JP2000084433A - Aggregate recovery system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an aggregate recovery system which can produce a coarse aggregate and a fine aggregate which is reduced in an amount of matters adhered thereto. SOLUTION: A solid such as concrete waste is ground and kneaded by a vertical grinding and kneading device to remove an adhesion component from the surface of aggregate as impalpable powder. At this time, the heat of hot air blowing from a blowing pipe of a main body causes good peel off of the impalpable powder due to a difference between the thermal expansion coefficient of the impalpable powder and that of the aggregate. The ground and kneaded concrete waste is classified into a coarse aggregate (5 mm or more) and a fine aggregate (less than 5 mm) by an aggregate recovery device 15 equipped with wire netting having a mesh size of 5 mm. As a result, the coarse aggregate and fine aggregate from which a mortar component and the like have been removed sufficiently can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an aggregate recovering system, and more particularly to an aggregate recovering system capable of separating solid matter such as waste concrete into coarse aggregate and fine aggregate.

[0002]

2. Description of the Related Art As a conventional aggregate recovery system, for example, one disclosed in Japanese Patent Application Laid-Open No. Hei 4-21550 is known. This is composed of pretreatment means for raw material waste concrete, which is an example of solid matter, separation and collection means for coarse aggregate, and separation and collection means for fine aggregate. In other words, waste concrete removed from the demolition site includes steel bars, wood chips,
Soil, brick debris, etc. are often mixed. Also, their sizes vary. Therefore, the concrete waste is roughly crushed to about 20 to 100 mm, and the rebar is removed by a magnetic separator. Next, since the strength of the cement hydrate is smaller than that of the aggregate in the waste concrete, the waste concrete is divided at the bonding portion between the aggregate and the cement hydrate, and the cement hydrate is scraped off.

[0003]

However, in such conventional separation of aggregate, a considerable amount of hardened paste (also referred to as cement) adhered to the recycled fine aggregate. When concrete is manufactured using the aggregate to which the cement component is attached, the strength of the attached cement component is lower than the strength of the aggregate itself, and this is a weak point in the strength of the hardened concrete. Moreover, since the aggregate to which the cement component is attached has a large water absorption, if it is used for concrete, drying shrinkage of the concrete increases, and there is a problem with durability such as a decrease in freeze-thaw resistance.

[0004]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an aggregate recovering system for obtaining coarse aggregate and fine aggregate having a small amount of adhered cement. Another object of the present invention is to provide an aggregate recovery system capable of efficiently regenerating aggregate having a small amount of adhered cement from solid matter, particularly waste concrete.

[0005]

According to the first aspect of the present invention, there is provided a cylindrical main body which is vertically erected and into which solid matter such as concrete waste material is charged from above, and which is rotatable inside the main body. A stirring member arranged to stir the solid material;
A vertical milling device having a rotatable table feeder disposed at a predetermined distance from the lower end of the main body to discharge the ground solid, and the ground solid And a fine powder discharging means for supplying air to the inside of the main body from below and discharging fine powder from above the main body. .

According to a second aspect of the present invention, there is provided the aggregate recovery system according to the first aspect, wherein the solid matter such as the concrete waste material is heated.

According to a third aspect of the present invention, there is provided a cylindrical main body which is vertically erected and into which solid matter such as concrete waste material is loaded from above, and which is rotatably disposed inside the main body. A vertical milling device having a rotatable table feeder disposed at a predetermined distance between the stirring member for stirring the solid and the lower end of the main body and discharging the ground solid. Classifying means for classifying the ground solids into coarse aggregate and fine aggregate, and fine powder discharging means for supplying hot air to the inside of the main body from below and discharging fine powder from above. This is an aggregate recovery system including: In addition, the temperature of this hot air is 300-500 degreeC.

According to a fourth aspect of the present invention, in the first aspect of the present invention, the vertical milling device has a surfactant supply means for supplying a surfactant into the main body. It is an aggregate recovery system of the description.

[0009]

According to the invention as set forth in claims 1 to 4, first,
A solid material such as concrete waste is rubbed with a vertical rubbing device. By this rubbing, the solid component removes the adhering component from the aggregate surface as a fine powder. The rubbed concrete waste material is usually separated from the coarse aggregate (5%) by a classification means provided with a wire mesh having a mesh size of 5 mm.
mm or more) and fine aggregate (less than 5 mm). As a result, a coarse aggregate and a fine aggregate from which cement and the like are sufficiently removed can be obtained. At the time of rubbing, the fine powder discharging means supplies cold air (when the solids are heated) or hot air from the lower part of the inside of the main body. Is discharged and removed from the upper part of the main body. On the other hand, the solid matter that has undergone the rubbing treatment is discharged from the lower part of the main body through the table feeder. In the case of claim 2, the solid is heated in advance and air is supplied thereto. In the case of the third aspect, when the solid is not heated, hot air of a predetermined temperature is supplied from the lower portion inside the main body instead of simple air. As a result, exfoliation of the heated solid is promoted due to a difference in expansion coefficient. Therefore, the fine powder can be efficiently exfoliated and discharged to the outside.

[0010] In particular, in the present invention according to claim 4, when the surfactant is supplied into the main body from the surfactant supply means at the time of grinding the solid material, the surfactant is removed from the ground material which has been subjected to the grinding process. Since it adheres to the surface and covers this surface, it is possible to prevent the fine powder once separated from re-adhering to the solid. As a result, the fine powder can be easily discharged to the outside.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 4 are views showing an aggregate recovery system according to a first embodiment of the present invention. As shown in FIG. 1, this aggregate recovery system includes a concrete waste measuring device 11 which is an example of a solid material, a vertical ground milling device 14 for grinding and processing concrete waste heated by hot air, and an aggregate. And a collecting device 15.

In the measuring device 11, concrete waste material having a particle size of, for example, 40 mm or less after the rebar is separated and recovered is supplied. This concrete waste material is supplied to the rubbing device 14 by a predetermined amount, and the rubbing device 14 is heated to 300 ° C to 500 ° C with hot air at 100 ° C to 3 ° C.
It is heated to a predetermined temperature in the range of 00 ° C. As the measuring device 11, any device that can supply a constant amount of concrete waste material can be used, and a hopper scale, a belt scale, or the like can be used.

Next, the vertical milling device 14 will be described in detail with reference to FIGS. In these figures, reference numeral 110 denotes a cylindrical main body which is vertically erected, and a table feeder 120 is provided below the main body 110.
Are coaxially fixed. Further, a rotating body 130 having the same axis as the main body 110 is rotatably arranged inside the main body 110. The rotating body 130 is rotatably supported on a vertical axis as a center of rotation by a motor 140 fixed above the main body. The rotating body 130 has a cylindrical shaft 1
50 and a steel bar 160. The plurality of steel rods 160 functioning as a stirring member for waste concrete material have a predetermined length, and are protruded horizontally on the outer peripheral surface of the cylindrical shaft 150. Specifically, these steel rods 160 are arranged at regular intervals along the length direction of the cylindrical shaft 150, and at equal angular intervals of approximately 90 degrees along the circumferential direction of the outer peripheral surface of the cylindrical shaft 150. It is protruding.

A supply port is opened on the upper side surface of the main body 110, and a supply pipe 170 for concrete waste material is connected and fixed to the supply port at a predetermined angle. Also, the main body 1
In the upper part of 10, at a position opposite to the supply pipe 170,
An air discharge pipe 830 is provided. The discharge pipe 830 is connected to a dust collector (not shown). On the other hand, in the lower part of the main body 110, a hot air blowing pipe 81 as an example of a fine powder discharging means is provided.
0,820 are provided 180 degrees apart in the circumferential direction. Hot air of 450 ° C. is supplied obliquely downward from the blowing pipes 810 and 820 into the main body 110. The hot air is obtained by heating the air by, for example, a burner, but other heat sources can be used. Note that air at room temperature may be used instead of hot air.

A rotating body 1 is provided in a lower portion of the main body 110.
A predetermined space 180 is formed below the space 30, and the space 180 communicates with an external space of the main body 110 via a predetermined gap 190 between the space 180 and the upper surface of the table feeder 120. Therefore, the concrete waste material charged from the supply port on the upper part of the main body 110 gradually falls through the part (the middle part of the main body) provided inside the rotating body 130, and this space 18
From 0, it is discharged to the upper surface of the table feeder 120 outside the main body through the gap 190. The upper surface is made of a refractory 260 having a predetermined thickness.

The aggregate excluding the fine powder in the concrete waste discharged to the upper surface of the table feeder 120 is guided by the scraper 210 and sent to the discharge unit 220. Scraper 210 as a plate material
Is fixed to the lower end of the main body 110, and extends radially outward from the rotation center of the table feeder 120 at a predetermined angle with respect to the radial direction. Moreover, the tip of the table feeder 120 protrudes from the outer edge of the table feeder 120 by a predetermined length.

The main body 110 is configured such that it can be ventilated from its lower part and this air can be sucked from its upper part by a fan. Therefore, the fine powder generated by the rubbing of the concrete waste material is discharged to the outside by the rising airflow. Also, the main body 110
Inside, the load of the motor 140 for driving the rotating body 130 is made constant by a control device in order to keep the level of the inserted concrete waste material constant. This is motor 14
The feedback control is performed by adjusting the rotation speed of the table feeder 120 based on the zero load.

Returning to FIG. 1, the concrete waste rubbed by the rubbing device 14 is then supplied to an aggregate collecting device 15. This recovery device 15 is constituted by a vibrating sieve as a classification means. With this sieve, the aggregate is classified into coarse aggregate (aggregate having a particle size of 5 mm or more) and fine aggregate (aggregate having a particle size of less than 5 mm). Aggregate is recovered from under the net. As shown in FIG. 4, the vibrating sieve 15 includes a sieve body 52 suspended from a gantry 51, a wire mesh 53 having a predetermined mesh size (5 mm) stretched inside the sieve body 52,
A vibrator 54 is attached to the upper portion of the sieve main body 52 and vibrates the vibrator. Also, the sieve body 52
A collection box 56 for fine aggregates, etc.
Further, a collection box (drum can) 58 for coarse aggregate is provided below the side discharge port 57 of the sieve body 52. The chute 59 of the scraped concrete waste material is disposed above the sieve body 52.

In the aggregate recovery system according to the above configuration, concrete waste material that has been pretreated, that is, crushed, and whose rebar and the like have been sorted and separated by magnetic force is first measured by the measuring device 11. Next, hot air is blown in the vertical milling device 14 to rub it, thereby easily removing adhering components from the surface of the aggregate. That is,
The components (such as cement) adhering to the aggregate of the concrete waste material are weakened by the heating of the hot air, and the cement easily separates from the surface of the aggregate due to a difference in thermal expansion coefficient between the cement and the aggregate. . The heated concrete waste material is gradually aggregated while being stirred by the steel bar 160 of the rotating body 130, while the fine powder of the cement, which has been peeled off at this time, is blown up by the rising flow of hot air to the outside. Is discharged. Next, the rubbed aggregate is collected by the collecting device 15.
In the above, the coarse and fine aggregates are separated and collected. In this way, the concrete waste is separated into coarse aggregate, fine aggregate, and fine powder and collected. Cement and the like are not adhered to the surfaces of the collected coarse aggregate and fine aggregate, and are provided for reuse like new products.

The specific operation of the vertical milling device 14 will be described with reference to FIGS. In the vertical milling device 14, the concrete waste material is continuously supplied from the supply pipe 170. The concrete waste material supplied into the main body 110 gradually falls while being stirred and stirred by the steel rod 160 of the rotating body 130. The level of the concrete waste inside the main body 110 is always kept constant by a control system (not shown). While falling inside the main body 110, the components adhering to the outer surface of the concrete waste material are peeled from the outer surface by being rubbed with the rotating steel bar 160 or the like.
And these components that became fine powder (such as cement)
Is discharged out of the main body by the upward flow.

That is, hot air is blown into the blowing pipes 810, 82.
As a result, the strong upward flow of air
Is formed inside. With this upward flow, the fine powder generated at the time of rubbing is discharged from the discharge pipe 830. As described above, the heat of the hot air at 450 ° C. weakens the cement and the like adhering to the aggregate, and facilitates the separation of the cement from the aggregate surface due to the difference in thermal expansion. As a result, the fine powder adhering to the aggregate is easily blown up by the rising flow of the hot air. In this way, the fine powder is discharged early and reliably. By blowing the hot air, it is not necessary to heat the concrete waste material in advance.
Therefore, a preliminary heating device or the like becomes unnecessary. The hot-air blowing pipe can be composed of, for example, four (or more) blowing pipes separated by 90 ° in the circumferential direction of the main body. Hot air is evenly blown in the circumferential direction to increase the efficiency of rubbing and enhance the effect of separating and discharging fine powder.

The dropped concrete waste becomes only the aggregate by grinding, and is discharged from the space 180 through the gap 190 to the upper surface of the table feeder 120 outside the main body 110. Thereafter, the concrete waste material moves radially outward on the upper surface of the refractory 260 and is discharged to the discharge part 220 by the scraper 210. Then, it is sent to the next step.

FIG. 5 shows a second embodiment of the aggregate recovery system according to the present invention. In this embodiment, as the vertical milling apparatus, a concrete waste material supply pipe 170 at the upper part of the main body 110 is provided with a fixed discharge pump 101 for supplying a surfactant into the pipe. The pump 101 is supplied into the main body 110 through a discharge pipe 102 and a supply pipe 170 in a predetermined amount (for a concrete waste material, a predetermined amount of 0.1.
1 to 0.5% by weight) of a surfactant (diethylene glycol). The supplied surfactant prevents the fine powder once separated from reattaching to the aggregate, and ensures the separation and discharge of the fine powder and the aggregate. Note that the surfactant is not limited to diethylene glycol. For example, ethylene glycol, propylene glycol, triethylene glycol, ethylene glycol dimethyl ether and the like may be used. Other configurations, operations, and effects of the rotating body 130, the table feeder 120, and the like are the same as those in the first embodiment.

FIG. 6 shows a third embodiment of the aggregate recovery system according to the present invention. Here, another type of vertical milling device is employed. That is, this device
An inner hole 610 of the cylindrical shaft 150 of the rotating body 130 is used as an air passage, and air is supplied from the upper portion of the cylindrical shaft 150 to the inside of the main body through a plurality of openings 620 formed at the lower end of the cylindrical shaft 150 through the inner hole 610. Have. Air is supplied to the space 180 through the inner hole 610, and when the air rises inside the main body 110, the fine powder is involved and is discharged to the outside from the discharge pipe 630. The opening 620 is the rotating body 1
30 at equal intervals in the circumferential direction (for example, 6 to 12).
Pieces) are arranged. In this embodiment, there is no need to dispose the air blowing tube below the main body 110. The structure of the main body can be simplified. Further, the supplied air may be hot air at 300 to 500 ° C., for example. Further, even in this embodiment, the surfactant may be supplied to the supply pipe 170 of the concrete waste material at a predetermined ratio. Other configurations and operations are the same as those in the above embodiment.

FIG. 7 shows a fourth embodiment of the aggregate recovery system according to the present invention. In this embodiment, another type of vertical milling device is employed. That is, the main body 710 is mesh-shaped (for example, the mesh size is 5 mm).
Or a large number of through holes of the same size, and the fine powder is discharged to the outside from this mesh portion. The main body 710 is covered with an outer cylinder 720. Inner hole 61 of cylindrical shaft 150
The air supplied from 0 is blown out into the main body 710 through the hole 730 and further discharged through the mesh portion through the discharge pipe 740 to the dust collector. According to this embodiment, the fine powder can be discharged more efficiently, and it is possible to achieve a further efficient rubbing treatment. Other configurations and operations are the same as those in the above embodiment.

FIG. 8 shows a fifth embodiment of the aggregate recovery system according to the present invention. In this embodiment, after weighing by the measuring device 11, the concrete waste material before being put into the rubbing device 14 is put into the heating device 12, where hot air is blown, and the concrete waste material is previously blasted.
This is an example in which heating is performed to 0 ° C to 300 ° C. The concrete waste put into the heating device 12 is heated in a vertical heating furnace, and then discharged to the outside by a table feeder coaxially arranged below the furnace. of course,
The discharge surface of the concrete waste of the table feeder is made of refractory. In the case of the fifth embodiment, the air blown into the rubbing device 14 does not have to be hot air. For example, it is also possible to supply air at a room temperature at a predetermined air volume. Even with such a configuration, the same effects as in the above embodiments can be obtained.

[0027]

According to the present invention, cement and the like as adhering components can be sufficiently removed from the surface of solid matter such as waste concrete, and can be reused as recycled aggregate. Therefore, concrete can be manufactured using this recycled aggregate. In this case, problems such as durability do not occur. In addition, with the vertical milling device,
It is possible to perform a large-scale treatment of ground rice of solids.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing an aggregate recovery system according to a first embodiment of the present invention.

FIG. 2 is a longitudinal sectional view showing a vertical milling device according to the first embodiment of the present invention.

FIG. 3 is a sectional view showing a steel rod according to the first embodiment of the present invention.

FIG. 4 is a front view showing a vibration sieve according to the first embodiment of the present invention.

FIG. 5 is a longitudinal sectional view showing a vertical milling device according to a second embodiment of the present invention.

FIG. 6 is a longitudinal sectional view showing a vertical milling device according to a third embodiment of the present invention.

FIG. 7 is a longitudinal sectional view showing a vertical milling device according to a fourth embodiment of the present invention.

FIG. 8 is a schematic view showing an aggregate recovery system according to a fifth embodiment of the present invention.

[Explanation of symbols]

 14 vertical milling device, 15 aggregate recovery device (classification means), 101 metering pump (surfactant supply means), 110 body, 120 table feeder, 160 steel rod (stirring member), 810,820 air blowing pipe ( Fine powder discharging means).

 ──────────────────────────────────────────────────の Continued on the front page (72) Inventor Hiroyuki Matsuda 1-1, Donanmachi, Yawatanishi-ku, Kitakyushu, Fukuoka Prefecture Inside the Cement Development Center of Mitsubishi Materials Corporation (72) Inventor Yusuke Nishimura, Tonanmachi, Yawatanishi-ku, Kitakyushu, Fukuoka Prefecture No. 1-1 In the Cement Development Center of Mitsubishi Materials Corporation (72) Inventor Masaharu Yoshida 1-1-1 Donanmachi, Yawatanishi-ku, Kitakyushu-shi, Fukuoka F-term in the Cement Development Center of Mitsubishi Materials Corporation 4D067 DD03 DD08 DD09 DD13 DD14 EE18 EE32 EE50 GA06 GB03 GB10

Claims (4)

[Claims] 1. A cylindrical main body which is vertically erected and into which solid matter such as concrete waste material is charged from above, and which is rotatably disposed inside the main body and stirs the solid matter. A vertical milling device having a rotatable table feeder disposed at a predetermined interval between the member and the lower end of the main body, and for discharging the solid material that has been ground, An aggregate recovery system comprising: a classifying means for classifying solid matter into coarse aggregates and fine aggregates; and a fine powder discharging means for supplying air to the inside of the main body from below and discharging fine powder from above. . 2. The aggregate recovery system according to claim 1, wherein said solid material such as said concrete waste material is heated. 3. A cylindrical main body which is vertically erected and into which solids such as concrete waste material are loaded from above, and which is rotatably disposed inside the main body and stirs the solids. A vertical milling device having a rotatable table feeder disposed at a predetermined interval between the member and the lower end of the main body, and for discharging the solid material that has been ground, An aggregate recovery system comprising: a classifying means for classifying solid matter into coarse aggregate and fine aggregate; and a fine powder discharging means for supplying hot air to the inside of the main body from below and discharging fine powder from above. . 4. The aggregate recovery system according to claim 1, wherein said vertical milling device has a surfactant supply means for supplying a surfactant into said main body.