Asphalt plant

Abstract

To provide an asphalt plant capable of producing an asphalt mixture while uniformly foaming molten asphalt.SOLUTION: An asphalt plant is equipped with a water injection nozzle 20 for injecting and adding water to molten asphalt is provided in an asphalt supply pipe 19 on the downstream side of a supply pump 18, and a stirring and mixing part 21 for mixing water and molten asphalt is provided in the asphalt supply pipe 19 on the downstream side of the water injection nozzle 20, a cylindrical body 22 having a diameter larger than that of asphalt supply piping 19 is provided, and the cylindrical body 22, an introduction part 23 and a lead-out part 24 are connected to a funnel-shaped connection part 25, and the introduction part 23 and the lead-out part 24 are connected to the cylinder 22 by shifting their respective central axes, at the intermediate position in the downward direction of the cylindrical body 22, a column body 27 is penetrated in the direction perpendicular to the downward direction, and turbulence is generated in the molten asphalt to which water flowing down the cylinder 22 is added, agitated and mixed, and then supplied to the mixer 10.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to an asphalt plant for producing an asphalt mixture, which is a road paving material, and more particularly to an asphalt plant for producing an asphalt mixture using foamed molten asphalt.

Background Art

[0002] Conventionally, when producing an asphalt mixture, a predetermined amount of water, steam, etc. is added to molten asphalt, which is a raw material of the asphalt mixture, to form it into a foam (foaming), and this foamed molten asphalt (hereinafter referred to as "foamed asphalt") is mixed with aggregates, stone powder, etc. in a mixer to produce an asphalt mixture in some cases.

[0003] As an apparatus for foaming molten asphalt, the applicant has also filed an asphalt plant as shown in Patent Document 1 (Japanese Patent Application Laid-Open No. 2020-94367), which includes a supply pump for supplying the molten asphalt measured in an asphalt measuring tank to a mixer, and a switching valve for selecting either a supply path for sending the molten asphalt into the mixer or a circulation path for sending it back to the supply pump downstream of the supply pump in the asphalt supply pipe. A water injection nozzle for injecting and adding water supplied from a water supply source to the molten asphalt is connected in the middle of the circulation path, and water is injected and added from the water injection nozzle while circulating the molten asphalt in the circulation path to foam the molten asphalt and then supply it to the mixer.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, although the above conventional device can be foamed substantially uniformly by circulating the molten asphalt with water added therein through the circulation path, the device configuration for adding the circulation path to the asphalt supply pipe only for foaming is rather large-scale and requires a certain amount of space and cost for installation. Further, if a switching failure occurs in the switching valve provided in the asphalt supply pipe, it may affect the production of the asphalt mixture, and the replacement work of the switching valve in which a problem has occurred is very troublesome.

[0006] In view of the above points, an object of the present invention is to provide an asphalt plant capable of producing an asphalt mixture by foaming molten asphalt substantially uniformly with a simple configuration.

Means for Solving the Problems

[0007] In order to solve the above problems, in the asphalt plant according to claim 1 of the present invention, a vibrating screen, an aggregate storage bin, an aggregate measuring tank, an asphalt measuring tank, and a mixer are hierarchically assembled on an elevated platform, and in the asphalt plant provided with an asphalt supply pipe and a supply pump for supplying the molten asphalt measured in the asphalt measuring tank to the mixer, a water injection nozzle for injecting water into the molten asphalt is provided in the asphalt supply pipe on the downstream side of the supply pump, and a stirring and mixing section for mixing water and molten asphalt is provided in the asphalt supply pipe on the downstream side of the water injection nozzle. The stirring and mixing section includes a cylindrical body having a larger diameter than the asphalt supply pipe, both ends of the cylindrical body are connected via a funnel-shaped connecting section to an introduction section and a discharge section, and the introduction section and the discharge section are connected to the cylindrical body with their central axes shifted. On the other hand, at an intermediate position in the flow-down direction of the cylindrical body, a columnar body is penetrated in a direction orthogonal to the flow-down direction, and the molten asphalt with water added flowing down in the cylindrical body is caused to generate a turbulent flow and stirred and mixed, and then supplied to the mixer.

[0008] Further, in the asphalt plant according to claim 2, the inner wall surface of the connecting portion that connects the cylindrical body, the introducing portion, and the discharging portion is provided with a baffle that obstructs the flow of water flowing down inside the cylindrical body and the flow of molten asphalt.

Advantages of the Invention

[0009] According to the asphalt plant described in claim 1 of the present invention, a water injection nozzle for injecting water into the molten asphalt is provided on the downstream side of a supply pump interposed in an asphalt supply pipe that supplies the measured molten asphalt to a mixer. A stirring and mixing section for mixing water and molten asphalt is provided in the asphalt supply pipe on the downstream side of the water injection nozzle. The stirring and mixing section includes a cylindrical body having a larger diameter than the asphalt supply pipe. Both ends of the cylindrical body are connected to an introducing section and a discharging section via a funnel-shaped connecting section. While the introducing section and the discharging section are connected to the cylindrical body with their central axes offset, a columnar body is passed through the cylindrical body at an intermediate position in the flowing-down direction in a direction orthogonal to the flowing-down direction, causing turbulent flow in the molten asphalt with water added flowing down inside the cylindrical body, stirring and mixing it, and then supplying it to the mixer. Therefore, by causing turbulent flow in the flow of the molten asphalt with water added flowing from the introducing section to the discharging section of the cylindrical body, water can be evenly dispersed in the molten asphalt without unevenness, and when discharging to the mixer, it is possible to supply the molten asphalt formed into a foamed state substantially uniformly. Further, the asphalt supply pipe has a simple structure without mechanical components such as a path switching valve interposed therein, enabling cost reduction and suppressing the occurrence of problems such as inability to supply molten asphalt. In addition, the simple structure can make the entire device compact, and by suppressing the installation space, it is easy to install in an existing plant.

[0010] Further, according to the asphalt plant described in claim 2, since a baffle for preventing the flow of water flowing down inside the cylinder and the flow of molten asphalt is provided on the inner wall surface of the connecting portion connecting the cylinder, the introduction portion, and the discharge portion, the molten asphalt added with water flowing down from the introduction portion to the discharge portion of the cylinder is retained inside the cylinder while generating a turbulent flow, so that the water can be more effectively dispersed uniformly, and thus the molten asphalt formed into a foam can be supplied to the mixer substantially uniformly.

Brief Description of the Drawings

[0011]

Figure 1

Figure 2

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Figure 8

Embodiments for Carrying Out the Invention

[0012] In the asphalt plant according to the present invention, in a plant having an existing structure, a water injection nozzle for injecting and adding water to molten asphalt is connected to the asphalt supply pipe on the downstream side of a supply pump such as a gear pump, which is interposed in the circular cross-section asphalt supply pipe for supplying molten asphalt from the asphalt metering tank to the mixer. The asphalt supply pipe on the downstream side of the water injection nozzle is provided with a stirring and mixing section for mixing water and molten asphalt.

[0013] The stirring and mixing section is provided with a cylinder body having a larger diameter than the asphalt supply pipe with a circular cross-section. At both ends of the cylinder body, a cylinder body with a circular cross-section, an introduction section, and a discharge section are connected by a funnel-shaped connecting section. The central axes of the cylinder body, the introduction section, and the discharge section are arranged in the same plane and parallel to each other.

[0014] Also, the central axes of the introduction section and the discharge section are slightly offset so as not to be in a straight line and are connected to the cylinder body, causing a meandering in the flow path of the molten asphalt added with water flowing from the introduction section to the discharge section. At an intermediate position in the flow-down direction of the cylinder body, a column body with a circular cross-section, for example, is penetrated in a direction orthogonal to the flow-down direction, and the molten asphalt added with water in the cylinder body is made to collide with the column body, thereby generating a turbulent flow in the molten asphalt added with water flowing through the stirring and mixing section, stirring and mixing, and enabling the molten asphalt to be supplied to the mixer in a state where the water is dispersed evenly.

[0015] When manufacturing an asphalt mixture using foamed asphalt as a raw material in the asphalt plant with the above configuration, the required amount of asphalt is calculated from the mixing ratio of the asphalt mixture to be manufactured on the plant operation panel, and the molten asphalt for one batch is measured in the asphalt weighing tank.

[0016] On the other hand, based on the mixing ratio, aggregates of each particle size are discharged from the aggregate storage bin to the aggregate weighing tank for cumulative weighing. The various materials such as the cumulatively weighed aggregates and separately weighed stone powder are put into the mixer for preliminary mixing (dry mixing).

[0017] After preliminary mixing, the molten asphalt is discharged from the asphalt weighing tank and the supply pump is driven. Water in a predetermined ratio, for example, about 1 to 3% by weight, preferably about 2% by weight of the measured amount of molten asphalt, is injected and added from the water injection nozzle to the molten asphalt flowing down through the asphalt supply pipe to the stirring and mixing section.

[0018] The water added to the molten asphalt vaporizes while flowing downward together with the molten asphalt into the stirring and mixing section. During the flow from the inlet section to the outlet section of the stirring and mixing section formed with a meandering flow path, it collides with a column body passing through the cylinder body, and accordingly, a turbulent flow is generated in the flow to cause stirring. The added water is uniformly dispersed in the molten asphalt and is led out from the outlet section to the asphalt supply pipe.

[0019] By stirring and mixing in the stirring and mixing section, the vaporizing water is uniformly dispersed in the molten asphalt, and the foamed asphalt with substantially uniform properties can be put into the mixer where the preliminary mixing is completed, and mixed with materials such as aggregates in the mixer to produce an asphalt mixture using the foamed asphalt as a raw material.

[0020] Also preferably, the connecting portion connecting the inlet portion and the cylinder body is provided with an obstructing body that prevents the molten asphalt added with water from diffusing into the cylinder body along the inner wall surface of the connecting portion where the diameter expands from the inlet portion, while the connecting portion connecting the cylinder body and the outlet portion is respectively provided with an obstructing plate that prevents the molten asphalt added with water from flowing down along the inner wall surface of the connecting portion where the diameter contracts from the cylinder body into the outlet portion.

[0021] By doing so, a part of the molten asphalt added with water introduced from the inlet portion does not collide with the column body due to the obstructing body on the inlet portion side and flows down along one inner wall surface of the cylinder body toward the outlet portion side, and is once returned into the cylinder body without being led out from the outlet portion as it is by the obstructing body on the outlet portion side and flows down from the other inner wall surface side of the cylinder body toward the inlet portion direction.

[0022] On the other hand, a part of the molten asphalt added with water introduced from the inlet portion diffuses into the cylinder body and collides with the column body while flowing down from the other inner wall surface side of the cylinder body toward the outlet portion direction, and collides with the molten asphalt added with water flowing down (returning) toward the inlet portion direction described above, so that a strong turbulent flow is generated in the cylinder body for stirring and mixing, and then it is led out from the outlet portion, whereby the molten asphalt can be supplied to the mixer in a state where the water is more effectively and uniformly dispersed.

[0023] Thus, in the molten asphalt introduced into the mixer, the water added by injection is dispersed uniformly without unevenness. Even with a simple equipment configuration in which a stirring and mixing section is interposed in the asphalt supply pipe, foamed asphalt with substantially uniform properties can be produced. By using this as a raw material, it is expected that materials such as aggregates and stone powder will be well mixed in the mixer. For example, it is predicted that a desired asphalt mixture can be produced even if the production temperature is lowered compared to the conventional temperature.

[0024] In addition, since the molten asphalt added with water is supplied to the mixer only by passing through the stirring and mixing section, the time required to discharge from the metering to the mixer is no less than the time required to discharge normal molten asphalt without adding water. Even when producing an asphalt mixture using foamed asphalt, the production efficiency per unit time does not decrease.

Example

[0025] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0026] In FIG. 1, reference numeral 1 denotes an asphalt plant for producing an asphalt mixture which is a road paving material, which is mainly composed of a plant body 2, an asphalt tank 3 for heat-insulating and storing molten asphalt, an operation panel 4 for operating and controlling various devices of the plant, and the like. The plant body 2 has an elevated platform 5 having a plurality of floors erected, and a bucket elevator 6 for lifting newly dried aggregates heated by a drier (not shown) to the upper part of the elevated platform 5 is arranged side by side on the side of the elevated platform 5.

[0027] On the elevated platform 5, a vibrating screen 7 for sieving the heated aggregates discharged from the bucket elevator 6 by particle size, an aggregate storage bin 8 for storing the aggregates sieved by the vibrating screen 7 by particle size, an aggregate weighing tank 9 for cumulatively weighing the aggregates of each particle size discharged from the aggregate storage bin 8, a mixer 10 for mixing various materials such as aggregates and molten asphalt, an asphalt weighing and supply device 11 for weighing molten asphalt and supplying it to the mixer 10, etc. are arranged in a hierarchical manner.

[0028] The asphalt metering and supply device 11 is connected with an asphalt supply pipe 12 for supplying molten asphalt from the asphalt tank 3 and a water supply pipe 14 for supplying water from a water storage tank 13 which is a water supply source. Supply pumps 15 and 16 are provided in the middle of the asphalt supply pipe 12 and the water supply pipe 14 respectively.

[0029] Figure 2 is a schematic diagram of the asphalt metering and supply device 11, which includes an asphalt metering tank 17 for metering the molten asphalt supplied through the asphalt supply pipe 12, and an asphalt supply pipe 19 equipped with a supply pump 18 such as a gear pump for supplying the metered molten asphalt to the mixer 10.

[0030] Also, in the middle of the asphalt supply pipe 19, a water injection nozzle 20 for injecting and adding the water supplied from the water supply pipe 14 to the molten asphalt is connected, and a stirring and mixing part 21 for stirring and mixing the water and the molten asphalt is interposed in the asphalt supply pipe 19 downstream of the water injection nozzle 20.

[0031] As shown in FIGS. 3 to 6, the stirring and mixing part 21 is provided with a cylindrical body 22 having a diameter about three times larger than that of the asphalt supply pipe 19, and an introduction part 23 and a lead-out part 24 with a circular cross-section are connected to both ends of the cylindrical body 22 through a funnel-shaped connecting part 25. The connecting part 25 on the introduction part 23 side has an inner diameter that expands toward the cylindrical body 22, while the connecting part 25 on the lead-out part 24 side is formed so that the inner diameter contracts toward the lead-out part 24 having an inner diameter similar to that of the asphalt supply pipe 19.

[0032] Also, the central axes of the cylindrical body 22, the introduction part 23, and the lead-out part 24 are arranged on the same plane and in parallel. Further, when the introduction part 23 is extended in the direction of the central axis α, the outer shape of the lead-out part 24 does not overlap with the outer shape of the extended introduction part 23. The introduction part 23 and the lead-out part 24 are connected to the cylindrical body 22 in a stepped manner through the connecting part 25 so that the molten asphalt added with water introduced into the stirring and mixing part 21 flows down while meandering.

[0033] Further, the connecting portion 25 is provided with a baffle 26a that prevents the molten asphalt added with water from diffusing from the introduction portion 23 into the cylindrical body 22, and a baffle 26b that prevents the molten asphalt from flowing down along the inner wall surface of the connecting portion 25 from the inside of the cylindrical body 22 to the discharge portion 24 all at once.

[0034] Also, at an intermediate position in the downward flow direction of the cylindrical body 22, there is provided a columnar body 27 having a circular cross-section that penetrates near the central axis of the cylindrical body 22 in a direction orthogonal to the plane passing through the central axes of the cylindrical body 22, the introduction portion 23, and the discharge portion 24. Further, a gap C between the inner wall surface of the cylindrical body 22 and the outer wall surface of the columnar body 27 is ensured to be approximately equal to the inner diameter of the asphalt supply pipe 19.

[0035] When water is injected and added from the water injection nozzle 20 to the high-temperature (around approximately 160 °C) molten asphalt flowing down in the asphalt supply pipe 19 into the mixer 10, the water is introduced into the stirring and mixing portion 21 while vaporizing, and is discharged from the discharge portion 24 while being stirred and mixed with the molten asphalt to form a foam approximately uniformly.

[0036] Also, the asphalt measuring tank 17 is composed of a measuring tank body 29 suspended and supported by a load cell 28, and a surge tank 30 that temporarily receives the molten asphalt discharged from the measuring tank body 29.

[0037] The upper part of the measuring tank body 29 is provided with an inlet 31 through which the discharge end of the asphalt supply pipe 12 is inserted, and the lower end is provided with a discharge port 32 for discharging the measured molten asphalt. It also includes an opening and closing mechanism composed of a cylinder 33, a piston rod 34, and a plug body 35, and the plug body 35 can be moved forward and backward in the vertical direction according to the expansion and contraction movement of the piston rod 34 to open and close the discharge port 32.

[0038] Further, in the figure, 36 is a discharge gate for discharging aggregates of each particle size stored in each compartment of the aggregate storage bin 8, 37 is a load cell for suspending and supporting the aggregate measuring tank 9 for weighing, 38 is a discharge gate for discharging the aggregates cumulatively weighed in the aggregate measuring tank 9, 39 is an asphalt injection nozzle for injecting and introducing the molten asphalt supplied from the asphalt supply pipe 19 into the mixer 10, and 40 are the mixing blades of the mixer 10.

[0039] When manufacturing an asphalt mixture using foamed asphalt as a raw material in the asphalt plant 1 having the above configuration, first, the type and production amount of the asphalt mixture to be manufactured are input into the plant operation panel 4.

[0040] The operation panel 4 discharges aggregates from each compartment of the aggregate storage bin 8 into the aggregate measuring tank 9 according to the composition of the input asphalt mixture to be manufactured and starts cumulative weighing. Meanwhile, in the asphalt measuring tank 17, the molten asphalt for one batch is weighed.

[0041] When the cumulative weighing of the aggregates is completed, it is put into the mixer 10 together with various materials such as separately weighed stone powder for preliminary mixing (dry mixing). Also, in the asphalt measuring tank 17 where the weighing of the molten asphalt is completed, the weighed molten asphalt is discharged by opening the discharge port 32 of the measuring tank body 29, and the supply pump 18 interposed in the asphalt supply pipe 19 is operated.

[0042] For the molten asphalt flowing down through the asphalt supply pipe 19 into the mixer 10, a predetermined amount of water is injected and added from the water injection nozzle 20 according to a preset water addition ratio. According to the test results conducted by the inventors, when the addition ratio of water to the molten asphalt is less than 1% by weight, the amount of water added is small and appropriate foamed asphalt cannot be obtained. On the other hand, it was confirmed that good foamed asphalt can be obtained when 2% by weight or more of water is added. However, even when comparing the asphalt mixtures using the foamed asphalt with more than 3% by weight of water added and the foamed asphalt with around 2% by weight of water added, no difference in properties was confirmed. From the above, the water addition ratio is preferably set around 2% by weight (for example, 1.5 to 2.5% by weight).

[0043] The molten asphalt to which a predetermined amount of water has been added from the water injection nozzle 20 flows down through the asphalt supply pipe 19 and is introduced from the introduction part 23 of the stirring and mixing part 21. The flow inside the stirring and mixing part 21 will be described with reference to the cross-sectional view of FIG. 6. The molten asphalt with water added, introduced from the introduction part 23, is not diffused into the cylinder body 22 by the baffle 26a provided at the connecting part 25 on the introduction side, and flows down along the inner wall surface on the lower side of the cylinder body 22 in FIG. 6 towards the outlet part 24, and is once returned towards the inner wall surface on the upper side of the cylinder body 22 by the baffle 26b provided at the connecting part 25 on the outlet part 24 side.

[0044] On the other hand, a part of the molten asphalt with water added, introduced from the introduction part 23, diffuses into the cylinder body 22 and collides with the column body 27, and while flowing down towards the inner wall surface on the upper side of the cylinder body 22 in FIG. 6, it collides with the molten asphalt with water added that is returned from the outlet part 24 side along the inner wall surface on the upper side of the cylinder body 22 towards the introduction part 23 side, causing strong turbulent flow to occur inside the cylinder body 22, and the water is stirred and mixed so as to be evenly dispersed in the molten asphalt.

[0045] In the stirring and mixing section 21, the water in the molten asphalt vaporizes while being stirred and mixed with the molten asphalt, and is led into the asphalt supply pipe 19 on the downstream side from the leading-out section 24 while being formed into a foam approximately uniformly. Then, it is introduced into the mixer 10 where the preliminary mixing has ended from the asphalt injection nozzle 39 at the downstream end, and is mixed with materials such as aggregates in the mixer 10 to produce a desired asphalt mixture.

[0046] FIG. 7 is a diagram showing another embodiment in which the stirring and mixing section 21 is rotated 90° around the central axis of the cylindrical body 22 and connected to the asphalt supply pipe 19 so that the introduction section 23 and the leading-out section 24 are horizontal. FIG. 8 is a diagram showing another embodiment in which the stirring and mixing section 21 is connected to the asphalt supply pipe 19 such that the leading-out section 24 is below the introduction section 23. As shown in FIGS. 7 and 8, even when the stirring and mixing section 21 is connected to the asphalt supply pipe 19, the flow path of the molten asphalt with water added in the stirring and mixing section 21 meanders in the same manner as described above and collides with the column body 27 in the cylindrical body 22, generating a turbulent flow and enabling stirring and mixing, and the added water can be uniformly dispersed in the molten asphalt.

[0047] In the above embodiment, an example in which the connecting portion 25 of the stirring and mixing section 21 is provided with the baffle bodies 26a and 26b has been described. However, even when the baffle bodies 26a and 26b are not present in the connecting portion 25, the molten asphalt with water added introduced into the cylindrical body 22 from the introduction section 23 collides with the column body 27 passing through the cylindrical body 22, generating a turbulent flow and being stirred and mixed in the cylindrical body 22, and the added water can be uniformly dispersed in the molten asphalt.

[0048] Also, in the above embodiment, an example in which the column body 27 having a circular cross-section passes through the cylindrical body 22 has been described. However, as long as the molten asphalt with water added flowing down from the introduction section 23 to the leading-out section 24 in the cylindrical body 22 can be made to collide with the column body 27, it is not limited to a circular cross-section. For example, even if a column body 27 such as a square column or a polygonal column passes through the cylindrical body 22, stirring and mixing can be performed in the cylindrical body 22, and the added water can be uniformly dispersed in the molten asphalt.

[0049] Also, when manufacturing an asphalt mixture using normal (water - non - added) molten asphalt as a raw material in the asphalt plant 1, in the asphalt metering and supply device 11, the molten asphalt metered in the asphalt metering tank 17 is supplied to the mixer 10 without injecting water from the water injection nozzle 20, thereby enabling the production of a normal asphalt mixture. Thus, it can flexibly respond to the production of an asphalt mixture using both foamed asphalt and normal molten asphalt as raw materials.

[0050] Also, compared with the conventional operation control, there are no major changes other than the injection control of water from the water injection nozzle 20. For an existing asphalt plant, by simply adding the water injection nozzle 20 and the stirring and mixing part 21 to the asphalt supply pipe 19, the molten asphalt can be foamed, and it can be installed relatively simply and inexpensively. Therefore, it can be preferably adopted even when applied to an existing asphalt plant.

[0051] Note that the water injection nozzle 20 connected to the asphalt supply pipe 19 for injecting and adding water to the molten asphalt can be, for example, arranged and connected with two water injection nozzles 20 at opposite positions of the asphalt supply pipe 19, or a plurality of water injection nozzles 20 can be arranged and connected with a predetermined angular shift in the circumferential direction of the asphalt supply pipe 19. Various changes can be made as long as water can be injected and added to the flowing molten asphalt.

Industrial Applicability

[0052] The present invention can be widely applied to an asphalt plant for manufacturing an asphalt mixture using foamed asphalt as a raw material.

Explanation of Reference Numerals

[0053] 10…Mixer 11…Asphalt metering and supply device 17…Asphalt metering tank 18…Supply pump 19…Asphalt supply pipe 20…Water injection nozzle 21…Stirring and mixing part 22…Cylindrical body 23... Introduction part 24... Outlet part 25... Connecting part 27... Cylindrical body

Claims

1. In an asphalt plant in which a vibrating screen, an aggregate storage bin, an aggregate measuring tank, an asphalt measuring tank, and a mixer are stacked in layers on an elevated platform, and an asphalt supply pipe and a supply pump for supplying the molten asphalt measured in the asphalt measuring tank to the mixer are provided, a water injection nozzle for injecting water into the molten asphalt is provided in the asphalt supply pipe on the downstream side of the supply pump, and a stirring and mixing section for mixing water and molten asphalt is provided in the asphalt supply pipe on the downstream side of the water injection nozzle. The stirring and mixing section includes a cylindrical body having a larger diameter than the asphalt supply pipe, and both ends of the cylindrical body are connected via a funnel-shaped connecting section to an introduction section and a discharge section, and the introduction section and the discharge section are connected to the cylindrical body with their central axes shifted. Meanwhile, a column body is passed through in a direction perpendicular to the flow direction at an intermediate position in the flow direction of the cylindrical body to cause a turbulent flow in the molten asphalt with water added flowing through the cylindrical body, and after stirring and mixing, it is supplied to the mixer. An asphalt plant characterized by this.

2. The asphalt plant according to claim 1, wherein inner wall surfaces of the connecting sections connecting the cylindrical body to the introduction section and the discharge section are each provided with a baffle body that obstructs the flow of water and molten asphalt flowing through the cylindrical body.

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