Asphalt pavement mixture recycling device

Abstract

The utility model provides an asphalt pavement mixture recycling device which is characterized in that a regeneration drying roller comprises an inner barrel which is obliquely arranged, the inner barrel is coaxially sleeved with an outer barrel, and an interlayer is formed between the inner barrel and the outer barrel; the drying heat source is arranged on the feeding end side of the inner cylinder and is used for heating the primary aggregate in the inner cylinder through flame heat radiation and downstream high-temperature flue gas; the outer cylinder heats the recycled aggregate in the interlayer through heat conduction of the wall of the inner cylinder and countercurrent high-temperature flue gas, and the countercurrent high-temperature flue gas is high-temperature flue gas which overflows from the discharging end of the inner cylinder and then flows back into the interlayer from the discharging end of the outer cylinder; the storage assembly comprises a first heat preservation heating storage bin and a second heat preservation heating storage bin which are isolated from each other, the stirring pot is arranged at the bottom of the storage assembly, and the heated primary aggregate and the heated recycled aggregate are mixed in proportion and then are stirred with asphalt, a regenerant and powder in the stirring pot to obtain the asphalt pavement mixture. The device is smaller in occupied area, higher in integration and higher in heat efficiency.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of asphalt, in particular to a device for recycling and reusing asphalt pavement mixture. BACKGROUND

[0002] In the process of road construction and maintenance, the production and use of asphalt pavement mixture are crucial. The traditional production method of asphalt pavement mixture mainly relies on the use of a large amount of virgin aggregate. However, with the gradual scarcity of resources and the increasing environmental protection requirements, recycling and reusing waste asphalt pavement materials has become an important trend in the industry.

[0003] Currently, in the existing recycling and reusing technology of asphalt pavement mixture, the recycled aggregate and the virgin aggregate are usually placed in two independent drying cylinders for drying treatment. Each drying cylinder is equipped with a separate heat source. This design has many drawbacks. On the one hand, two drying cylinders need to occupy a large space, increasing the production cost and construction difficulty. On the other hand, using two independent heat sources for heating has low thermal efficiency and high energy consumption. Each heat source will produce a certain amount of heat loss during operation, resulting in serious energy waste. SUMMARY

[0004] In view of the above-mentioned defects or deficiencies in the prior art, the present application aims to provide a device for recycling and reusing asphalt pavement mixture to improve thermal efficiency. The device comprises:

[0005] A recycled drying roller, which comprises an inner cylinder arranged obliquely, an outer cylinder coaxially sleeved outside the inner cylinder, and a layer formed between the inner cylinder and the outer cylinder; the inlet end of the inner cylinder is higher than the outlet end of the inner cylinder, the inlet end of the inner cylinder is used to input virgin aggregate into the inner cylinder, and the inlet end of the outer cylinder is used to input recycled aggregate into the layer;

[0006] A drying heat source, which is arranged on the inlet end side of the inner cylinder and is used to heat the virgin aggregate in the inner cylinder through flame heat radiation and counter-flow high-temperature flue gas;

[0007] The outer cylinder heats the recycled aggregate in the layer through wall heat conduction of the inner cylinder and counter-flow high-temperature flue gas, and the counter-flow high-temperature flue gas is high-temperature flue gas that flows back into the layer from the outlet end of the outer cylinder after overflowing from the outlet end of the inner cylinder;

[0008] A storage assembly, which is arranged on the outlet end side of the inner cylinder and comprises a first heat preservation and heating storage bin and a second heat preservation and heating storage bin that are isolated from each other, the first heat preservation and heating storage bin is used to store heated recycled aggregate, and the second heat preservation and heating storage bin is used to store heated virgin aggregate;

[0009] A stirring pot is arranged at the bottom of the storage assembly. After being heated, the primary aggregate and the recycled aggregate are mixed in proportion, and then stirred with asphalt, a recycling agent and powder in the stirring pot to obtain asphalt pavement mixture.

[0010] According to the technical scheme provided in the embodiments of the present application, the inner wall of the inner cylinder is uniformly provided with a plurality of first blades. The first blades control the flow rate of the primary aggregate and the density of the heat exchange curtain by changing the blade angle, and cooperate with the flame size of the drying heat source to jointly adjust the temperature of the primary aggregate in the inner cylinder and / or the temperature of the recycled aggregate in the outer cylinder.

[0011] According to the technical scheme provided in the embodiments of the present application, a self-cleaning chain is arranged in the interlayer. The self-cleaning chain is in contact with the inner wall of the outer cylinder and rotates with the recycled drying drum to scrape off the recycled aggregate adhered to the inner wall of the outer cylinder. The water content of the recycled aggregate and the primary aggregate is less than 3%.

[0012] According to the technical scheme provided in the embodiments of the present application, the air induction mechanism includes an air induction port arranged at the outlet end of the outer cylinder. The air induction port is in communication with the interlayer, and the air induction port is connected with an air induction machine through an air induction pipeline to form negative pressure in the interlayer.

[0013] According to the technical scheme provided in the embodiments of the present application, the outlet end of the inner cylinder is in communication with a second heat preservation and heating storage bin, and the outlet end of the outer cylinder is in communication with a first heat preservation and heating storage bin. A metering scale is arranged directly below the first heat preservation and heating storage bin and the second heat preservation and heating storage bin. The metering scale is used to measure the heated recycled aggregate in the first heat preservation and heating storage bin and the heated primary aggregate in the second heat preservation and heating storage bin in proportion, and then convey them to the stirring pot.

[0014] According to the technical scheme provided in the embodiments of the present application, the inlet end of the inner cylinder is provided with a plurality of primary aggregate bins. Each of the primary aggregate bins contains different specifications of primary aggregate. The outlet end of each of the primary aggregate bins is provided with a corresponding first belt scale. The inlet end of the outer cylinder is provided with a plurality of recycled aggregate bins. The outlet end of each of the recycled aggregate bins is provided with a corresponding second belt scale. Different specifications of primary aggregate are layered and added into the inner cylinder through the corresponding first belt scale according to the proportioning requirement and in a preset time sequence. Different specifications of recycled aggregate are layered and added into the outer cylinder through the corresponding second belt scale according to the proportioning requirement and in a preset time sequence.

[0015] According to the technical scheme provided in the embodiments of the present application, the drying heat source is arranged at the inlet end of the inner cylinder. The direction of the generated flame is consistent with the inclination direction of the inner cylinder. The generated high-temperature flue gas sequentially flows through the inner cylinder, enters the outlet end of the outer cylinder from the outlet end of the inner cylinder, and then countercurrently flows in the interlayer.

[0016] According to the technical scheme provided by the embodiment of the application, the outer wall of the outer cylinder is attached with a heat preservation layer, and the inner wall of the outer cylinder is provided with a plurality of second blades which are uniformly distributed.

[0017] According to the technical scheme provided by the embodiment of the application, the inlet of the mixing pot is provided with a regenerating agent adding mechanism and an asphalt conveying mechanism, the asphalt conveying mechanism comprises an asphalt scale and a foaming mechanism, and the asphalt is injected into the mixing pot in a foamed or non-foamed state.

[0018] According to the technical scheme provided by the embodiment of the application, the inclination angle of the inner cylinder is 3-5 degrees, the radial cross-sectional area of the inner cylinder is the same as that of the interlayer, and the radial height of the interlayer is calculated according to the air flow rate required by the process.

[0019] Compared with the prior art, the device has the beneficial effects that: the device adopts a regenerating drying roller, and the inner cylinder and the outer cylinder are coaxially sleeved, so that the virgin aggregate and the recycled aggregate can be heated and dried in the same device. Compared with the traditional two independent drying cylinders, the integrated design greatly reduces the floor area of the equipment, reduces the requirement for site space, is especially suitable for areas with limited land resources, and effectively saves production cost and construction cost. The virgin aggregate in the inner cylinder is heated by flame heat radiation and downflow high-temperature flue gas, and the recycled aggregate in the interlayer is heated by the wall heat conduction of the inner cylinder and the upflow high-temperature flue gas. This design realizes the step-by-step utilization of heat, the high-temperature flue gas overflowing from the discharge end of the inner cylinder is utilized again, and the recycled aggregate is heated in the interlayer in an upflow manner, so that the waste heat in the flue gas is fully utilized, and the waste of heat is avoided. Compared with the traditional two independent heat source heating mode, the heat efficiency is significantly improved, the energy consumption is reduced, and the development concept of energy saving and environmental protection is met. Under this unique heating mode, the virgin aggregate and the recycled aggregate can be heated in suitable environments respectively. The high-temperature environment of the inner cylinder is conducive to rapidly and uniformly heating the virgin aggregate, so that the virgin aggregate reaches a suitable construction temperature; and the relatively mild heating mode in the interlayer avoids excessive aging and performance loss of the old asphalt in the recycled aggregate, so that the quality of the recycled aggregate is ensured. After being heated, the two kinds of aggregates are respectively stored in the first heat preservation and heating storage bin and the second heat preservation and heating storage bin, so that the quality stability of the aggregates is further ensured, and a strong guarantee is provided for subsequent mixing of high-quality asphalt pavement mixture. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 The structure schematic view of the asphalt pavement mixture recycling and regenerating utilization device provided by the embodiment of the application is shown in the figure.

[0021] Figure 2 The structure schematic view of the self-cleaning chain provided by the embodiment of the application is shown in the figure.

[0022] Figure 3 A structural schematic diagram of the first and second blades provided for the embodiment of the present application is shown in the figure;

[0023] Figure 4 A structural schematic diagram of the hopper and leaf pulp provided for the embodiment of the present application is shown in the figure.

[0024] The text annotations in the figure represent:

[0025] 1, recycled aggregate bin; 2, virgin aggregate bin; 3, drying heat source; 4, recycled drying drum; 41, inner cylinder; 42, outer cylinder; 43, interlayer; 5, first heat preservation and heating storage bin; 6, second heat preservation and heating storage bin; 7, metering scale; 8, asphalt conveying mechanism; 9, powder scale; 10, mixing pot; 11, smoke box; 12, dust collector; 13, chimney; 14, rake; 15, self-cleaning chain; 16, second blade; 17, first blade; 18, hopper; 19, leaf pulp. DETAILED DESCRIPTION

[0026] The present application will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely intended to explain the related application, and not to limit the application. In addition, it should be noted that only the parts related to the application are shown in the drawings for ease of description.

[0027] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict. The present application will be described in detail below with reference to the accompanying drawings and embodiments.

[0028] Embodiment 1

[0029] As mentioned in the background, in view of the problems in the prior art, the present application proposes an asphalt pavement mixture recycling and regenerating device, as shown in Figure 1 which comprises:

[0030] The recycled drying drum 4 comprises an inner cylinder 41 arranged obliquely, an outer cylinder 42 coaxially sleeved outside the inner cylinder 41, and an interlayer 43 formed between the inner cylinder 41 and the outer cylinder 42; the inlet end of the inner cylinder 41 is higher than the outlet end of the inner cylinder 41, the inlet end of the inner cylinder 41 is used to input virgin aggregate into the inner cylinder 41, and the inlet end of the outer cylinder 42 is used to input recycled aggregate into the interlayer 43.

[0031] Further, the inclination angle of the inner cylinder 41 is 3-5 degrees, the radial cross-sectional area of the inner cylinder 41 is the same as the radial cross-sectional area of the interlayer 43, and the radial height of the interlayer 43 is calculated according to the air flow rate required by the process.

[0032] Specifically, the native aggregate refers to the aggregate obtained through a series of processing processes such as mining, crushing, and screening from natural rocks or pebbles and the like resources. The recycled aggregate refers to the aggregate obtained through recycling, crushing, and screening of waste asphalt pavement materials, which is a mixture of coarse aggregate and fine aggregate and is derived from waste asphalt mixture generated in the renovation, reconstruction, or abandoned project of old asphalt pavement. The inclination angles of the inner cylinder 41 and the outer cylinder 42 are the same, and the inclination design that the inlet end is higher than the outlet end facilitates the movement of the aggregate from the inlet end to the outlet end by relying on its own gravity. The inlet end of the inner cylinder 41 is equipped with a feeding device (such as a belt conveyor) for inputting the native aggregate into the inner cylinder 41. The inlet end of the outer cylinder 42 is also provided with a feeding device for inputting the recycled aggregate into the interlayer 43. The native aggregate in the inner cylinder 41 is heated to about 230 degrees by the heat radiation of the flame and the countercurrent high-temperature hot air according to the proportioning and metering. The recycled aggregate in the outer cylinder 42 is heated to about 120 degrees by the heat radiation and heat conduction of the high-temperature hot flue gas through the wall of the inner cylinder 41 according to the proportioning and metering.

[0033] Specifically, the air flow rate required by the process is generally 4.7 m / s, and adaptively, the radial height of the interlayer is generally about 500 mm.

[0034] The drying heat source 3 is arranged at the inlet end side of the inner cylinder 41 for heating the native aggregate in the inner cylinder 41 by flame heat radiation and countercurrent high-temperature flue gas.

[0035] Further, the drying heat source 3 is arranged at the inlet end of the inner cylinder 41, and the direction of the generated flame is consistent with the inclination direction of the inner cylinder 41. The generated high-temperature flue gas flows in sequence through the inner cylinder 41, enters the outlet end of the outer cylinder 42 from the outlet end of the inner cylinder 41, and then flows countercurrently in the interlayer 43.

[0036] Specifically, a plurality of boxes 18 are arranged on the inner wall of the inner cylinder 41 for reducing the excessive heating of the inner wall of the inner cylinder 41 by the flame and playing a heat insulation role. When the drum rotates, the boxes 18 are full of aggregate. The drying heat source 3 is a burner installed at the inlet end side, which generates flame and high-temperature flue gas by burning fuel. The flame directly heats the native aggregate in the inner cylinder 41 by heat radiation, and the countercurrent high-temperature flue gas flows along the inclination direction of the inner cylinder 41 to further heat the native aggregate.

[0037] The outer cylinder 42 heats the recycled aggregate in the interlayer 43 by heat conduction through the wall of the inner cylinder 41 and countercurrent high-temperature flue gas. The countercurrent high-temperature flue gas is the high-temperature flue gas that flows countercurrently in the interlayer 43 after overflowing from the outlet end of the inner cylinder 41;

[0038] Specifically, the recycled aggregates in the interlayer 43 are heated mainly by two ways. On the one hand, the inner cylinder 41 wall is heated, and the heat is transferred to the recycled aggregates in the interlayer 43 through heat conduction; on the other hand, the high-temperature flue gas overflowing from the discharge end of the inner cylinder 41 flows back into the interlayer 43 from the discharge end of the outer cylinder 42, forming countercurrent high-temperature flue gas to heat the recycled aggregates.

[0039] A storage assembly is arranged at the discharge end side of the inner cylinder 41, which includes a first heat-insulated and heated storage bin 5 and a second heat-insulated and heated storage bin 6 isolated from each other, the first heat-insulated and heated storage bin 5 is used for storing the heated recycled aggregates, and the second heat-insulated and heated storage bin 6 is used for storing the heated virgin aggregates;

[0040] Specifically, the first heat-insulated and heated storage bin 5 and the second heat-insulated and heated storage bin 6 maintain the temperature in the bins through heat-insulating and heating devices (such as heating coils). The upper part of the storage assembly is provided with a smoke box 11 with heat insulation, which is a sealed metal box. The smoke box 11 is connected with the discharge end of the inner cylinder 41 through a flue, and is also communicated with the discharge end of the outer cylinder 42 through a pipeline. The high-temperature flue gas overflowing from the discharge end of the inner cylinder 41 enters the smoke box 11, and due to the sealing effect of the smoke box 11, the flue gas flows back into the interlayer 43 through the communication pipeline with the discharge end of the outer cylinder 42 under the action of pressure difference.

[0041] A mixing pot 10 is arranged at the bottom of the storage assembly, and the mixed virgin aggregates and recycled aggregates are mixed with asphalt, recycling agent and powder in the mixing pot 10 to obtain asphalt pavement mixture.

[0042] Further, the discharge end of the inner cylinder 41 is communicated with the second heat-insulated and heated storage bin 6, the discharge end of the outer cylinder 42 is communicated with the first heat-insulated and heated storage bin 5, and a metering scale 7 is arranged directly below the first heat-insulated and heated storage bin 5 and the second heat-insulated and heated storage bin 6, which is used for metering the heated recycled aggregates in the first heat-insulated and heated storage bin 5 and the heated virgin aggregates in the second heat-insulated and heated storage bin 6 and then conveying them to the mixing pot 10 in proportion.

[0043] Further, a recycling agent adding mechanism and an asphalt conveying mechanism 8 are arranged at the inlet of the mixing pot 10, the asphalt conveying mechanism 8 includes an asphalt scale and a foaming mechanism, and the asphalt is injected into the mixing pot 10 in foamed or unfoamed state.

[0044] Specifically, when it is needed to deliver the heated virgin aggregate and the heated recycled aggregate to the mixing kettle 10, the metering scale 7 weighs the aggregate according to a preset proportion (which can be a recycled material addition proportion of 40%-60%), and then the aggregate is delivered to the mixing kettle 10 through a discharging device (such as a discharging valve). Above the mixing kettle 10, a powder scale 9 is also provided, and at the same time, asphalt, a recycling agent, and powder are also added to the mixing kettle 10. Through the stirring device (such as a stirring paddle) in the mixing kettle 10, the asphalt pavement mixture is finally obtained, and the temperature is controlled at 160-170 degrees.

[0045] The working principle is described as follows: the asphalt pavement mixture recycling and regenerating device provided by the application realizes synchronous drying of the original aggregate and the recycled aggregate through a regenerating drying roller 4 and an oven heat source 3, improves the thermal efficiency, and saves energy. The original aggregate is heated in the inner cylinder 41, and the recycled aggregate is heated in the outer cylinder 42. There are four considerations. First, based on the properties of the aggregate: the original aggregate is processed from natural rocks and other resources, and its surface is relatively clean without old asphalt and other impurities. The temperature in the inner cylinder 41 is relatively high and stable, and the high-temperature flue gas can directly and fully contact the original aggregate, which is beneficial to quickly and evenly increase the temperature of the original aggregate to the appropriate construction temperature, meeting the requirements of subsequent mixing with asphalt and other materials. The recycled aggregate is obtained by recycling and processing waste asphalt pavement materials, and the surface is attached with old asphalt. If the recycled aggregate is directly placed in a high-temperature environment for rapid heating, the old asphalt may be over-aged or even burned, affecting the performance and quality of the recycled aggregate. The recycled aggregate is placed in the interlayer 43, and heated by heat conduction of the inner cylinder 41 wall and countercurrent high-temperature flue gas. This heating method is relatively mild, which can slowly heat the recycled aggregate and reduce the aging and performance loss of the old asphalt. Second, improve the heating efficiency: during the convection heating, the flow direction of the high-temperature flue gas is consistent with the moving direction of the original aggregate. In the initial stage, the high-temperature flue gas contacts the low-temperature original aggregate, and the temperature difference between them is large, so the heat exchange speed is fast, which can quickly transfer heat to the original aggregate, speed up the heating speed of the original aggregate, and improve the heating efficiency. During the countercurrent heating process, the recycled aggregate contacts the flue gas with gradually decreasing temperature. The recycled aggregate enters the interlayer 43 at the end with lower temperature, and gradually contacts the flue gas with higher temperature as it moves. This way keeps a certain temperature difference between the recycled aggregate and the flue gas throughout the heating process, prolongs the heat exchange time, improves the heat exchange efficiency, and makes the recycled aggregate absorb more heat. Third, make full use of energy: the high-temperature flue gas generated by the burner in the inner cylinder 41 is first used to heat the original aggregate in the inner cylinder 41. At this time, the temperature of the flue gas is relatively high. After the flue gas flows out of the discharge end of the inner cylinder 41, its temperature is still relatively high. The part of the flue gas is reused to heat the recycled aggregate in the interlayer 43 in countercurrent, realizing the cascade utilization of heat, fully utilizing the waste heat in the flue gas, improving the energy utilization efficiency, and reducing energy consumption. By placing the recycled aggregate in the interlayer 43 and using the heat conduction of the inner cylinder 41 wall for heating, the inner cylinder 41 plays a certain heat preservation role, reducing the heat loss of the inner cylinder 41, and further improving the energy utilization efficiency. Fourth, ensure the quality of the aggregate: for the original aggregate, the convection heating method can heat it to the appropriate temperature in a short time, avoiding the performance changes of the aggregate caused by long-time high-temperature heating. The recycled aggregate uses countercurrent heating, which is relatively mild, effectively avoiding the problems of old asphalt aging and coking caused by overheating, and ensuring the quality of the recycled aggregate.

[0046] In a preferred embodiment, the inner wall of the inner cylinder 41 is uniformly provided with a plurality of first vanes 17, which control the flow rate of the raw aggregate and the density of the heat exchange curtain by changing the vane angle, in cooperation with the flame size of the drying heat source 3, to jointly regulate the temperature of the raw aggregate in the inner cylinder 41 and / or the temperature of the recycled aggregate in the outer cylinder 42.

[0047] Specifically, as shown in Figure 3 The first vane 17 is connected to the inner wall of the inner cylinder 41 through a special angle adjusting mechanism (such as an electric push rod or a hydraulic push rod), which can change the vane angle. When it is necessary to control the flow rate of the raw aggregate, the angle of the first vane 17 is changed through the adjusting mechanism. For example, the vane angle is adjusted to be smaller, the pushing effect of the vane on the raw aggregate is weakened, and the flow rate is slowed down; on the contrary, the vane angle is adjusted to be larger, and the flow rate of the raw aggregate is accelerated. The change of the vane angle also affects the density of the heat exchange curtain. A larger vane angle will make the raw aggregate more dispersedly distributed in the inner cylinder 41, forming a more dense heat exchange curtain; a smaller vane angle will make the raw aggregate relatively concentrated, and the density of the heat exchange curtain is reduced. Based on this, the first vane 17 and the drying heat source 3 together can realize temperature regulation: the heating temperature of the new aggregate and the recycled aggregate is controlled by controlling the flame size and the first vane 17, when the raw aggregate temperature and the recycled aggregate temperature are both suitable but the yield is low, the flame is increased. The raw aggregate temperature is suitable, the recycled aggregate temperature is low, the angle of the first vane 17 is adjusted to be larger, the flow rate of the raw aggregate is accelerated and the formation of the heat exchange curtain is reduced, the flame is increased to improve the flue gas temperature in the outer cylinder 42, which is generally about 300 degrees. When the raw aggregate temperature is low and the recycled aggregate temperature is suitable, the angle of the first vane 17 is adjusted to be smaller, the flow rate of the raw aggregate is slowed down and the formation of the heat exchange curtain is increased, and the flame is appropriately increased to improve the raw aggregate temperature and keep the recycled aggregate temperature suitable.

[0048] In a preferred embodiment, the interlayer 43 is provided with a self-cleaning chain 15, which is in contact with the inner wall of the outer cylinder 42 and rotates with the recycled drying drum 4 to scrape off the recycled aggregate adhering to the inner wall of the outer cylinder 42; the water content of the recycled aggregate and the raw aggregate is less than 3%.

[0049] Specifically, as shown in Figure 2As shown, the outer cylinder 42 inner wall is provided with a plurality of evenly distributed harrow 14, for the formation of the material curtain in the process of regenerative drying drum 4 rolling, from the cleaning chain 15 one end through the fixed device (such as hook or bolt) connected to the harrow 14, the other end is free, from the cleaning chain 15 free end can be in contact with the outer cylinder 42 inner wall, can be in contact with the inner cylinder 41 outer wall, also can be in contact with the harrow 14, when the regenerative drying drum 4 rotates, the cleaning chain 15 rotates with the drum, in the process of rotation, the cleaning chain 15 will be the harrow 14 inside and outside, inner cylinder 41 outer wall, outer cylinder 42 inner wall relative friction, can scrape off the adhering to the regenerative aggregate, prevent the regenerative aggregate on the wall of the accumulation of influence heating effect. To ensure the normal operation of the device and heating effect, the regenerative aggregate and the virgin aggregate need to be stored in the greenhouse before entering the device to prevent rain, using solar energy and green ventilation device, through the drying equipment (such as dryer) for pretreatment, so that their moisture content is less than 3%.

[0050] Further, as shown in the figure, Figure 4 The outer cylinder 42 inner wall is also provided with a leaf pulp 19, the regenerative aggregate in the sandwich 43 is heated in different areas, different sections adopt different anti bonding methods, for example, the discharge section because of high temperature (close to the discharge end of the cylinder section) adopts the harrow 14 plus the cleaning chain 15 to prevent bonding, the front end of the feeding because of low temperature is not easy to bond, which can be prevented by using the leaf pulp 19 method.

[0051] In a preferred embodiment, it also includes the air induction mechanism, the air induction mechanism includes the air induction port arranged in the outlet end of the outer cylinder 42, the air induction port communicates with the sandwich 43, the air induction port is connected with the air induction fan through the air induction pipeline, so that the negative pressure is formed in the sandwich 43.

[0052] Specifically, after the air induction fan is started, the air in the sandwich 43 is extracted through the air induction pipeline, at the same time, the feeding chute of the regenerative aggregate is provided with a one-way air locking device, so that the regenerative aggregate can enter the sandwich 43, but the air cannot enter, which together forms the negative pressure in the sandwich 43. This negative pressure environment is conducive to the smooth backflow of the high temperature flue gas overflowing from the discharge end of the inner cylinder 41 into the sandwich 43 from the discharge end of the outer cylinder 42, which enhances the heating effect of the regenerative aggregate, and also helps to discharge the dust and waste gas in the sandwich 43. The high temperature flue gas can only enter from the discharge end of the outer cylinder 42 along the sandwich 43, and then flow upward, and then be discharged from the inlet end of the sandwich 43, and then be discharged from the chimney 13 after entering the dust remover 12.

[0053] In a preferred embodiment, the inner cylinder 41 is provided with a plurality of primary aggregate bins 2 at the feeding end, each of which contains different specifications of primary aggregate, and the discharge end of each of the primary aggregate bins 2 is provided with a corresponding first belt scale, and the outer cylinder 42 is provided with a plurality of recycled aggregate bins 1 at the feeding end, and the discharge end of each of the recycled aggregate bins 1 is provided with a corresponding second belt scale; different specifications of primary aggregate are layered and stacked into the inner cylinder 41 through the corresponding first belt scale according to the mixing ratio requirement and at a preset time sequence, and different specifications of recycled aggregate are layered and stacked into the outer cylinder 42 through the corresponding second belt scale according to the mixing ratio requirement and at a preset time sequence.

[0054] Specifically, the inner cylinder 41 is provided with a plurality of independent bin primary aggregate bins 2 (such as 3-4), each of which stores primary aggregate of different particle size specifications (such as coarse aggregate, medium aggregate, and fine aggregate). Similarly, a plurality of independent bin recycled aggregate bins 1 are provided, each of which stores different particle size recycled aggregate (such as RAP-10, RAP-20, etc.) after crushing and screening. The discharge end of each primary aggregate bin 2 is provided with a corresponding first belt scale (high-precision electronic belt scale), and the discharging speed is dynamically adjusted according to the preset mixing ratio (such as coarse: medium: fine = 40%: 30%: 30%). The discharge end of each recycled aggregate bin 1 is also provided with a high-precision electronic belt scale (second belt scale), and the flow rate is controlled according to the recycled aggregate mixing ratio (such as RAP-10: RAP-20 = 60%: 40%).

[0055] Specifically, after the system is started, each bin belt scale is started at different times according to the process set feeding sequence (such as “coarse→medium→fine” or “recycled fine→recycled coarse”), so as to avoid excessive instantaneous load. For example, the coarse aggregate belt scale is started first, the medium aggregate belt scale is started after a delay of 2 seconds, and the fine aggregate belt scale is started after a further delay of 2 seconds. For recycled aggregate, fine recycled aggregate is fed first, and coarse recycled aggregate is fed after a delay of 3 seconds. Different specifications of aggregate are layered and stacked through the belt conveyor to form a “vertically layered and horizontally continuous” material belt. For example, the layers on the primary aggregate belt conveyor are coarse aggregate (bottom layer), medium aggregate (middle layer), and fine aggregate (upper layer) in sequence. The layers on the recycled aggregate belt conveyor are fine RAP (bottom layer) and coarse RAP (upper layer). The layered primary aggregate is fed into the inner cylinder (41) through the inclined chute, and the recycled aggregate is fed into the outer cylinder (42) through the independent chute. The purpose of layered and stacked feeding according to the time sequence is to ensure that the aggregate entering the drum has consistent mixing ratio.

[0056] In a preferred embodiment, the outer wall of the outer cylinder 42 is attached with a heat preservation layer, and the inner wall of the outer cylinder 42 is provided with a plurality of uniformly distributed second blades 16.

[0057] Specifically, the heat preservation layer is made of heat preservation material (such as rock wool or glass wool), and is fixed on the outer wall of the outer cylinder 42 by skin rivets or fixing devices (such as buckles). Alternatively, the second vanes 16 are distributed equidistantly along the outer cylinder 42 (with a distance of 500-600 mm), and 6-8 groups of vanes are evenly distributed circumferentially. The second vanes 16 are inclined at an angle of 30-45° to the tangential direction of the cylinder wall, giving consideration to the dual roles of lifting the aggregate and guiding the flue gas flow.

[0058] The principles and implementation manners of the present application are described herein by using specific examples, and the above examples are only used to help understand the method of the present application and its core idea. The above description is only the preferred implementation manner of the present application. It should be noted that, due to the limited expression of the text, there are infinite specific structures in the objective world. For ordinary skilled persons in the technical field, some improvements, refinements or changes can be made without departing from the principles of the present application, or the above technical features can be combined in an appropriate manner. These improvements, refinements, changes or combinations, or the direct application of the inventive concept and technical solution to other occasions without improvement, shall be regarded as the protection scope of the present application.

Claims

1. A device for recycling and reusing asphalt pavement mixtures, characterized in that, The application relates to a regenerative drying drum (4) which comprises an inner cylinder (41) arranged obliquely, an outer cylinder (42) coaxially sleeved outside the inner cylinder (41), and a sandwich layer (43) formed between the inner cylinder (41) and the outer cylinder (42); the feeding end of the inner cylinder (41) is higher than the discharging end of the inner cylinder (41), the feeding end of the inner cylinder (41) is used for feeding virgin aggregate into the inner cylinder (41), and the feeding end of the outer cylinder (42) is used for feeding recycled aggregate into the sandwich layer (43). A drying heat source (3) is arranged at the feeding end side of the inner cylinder (41) and is used for heating the virgin aggregate in the inner cylinder (41) through flame heat radiation and down-flow high-temperature flue gas. The outer cylinder (42) heats the recycled aggregate in the sandwich layer (43) through wall heat conduction of the inner cylinder (41) and up-flow high-temperature flue gas, wherein the up-flow high-temperature flue gas is high-temperature flue gas which flows back into the sandwich layer (43) from the discharging end of the outer cylinder (42) after overflowing from the discharging end of the inner cylinder (41). A storage assembly is arranged at the discharging end side of the inner cylinder (41) and comprises a first heat-insulating and heating storage bin (5) and a second heat-insulating and heating storage bin (6) which are isolated from each other, the first heat-insulating and heating storage bin (5) is used for storing heated recycled aggregate, and the second heat-insulating and heating storage bin (6) is used for storing heated virgin aggregate. A mixing pot (10) is arranged at the bottom of the storage assembly, and after the heated virgin aggregate and the heated recycled aggregate are mixed at a certain proportion, the mixture is stirred with asphalt, a recycling agent and powder in the mixing pot (10) to obtain asphalt pavement mixture. First blades (17) are uniformly distributed on the inner wall of the inner cylinder (41), the first blades (17) control the flow velocity of the virgin aggregate and the density of the heat exchange material curtain by changing the blade angle, cooperate with the flame size of the drying heat source (3), and jointly adjust the temperature of the virgin aggregate in the inner cylinder (41) and / or the temperature of the recycled aggregate in the outer cylinder (42).

2. The asphalt pavement mixture recycling and reusing device according to claim 1, characterized in that: A self-cleaning chain (15) is arranged in the sandwich layer (43), the self-cleaning chain (15) is in contact with the inner wall of the outer cylinder (42) and rotates with the regenerative drying drum (4) to scrape off the recycled aggregate adhered to the inner wall of the outer cylinder (42); the water content of the recycled aggregate and the virgin aggregate is lower than 3%.

3. The asphalt pavement mixture recycling and reusing device according to claim 1, characterized in that: The application further comprises an air induction mechanism which comprises an air induction port arranged at the outlet end of the outer cylinder (42), the air induction port is communicated with the sandwich layer (43), the air induction port is connected with an air induction machine through an air induction pipeline, so that negative pressure is formed in the sandwich layer (43).

4. The asphalt pavement mixture recycling and reusing device according to claim 1, characterized in that: ​ 5. The asphalt pavement mixture recycling and reusing device according to claim 1, characterized in that: The discharge end of the inner cylinder (41) is communicated with the second heat preservation and heating storage bin (6), the discharge end of the outer cylinder (42) is communicated with the first heat preservation and heating storage bin (5), and the first heat preservation and heating storage bin (5) and the second heat preservation and heating storage bin (6) are provided with a metering scale (7) below, which is used for metering the heated recycled aggregate of the first heat preservation and heating storage bin (5) and the heated virgin aggregate of the second heat preservation and heating storage bin (6) in proportion and then conveying to the mixing pot (10).

6. The asphalt pavement mixture recycling and reusing device according to claim 1, characterized in that: The feeding end of the inner cylinder (41) is provided with a plurality of virgin aggregate bins (2), each of which contains virgin aggregate of different specifications, and the discharge end of each of the virgin aggregate bins (2) is provided with a corresponding first belt scale, and the feeding end of the outer cylinder (42) is provided with a plurality of recycled aggregate bins (1), and the discharge end of each of the recycled aggregate bins (1) is provided with a corresponding second belt scale; different specifications of virgin aggregate are layered and stacked into the inner cylinder (41) according to the matching requirements through the corresponding first belt scale according to the preset time sequence, and different specifications of recycled aggregate are layered and stacked into the outer cylinder (42) according to the matching requirements through the corresponding second belt scale according to the preset time sequence.

7. The asphalt pavement mixture recycling and reusing device according to claim 1, characterized in that: The drying heat source (3) is arranged at the feeding end of the inner cylinder (41), the direction of the generated flame is consistent with the inclination direction of the inner cylinder (41), and the generated high-temperature flue gas sequentially flows through the inner cylinder (41), enters the discharge end of the outer cylinder (42) from the discharge end of the inner cylinder (41), and then flows in the opposite direction in the interlayer (43).

8. The asphalt pavement mixture recycling and reusing device according to claim 1, characterized in that: The outer wall of the outer cylinder (42) is attached with a heat preservation layer, and the inner wall of the outer cylinder (42) is provided with a plurality of uniformly distributed second blades (16).

9. The asphalt pavement mixture recycling and reusing device according to claim 1, characterized in that: A regenerating agent adding mechanism and an asphalt conveying mechanism (8) are arranged at the inlet of the mixing pot (10), the asphalt conveying mechanism (8) comprises an asphalt scale and a foaming mechanism, and the asphalt is injected into the mixing pot (10) in a foamed or unfoamed state.

10. The asphalt pavement mixture recycling and reusing device according to claim 1, characterized in that: The inclination angle of the inner cylinder (41) is 3-5 degrees, the radial cross-sectional area of the inner cylinder (41) is the same as the radial cross-sectional area of the interlayer (43), and the radial height of the interlayer (43) is calculated according to the air flow rate required by the process.

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