JP5145253B2 - Roadbed material manufacturing method and roadbed material manufacturing apparatus - Google Patents

Description

  The present invention relates to a method for manufacturing a roadbed material used for a roadbed material and an apparatus for manufacturing the roadbed material.

  Concrete blocks generated by building demolition etc. are crushed and reused as roadbed materials. At this time, it is a problem that the roadbed material contains hexavalent chromium harmful to the human body. Normally, a concrete block is crushed and contains hexavalent chromium several times the allowable amount stipulated by law. Then, the processing agent for detoxifying this hexavalent chromium was developed, and the processing method of a concrete lump etc. is developed (refer patent document 1) (refer patent document 2) (refer patent document 3).

JP 2005-95809 A JP 2007-14881 A JP 2007-301421 A

When the concrete block is crushed and reused as roadbed material, a detoxifying agent is mixed in the pulverizer. For example, if an aqueous solution of a detoxification treatment agent as described in Patent Document 2 is mixed by about 0.2% by weight, detoxification treatment is possible. However, it is not easy to add a small amount of a detoxifying agent solution of about 1/1000 in weight ratio to powdered concrete and mix it uniformly. Since the detoxification treatment solution is expensive, excessive use leads to an increase in cost. On the other hand, when the addition amount is partially insufficient, there arises a problem that the environmental standard is not satisfied. Moreover, it is not easy to determine whether or not they are mixed uniformly. A complex and expensive agitation reaction at the production site of roadbed materials, such as crushing concrete blocks brought in from the site of building demolition work, placing them in the stockyard, and transporting them to the site of road construction etc. in a timely manner It is not realistic to install equipment.
In order to solve the above-mentioned problems, the present invention uses a relatively simple facility to reliably and uniformly mix a detoxification agent solution into powdered concrete, thereby producing a roadbed material optimal for roadbed construction. It is an object to provide a method and an apparatus for manufacturing a roadbed material.

The following configurations are means for solving the above-described problems.
<Configuration 1>
In order to detoxify the hexavalent chrome contained in the concrete powder, a pulverization apparatus for pulverizing the concrete lump to obtain concrete powder to be used for roadbed materials, a conveyor for conveying the concrete powder from the pulverization apparatus to a stock yard, and The detoxification treatment agent solution supplied from the tank toward the concrete powder falling in a band shape from the end of the conveyor to the stock yard is stored An apparatus for manufacturing a roadbed material, comprising: a spraying device that sprays in a mist form.

<Configuration 2>
In the roadbed material manufacturing apparatus according to Configuration 1, in the spraying device, the detoxification treatment agent solution is atomized separately at least toward the front and back surfaces of the concrete powder falling in the belt shape. An apparatus for producing a roadbed material, characterized in that a nozzle for jetting is provided.

<Configuration 3>
In the roadbed material manufacturing apparatus according to Configuration 1 or 2, the flow of the concrete powder is partially or entirely prevented from preventing natural fall of the concrete powder falling in a band shape from the end of the conveyor to the stockyard. And a spraying device for spraying the detoxifying agent solution supplied from the tank in a mist toward the concrete powder while preventing the hood from scattering. Roadbed material manufacturing equipment.

<Configuration 4>
The roadbed material manufacturing apparatus according to Configuration 3, wherein the hood is supported and fixed near the end of the conveyor, and the nozzle is fixed to the hood.

<Configuration 5>
Included in the concrete powder is a step of pulverizing a concrete lump by a pulverizer to obtain concrete powder to be used for a roadbed material, a step of conveying the concrete powder from the pulverizer to a stock yard by a conveyor, and a tank. A step of accumulating a detoxifying agent solution having a predetermined concentration for detoxifying hexavalent chromium, and the concrete powder falling in a strip shape from the end of the conveyor to the stock yard by a spraying device, A method for producing a roadbed material, comprising a step of spraying the detoxifying agent solution supplied from a tank in a mist toward the concrete powder.

<Configuration 6>
In the method for manufacturing a roadbed material according to Configuration 5 , the flow of the concrete powder is partially or wholly prevented by the hood from preventing natural fall of the concrete powder falling in a strip shape from the end of the conveyor to the stockyard. The detoxification treatment agent solution supplied from the tank is sprayed in a mist toward the concrete powder while being prevented from scattering by the hood with a spray device in a state of being enclosed A manufacturing method of roadbed material.

<Effect of Configuration 1>
Since the detoxification agent solution is sprayed in the form of mist onto the dry concrete powder that is transported from the crusher to the stockyard by the conveyor and falls into a strip shape, a small amount of the detoxification agent solution is uniformly attached to the concrete powder. be able to. In addition, since the sprayed detoxification solution falls onto the concrete powder that has already been dropped and stacked, it is possible to mix the detoxification solution with a minimum and sufficient amount of the detoxification solution without any waste. it can. Therefore, all the concrete powder is automatically detoxified uniformly on the stock yard without subsequent processing such as stirring. Furthermore, there is an effect that the humidification treatment necessary for the roadbed material can be performed at the same time.
<Effect of Configuration 2>
When the detoxification treatment solution is sprayed in two directions or a plurality of directions on the dried concrete powder falling in a belt shape in a mist form, the detoxification treatment solution adheres uniformly to the entire concrete powder.
<Effect of Configuration 3>
When spraying the detoxification solution toward the concrete powder in the form of a mist, if a hood is provided that partially or wholly surrounds the flow of the concrete powder without hindering the natural fall of the concrete powder, It can be made to adhere to concrete powder, without scattering the detoxification solution.
<Effect of Configuration 4>
By fixing the hood near the end of the conveyor and fixing the nozzle to this hood, a device that uniformly mixes the detoxifying agent solution and the concrete powder can be realized without complicated and expensive equipment as a whole. it can.

It is the schematic which shows the whole structure of the manufacturing apparatus of the roadbed material of Example 1. FIG. It is explanatory drawing of the concrete powder. 4 is a perspective view showing a specific example of a main part of the spray device 18. FIG. It is explanatory drawing of the density | concentration adjustment method of the detoxification processing agent. It is explanatory drawing which shows the Example of the spraying apparatus.

    Hereinafter, embodiments of the present invention will be described in detail for each example.

FIG. 1 is a schematic diagram illustrating an overall configuration of a roadbed material manufacturing apparatus according to a first embodiment.
The roadbed material manufacturing apparatus 10 shown in the figure includes a crushing device 12, a conveyor 14, a tank 16, and a spraying device 18, and manufactures a roadbed material 24. The crushing device 12 is a device that crushes the concrete lump 20 to obtain concrete powder 22 used for the roadbed material 24. The conveyor 14 is a device for conveying the concrete powder 22 from the crushing device 12 to the stock yard 26. The tank 16 is an apparatus for accumulating a detoxifying agent solution 28 having a predetermined concentration for detoxifying hexavalent chromium contained in the concrete powder 22.

  In this embodiment, the spray device 18 includes a hood 30 and a nozzle 32. The concrete powder 22 is conveyed by the conveyor 14 and falls in a strip shape from the end of the conveyor 14 to the stock yard 26. The spraying device 18 is a device for pumping out the detoxifying agent solution supplied from the tank 16 by the pump 34 and spraying it in a mist toward the concrete powder 22 by the nozzle 32 connected to one end of the hose 36.

FIG. 2 is an explanatory diagram of the concrete powder 22.
Details of each part of the above-mentioned roadbed material manufacturing apparatus 10 will be described with reference to FIG. The concrete block 20 shown in FIG. 2 is brought in from a site such as a building demolition work. This is pulverized using the pulverizer 12. Using a sieve (not shown) inside the pulverizer 12 or in the vicinity of the discharge port 13, the concrete powder 22 is made to have a particle size of a predetermined value or less. As the roadbed material, a large amount of a material pulverized to a particle size of 10 mm or less is used. This roadbed material has a standard called [RC10-0], and the allowable residual content of hexavalent chromium is strictly limited to 0.05 mg or less per liter.

  Therefore, in the present invention, the detoxification treatment agent solution 28 is sprayed on the concrete powder 22 that is being transported by the conveyor 14 and dropped from the end of the conveyor 14 to the stock yard 26, thereby detoxifying the concrete powder. Specifically, for example, hexavalent chromium is reduced to trivalent chromium in the manner shown in Patent Document 1. The kind of the detoxifying treatment solution 28 is arbitrary. The stock yard 26 is a place for storing the dehumidified and humidified concrete powder 22 before shipment, and may not have a container. It does n’t matter if it ’s outdoors. The conveyor 14 is an endless belt device having a known structure for conveying the finely divided concrete powder 22 and dropping it into the stock yard 26.

  As shown in FIG. 1, when the detoxifying agent solution is sprayed onto the dried concrete powder 22 falling from the end of the conveyor 14 in the form of a mist in the spraying device 18, a small amount of the detoxifying agent solution is uniformly distributed. It can be attached to the concrete powder 22. That is, even if the detoxifying agent solution is sprinkled on the roadbed material 24 like a shower and stirred, it is not easy to uniformly penetrate a very small amount of the detoxifying agent solution into the entire amount of the roadbed material. In particular, this type of roadbed material manufacturing factory has many equipment that crushes concrete blocks brought in by trucks, etc., and a scale that piles up the crushed concrete powder in a stock yard. Equipment that is accurately weighed and sprinkled on the piled concrete powder and stirred well is not suitable.

  Even if the detoxification agent solution is sprinkled on the piled concrete powder and stirred with a power shovel, etc., there is a loss of excessive use of the detoxification agent solution or letting it soak into the ground. May occur in large quantities. The roadbed material manufacturing apparatus 10 of the present invention can automatically attach an appropriate amount of a mist-like detoxifying agent solution to almost all concrete powder 22. In addition, since the sprayed detoxification treatment solution, whether or not attached to the concrete powder 22, almost falls naturally onto the concrete powder 22 that has already been dropped and piled up. The whole amount is mixed into the concrete powder 22. That is, a necessary and sufficient minimum amount of the detoxifying agent solution can be mixed into the concrete powder 22 without waste. Moreover, all the concrete powder 22 is automatically and uniformly rendered harmless on the stock yard 26 without subsequent processing such as stirring.

  Moreover, normally, when the pulverized concrete powder 22 is dropped on the stock yard 26, dust is generated. In the apparatus of the present invention, the spraying device 18 is used to humidify the concrete powder 22 while detoxifying the concrete powder 22, so that there is an effect that dust is not generated. Further, even if it is subsequently scattered by wind or the like, it does not pollute the environment because it is after detoxification treatment. In general, the roadbed material 24 is pressed using a roller or the like after laying at a construction site. At this time, tightening is better if it contains a little water. Therefore, watering the roadbed material 24 in advance has been performed. In the past, this amount of watering was sometimes excessive or insufficient. However, for example, if the spraying device 18 is sufficiently humidified, or if a spraying shower head or the like is provided at the lower end of the spraying device 18, there is an effect that an appropriate amount of humidification can be simultaneously applied to the entire concrete powder 22.

FIG. 3 is a perspective view showing a specific example of the main part of the spraying device 18.
As shown in this figure, the concrete powder 22 falls in a band shape from the end of the conveyor 14. At this time, the concrete powder 22 falls so as to spread a little apart as a whole. The concrete powder 22 sifted in the previous process falls like a powder rain. A detoxifying agent solution 28 is sprayed toward the concrete powder 22 using a nozzle 32 in the form of a mist. It is advisable to adjust the outlet of the nozzle 32 so that the mist spreads in the width direction (arrow A direction) of the concrete powder 22 and does not spread much in the vertical direction (arrow B direction). Also, a plurality of nozzles 32 may be provided and arranged in a plurality of directions so that the mist-like detoxifying agent solution 28 contacts the concrete powder 22 evenly. In the embodiment of FIG. 3, nozzles 32 for spraying the detoxification treatment solution 28 in a mist form are provided separately toward the front and back surfaces of the band where the concrete powder 22 falls.

FIG. 4 is an explanatory diagram of a method for adjusting the concentration of the detoxifying agent 40.
The detoxification treatment agent 40 is weighed in advance to make a stock solution of the detoxification treatment agent solution 28 and stored in the preparation container 42. This blending container 42 is brought into a roadbed material manufacturing factory. The tank 16 stores the detoxification solution 28 for about one day. First, a predetermined amount of tap water or the like is stored in the tank 16. Then, before starting the operation, the stock solution in the preparation container 42 is put into the tank 16 to mix the harmless treatment solution 28 having a predetermined concentration. In this way, it is possible to prepare the detoxification treatment agent solution 28 having an appropriate concentration without any errors in field work.

  For example, when mixing concrete powder 22 and a large amount of water, a shower sprinkler may be used. However, in the apparatus of the present invention, since a small amount of the detoxifying agent solution 28 is continuously adhered to the concrete powder 22 that is continuously produced, the spraying device 18 that atomizes the detoxifying agent solution 28 is provided. . In an actual example, 10 cubic meters of the detoxifying solution 28 is prepared for an equipment that manufactures 100 tons of roadbed material per day. It suffices if the tank 16 can accommodate such a detoxifying solution 28. For example, the concentration of the detoxifying agent solution 28 is adjusted so that the detoxifying agent described in Patent Document 1 is mixed by 0.1 to 0.2% by weight with respect to the cement. Assuming that the roadbed material manufacturing apparatus is operated for 5 hours per day, spraying is performed every 2 cubic meters per hour. Thus, the optimum amount of the detoxifying agent solution 28 for detoxifying the concrete powder 22 can be continuously supplied.

FIG. 5 is an explanatory view showing an embodiment of the spray device 18.
Fig.5 (a) shows the side view of the nozzle 32 which sprays the concrete powder 22 falling vertically, and the detoxification agent solution 28 from the side. As shown in the figure, the nozzle 32 injects and sprays the detoxifying agent solution 28 so as to be relatively less spread when viewed in the vertical direction. On the other hand, FIG. 5B shows a cross section of the concrete powder 22 that falls vertically and a top view of the nozzle 32 that sprays the detoxifying solution 28 from the side thereof. In this way, the detoxifying agent solution 28 is sprayed at a wide angle so that it spreads over the width of the concrete powder 22 when viewed from above, and a flow of mist particles toward all the concrete powder 22 is created. Good.

  The mist is light and easy to scatter. Moreover, it does not return after passing through the portion of the concrete powder 22. Therefore, scattering was prevented by the half hood 31 shown in FIG. With this structure, even if only one nozzle 32 is provided, the mist-like detoxifying agent solution 28 can be retained around the concrete powder 22. On the other hand, the hood 30 shown in FIG. 5D entirely surrounds the flow of the concrete powder 22 without hindering the natural fall of the concrete powder 22 falling in a band shape. A pair of nozzles 32 are opposed to each other in the hood 30 and the concrete powder 22 falls between them. Thereby, for example, neither the concrete powder 22 nor the detoxifying agent solution 28 is scattered by the wind or the like, and both are mixed at an appropriate ratio.

  In such a spraying apparatus, a considerable portion of the sprayed detoxification solution 28 adheres to the concrete powder 22, but the rest becomes water droplets 29 and adheres to the inner wall of the hood 30. However, the detoxifying agent solution 28 attached to the inner wall of the hood 30 is dripped onto the concrete powder 22 that has already been discharged by gravity. Therefore, the ratio of the weight of the concrete powder 22 dropped from the conveyor 14 to the stock yard 26 and the weight of the detoxifying agent solution 28 sprayed into the hood 30 is controlled so as to be an optimum value necessary for the detoxification treatment. For example, the concrete powder 22 discharged to the stock yard 26 continues to be supplied with the detoxification treatment solution 28 necessary and sufficient for the detoxification treatment.

  As shown in FIGS. 5D and 1, the hood 30 is supported and fixed by a frame 38 near the end of the conveyor 14, and the nozzle 32 is fixed to the hood 30. In this way, the detoxifying agent solution 28 is sprayed and adhered to the concrete powder 22 falling through the hood 30 supported and fixed in the vicinity of the end of the conveyor 14 by using a nozzle inside the hood 30. By adopting such a structure, an apparatus for uniformly mixing the detoxification solution 28 and the concrete powder 22 can be realized without complicated and expensive equipment as a whole.

DESCRIPTION OF SYMBOLS 10 Subbase material manufacturing apparatus 12 Crushing apparatus 13 Discharge port 14 Conveyor 16 Tank 18 Spraying apparatus 20 Concrete lump 22 Concrete powder 24 Subbase material 26 Stockyard 28 Detoxification agent solution 29 Water drop 30 Hood 31 Half food 32 Nozzle 34 Pump 36 Hose 38 frame 40 detoxification agent 42 compounding container

Claims (6)

A crushing device for crushing concrete blocks to obtain concrete powder for use in roadbed materials;
A conveyor for conveying the concrete powder from the crusher to a stock yard;
A tank that accumulates a detoxifying agent solution having a predetermined concentration for detoxifying hexavalent chromium contained in the concrete powder;
A roadbed comprising: a spraying device for spraying the detoxifying agent solution supplied from the tank in a mist toward the concrete powder falling in a band shape from the end of the conveyor to the stockyard. Material manufacturing equipment. In the manufacturing apparatus of the roadbed material according to claim 1,
A roadbed characterized in that the spraying device is provided with a nozzle for spraying the detoxifying agent solution in a mist form separately toward at least the front and back surfaces of the concrete powder falling in the band shape. Material manufacturing equipment. In the manufacturing device of the roadbed material according to claim 1 or 2,
A hood that partially or wholly surrounds the flow of the concrete powder without hindering the natural fall of the concrete powder falling into the stock yard from the end of the conveyor,
An apparatus for producing a roadbed material, comprising: a spraying device that sprays the detoxifying agent solution supplied from the tank in a mist toward the concrete powder while preventing scattering by the hood. In the manufacturing device of the roadbed material according to claim 3,
The hood is supported and fixed near the end of the conveyor, and the nozzle is fixed to the hood. Crushing concrete lump with a crushing device to obtain concrete powder to be used for roadbed material,
A step of conveying the concrete powder from the pulverizer to a stockyard by a conveyor;
A step of accumulating a detoxifying solution of a predetermined concentration for detoxifying hexavalent chromium contained in the concrete powder in a tank;
A step of spraying the detoxifying agent solution supplied from the tank toward the concrete powder in a mist form by a spraying device with respect to the concrete powder falling in a band shape from the end of the conveyor to the stock yard. A method for manufacturing a roadbed material, comprising: In the manufacturing method of the roadbed material according to claim 5 ,
Without hindering the natural fall of the concrete powder falling into the stock yard from the end of the conveyor by the hood, in a state of surrounding the flow of the concrete powder partially or entirely,
A method for producing a roadbed material comprising a step of spraying the detoxifying agent solution supplied from the tank by a spray device in a mist toward the concrete powder while preventing scattering by the hood. .

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