JP2748970B2 - Nozzle equipment for foam door asphalt manufacturing equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a production apparatus for producing foamed asphalt from heated asphalt and a small amount of water.

[0002]

BACKGROUND OF THE INVENTION Asphalt mixtures used for road pavement are produced by mixing aggregates such as crushed stones and sand with asphalt. However, asphalt is a highly viscous material and is solid at room temperature. Therefore, in order to produce an asphalt mixture, the asphalt needs to be in a liquid state before being injected into the mixer. Four methods are generally known for liquefying asphalt. Heating to a high temperature (150-180 ° C.), cutting back, emulsifying and foaming.

[0003] Heating asphalt to high temperatures reduces the viscosity of the asphalt sufficiently, but when it comes into contact with cold-wet aggregate, the asphalt solidifies rapidly, and peeling and insufficient bonding with the aggregate occur. Therefore, asphalt plants are equipped with aggregate heat drying loads. These plants are commonly known as heat mixing plants,
Suitable for producing good quality asphalt mixtures. However, they consume large amounts of fuel, pollute the atmosphere with hydrocarbons and the like, and large equipment, burners and dryers contribute to noise pollution.

[0004] Cutback uses a solvent to reduce the viscosity of asphalt. Solvents are generally volatile and evaporate leaving asphalt in the mixture. However, many contaminants are released into the atmosphere as the solvent evaporates, which makes cut packs generally not environmentally recognized. Furthermore, the need to heat dry the aggregate is not ruled out, and there is a risk of explosion as the diluted asphalt is sprayed on the heated aggregate.

[0005] Emulsified asphalt is produced by mechanically miniaturizing heated asphalt and dispersing it in water containing an emulsifier. As with cutback, water evaporates leaving asphalt. The viscosity of the asphalt is significantly reduced, allowing it to be mixed with cold aggregates. However, the emulsion contains a large amount of water (4
0%) and this technique cannot be performed in rainy weather when the emulsion is washed away. Further, it takes a lot of time to evaporate water to such an extent that traffic can be opened. Furthermore, another disadvantage with large amounts of water is that only 60% of the asphalt enters the transporting tank truck.

[0006] Foam door asphalt is obtained by putting air and a small amount of water (1-2% based on the asphalt amount) into heated asphalt. When water comes into contact with asphalt, it becomes water vapor surrounded by countless micro-asphalt bubbles. The volume of asphalt can be as much as 20 times. The viscosity is also very low and mixing with cold aggregates is also possible. Foamed asphalt, unlike emulsions and cutbacks in which asphalt changes chemically, merely changes physically. Also, the curing time is almost negligible compared to emulsions since water is not added in large amounts to the mixture. Also,
Since it does not release carbohydrates into the atmosphere, it is environmentally safe.

Formed asphalt is a promising method because it does not require the aggregates to be heated and dried, thus reducing the size of the plant. Plants without dryers can eliminate pollution and reduce equipment costs. Since the foamed asphalt mixture can be stored at room temperature, the storage silo does not require any heating equipment. Furthermore, since the room-temperature mixture can be produced not only in a plant but also directly on site using a road stabilizer, it can be said that it is the simplest and simplest method in recent years. The manufacturing method and equipment required for the form asalt are disclosed in Japanese Patent Publication No. 52-8332. However, the disclosed method and equipment have the following disadvantages.

[0008] Each of the nozzles N1 to N3 shown in FIGS.
Has its own asphalt and water mixing chambers C1-C3. However, when the production of foamed asphalt is stopped, some asphalt remains in the chambers C1 to C3 and solidifies immediately. During the repetition of two or three times, the nozzles N1 to N3 are completely clogged with asphalt and become inoperable.

The apparatus shown in FIGS. 8-11 is a premixing chamber M1-M4 for promoting asphalt foaming by mixing asphalt and water before foam asphalt is injected. This not only causes a lack of consistency, but also causes the chamber to become clogged with asphalt. It is possible to install an electric heater to prevent this clogging, but asphalt will contact the hot equipment, causing oxidation and producing sludge. This phenomenon is generally well known.

In the examples shown in FIGS. 12 to 15, the asphalt spray valve V1, the water valve V2 and the spray nozzle N are far apart. When this system goes down,
Much of the asphalt remains in the piping and cools, clogging the entire device. In particular, in FIG. 15, the injection amount from each nozzle becomes uneven. In addition, the code | symbol AS in a figure is asphalt and W is water.

Therefore, the above-mentioned device requires frequent cleaning and is very difficult to use. Furthermore, it is difficult to precisely adjust the ratio of water to asphalt, resulting in inhomogeneous quality.

[0012]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a nozzle apparatus for a foam door asphalt manufacturing apparatus capable of preventing clogging of the apparatus and obtaining uniform and high quality foam door asphalt. I have.

[0013]

According to the present invention, there is provided an apparatus for producing foamed asphalt from heated asphalt and a small amount of water, the apparatus comprising a flow control valve and a nozzle portion, wherein the flow control valve is heated asphalt. Switching means for selectively switching a supply line to a return line to the nozzle portion or the asphalt tank, the nozzle portion includes respective inlets for water and compressed air, and supplies water and compressed air to the supplied heated asphalt. A mixing chamber for forming foam door asphalt by injecting and mixing is provided and a nozzle hole.

Further, according to the present invention, a plurality of flow control valves are arranged in a row in the heat insulation case, and both ends of the heat insulation case are connected to a heated asphalt supply line and a return line to the asphalt tank, respectively. There is provided interlocking means for switching means of the flow control valve and opening and closing means on the return line side of the heat retaining case.

In the present invention constructed as described above, when the injection of the foam door asphalt is stopped at the end of the work, the introduction pipe is switched to the discharge pipe and the heated asphalt is returned to the asphalt tank to solidify the asphalt. prevent. At the same time, the supply of air into the mixing chamber is continued until all foam door asphalt in the mixing chamber is discharged, thereby preventing clogging with foam door asphalt.

[0016]

Embodiments of the present invention will be described below with reference to the drawings.

In FIG. 1, an asphalt tank 1 is
The asphalt AS is stored and includes a heating device and a heat insulating cover (not shown).
Maintained at 160 ° C. The heated asphalt AS is returned to the asphalt tank 1 by the variable discharge pump 2 via the inflow pipe 3, the flow control valve 5 and the discharge pipe 8.
This recirculation is performed even when foam door asphalt is not manufactured, and the asphalt AS in the circuit is used.
Is prevented from sticking.

The flow control valve 5 adjusts the amount of asphalt to either the discharge pipe 8 or the nozzle section 4, and the nozzle section 4 is connected to the expansion chamber 6 and the nozzle 31 (FIG. 2). Consists of The flow control valve 5 is provided with a switching valve 1 by compressed air of a compressor 9.
0 is operated by the air cylinder 7. The compressed air is supplied to the expansion chamber 6 via the pressure regulator 11 and the on / off valve 12 by the supply line 13.

On the other hand, water W is stored in a water tank 14 and is expanded by a water pump 15 and a supply line 16.
Supplied to The water pressure is adjusted by the regulator 17,
The water pressure is displayed on the water pressure gauge 21c of the control panel 18, and the water amount is displayed on the high-precision flow meter 22. The control panel 18 is provided with a switching valve controller 19, an asphalt thermometer 20, an air pressure gauge 21a, and an asphalt pressure gauge 21b.

In FIG. 2, the flow control valve 5 is constituted by a rotary valve, and the inlet 23 passes through the passages 25a and 25a depending on the position of the circular valve 24 fixed to the shaft 26.
b, it is selectively switched to the nozzle section 4 side or to the discharge port 27 side through the passages 25b and 25c. The switching is performed by rotating a lever 33 fixed to the shaft 26 with the piston rod 7a of the air cylinder 7. FIG. 2 shows a state in which the cylinder 7 is contracted and the inlet 23 is switched to the nozzle section 4 side. Is shown. The air cylinder 7 and the lever 33 constitute switching means.

A mixing chamber 30 is formed in the expansion chamber 6 of the nozzle section 4 and has an air inlet 28 connected to the supply line 13 for compressed air A and a water inlet 28 connected to the water supply line 16. A nozzle 31 having a nozzle hole 32 is provided at the lower end.

Next, the operation will be described.

In the mixing chamber 30, when the heated asphalt AS comes into contact with the water W, the water W rapidly changes into steam and is mixed with the compressed air A into the asphalt AS. Under these conditions, asphalt AS becomes foam door asphalt and expands to 20 times its original volume,
It is injected from the nozzle hole 32.

The mixing ratio of asphalt and water varies depending on the conditions. However, in order to produce a pavement material using ordinary materials, water of 1 to 2% with respect to the asphalt amount is suitable. The required amount of asphalt depends on the properties of the materials used. As with the water for forming and coating, the pressure and temperature of the asphalt depend on the required formulation design. Additives may be added to asphalt or water to improve foam properties. The supply of asphalt is adjusted by adjusting the variable discharge pump 2 and the amount of water is adjusted by reading the flow meter 22.

When the injection of foam door asphalt is stopped, such as at the end of the operation, the air cylinder 7 is extended, the lever 33 is rotated clockwise, and the inlet 23 is passed through the passage 25.
By switching to the outlet 27 via b and 25c, the asphalt AS is returned to the tank 1, the inlet pipe 3, the discharge pipe 8 and the flow control valve 5 are kept at a high temperature to prevent the asphalt AS from solidifying. Further, the supply of the air A to the chamber 30 is continued until all the foam door asphalt in the mixing chamber 30 is discharged from the nozzle holes 32, thereby preventing the clogging of the nozzle 31 due to the residual foam door asphalt 1.

FIG. 3 shows another embodiment of the present invention, that is, an apparatus for injecting foamed asphalt with a wide width. The long heat retaining case 50 is provided with a plurality (16 in the illustrated example) of flow control valves 5 with the nozzle portion 4 facing downward in a row. At one end of the heat retaining case 50, an asphalt inflow portion 51 is provided, and at the other end,
A discharge section 52 is provided and connected to the inflow pipe 3 and the discharge pipe 8 shown in FIG.

The lever 33 of the flow control valve 5 is
An air cylinder 55 is interposed between the case 50 and a bracket 54 which is pivotally attached to the flat bar 53 and erected on the flat bar 53.

On the other hand, an on-off valve 5
The end of the actuating lever 57 of the valve 56 and the bracket 54 is connected by a rod 58.
That is, the switching of the flow control valve 5 and the discharge unit 52
Opening and closing are linked. In this embodiment, the cylinder 5
When the valve 5 is contracted, all the levers 33 rotate counterclockwise to supply asphalt to the nozzle part 4 and the on / off valve 56 is closed by the rod 58 and the lever 57. Further, when the width is reduced, the connection with the flat bar 53 of the required lever 33 may be released from both ends.

FIG. 4 shows an example of a plant for producing foam door asphalt using a nozzle device embodying the present invention. 1 to 3 are denoted by the same reference numerals, and redundant description will be omitted. In this plant, the aggregates A1, A2 used are adjusted by adjusting gates G1, G2 and the belt conveyors B1, B2.
To the mixer M. The material A3 in the silo S is placed on the belt conveyor B2. Examples of the material of the material A3 include cement, lime, bentonite, and the like. Figure 1
The foam door asphalt described in FIG. 3 is injected and mixed at the inlet of the mixer M. The mixture is transported on a belt conveyor B3 and stored as a product C. As previously described, this product C is a room temperature mixture and does not cure by cooling as does a heated mixture. The mixture can therefore be stored for 30 to 40 days without added cement, without changing its quality by preventing rain.

[0030]

According to the present invention, as described above, the clogging of the apparatus when the injection of foam door asphalt is stopped can be reliably prevented.

Further, the ratio of water to asphalt can be accurately adjusted to obtain uniform and high quality foam door asphalt.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram showing an embodiment of the present invention.

FIG. 2 is a front sectional view showing a flow control valve.

FIG. 3 is a front view showing another embodiment of the present invention.

FIG. 4 is a drawing showing an example of a plant for producing foam door asphalt using a nozzle device embodying the present invention.

FIG. 5 is a side sectional view showing an example of a conventional nozzle.

FIG. 6 is a side sectional view showing another example of a conventional nozzle.

FIG. 7 is a side sectional view showing another example of a conventional nozzle.

FIG. 8 is a side sectional view showing an example of a conventional premixing chamber.

FIG. 9 is a side sectional view showing another example of the conventional premix chamber.

FIG. 10 is a side sectional view showing another example of the conventional premix chamber.

FIG. 11 is a side sectional view showing another example of the conventional premix chamber.

FIG. 12 is a side view showing an example of a conventional nozzle device.

FIG. 13 is a side view showing another example of the conventional nozzle device.

FIG. 14 is a circuit diagram showing another example of a conventional nozzle device.

FIG. 15 is a perspective view showing another example of a conventional nozzle device.

[Explanation of symbols]

 A1, A2: Aggregate A3: Material B1 to B3: Belt conveyor C: Product C1 to C3: Mixing chamber M: Mixer M1 to M4: Premix chamber N ··· Water nozzles N1 to N3 ··· Nozzle S · · · Silo V1 · · · Asphalt spray valve V2 · · · Water valve 1 · · · Asphalt tank 2 · · · Variable discharge pump 3 · · · Inflow pipe 4 · ..Nozzle part 5 ・ ・ ・ Flow control valve 6 ・ ・ ・ Expansion chamber 7, 55 ・ ・ ・ Air cylinder 7a ・ ・ ・ Piston rod 8 ・ ・ ・ Discharge pipe 9 ・ ・ ・ Compressor 10 ・ ・ ・ Switching valve 11 ・..Pressure regulators 12, 56 ... On-off valve 13 ... Supply line 14 ... Water tank 15 ... Water pump 16 ... Supply line 17 ... Controller 18 ... Control Panel 19: Switching valve controller 20: Asphalt thermometer 21a: Air pressure gauge 21b: Asphalt pressure gauge 21c: Water pressure gauge 22: High precision flow meter 23: Inlet 24 ... Circular valves 25a to 25c passage 26 shaft 27 outlet 28 air inlet 29 water inlet 30 mixing chamber 31 nozzle 32 Nozzle hole 33 Lever 50 Heat insulation case 51 Inlet 52 Outlet 53 Flat bar 57 Lever 58 Rod

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Mitsuo Fukukawa 1-7-27 Koraku, Bunkyo-ku, Tokyo Kashima Road Co., Ltd. (56) References JP-A-6-320072 (JP, A) JP-A-59-177154 (JP, A) JP-A-9-31911 (JP, A) JP-A-4-16603 (JP, A) JP-A-1-187202 (JP, A) , U) Japanese Utility Model Hei 7-2507 (JP, U) Japanese Patent Publication No. 43-2026 (JP, B1) (58) Fields investigated (Int. Cl. ⁶ , DB name) B05B 7/00-7/32 C08L 95/00 E01C 19/12-19/17

Claims (2)

(57) [Claims] 1. A manufacturing apparatus for manufacturing foam door asphalt with heated asphalt and a small amount of water, comprising a flow control valve and a nozzle portion, wherein the flow control valve connects a heated asphalt supply line to the nozzle portion or the asphalt tank. The nozzle section is provided with respective inlets for water and compressed air, and water and compressed air are injected and mixed into the supplied heated asphalt to form door asphalt. A nozzle apparatus for a foam door asphalt manufacturing apparatus, comprising: a mixing chamber to be formed; and a nozzle hole. 2. A plurality of flow control valves are arranged in a row in a heat insulation case, both ends of the heat insulation case are connected to a heated asphalt supply line and a return line to an asphalt tank, respectively, and the plurality of flow control valves are switched. 2. A nozzle device for an apparatus for manufacturing foam door asphalt according to claim 1, further comprising an interlocking means for interlocking the opening and closing means on the return line side of the heat retaining case.