Concrete manufacturing system and concrete manufacturing method

Abstract

To cool a fine aggregate by a simple cooling structure, and to reduce a cost for a cooling facility.SOLUTION: A concrete production system comprises: a wet type classifier 3 fed with a fine aggregate S1 pulverized by a rod mill 2 and raking up a fine aggregate S2 so as to be stirred together with cooling water W at the inside; a chiller 4 feeding the cooling water W to the classifier 3; a storage facility 5 storing cooled sand S3 obtained by cooling the fine aggregate S2 by the classifier 3; a cooling control unit 6 detecting the temperature of the cooled sand S3 stored in the storage facility 5 to control the temperature of the cooled sand S3 based on at least one of a first feed condition for the cooling water W fed by the chiller 4 and a second feed condition for the fine aggregate S2 in the classifier 3; and a mixer mixing the cooled sand S3 stored in the storage facility 5 with cement to produce concrete.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a concrete manufacturing system and a concrete manufacturing method.

Background Art

[0002] Conventionally, in the case of a dam made of ultra-high performance concrete, the control of the placing temperature of concrete has been a very important issue directly related to the control of temperature cracking. At present, for example, as shown in Patent Document 1, various measures for reducing the temperature of the kneaded concrete have been taken. As a general construction method for reducing temperature, the precooling method is known. Such a precooling method is a method of cooling the materials of concrete before kneading and lowering the temperature of the whole concrete. Among them, it is effective to cool the aggregate having the largest total heat capacity, and in the case of coarse aggregate, since the cold air cooling equipment has become inexpensive, it has come to be used everywhere.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, the following problems have existed in the temperature control of aggregate in conventional concrete production. That is, since the fine aggregate becomes dense with small gaps when stacked, the effect of external cooling is limited to the surface layer range and it is difficult to cool. As methods for cooling fine aggregate, there are a sand precooling method in which fine aggregate is cooled with liquid nitrogen before mixing, and a water immersion cooling and dehydration method for fine aggregate that is immediately used for mixing by immersing the fine aggregate in cooling water and stabilizing the surface water content by vibration centrifugal dehydration. However, both methods require the use of dedicated special equipment, which has the problem of high costs, and there is room for improvement in this regard.

[0005] The present invention has been made in view of the above-described problems, and an object thereof is to provide a concrete manufacturing system and a concrete manufacturing method that can cool fine aggregate with a simple cooling structure and reduce the cost of cooling equipment.

Means for Solving the Problems

[0006] To achieve the above object, a concrete manufacturing system according to the present invention is a concrete manufacturing system including a crusher for manufacturing fine aggregate used in concrete, wherein the fine aggregate crushed by the crusher is supplied, a wet classifier that scrapes up and stirs the fine aggregate together with internal cooling water, a cooling water supply device that supplies cooling water to the classifier, a storage facility that stores the cooled sand obtained by cooling the fine aggregate in the classifier, a cooling control unit that detects the temperature of the cooled sand stored in the storage facility and controls the temperature of the cooled sand based on at least one of a first supply condition of the cooling water supplied by the cooling water supply device and a second supply condition of the fine aggregate in the classifier, and a mixer that mixes the cooled sand stored in the storage facility with cement to manufacture concrete.

[0007] Further, the concrete manufacturing method according to the present invention is a concrete manufacturing method manufactured using the above-described concrete manufacturing system, and includes a step of supplying the fine aggregate crushed by the crusher to the classifier, a step of supplying cooling water to the classifier by the cooling water supply device, and scraping and stirring the fine aggregate in the classifier together with the cooling water, and a step of moving and storing the cooled sand, in which the fine aggregate is cooled by the classifier, to the storage facility, and a step of manufacturing concrete by charging the cooled sand stored in the storage facility into the mixer and mixing it with cement. In the cooling control unit, the cooling sand temperature of the cooled sand stored in the storage facility is detected, and the temperature of the cooled sand is controlled based on at least one of the first supply condition and the second supply condition.

[0008] In the present invention, by supplying the cooling water cooled by the cooling water supply device to the classifier, the fine aggregate manufactured by the crusher and charged into the classifier can be cooled by being scraped and stirred together with the cooling water to obtain cooled sand. Then, the cooled sand can be stored in the storage facility, for example, for about 5 days without temperature fluctuation. Further, in the present invention, in the cooling control unit, the cooling sand temperature of the cooled sand stored in the storage facility is detected, and the temperature of the cooled sand can be controlled based on at least one of the first supply condition of the cooling water supplied by the cooling water supply device and the second supply condition of the fine aggregate in the classifier, so that the optimum cooling sand temperature can be maintained. Thus, in the present invention, since the fine aggregate can be cooled by a simple cooling structure in which only the cooling water supply device is provided in the classifier, the cost of the cooling facility can be reduced.

[0009] Further, in the concrete manufacturing system according to the present invention, the classifier includes a water tank into which the fine aggregate crushed by the crusher is charged, the aforesaidA water spraying device that sprays the cooling water cooled by the cooling water supply device at the discharge port of the cooling sand, and the water tank is characterized in that the cooling water sprayed by the water spraying device is fed into the water tank and stored therein.

[0010] In this case, since the cooling water cooled by the cooling water supply device is sprayed by the water spraying device at the discharge port of the cooling sand classified by the classifier, clogging of the discharge port can be prevented. Furthermore, by sending the sprayed cooling water to the water tank and storing it, the fine aggregate introduced into the water tank can be stirred together with the cooling water during washing and classification, so that the fine aggregate can be efficiently cooled.

Effect of the Invention

[0011] According to the concrete manufacturing system and the concrete manufacturing method of the present invention, fine aggregate can be cooled by a simple cooling structure, and the cost of cooling equipment can be reduced.

Brief Description of the Drawings

[0012]

Figure 1

Figure 2

Embodiments for Carrying Out the Invention

[0013] Hereinafter, a concrete manufacturing system and a concrete manufacturing method according to an embodiment of the present invention will be described with reference to the drawings.

[0014] As shown in FIGS. 1 and 2, the concrete manufacturing system 1 according to the present embodiment includes a rod mill 2 (grinder) that manufactures fine aggregate used in concrete, and a wet classifier 3 that scrapes up and stirs the fine aggregate S1 pulverized by the rod mill 2 together with the internal cooling water W.

[0015] Furthermore, as shown in FIG. 2, the concrete manufacturing system 1 includes a chiller 4 (cooling water supply device) that supplies cooling water W to the classifier 3, a storage facility 5 that stores the cooled sand S3 in which the fine aggregate S2 is classified and washed and cooled in the classifier 3, a cooling control unit 6 that controls the cooling temperature of the cooled sand S3 to a predetermined temperature, and a mixer 7 that mixes the cooled sand S3 stored in the storage facility 5 with cement to produce concrete.

[0016] Here, in the present embodiment, reference numeral S1 indicates the fine aggregate when crushed by the rod mill 2, reference numeral S2 indicates the fine aggregate that is introduced into the classifier 3 and cooled together with the cooling water W, and reference numeral S3 indicates the fine aggregate (i.e., cooled sand) that is taken out from the classifier 3 and stored in the storage facility 5.

[0017] The classifier 3 is connected to the rod mill 2 and the chiller 4. The classifier 3 applies a rotational force to the fine aggregate S2 introduced from the rod mill 2, washes it with water (cooling water W), and classifies it into the cooled sand S3. The classifier 3 includes a water tank 31, a washing and classifying device 32, and a vibrating water draining device 33.

[0018] The water tank 31 is supplied with the fine aggregate S1 crushed by the rod mill 2. The water tank 31 is connected to a cooling water recovery section 35 (described later) provided in the vibrating water draining device 33, and the cooling water W discharged by the vibrating water draining device 33 flows in and is stored in the tank. The overflow water of the water tank 31 is sent to the turbid water treatment facility 8 connected to the water tank 31 for turbid water treatment.

[0019] The washing and classifying device 32 includes a rotating blade (not shown) that scrapes up and stirs the cooling water W in the water tank 31 and the fine aggregate S2 introduced from the rod mill 2, washes the fine aggregate S2, and classifies it into the cooled sand S3. The rotating blade is disposed in the water tank 31.

[0020] The vibration water drainage device 33 is arranged on the downstream side of the cleaning and classification device 32, and removes and discharges the water of the cooled sand S3 classified and carried out by the cleaning and classification device 32 by vibration. In order to prevent clogging of the water discharge part of the cooled sand S3, the vibration water drainage device 33 is provided with a water spraying device 34 that sprays cooling water W cooled by the chiller 4 onto the water discharge part thereof. The cooling water W sprayed from the water spraying device 34 is recovered by a cooling water recovery part 35 provided at the lower part of the vibration water drainage device 33. The cooling water recovery part 35 is connected to the water tank 31 by a pipe. The cooling water W recovered by the cooling water recovery part 35 is sent to the water tank 31 and stored. That is, the cooling water W supplied from the chiller 4 is stored in the water tank 31.

[0021] The chiller 4 is connected to the water spraying device 34 of the classifier 3. The cooling water W cooled by the chiller 4 is sent to the water spraying device 34 and sprayed toward the water discharge part of the vibration water drainage device 33. In this embodiment, the temperature of the cooling water W cooled by the chiller 4 is controlled by the cooling control part 6.

[0022] The cooling control part 6 detects the temperature of the cooled sand S3 stored in the storage facility 5, and controls the temperature (cooled sand temperature) of the cooled sand S3 based on at least one of the first supply condition of the cooling water W supplied by the chiller 4 and the second supply condition of the fine aggregate S2 in the classifier 3.

[0023] As the first supply condition, for example, it is the temperature of the cooling water W cooled by the chiller 4. In this case, when it is desired to lower the cooled sand temperature, it is controlled to lower the cooling temperature of the cooling water W cooled by the chiller 4.

[0024] As the second supply condition, for example, it is the amount of the fine aggregate S2 in the classifier 3. In this case, when it is desired to lower the cooled sand temperature, it is controlled to reduce the input amount of the fine aggregate S2 input into the classifier 3.

[0025] The fine aggregate (cooling sand S3) stored in the storage facility 5 has small gaps and is dense when stored, so there is little heat exchange with the outside. Therefore, in the concrete manufacturing system 1 of the present embodiment, when the fine aggregate S2 manufactured by the rod mill 2 is stirred with water in the crusher 3, the temperature of the fine aggregate S1 whose water temperature in the crusher 3 is almost the same as the outside air temperature hardly fluctuates during storage for at least about 4 to 5 days. Therefore, by using the cooling water W cooled by the chiller 4 in the water when the crusher 3 scoops up, the fine aggregate S2 is cooled and stored in the storage facility 5 at that temperature.

[0026] As shown in FIG. 2, as a concrete manufacturing method using the above-described concrete manufacturing system 1, first, the fine aggregate S1 manufactured by the rod mill 2 from the raw materials is put into the water tank 31 of the crusher 3. Next, the fine aggregate S2 is scooped up and stirred together with the cooling water W in the water tank 31 in the washing and classification device 32.

[0027] Thereafter, the cooling sand S3 in which the fine aggregate S2 is classified and cooled by the crusher 3 is taken out after draining the water with the vibrating water draining device 33 and moved to the storage facility 5 for storage. At this time, the cooling water W cooled by the chiller 4 is sprinkled by the sprinkler device 34 at the water discharge part. Then, the sprinkled cooling water W is recovered by the cooling water recovery part 35 and sent to the water tank 31. Next, the cooling sand S3 stored in the storage facility 5 is put into the mixer 7 and mixed with cement to manufacture concrete.

[0028] Next, the operation of the above-described concrete manufacturing system 1 and concrete manufacturing method will be described in detail with reference to the drawings. In this embodiment, as shown in FIG. 2, by supplying the cooling water W cooled by the chiller 4 to the crusher 3, the fine aggregate S2 produced by the rod mill 2 and introduced into the crusher 3 can be cooled by being scraped up and stirred together with the cooling water W to obtain cooled sand S3. Then, the cooled sand S3 can be stored in the storage facility 5 for about 5 days, for example, in a state where the temperature does not fluctuate.

[0029] Further, in this embodiment, in the cooling control unit 6, the temperature of the cooled sand S3 stored in the storage facility 5 is detected, and the temperature of the cooled sand S3 can be controlled based on at least one of the first supply condition of the cooling water W supplied by the chiller 4 and the second supply condition of the fine aggregate S2 in the crusher 3, so that the optimal cooled sand temperature can be maintained. Thus, in this embodiment, since the fine aggregate S2 can be cooled by a simple cooling structure in which the chiller 4 is provided in the crusher 3, the cost of the cooling equipment can be reduced.

[0030] Also, in this embodiment, the cooling water W cooled by the chiller 4 is sprinkled by the sprinkler device 34 at the discharge port of the cooled sand S3 classified by the crusher 3, so that clogging of the discharge port can be prevented. Further, by sending the sprinkled cooling water W to the water tank 31 for water storage, the fine aggregate S2 introduced into the water tank can be stirred together with the cooling water W during washing and classification, so that the fine aggregate S2 can be efficiently cooled.

[0031] Moreover, in this embodiment, since the cooled sand S3 stored in the storage facility 5 is introduced into the mixer 7 within 5 days from the start of storage and mixed with the cement, the cooled sand S3 can be mixed with the cement in the mixer 7 in a state where the temperature does not fluctuate, so that concrete with stable quality can be produced.

[0032] Also, when fine aggregate S1 is continuously fed from the rod mill 2 into the crusher 3, since the cooling water W is maintained in a state of accumulating in the crusher 3, the use of the cooling water W can also be minimized.

[0033] For example, in the case of fine aggregate cooled by the above method at the dam site, as an example of the result of temperature control of cooled sand in summer, it was possible to maintain the temperature at about 23°C with respect to the temperature of fine aggregate which is usually 30°C. For example, as an actual example, it was possible to maintain cooled sand at 23°C by spraying 15°C cooling water from a sprinkler at a water volume of 100 L / min. And due to the decrease in the temperature of the fine aggregate (cooled sand), the temperature of the freshly mixed concrete can be reduced by 2 to 3°C.

[0034] Also, as the cost for cooling the fine aggregate, for example, in dam construction by the rationalized construction method (RCD method) of a concrete dam, when the concrete to be placed in three months in summer is 250,000 m 3 When taken as such, compared with the cost required to lower the concrete temperature from 24°C to 22°C by the sand precooling method, when using the concrete manufacturing system 1 according to the present embodiment, it can be suppressed to 1 / 100 or less. That is, in the concrete manufacturing system 1 according to the present embodiment, since only the cost of installing the chiller 4 and the electricity cost are required, it is an excellent method that can lower the concrete temperature at low cost.

[0035] As described above, in the concrete manufacturing system and the concrete manufacturing method according to the present embodiment, the fine aggregate can be cooled by a simple cooling structure in which the chiller 4 is provided in the crusher 3, and the cost for the cooling equipment can be reduced.

[0036] As described above, embodiments of the concrete manufacturing system and the concrete manufacturing method according to the present invention have been described, but the present invention is not limited to the above embodiments and can be appropriately changed without departing from the gist thereof.

[0037] For example, in the above-described embodiment, the cooling water W cooled by the chiller 4 is sprayed from the water spraying device 34 of the crusher 3, and the cooling water W is recovered by the cooling water recovery unit 35 and introduced into the water tank 31. However, the present invention is not limited to this configuration. For example, the cooling water W may be directly supplied from the chiller 4 to the water tank 31, or the cooling water W may be supplied from a part of the cleaning and classification device 32.

[0038] Also, in the present embodiment, the chiller 4 is adopted as the cooling water supply device. However, the present invention is not limited to the chiller 4, and any device or equipment that can cool the predetermined cooling water W is not particularly limited.

[0039] In addition, in the present embodiment, the rod mill 2 is adopted as the crusher, but the present invention is not limited thereto, and other types of crushers can also be adopted.

[0040] In addition, within the scope not departing from the gist of the present invention, it is possible to appropriately replace the components in the above-described embodiment with well-known components.

Explanation of Reference Numerals

[0041] 1 Concrete manufacturing system 2 Rod mill (crusher) 3 Crusher 4 Chiller (cooling water supply device) 5 Storage facility 6 Cooling control unit 7 Mixer 8 Turbid water treatment device 31 Water tank 32 Cleaning and classification device 33 Vibration water draining device S1, S2 Fine aggregate S3 Cooling sand

Claims

1. A concrete manufacturing system comprising a crusher for manufacturing fine aggregate used in concrete, a wet classifier that supplies fine aggregate crushed by the crusher and agitates the fine aggregate by lifting it together with internal cooling water, a cooling water supply device that supplies cooling water to the classifier, a storage facility that stores cooled sand obtained by cooling the fine aggregate with the classifier, a cooling control unit that detects the temperature of the cooled sand stored in the storage facility and controls the temperature of the cooled sand based on at least one of a first supply condition of the cooling water supplied by the cooling water supply device and a second supply condition of the fine aggregate in the classifier, and a mixer that manufactures concrete by mixing the cooled sand stored in the storage facility with cement. A concrete manufacturing system characterized by comprising these components.

2. The classifier includes a water tank into which the fine aggregate crushed by the crusher is introduced, and a water spraying device that sprays the cooling water cooled by the cooling water supply device at the discharge port of the cooled sand. The concrete manufacturing system according to claim 1, characterized in that the cooling water sprayed by the water spraying device is fed into the water tank and stored therein.

3. A concrete manufacturing method manufactured using the concrete manufacturing system according to claim 1 or 2, a step of supplying the fine aggregate crushed by the crusher to the classifier, a step of supplying cooling water to the classifier by the cooling water supply device and agitating the fine aggregate in the classifier by lifting it together with the cooling water, a step of moving and storing the cooled sand obtained by cooling the fine aggregate with the classifier to the storage facility, a step of manufacturing concrete by putting the cooled sand stored in the storage facility into the mixer and mixing it with cement, having, In the cooling control unit, the temperature of the cooled sand stored in the storage facility is detected, and the temperature of the cooled sand is controlled based on at least one of the first supply condition and the second supply condition. A concrete manufacturing method characterized by this.

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