and dry it at 105°C for 30 minutes to remove the residual extractant. After drying, remove it and cool it to room temperature to obtain pure waste aggregate. Weigh it to 892.5g.

[0074] The collected petroleum ether extract was placed in a distillation apparatus, and the distillation temperature was controlled at 75±5℃. The petroleum ether was recovered. Distillation was stopped when no more extractant was distilled out. The remaining viscous substance was waste asphalt. After cooling to room temperature, it was taken out and weighed, which was 102.3g.

[0075] By standardizing the crushing, drying, and centrifugal extraction processes of waste asphalt mixtures, efficient separation of waste asphalt and waste aggregates is achieved, fully recovering waste asphalt and realizing the recycling of waste materials, thus reducing resource waste. Through reasonable extraction, washing, and distillation processes, impurities and residual extractants are effectively removed, ensuring the purity of the recovered waste asphalt and waste aggregates. This provides high-quality raw materials for subsequent preparation steps, ensuring the stability of subsequent processes and the final product meeting performance standards. The entire process is standardized and simple to operate, enabling precise separation and separate recycling of waste asphalt and aggregates, improving the utilization rate of waste resources, and achieving both environmental and economic benefits.

[0076] Please see Figure 2 As shown, it is a flowchart of the process for determining whether the waste asphalt mixture meets the requirements for the preparation of recycled asphalt masterbatch in this embodiment;

[0077] Specifically, the process of determining whether waste asphalt mixtures meet the requirements for preparing recycled asphalt masterbatch includes:

[0078] Based on the fact that the actual asphalt content is less than the minimum value of the asphalt content threshold range, the amount of waste asphalt mixture is increased according to the difference between the minimum value of the asphalt content threshold range and the actual asphalt content.

[0079] Based on the actual asphalt content being within the asphalt content threshold range, the current amount of waste asphalt mixture will be maintained.

[0080] Based on the fact that the actual asphalt content is greater than the maximum value of the asphalt content threshold range, the amount of waste asphalt mixture is reduced according to the difference between the actual asphalt content and the maximum value of the asphalt content threshold range.

[0081] In step S2, the asphaltene content in waste asphalt is determined using the n-heptane precipitation method. The waste asphalt is placed in a drying oven and heated at a constant temperature of 80±2℃ for 10 minutes to melt it into a fluid state. The n-heptane, beaker, and sintered glass funnel are then dried in a desiccator to constant weight. 2g of the melted waste asphalt sample is weighed into the beaker and recorded as m0. 100mL of n-heptane is then added to the beaker, and the mixture is stirred with a glass rod until the waste asphalt sample is completely dissolved, yielding a waste asphalt-n-heptane mixed solution. During stirring, the beaker can be placed in a constant temperature water bath at 40±2℃ to aid dissolution. The time should not exceed 15 minutes to avoid the volatilization of n-heptane. Let the waste asphalt-n-heptane mixture stand for 24 hours at a temperature of 25±2℃ to allow the asphalt in the mixture to fully precipitate. Since asphalt is insoluble in n-heptane, it can be separated by precipitation. Slowly pour the settled mixture and precipitate into a sand core funnel, labeled m1. Slowly rinse the inner wall of the beaker and the sand core funnel with n-heptane until the rinsing liquid is colorless and transparent, ensuring that the unprecipitated asphalt components are completely rinsed away, leaving only the asphalt precipitate. Control the amount of n-heptane used during the rinsing process to avoid waste and prevent excessive rinsing force from causing the precipitate to be lost.

[0082] Place the sand core funnel containing asphalt precipitate into a drying oven and dry it at 105±2℃ for 2 hours. After removing it, place it in a desiccator to cool to room temperature for at least 30 minutes. Then weigh the total mass of the sand core funnel and asphalt precipitate and record it as m2. Repeat the drying, cooling and weighing steps until the mass difference between two weighings is ≤0.0002g, which is considered constant weight. This ensures that there is no residual n-heptane in the asphalt and improves the detection accuracy.

[0083] Actual asphalt content = [(m2-m1) / m0]×100%, where m0 is the mass of the waste asphalt sample, m1 is the constant weight mass of the sand core funnel, and m2 is the total constant weight mass of the sand core funnel and the asphalt precipitate.

[0084] To ensure the reliability of the test results, three parallel experiments were conducted simultaneously. The same mass of waste asphalt samples were used in the three experiments, and the above steps were performed synchronously. The actual asphalt content of each group was calculated. When the relative average deviation of the three experimental results was ≤0.2%, the average value of the three results was taken as the final actual asphalt content.

[0085] In this embodiment of the invention, the results of the three parallel experiments were 12.35%, 12.38%, and 12.36%, respectively, with a relative average deviation of 0.12%, which meets the requirements for detection accuracy. Finally, the actual asphalt content of the waste asphalt was determined to be 12.36%.

[0086] In this embodiment of the invention, the threshold range for asphaltene content is set to 10.00%-14.00%;

[0087] If the actual asphalt content is less than the minimum value of the asphalt content threshold range, the amount of waste asphalt mixture is increased based on the difference between the minimum value of the asphalt content threshold range and the actual asphalt content.

[0088] If the actual asphalt content is 9.20%, then the difference between the minimum value of the asphalt content threshold range and the actual asphalt content is 10.00% - 9.20% = 0.80%. According to the preset dosage adjustment coefficient of 0.8g / g, that is, for every 1% difference in asphalt content, the corresponding waste asphalt mixture dosage for 1g of waste asphalt is adjusted to 0.8g. The calculation of the amount of waste asphalt mixture to be added is: 1000g × (0.80% / 12.36%) × 0.8 ≈ 51.8g. The total amount of waste asphalt mixture after adjustment is 1000g + 51.8g = 1051.8g, ensuring that the total asphalt content of the waste asphalt after adjustment meets the preparation requirements. Among them, 1000g is the initial amount of dry waste asphalt mixture used.

[0089] If the actual asphalt content is greater than the maximum value of the asphalt content threshold range, the amount of waste asphalt mixture should be reduced based on the difference between the actual asphalt content and the maximum value of the asphalt content threshold range.

[0090] If the actual asphalt content is 14.80%, then the difference between the actual asphalt content and the maximum value of the asphalt content threshold range is 14.80% - 14.00% = 0.80%. According to the preset dosage adjustment coefficient of 0.8g / g, that is, for every 1% difference in asphalt content, the corresponding waste asphalt mixture dosage for 1g of waste asphalt is adjusted to 0.8g. The waste asphalt mixture dosage to be reduced is: 1000g × (0.80% / 12.36%) × 0.8 ≈ 51.8g. After adjustment, the total waste asphalt mixture dosage is 1000g - 51.8g = 948.2g.

[0091] Standardized testing methods are employed to accurately detect the asphaltene content in waste asphalt. Multiple parallel experiments and constant-weight operations ensure the reliability and accuracy of the test results, providing a scientific basis for determining whether waste asphalt mixtures are suitable for preparing recycled asphalt masterbatch. Based on the comparison between the actual asphaltene content and the preset threshold range, the amount of waste asphalt mixture is dynamically adjusted according to the content difference, achieving precise dosage control and ensuring that the total asphaltene content of the waste asphalt meets the preparation requirements. This process effectively avoids problems such as unstable subsequent preparation processes and substandard product performance caused by abnormal asphaltene content, improving the controllability and stability of the process. It lays a solid foundation for subsequent processes such as basic colloid formulation and additive dosage adjustment, ensuring the final quality of the recycled asphalt masterbatch.

[0092] Specifically, the process of obtaining the actual Brinell viscosity of the partition includes:

[0093] The initial basic colloid in the reactor is divided into upper and lower basic colloid regions. The actual Brinell viscosity of the upper and lower basic colloid regions is detected to obtain the actual Brinell viscosity of each region.

[0094] 102.3g of waste asphalt was recovered from 1000g of dried waste asphalt mixture. This waste asphalt was then combined with hard asphalt masterbatch and target asphalt in a reactor to obtain an initial base colloid. The initial base colloid was then divided into zones, and the Brookfield viscosity at 150℃ was measured in both the upper and lower zones to obtain the actual Brookfield viscosity for each zone. Based on the recovered 102.3g of waste asphalt, with an actual asphaltene content of 12.36%, hard asphalt masterbatch and target asphalt (No. 90 road petroleum asphalt) were mixed according to the specified mass ratio.

[0095] In this embodiment of the invention, a standard mix ratio of hard asphalt masterbatch to No. 90 road petroleum asphalt is used, with a total input of 80 kg, including 48 kg of hard asphalt masterbatch and 32 kg of No. 90 road petroleum asphalt. This mix ratio is for preparing a viscosity of 4000-5000 mPa at 150°C. The reference ratio of the s-based colloid is suitable for the corresponding capacity of the reactor. The loading amount is controlled at 10%-20% of the reactor volume to avoid overflow during mixing and to ensure uniform stirring.

[0096] Start the temperature control system of the reactor and preheat the inner wall of the reactor to 140±2℃ for 30 minutes to avoid the asphalt raw material from adhering and mixing unevenly due to cold walls. At the same time, it lays the temperature foundation for the subsequent 150℃ Brookfield viscosity test. The weighed waste asphalt, hard asphalt masterbatch and target asphalt are slowly added to the preheated reactor in sequence. The initial stirring speed is set to 450 r / min, the stirring temperature is 150±1℃ and the stirring time is 20 minutes to form a uniform initial base colloid. After stirring, keep the temperature inside the reactor stable at 150±1℃ and let it stand for 10 minutes to eliminate the air bubbles generated during stirring and avoid the air bubbles affecting the subsequent viscosity test results.

[0097] Based on the actual liquid level of the initial basic colloid in the reactor, the initial basic colloid in the reactor was divided into two equal regions, namely, the upper region of the basic colloid is 0-30cm below the liquid level and the lower region of the basic colloid is 30-60cm below the liquid level.

[0098] The actual Brinell viscosity of the initial base colloid in the upper and lower base colloid regions was measured using a Brinell viscometer. The measurement temperature was set to 150±0.1℃. Two clean, dry sampling tubes, 25cm and 45cm in length, were prepared to accommodate sampling from the upper and lower regions. The sampling tubes were preheated in a 150℃ constant temperature oven for 10 minutes to prevent the colloid from cooling and changing in viscosity due to excessively low sampling tube temperature. Clean beakers and thermometers were also prepared and preheated to 150±2℃. Using a preheated 25cm sampling tube, slowly insert it 15cm into the upper partition of the reaction vessel, ensuring the tube is positioned in the center of the upper partition for representative sampling. Slowly extract approximately 50mL of the upper partition colloidal sample and slowly inject it into a preheated beaker. Place the upper partition colloidal sample in the beaker on the testing platform of a Brookfield viscometer and start the viscometer to measure the viscosity. Read the viscosity value every 10 seconds for three consecutive measurements. Record the three readings as follows: 4200 mPa. s, 4210mPa s, 4190mPa s, take the average value as the actual Brinell viscosity of the basic colloid in the upper zone, 4200;

[0099] Lower partition basic colloidal region: Using a preheated 45cm sampling tube, slowly insert it into the lower partition basic colloidal region of the reactor to a depth of 35cm, ensuring the sampling tube is located in the middle of the lower partition for representative sampling. Slowly extract approximately 50mL of the lower partition colloidal sample and slowly inject it into a preheated beaker. Place the lower partition colloidal sample in the beaker on the detection platform of the Brookfield viscometer and start the viscometer using the same parameters as for the upper partition basic colloidal region. Read the viscosity value every 10 seconds, and perform three consecutive measurements. The measured data are: 4800mPa. s, 4810mPa s, 4790mPa s, taking the average value as the actual Brinell viscosity of the lower partition's basic colloid, 4800 mPa. s.

[0100] By scientifically dividing the initial basic colloid in the reactor, the Brookfield viscosity of the upper and lower sections is accurately detected and the actual Brookfield viscosity of each section is obtained, providing precise data support for subsequent adjustment of stirring parameters. The standardized preparation process of the basic colloid ensures the initial uniformity of the colloid and reduces detection deviations caused by uneven mixing of raw materials. The reasonable sampling operation of the partitioning method ensures the representativeness and reliability of the viscosity detection results, avoids parameter judgment errors caused by improper sampling, and can promptly detect colloid stratification problems, laying a solid foundation for subsequent optimization of stirring parameters and improvement of the uniformity of the target basic colloid.

[0101] Specifically, the process of determining the difference in the actual Brinell viscosity of the zones includes:

[0102] Based on the comparison between the actual Brinell viscosity of the upper partition and the actual Brinell viscosity of the lower partition, the difference in the actual Brinell viscosity of the partition is determined.

[0103] Please see Figure 3 As shown, it is a flowchart of the process for determining the stirring parameters of the reactor stirring device in this embodiment;

[0104] Specifically, the process of determining the stirring parameters of the reactor stirring device includes:

[0105] Based on the difference being less than or equal to the difference threshold, the agitation parameters are not adjusted;

[0106] Based on the fact that the difference is greater than the difference threshold, the stirring parameters are adjusted according to the comparison results between the actual Brinell viscosity of the upper zone and the actual Brinell viscosity of the lower zone.

[0107] Specifically, the process of adjusting the stirring parameters based on the comparison between the actual Brinell viscosity of the upper zone and the actual Brinell viscosity of the lower zone includes:

[0108] Based on the fact that the actual Brinell viscosity of the upper zone is less than that of the lower zone, the stirring speed of the stirring device at the top of the reactor is increased according to the difference between the actual Brinell viscosity of the lower zone and the actual Brinell viscosity of the upper zone.

[0109] Based on the fact that the actual Brinell viscosity of the upper zone is greater than that of the lower zone, the blowing flow rate of the bottom gas distribution device at the bottom of the reactor is increased according to the difference between the actual Brinell viscosity of the upper zone and the actual Brinell viscosity of the lower zone.

[0110] In this embodiment of the invention, the difference threshold, i.e., the partitioned Brookfield viscosity difference threshold, is set to 500 mPa. Based on the Brinell viscosity of the upper and lower colloidal regions, the difference threshold is determined to be 4800-4200=600mPa. s;

[0111] If the difference is less than or equal to the difference threshold, the stirring parameters will not be adjusted.

[0112] If the difference is greater than the difference threshold, the stirring parameters are adjusted based on the comparison between the actual Brinell viscosity of the upper zone and the actual Brinell viscosity of the lower zone.

[0113] Based on the fact that the actual Brinell viscosity of the upper zone is less than that of the lower zone, the stirring speed of the stirring device at the top of the reactor is increased according to the difference between the actual Brinell viscosity of the lower zone and the actual Brinell viscosity of the upper zone.

[0114] The partition difference is 600 mPa. s, exceeding the threshold of 100mPa In this embodiment of the invention, the stirring speed adjustment coefficient of the upper stirring device is set to 0.5 r / min. (mPa s), that is, every 1 mPa exceeding the threshold If the upper stirring speed is increased by 0.5 r / min, the required increase in stirring speed is (600 mPa). s-500mPa s)×0.5r / min mPa s=50r / min, the initial stirring speed of the upper stirring device of the reactor is 450r / min, and the speed after adjustment is 450r / min+50r / min=500r / min;

[0115] If the actual Brinell viscosity of the upper region is 4800 mPa The actual Brinell viscosity of the lower partition is 4200 mPa. If s, then the partition difference = 4800mPa s-4200mPa s=600mPa s > 500 mPa s, the stirring parameters need to be adjusted;

[0116] The comparison results show that the actual Brookfield viscosity of the upper zone is greater than that of the lower zone, meaning the initial basic colloidal viscosity of the upper zone is higher. Therefore, the air flow rate of the bottom gas distribution device in the reactor needs to be increased. In this embodiment of the invention, the initial air flow rate of the bottom gas distribution device is set to 0.2 m³ / s. 3 / h, every 1mPa exceeding the threshold s, the blowing flow rate increased by 0.001m 3 If the airflow rate is adjusted to 0.2 m³ / h, then the adjusted airflow rate will be 0.2 m³ / h. 3 / h+(600-500)×0.001m 3 / h=0.3m 3 / h.

[0117] By scientifically calculating the difference in actual Brinell viscosity between zones and combining it with preset thresholds to accurately determine the adjustment requirements of stirring parameters, on-demand control of stirring parameters is achieved, avoiding energy waste and process instability caused by blind adjustment. Based on the viscosity comparison results of the upper and lower zones, different adjustment methods are adopted to efficiently solve the problem of colloid stratification, accurately improve colloid uniformity, effectively enhance the mixing quality of the target base colloid, and avoid problems such as abnormal subsequent preparation processes and substandard product performance caused by colloid stratification.

[0118] Specifically, the process of adjusting the stirring parameters based on the comparison between the actual Brinell viscosity of the upper zone and the actual Brinell viscosity of the lower zone also includes:

[0119] Based on the maximum stirring speed of the stirring device, the blowing pressure of the bottom air distribution device is increased according to the difference between the actual Brinell viscosity of the lower zone and the actual Brinell viscosity of the upper zone.

[0120] Based on the maximum blowing flow rate achieved by the bottom air distribution device, the stirring angle of the stirring device blades is increased according to the difference between the actual Brinell viscosity of the upper zone and the actual Brinell viscosity of the lower zone.

[0121] Wherein, the blade stirring angle is the angle between the stirring blade and the horizontal plane.

[0122] In this embodiment of the invention, the maximum stirring speed of the upper stirring device is set to 500 r / min, meaning that the initial basic colloid cannot be effectively stirred after reaching this speed, and the maximum air flow rate of the bottom air distribution device is 0.5 m³ / min. 3 / h, meaning that once this flow rate is reached, effective initial basic colloid mixing is no longer possible. The initial stirring angle of the stirring blades is set to 30°, where the angle between the stirring blades and the horizontal plane ranges from 0° to 60°. The larger the angle, the stronger the axial stirring force, which is more conducive to the convection mixing of the upper and lower colloids. The initial blowing pressure of the bottom air distribution device is 0.1MPa, and the maximum blowing pressure is 0.3MPa. In this embodiment of the invention, the pressure adjustment coefficient is set to 0.001MPa / mPa. s means that for every 1 mPa exceeding the difference threshold s, blowing pressure increased by 0.001 MPa; tilt angle adjustment coefficient 0.1° / mPa s means that for every 1 mPa exceeding the difference threshold s, the blade tilt angle increases by 0.1°;

[0123] Scenario 1: The stirring device reaches its maximum stirring speed. The air pressure of the bottom air distribution device is increased, and the upper stirring speed is adjusted to the maximum of 500 r / min. The actual Brinell viscosity of the upper and lower sections is measured again, and the difference is 550 mPa. s still > 500 mPa Since the actual Brinell viscosity of the upper zone is less than that of the lower zone, further adjustment by increasing the speed is not possible. Based on the difference, the required increase in blowing pressure is determined according to the pressure adjustment coefficient: (550-500)×0.001MPa / mPa. s=0.05MPa, the initial blowing pressure of the bottom air distribution device is 0.1MPa, and the adjusted blowing pressure is 0.1MPa + 0.05MPa = 0.15MPa;

[0124] Scenario 2: The bottom air distribution device reaches its maximum airflow rate. Increasing the blade angle of the agitator reduces the bottom airflow rate from the initial 0.2 m³ / h. 3 / h adjusted to the maximum of 0.5m 3 After reaching the maximum blowing flow rate, the actual Brinell viscosity of the upper and lower sections was measured again, and the difference was 580 mPa. s, and the actual Brinell viscosity of the upper zone is greater than that of the lower zone. In this embodiment of the invention, the blade stirring angle is the angle between the stirring blade and the horizontal plane. The initial angle is 30°. Increasing the angle can enhance the axial pushing force of the stirring blade on the colloid, promoting the downward flow of the high-viscosity colloid in the upper part and its mixing with the low-viscosity colloid in the lower part. Based on the viscosity difference of 580 mPa... s, the required increase in blade stirring angle is determined according to the tilt angle adjustment coefficient = (580-500)×0.1° / mPa s=8°, adjust the tilt angle = 30°+8°=38°.

[0125] For situations where the stirring device reaches its performance limit, a progressive stirring parameter adjustment scheme is provided, which makes up for the limitations of a single adjustment method and realizes comprehensive and in-depth control of colloid uniformity. By adjusting the blowing pressure of the bottom gas distribution device or the stirring angle of the stirring device blades according to the viscosity difference between the upper and lower zones, the problem of colloid stratification can be effectively solved when the stirring speed or gas distribution flow rate reaches the maximum value and cannot be adjusted further. This ensures that the uniformity of the target base colloid meets the standard, avoids the process bottleneck caused by a single adjustment method, and improves the flexibility and adaptability of the preparation process.

[0126] Specifically, the process of adjusting the amount of composite regeneration and repair agent added includes:

[0127] Based on the fact that the asphaltene content of the masterbatch is less than the minimum value of the threshold range of masterbatch asphaltene content, the amount of composite regeneration and repair agent added is increased according to the difference between the minimum value of the threshold range of masterbatch asphaltene content and the masterbatch asphaltene content.

[0128] Based on the fact that the asphaltene content of the masterbatch is within the threshold range of the masterbatch asphaltene content, the current amount of composite regeneration and repair agent is maintained;

[0129] Based on the fact that the asphaltene content of the masterbatch is greater than the maximum value of the threshold range of masterbatch asphaltene content, the amount of composite regeneration and repair agent added is reduced according to the difference between the masterbatch asphaltene content and the maximum value of the threshold range of masterbatch asphaltene content.

[0130] In this embodiment of the invention, the composite regeneration and repair agent includes waste rubber powder and vegetable oleic acid in a mixing ratio of 3:1. After the viscosity difference between the upper and lower sections of the reactor reaches the standard and the initial base colloid is uniform, 102.3g of recycled waste asphalt with an asphalt content of 12.36% is added to the base colloid and mixed to form a base recycled asphalt masterbatch. The asphalt content of the base recycled asphalt masterbatch is detected, and the amount of composite regeneration and repair agent added is adjusted according to the relationship between the asphalt content of the masterbatch and the preset threshold range of the asphalt content of the masterbatch.

[0131] In this embodiment of the invention, the threshold range of asphalt content in the masterbatch is set to 13.0%-15.0%, and the adjustment coefficient of the composite regeneration repair agent is 1.2. That is, for every 100g of basic recycled asphalt masterbatch, if the asphalt content deviates from the threshold range of masterbatch asphalt content by 1%, 1.2g of composite regeneration repair agent needs to be adjusted.

[0132] The asphalt content of the base recycled asphalt masterbatch was found to be 12.5%, which is less than the minimum value of the asphalt content threshold range. Based on the difference between the minimum value of the asphalt content threshold range and the asphalt content, the amount of composite regeneration repair agent added was increased. The required amount of composite regeneration repair agent added was determined as follows: total mass of masterbatch × (difference between the asphalt content of masterbatch and the maximum value of the asphalt content threshold range / 100) × adjustment coefficient, i.e., 80.1023kg × (0.5% / 100%) × 1.2g / 100g × 1000 ≈ 4806g. We took 4.81kg, where 1000 is used to convert kg to g. An additional 4.81kg of composite regeneration repair agent was added to the reactor.

[0133] If the asphalt content of the base recycled asphalt masterbatch is 15.8%, the amount of composite recycling repair agent added should be reduced based on the difference between the asphalt content and the maximum value of the threshold range. The amount of composite recycling repair agent to be reduced is 80.1023kg × (0.8% / 100%) × 1.2g / 100g × 1000 ≈ 7689g, which is 7.69kg. The original planned amount of composite recycling repair agent should be reduced by 7.69kg to ensure that the hardness of the base recycled asphalt masterbatch is moderate and to avoid low-temperature cracking due to excessive asphalt content.

[0134] By detecting the actual asphaltene content of the base recycled asphalt masterbatch and combining it with preset threshold ranges and content differences, targeted adjustments to the dosage of the repair agent can be made to effectively control the asphaltene content of the masterbatch within a reasonable range. This avoids unsuitable hardness and performance damage caused by abnormal asphaltene content. This process standardizes the adjustment logic of the repair agent dosage and clarifies the adjustment basis. It fully leverages the regeneration and repair function of the composite recycled repair agent while avoiding waste or insufficient dosage of the repair agent, ensuring that the final recycled asphalt masterbatch meets road performance standards, and improving the recycling rate of waste asphalt.

[0135] Specifically, the process of determining the amount of compatibilizer to be added includes:

[0136] The actual Brinell viscosity of the base recycled asphalt masterbatch after adjusting the amount of composite recycling repair agent is detected, and the adjusted actual Brinell viscosity is obtained. The amount of compatibilizer added is determined by comparing the adjusted actual Brinell viscosity with the preset Brinell viscosity threshold range of recycled asphalt masterbatch.

[0137] Based on the fact that the adjusted actual Brinell viscosity is less than the minimum value of the Brinell viscosity threshold range, the amount of compatibilizer added is reduced according to the difference between the adjusted actual Brinell viscosity and the minimum value of the Brinell viscosity threshold range.

[0138] Based on the fact that the adjusted actual Brinell viscosity is within the Brinell viscosity threshold range, the current compatibilizer addition amount is maintained;

[0139] Based on the fact that the adjusted actual Brinell viscosity is greater than the maximum value of the Brinell viscosity threshold range, the amount of compatibilizer added is increased according to the difference between the adjusted actual Brinell viscosity and the maximum value of the Brinell viscosity threshold range.

[0140] In this embodiment of the invention, the actual Brinell viscosity of the adjusted base recycled asphalt masterbatch at 150°C is used as a basis, and compared with its corresponding preset Brinell viscosity threshold range. By increasing, decreasing and maintaining the amount of compatibilizer added, the viscosity of the masterbatch is finally locked within the range that is operable in construction.

[0141] In this embodiment of the invention, the compatibilizer includes maleic anhydride-grafted polyethylene, and the Brookfield viscosity threshold range of the recycled asphalt masterbatch is set to 3000-3500 mPa. The amount of compatibilizer added is determined based on the pumping and mixing requirements of road construction, and the adjustment coefficient is set at 0.5 kg / 100 mPa. s, that is, every 100 mPa deviation from the boundary of the Brinell viscosity threshold range of recycled asphalt masterbatch. For every ton of basic recycled asphalt masterbatch, 0.5 kg of compatibilizer needs to be added. The role of the compatibilizer is to reduce viscosity and improve compatibility.

[0142] The testing conditions were as follows: a Brookfield viscometer was used, and the testing temperature was 150±0.1℃.

[0143] Samples were taken from the base recycled asphalt masterbatch after adjusting the amount of composite recycling remediation agent added, and its actual Brinell viscosity was tested at 150℃. The adjusted actual Brinell viscosity was 3650 mPa. s;

[0144] Based on the fact that the adjusted actual Brinell viscosity is greater than the maximum value of the Brinell viscosity threshold range, the amount of compatibilizer added is increased according to the difference between the adjusted actual Brinell viscosity and the maximum value of the Brinell viscosity threshold range. 3650-3500=150mPa The required increase in compatibility dose is 150 mPa. s / 100mPa s×0.5kg / t×84.91kg≈0.064kg,

[0145] After adding 64g of compatibilizer to the reactor and stirring for 5 minutes, the viscosity of the masterbatch decreased to 3480mPa. s;

[0146] If the adjusted actual Brinell viscosity is detected to be 3280 mPa s;

[0147] Based on the fact that the adjusted actual Brinell viscosity is within the Brinell viscosity threshold range, the current compatibilizer addition amount is maintained;

[0148] Maintain the current amount of compatibilizer added, i.e., do not add any additional compatibilizer. If the formulation contains a basic compatibilizer, keep it unchanged.

[0149] Based on the fact that the adjusted actual Brinell viscosity is less than the minimum value of the Brinell viscosity threshold range, the amount of compatibilizer added is reduced according to the difference between the adjusted actual Brinell viscosity and the minimum value of the Brinell viscosity threshold range.

[0150] If the adjusted actual Brinell viscosity is detected to be 2850 mPa The difference between the adjusted actual Brinell viscosity and the minimum value of the Brinell viscosity threshold range is 3000 - 2850 = 150 mPa. The required reduction in compatible dose is 150 mPa. s / 100mPa s×0.5kg×84.91 / 1000≈0.064kg, take 64g, but only 36g was actually added.

[0151] By testing and adjusting the Brookfield viscosity of the masterbatch, and combining it with the preset threshold range and viscosity difference, targeted operations such as increasing, decreasing, or maintaining the amount of compatibilizer can be taken to effectively control the masterbatch viscosity within the construction compatibility range, avoid construction problems caused by abnormal viscosity, fully utilize the effect of compatibilizer in reducing viscosity and improving compatibility, and avoid resource waste or masterbatch performance defects caused by improper use of compatibilizer.

[0152] Specifically, the process of determining the amount of composite anti-aging agent to be added includes:

[0153] The penetration at 25°C of the base recycled asphalt masterbatch is tested to obtain the actual penetration, and the actual penetration is compared with the preset penetration threshold range.

[0154] Based on the fact that the actual penetration is less than the minimum value of the penetration threshold range, the amount of compound anti-aging agent added is increased according to the difference between the minimum value of the penetration threshold range and the actual penetration.

[0155] Based on the actual penetration being within the penetration threshold range, maintain the current amount of compound anti-aging agent added.

[0156] Based on the fact that the actual penetration is greater than the maximum value of the penetration threshold range, the amount of compound anti-aging agent added is reduced according to the difference between the actual penetration and the maximum value of the penetration threshold range.

[0157] In this embodiment, the hardness of asphalt is reflected by detecting the penetration at 25°C, and the amount of composite anti-aging agent added is dynamically adjusted.

[0158] The penetration test is performed at a temperature of 25℃, a load of 100g, and a duration of 5s. The depth of the standard needle vertically penetrating into the base recycled asphalt masterbatch is measured. The result is expressed as 0.1mm as 1dmm. The 100g load refers to the total vertical mass of the standard needle assembly acting on the base recycled asphalt masterbatch.

[0159] In this embodiment of the invention, the composite anti-aging agent includes butylated hydroxytoluene and vitamin E in a ratio of 2:1. The penetration threshold range is set to 40-60 dmm, which is determined according to the road application requirements of recycled asphalt masterbatch. The anti-aging agent adjustment coefficient is set to 0.8 kg / 10 dmm. For each ton of basic recycled asphalt masterbatch, that is, for every 10 penetration units deviating from the penetration threshold range boundary, 0.8 kg of composite anti-aging agent needs to be adjusted for each ton of masterbatch recycled asphalt masterbatch. After adjusting the compatibilizer, the basic recycled asphalt masterbatch is sampled, cooled to room temperature, and its 25℃ penetration is tested according to the above method. The actual penetration is 66 dmm.

[0160] The actual penetration is less than the minimum value of the penetration threshold range. Based on the difference between the minimum value of the penetration threshold range and the actual penetration, the amount of composite anti-aging agent added is increased. An actual penetration of 66 dmm indicates that the asphalt is too soft and has insufficient high-temperature stability. The addition of composite anti-aging agent can inhibit asphalt aging. At the same time, its own characteristics will increase the hardness of asphalt. Therefore, it is necessary to increase the amount added to enhance the anti-aging performance and reduce the penetration to the qualified range. The amount of composite anti-aging agent added needs to be increased by 6 / 10×0.8kg / t×85.0 / 1000t≈0.0408kg, take 41g, and add an extra 41g of composite anti-aging agent to the original basic formula. Stir evenly at 150℃.

[0161] The actual penetration is within the penetration threshold range, so the current amount of compound anti-aging agent is maintained.

[0162] If the actual penetration is greater than the maximum value of the penetration threshold range, the amount of composite anti-aging agent added should be reduced based on the difference between the actual penetration and the maximum value of the penetration threshold range. If the actual penetration is measured to be 35 dmm, this indicates that the base recycled asphalt masterbatch is too hard. Although it has good high-temperature performance, it is prone to brittleness at low temperatures. Adding a large amount of anti-aging agent would make the asphalt even harder, so the amount added needs to be reduced. The amount of composite anti-aging agent to be reduced is approximately 5 / 10 × 0.8 kg / t × 85.0 / 1000t ≈ 0.034 kg, or 34 g. If the original plan was to add 500 g of composite anti-aging agent, then only 500 g will actually be added. This ensures that the base recycled asphalt masterbatch has sufficient low-temperature flexibility.

[0163] By standardizing the testing of the masterbatch penetration and combining it with the preset threshold range and penetration difference, targeted adjustments or maintenance of the anti-aging agent dosage can be made to effectively control the hardness of the masterbatch and avoid road performance defects caused by the masterbatch being too soft or too hard. This fully utilizes the anti-aging agent's effect of inhibiting asphalt aging while avoiding performance imbalances and resource waste caused by improper dosage of the anti-aging agent.

[0164] This embodiment also provides a stirring device inside a reaction vessel, including:

[0165] A stirring device is installed on the upper part of the reaction vessel, including a rotating rod and stirring blades. The stirring blades are mounted on the rotating rod and the stirring angle of the blades can be adjusted.

[0166] The bottom gas distribution device is located at the bottom of the reactor and includes several gas distribution pipes, which are arranged opposite to the stirring device.

[0167] The technical solution of the present invention has been described above with reference to the preferred embodiments shown in the accompanying drawings. However, it will be readily understood by those skilled in the art that the scope of protection of the present invention is obviously not limited to these specific embodiments. Without departing from the principles of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will all fall within the scope of protection of the present invention.

[0168] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for preparing a masterbatch of reclaimed asphalt based on RAP, characterized in that, include: The waste asphalt mixture is crushed and dried to obtain a dry waste asphalt mixture. The dry waste asphalt mixture is then centrifuged and extracted to obtain waste aggregate and waste asphalt. The asphalt content in waste asphalt is detected to obtain the actual asphalt content. The actual asphalt content is compared with the asphalt content threshold range to determine whether the waste asphalt mixture meets the requirements for the preparation of recycled asphalt masterbatch. Based on the mixing of hard asphalt masterbatch and target asphalt in the reactor, an initial base colloid is obtained. The Brinell viscosity of the base colloid at 150°C is measured to obtain the actual Brinell viscosity of the zone. The actual Brinell viscosity of the upper zone is compared with that of the lower zone to determine the difference between the actual Brinell viscosity of the zones. Based on the comparison result between the difference and the difference threshold, the stirring parameters of the reactor stirring device are determined. The target base colloid is obtained by stirring based on the determined stirring parameters; The composite regeneration and repair agent is added to the target base colloid and heated and stirred to obtain the base recycled asphalt masterbatch. The asphalt content of the masterbatch is tested to adjust the amount of composite regeneration and repair agent added. The amount of compatibilizer added is determined based on the adjusted actual Brinell viscosity, and the amount of composite anti-aging agent added is determined based on the penetration of the base recycled asphalt masterbatch, so as to obtain the target recycled asphalt masterbatch. The 150℃ Brookfield viscosity refers to the fluid viscosity value of the base colloid measured by a Brookfield viscometer under test conditions at 150℃. The stirring parameters include air flow rate, air pressure, stirring speed, and blade stirring angle.

2. The method for preparing a masterbatch of reclaimed asphalt based on RAP according to claim 1, characterized in that, The process for determining whether waste asphalt mixtures meet the requirements for preparing recycled asphalt masterbatch includes: Based on the fact that the actual asphalt content is less than the minimum value of the asphalt content threshold range, the amount of waste asphalt mixture is increased according to the difference between the minimum value of the asphalt content threshold range and the actual asphalt content. Based on the actual asphalt content being within the asphalt content threshold range, the current amount of waste asphalt mixture will be maintained. Based on the fact that the actual asphalt content is greater than the maximum value of the asphalt content threshold range, the amount of waste asphalt mixture is reduced according to the difference between the actual asphalt content and the maximum value of the asphalt content threshold range.

3. The method for preparing a masterbatch of reclaimed asphalt based on RAP according to claim 2, characterized in that, The process of obtaining the actual Brinell viscosity of the partition includes: The initial basic colloid in the reactor is divided into upper and lower basic colloid regions. The actual Brinell viscosity of the upper and lower basic colloid regions is detected to obtain the actual Brinell viscosity of each region.

4. The method for preparing a masterbatch of reclaimed asphalt based on RAP according to claim 3, characterized in that, The process of determining the difference in actual Brinell viscosity between zones includes: Based on the comparison between the actual Brinell viscosity of the upper partition and the actual Brinell viscosity of the lower partition, the difference in the actual Brinell viscosity of the partition is determined.

5. The method for preparing a masterbatch of reclaimed asphalt based on RAP according to claim 4, characterized in that, The process of determining the stirring parameters of the reactor stirring device includes: Based on the difference being less than or equal to the difference threshold, the agitation parameters are not adjusted; Based on the fact that the difference is greater than the difference threshold, the stirring parameters are adjusted according to the comparison results between the actual Brinell viscosity of the upper zone and the actual Brinell viscosity of the lower zone.

6. The method for preparing a masterbatch of reclaimed asphalt based on RAP according to claim 5, characterized in that, The process of adjusting the stirring parameters based on the comparison between the actual Brinell viscosity of the upper zone and the actual Brinell viscosity of the lower zone includes: Based on the fact that the actual Brinell viscosity of the upper zone is less than that of the lower zone, the stirring speed of the stirring device at the top of the reactor is increased according to the difference between the actual Brinell viscosity of the lower zone and the actual Brinell viscosity of the upper zone. Based on the fact that the actual Brinell viscosity of the upper zone is greater than that of the lower zone, the blowing flow rate of the bottom gas distribution device at the bottom of the reactor is increased according to the difference between the actual Brinell viscosity of the upper zone and the actual Brinell viscosity of the lower zone.

7. The method for preparing a masterbatch of reclaimed asphalt based on RAP according to claim 6, characterized in that, The process of adjusting the stirring parameters based on the comparison between the actual Brinell viscosity of the upper zone and the actual Brinell viscosity of the lower zone also includes: Based on the maximum stirring speed of the stirring device, the blowing pressure of the bottom air distribution device is increased according to the difference between the actual Brinell viscosity of the lower zone and the actual Brinell viscosity of the upper zone. Based on the maximum blowing flow rate achieved by the bottom air distribution device, the stirring angle of the stirring device blades is increased according to the difference between the actual Brinell viscosity of the upper zone and the actual Brinell viscosity of the lower zone. Wherein, the blade stirring angle is the angle between the stirring blade and the horizontal plane.

8. The method for preparing a masterbatch of reclaimed asphalt based on RAP according to claim 7, characterized in that, The process of adjusting the amount of compound regeneration and repair agent added includes: Based on the fact that the asphaltene content of the masterbatch is less than the minimum value of the threshold range of masterbatch asphaltene content, the amount of composite regeneration and repair agent added is increased according to the difference between the minimum value of the threshold range of masterbatch asphaltene content and the masterbatch asphaltene content. Based on the fact that the asphaltene content of the masterbatch is within the threshold range of the masterbatch asphaltene content, the current amount of composite regeneration and repair agent is maintained; Based on the fact that the asphaltene content of the masterbatch is greater than the maximum value of the threshold range of masterbatch asphaltene content, the amount of composite regeneration and repair agent added is reduced according to the difference between the masterbatch asphaltene content and the maximum value of the threshold range of masterbatch asphaltene content.

9. The method for preparing recycled asphalt masterbatch based on RAP blending according to claim 8, characterized in that, The process of determining the amount of compatibilizer to be added includes: The actual Brinell viscosity of the base recycled asphalt masterbatch after adjusting the amount of composite recycling repair agent is detected, and the adjusted actual Brinell viscosity is obtained. The amount of compatibilizer added is determined by comparing the adjusted actual Brinell viscosity with the preset Brinell viscosity threshold range of recycled asphalt masterbatch. Based on the fact that the adjusted actual Brinell viscosity is less than the minimum value of the Brinell viscosity threshold range, the amount of compatibilizer added is reduced according to the difference between the adjusted actual Brinell viscosity and the minimum value of the Brinell viscosity threshold range. Based on the fact that the adjusted actual Brinell viscosity is within the Brinell viscosity threshold range, the current compatibilizer addition amount is maintained; Based on the fact that the adjusted actual Brinell viscosity is greater than the maximum value of the Brinell viscosity threshold range, the amount of compatibilizer added is increased according to the difference between the adjusted actual Brinell viscosity and the maximum value of the Brinell viscosity threshold range.

10. The method for preparing recycled asphalt masterbatch based on RAP blending according to claim 9, characterized in that, The process of determining the amount of compound anti-aging agent to be added includes: The penetration at 25°C of the base recycled asphalt masterbatch is tested to obtain the actual penetration, and the actual penetration is compared with the preset penetration threshold range. Based on the fact that the actual penetration is less than the minimum value of the penetration threshold range, the amount of compound anti-aging agent added is increased according to the difference between the minimum value of the penetration threshold range and the actual penetration. Based on the actual penetration being within the penetration threshold range, maintain the current amount of compound anti-aging agent added. Based on the fact that the actual penetration is greater than the maximum value of the penetration threshold range, the amount of compound anti-aging agent added is reduced according to the difference between the actual penetration and the maximum value of the penetration threshold range.

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