JP2002336725A - Milling method and milling plant - Google Patents

Abstract

PROBLEM TO BE SOLVED: To manufacture sand having an almost spherical shape and a uniform particle size and comprising a properly mixed composition consisting of sand particles having a relatively large particle size and sand particles having a relatively small particle size. SOLUTION: In a milling method and a milling plant for manufacturing sand, sand particles having the relatively small particle size are bonded to the peripheries of sand particles having the relatively large particle size by allowing sand particles to absorb water and imparting mutual adhesion force to sand particles by moisture between sand particles by a dry grinding/ classifying process for grinding and classifying a raw material by a grinder/ classifier 4 and a wet mixing process for mixing ground and classified sand with water by a wet mixer 6.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a milling method and a milling plant apparatus, and more particularly to a sand milling method for grinding sand and producing sand having a uniform particle size suitable for concrete and a sand milling plant apparatus. is there.

[0002]

2. Description of the Related Art When building buildings, bridges, tunnels, and other various structures, concrete is indispensable.
Although the demand for concrete sand continues to increase, natural sands (river sand, sea sand, etc.) are scarce in Japan,
In particular, recently, from the viewpoints of nature protection and marine resource protection, most local governments prohibit sand extraction from natural sands. Used by blending with sand.

As a sand-making apparatus of this kind, the present applicant has already disclosed Japanese Patent Publication No. 47-11029 and Japanese Patent Publication No. 56-91.
No. 34, No. 58-21542, No. 5
Various types disclosed in JP-A-9-24363, JP-B-60-118, JP-B-2-46259, and Japanese Patent No. 2664045 are provided.

[0004] These sand making devices have advantages over similar devices in the past, but when used as concrete sand, higher quality sand is required.
According to the JIS A 5005 “crushed sand for concrete” standard, when sand produced by a sand making device is used as sand for concrete, fine powder (0.074
mm or less) must be 7% or less, and it is actually traded under strict conditions of 5% or less.

[0005]

Therefore, conventionally, sand produced by a sand-making apparatus has been classified by a classification hopper, an air separator, or the like. However, sand having a particle size within a desired range and having a uniform particle size is obtained. It is difficult to get. Note that the first sieve through which sand having a particle size equal to or less than the maximum particle size in the desired particle size range passes, and the second sieve having sieves that prevent sand having a particle size of 0.074 mm or more from passing through are used. If sand that passes through one sieve and does not pass through the second sieve is obtained, it is possible to obtain sand within a target particle size range.

[0006] However, in such a method, the obtained sand has too large variation in particle size, so that not only there is a demand for uniform particle size as sand for concrete, but also the sand passed through the second sieve. Due to the particle size of 0.074 mm or less, there is a problem that the amount of fine powder that cannot be used out of specification and must be discarded is large, and the cost of sand rises. In addition, when the obtained sand is dropped and deposited on the sand yard from the tip of the belt conveyor, there is a problem that sand having a large particle size and sand having a small particle size are unevenly distributed. In particular,
Since this kind of sand making device is installed outdoors, there is also a problem that sand having a small particle size is blown off by wind.

[0007] Therefore, the present invention provides a milling method and a milling plant apparatus which can solve the above-mentioned problems, and in particular, obtains sand having a uniform particle size, and drops the obtained sand from the tip of a belt conveyor to a sand storage. A sand milling method and a sand milling plant apparatus suitable for a sand milling method and a sand milling plant apparatus in which sand having a large particle diameter and sand having a small particle diameter are not unevenly distributed even when they are deposited, and sand having a small particle diameter is not blown off by wind. The purpose is to provide.

[0008]

According to a first aspect of the present invention, there is provided a milling method comprising the steps of: a dry grinding step of pulverizing raw materials in a dry manner to obtain a powder; and a wet mixing step of mixing the obtained powder with water. And characterized in that:

[0009] According to the milling method of the first aspect,
By mixing the powder obtained in the dry pulverization process with water in a wet mixing device, the powder particles become in a constant and moderately water-absorbing state, and the amount of water added when used can be accurately controlled.

[0010] In particular, in the sand making method, the sand grains become constant and moderately water-absorbed, which makes it easy to accurately control the amount of water to be added when mixed with cement for use as concrete sand. In addition, due to moderate water absorption, not only does the sand grains themselves become slightly sticky, but also the water existing between the sand grains increases the adhesion between the sand grains, and around the sand grains having a relatively large grain size. Sand particles with a relatively small particle size adhere to each other and become lumpy, and since the lumps rub against each other in the mixing process, the corners are scraped off to form spheroids. Not only that, but also sand particles having a relatively large particle size and sand particles having a relatively small particle size are mixed with each other in a well-balanced manner, so that high-quality sand suitable for concrete and other uses can be produced.

Further, as described above, in the sand obtained by the present invention, sand particles having a relatively small particle size adhere around the sand particles having a relatively large particle size. When the particles are dropped and deposited on a sand yard, the sand particles having a relatively large particle size and the sand particles having a relatively small particle size are not unevenly distributed. In addition, when the obtained sand falls and accumulates on the sand storage place from the tip of the conveying means such as a belt conveyor outdoors, sand particles having a relatively small particle size are not blown off by the wind.

In the above description, the meaning of the term "sand particles having a relatively small particle size adheres around sand particles having a relatively large particle size" means that the particles are permanently fixed by, for example, an adhesive. Unlike the state in which the sand is used, it is a state in which it is temporarily attached for only several hours to several tens of hours from the time of sand making to the time when it is shipped and used as concrete sand by an appropriate amount of water. Therefore,
If it is left for a long time after sand making, the evaporation of water will cause the relatively small particle size sand particles to be separated from the relatively large particle size sand particles and not adhered, and Even if it is a short time after sand making, if it is mixed with cement and water, it will no longer be in a state of being separated and adhered by water entering between the sand grains.

According to a second aspect of the present invention, there is provided a milling method comprising the steps of: a dry pulverization step of pulverizing raw materials in a dry manner to obtain a powder; a classification step of classifying the obtained powder into a size within a predetermined range; And a wet mixing step of mixing the obtained powder with water.

[0014] According to the milling method of the second aspect,
Since the powder obtained by pulverizing the raw material in the dry process is classified and the powder within the appropriate particle size range is wet-mixed, the powder having a uniform particle size and the appropriate particle size is mixed. High quality powder can be easily manufactured.

[0015] In a third aspect of the present invention, in the wet mixing step, the water mixing ratio in the wet mixing step is set in a range of 2 to 5% by volume.

According to the method for milling according to the third aspect,
The powder contains a suitable amount of water, particularly in the sand making method, and the sand contains a suitable amount of water, so that the amount of water added when mixed with cement as concrete sand can be accurately controlled. In addition, it has a particle size with a suitable size,
It is possible to produce high-quality sand in which sand particles of various particle sizes are mixed at an appropriate mixing ratio.

According to a fourth aspect of the present invention, there is provided a milling plant apparatus comprising: a dry milling apparatus for milling raw materials in a dry manner to obtain powder; and a wet mixing apparatus for mixing the obtained powder with water. It is a feature.

According to the fourth aspect of the present invention, the powder obtained by mixing the powder pulverized by the dry pulverizer with water by the wet mixing apparatus becomes constant and moderately water-absorbing and is added when used. The amount of water can be precisely controlled.
In particular, in a sand-making plant apparatus, the amount of water added when mixing and using cement as sand for concrete can be accurately controlled by making the sand particles have a constant and appropriate water absorption state. In addition, the sand grains become moderately water-absorbing, which causes not only a slight stickiness of the sand grains themselves,
Due to the moisture existing between the sand grains, the adhesion between the sand grains increases, and the sand grains having a relatively small particle size adhere around the sand grains having a relatively large particle size to form a lump. Since the corners are scraped off and spheroidized by rubbing each other in the mixing process, not only sand having a spherical and uniform particle size as a whole is obtained, but also sand particles having a relatively large particle size and a relatively small particle size The sand grains are mixed well with each other, and high quality sand suitable for concrete and other uses can be obtained. Further, as described above, the sand obtained by the present apparatus has sand particles having a relatively small particle size adhered to the sand particles having a relatively large particle size. When the particles are dropped and deposited, sand particles having a relatively large particle size and sand particles having a relatively small particle size are not unevenly distributed. In particular, sand particles having a relatively small particle size are not blown off by wind.

According to a fifth aspect of the present invention, there is provided a milling plant apparatus comprising: a dry-type pulverizing apparatus for obtaining a powder by pulverizing raw materials in a dry type; and a classifying apparatus for classifying the obtained powder into a size within a predetermined range. And a wet mixing device for mixing the classified powder with water.

According to the milling plant apparatus of the fifth aspect, the powder within the standard particle size range classified by the classifying apparatus is mixed with water by the wet mixing apparatus, so that the powder has uniform and uniform particle size. Higher-grade powder mixed with powder having a particle size can be produced.

According to a sixth aspect of the present invention, there is provided a milling plant apparatus comprising: a raw material hopper; a dry pulverizing device for pulverizing the raw material supplied from the raw material hopper in a dry type to obtain a powder; A classification device for classifying the powder into a size within the range, a wet mixing device for mixing the classified powder with water, and a conveying means for returning the powder out of the specification range generated by the classification by the classification device to the raw material hopper. It is characterized by the following.

According to the flour mill plant of the sixth aspect, not only can high-quality flour be produced in the same manner as described above, but also flour out of the standard range generated by the classification by the classifier can be produced. Since the conveying means for returning to the raw material hopper is provided, the product out of the standard range can be supplied to the dry pulverizer again to be pulverized and used.

According to a seventh aspect of the present invention, there is provided a milling plant apparatus comprising: a raw material hopper; a coarse crushing device for coarsely crushing the raw material supplied from the raw material hopper; and a coarse powder crushed by the coarse crushing device. A first classifier, a dry pulverizer for pulverizing the powder classified by the first classifier in a dry manner to obtain a powder, a second classifier for classifying the obtained powder into a predetermined size, and a second classifier.
It has a wet mixing device for mixing the powder classified by the classifier with water, and a conveying means for returning the powder out of the specified range generated by the classification by the first classifier and the second classifier to the raw material hopper. It is characterized by the following.

According to the milling plant apparatus of the present invention, not only high-quality powder can be produced in the same manner as described above, but also the powder produced by the classification by the first and second classifiers. By providing a conveying means for returning the powders out of the specified range to the raw material hopper, the products out of the specified range can be supplied again to the coarse crushing device and the dry crushing device and used.

According to an eighth aspect of the present invention, in the flour milling plant, the wet mixing device has a drum-shaped main body having an inlet for powder and water on one side and an outlet on the other side, and an inner part of the main body. And a plurality of projections projecting therefrom, and are rotatably supported in an inclined manner with the input port facing upward.

According to the flour mill plant of the present invention, the mixing of the powder and water supplied from the charging port of the drum-shaped main body by the rotation of the main body and the stirring operation by the large number of projections are performed. Since the mixture flows and goes to the outlet while being mixed and agitated by the flow operation due to the inclination, from the lower outlet, in a constant and moderate water absorption state, almost spherical and uniform particle sizes, and powder particles of various particle sizes are attached. To produce a suitably mixed high-grade flour.

[0027]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a sand making method and a sand making plant according to an embodiment of the present invention. FIG. 1 is a schematic plan view of a sand making apparatus for carrying out the sand making method of the present invention, FIG. 2 is a front view, and FIG. 3 is a side sectional view taken along line AA in FIG.

In FIGS. 1 to 3, reference numeral 1 denotes a raw material hopper for feeding coarsely crushed raw materials, 2 denotes a belt feeder for conveying the raw material discharged from the outlet of the raw material hopper 1 in the horizontal direction, and 3 denotes a raw material from the belt feeder 2 Conveyor, which receives and transports the crushed sand, a crushing / classifying unit including a crushing / classifying unit having a sand maker for crushing the raw material conveyed by the belt conveyor 3 and a grading hopper for classifying the crushed sand; Is a belt conveyor for transporting sand pulverized and classified by the pulverizing / classifying device 4, and 6 is a belt conveyor 5.
A wet mixing device 7 mixes the sand conveyed with the water with water, and a belt conveyor 7 conveys the sand that has been subjected to the moisture absorption and mixing process by the wet mixing device 6. Reference numeral 8 denotes a fine powder receiving unit that receives fine powder (filler) out of the standard range generated by the pulverizing / classifying device 3, 9 denotes a belt conveyor that conveys the fine powder received by the fine powder receiving unit 8, and 10 denotes a belt conveyor that conveys the fine powder. It is a place for storing fine powder.

The raw material hopper 1 is for feeding raw materials from a dump truck that has transported crushed sand obtained by roughly crushing rough stones quarried on a mountain at the site. The raw material taking-out port of the raw material hopper 1 has its own weight inside the raw material hopper 1. It is in a low position so that raw materials can be taken out from

On the other hand, the pulverizing / classifying apparatus 4 is installed at a relatively high position in consideration of a sand processing step and a flow in a later step. For this reason, as is clear from FIG. 3, the belt conveyor 3 is installed obliquely so as to convey the raw material from a low position to a high position.

The pulverizing / classifying apparatus 4 is, for example, disclosed in
As described in Japanese Patent No. 64045, it is composed of a pulverizing / classifying unit having a sand making section for crushing raw materials to make sand and a classifying hopper for classifying the sand made. The sand making part is
The crushing chamber with the lower half around the rostral part and a rebound plate in the upper half of the crushing chamber, and a hammer that rotates at a high speed in the crushing chamber are mainly configured, and the raw material supplied into the crushing chamber is hit with a high-speed rotating hammer. Then, it is caused to collide with the repulsion plate, and is crushed by repeated impact and collision. On the other hand, the classifying hopper is installed below the roster, and includes a plurality of separation promoting plates that are inclined and disposed inside, and a shielding plate for adjusting the air volume and the particle size for appropriately adjusting the air classifying action of the fine powder in the sand particles. The sand particles dropped and discharged from the gap of the rostrum are separated into fine particles by air classification with the help of the separation accelerating plate in the middle of dropping, and the sand particles within a predetermined range are taken out from below. is there.

The raw material supplied to the pulverizing / classifying apparatus 4 is pulverized by a sand-making section of the pulverizing / classifying apparatus 4 and classified by a classification hopper. It is set appropriately according to the use by adjusting the plate.

In this way, the sand separated and removed from the fine powder and classified into the particle size specification range according to the purpose is supplied to the classification hopper 4.
b is discharged onto the belt conveyor 5 from the lower outlet and is conveyed to the wet mixing device 6.

As shown in FIGS. 4 (A) and 4 (B), the wet mixing device 6 has a charging port 6b at one end of a drum-shaped main body 6a.
And has an outlet 6c on the other side and a number of protrusions, for example, pins 6d, protruding toward the axis inside, and the outlet 6c is provided with a hopper 6e,
The lower portions of the four front and rear portions of the main body 6a are tiltably and rotatably supported by rollers 6f, 6f. Then, sand and an appropriate amount of water charged into the main body 6a from one input port 6b are mixed and agitated, and are discharged onto the belt conveyor 7 from the hopper 6e.

The protruding body protruding inside the main body 6a may be a blade, but may be a pin 6 shown in the illustrated example.
d is desirable not only because the resistance to the mixture of sand and water is low, but also because the mixture of sand and water is difficult to adhere. Further, it is desirable that the water supplied together with the sand from the inlet 6b be supplied in a spray state. In this way, by being supplied in a spray state, mixing with sand is performed in a short time and evenly.

The wet mixing device 6 is inclined so that the inlet 6b is at a high position and the outlet 6c is at a low position in consideration of the flow of sand in the main body 6a. It is installed at a relatively high position. For this reason, as apparent from FIG. 2, the belt conveyor 5 is installed obliquely so as to convey the sand discharged from the outlet of the classification hopper 4b at the low position to the wet mixing device 6 at the high position.

As shown in FIG. 2, the sand discharged from the hopper 6e of the wet mixing device 6 is conveyed by a belt conveyer 7 which is installed so as to be inclined forward and higher. It is dropped down and temporarily stored.

The fine powder (filler) out of the standard range classified by the sand making / classifying apparatus 4 is once received by the fine powder receiving section 8, conveyed by the belt conveyor 9, and stored in the fine powder storage 10.

According to the sand making plant configured as described above, the raw material charged into the raw material hopper 1 is conveyed to the crushing / classifying device 4 by the belt feeder 2 and the belt conveyor 3, and the crushing / classifying device 4 The sand pulverized by the sand making section is classified by a classification hopper, and only the sand within a desired particle size specification range is conveyed by the belt conveyor 5, and is charged into the main body 6a of the wet mixing device 6 by the inlet 6b.
And mixed and stirred with an appropriate amount of water also supplied from the charging port 6b. With this wet mixing,
Absorb the water into the sand grains and attach the sand grains together. The rate of water addition to sand differs depending on the application, and is set, for example, in a range of about 2 to 5% by volume ratio.

The wet mixing in which the sand is mixed and agitated with water in the wet mixing device 6 causes the sand grains to be in a uniform water-absorbing state, thereby reducing the amount of water used for mixing with cement as concrete sand. Be able to control accurately. Further, when the sand is in a water-absorbing state, the sand grains themselves become slightly sticky, and due to the water existing between the sand grains, the adhesive force between the sand grains is increased. As shown in (B), sand particles S2 and S2 'having a relatively small particle size adhere to the periphery of sand particles S1 and S1' having a relatively large particle size to form a lump and a large particle size.
Further, as they rub against each other in the drum-shaped main body 6a, the corners are cut off, and the sand particles S, which have a shape close to a sphere as a whole and have relatively uniform particle sizes D1, D2, are obtained.
S ′ is obtained, and sand particles S having a relatively large particle size are obtained.
1, S1 'and sand particles S2, S2' having a relatively small particle size are in a well-mixed state as sand for concrete. Therefore, high quality sand can be manufactured. In addition, when such sand is conveyed by the subsequent belt conveyor 7 and dropped and deposited on the sand yard from the leading end thereof, sand particles having a large particle diameter and sand particles having a small particle diameter like conventional dry sand are obtained. Is not unevenly distributed, and in particular, there is a feature that sand particles having a small particle diameter are not blown off by wind even outdoors.

Table 1 and FIG. 6 show an example of the sand obtained by the method and the sand making plant of the present invention.

[0042]

[Table 1]

As shown in Table 1 and FIG. 6, according to the above sand making plant apparatus, when the sieve is 5.0 mm, the crushed product residual ratio is 8.9%, and the 2.5 cut residual ratio is 0.0%. , Sieve mesh 0.
At 074 mm, the residual ratio of crushed products is 99.5%, the residual ratio of 2.5 cuts is 99.3%, and the residual ratio of crushed products is close to the JIS standard range.
It is the median of the IS standard range, and it can be seen that it has high quality.

FIG. 7 is a plan view of a sand making plant apparatus according to another embodiment for carrying out the sand making method of the present invention, and FIG.
9 is a front view, and FIG. 9 is a side sectional view taken along line AA in FIG.

In the sand making plant of this embodiment, the raw material hopper 1 is installed at a high position close to the pulverizing / classifying device 4, and the raw material is directly fed from the raw material storage site at a low position by the belt conveyor 11 accordingly. It is designed to be transported to a crushing / classifying device 4 installed at a high position. Other points are the same as those of the embodiment of FIG. 1, and therefore, the same reference numerals as those of FIG.

According to this embodiment, the belt conveyor 1
Even if there is no raw material on the raw material supply side, if there is raw material in the raw material hopper 1, the sand making operation can be continued, so that the belt conveyor 11 can be stopped in such a state.

FIG. 10 is a plan view of a sand making plant for carrying out a sand making method according to still another embodiment of the present invention, FIG. 11 is a front view, and FIG. 12 is a sectional view taken along line AA in FIG. It is a side sectional view along.

This embodiment is shown in FIGS. 1 to 3 and FIGS.
A horizontal vibrating sieve 12 is installed between the pulverizing / classifying device 4 and the wet mixing device 6 in FIG. 10, and the belt conveyor 5 in FIGS. 1 to 3 and FIGS. A belt conveyor 5a for conveying sand from the crushing / classifying device 4 to the horizontal vibrating sieve 12 and a belt conveyor 5b for conveying sand from the horizontal vibrating sieve 12 to the wet mixing device 6 are provided. Also, coarse sand out of the specified range generated by classification by the horizontal vibrating sieve 12 is transferred to the belt conveyor 13.
To return to the raw material hopper 1. Other configurations are the same as those of the sand making plant apparatus shown in FIGS. 1 to 3 and FIGS.

According to the sand making device of this embodiment,
Between the classifying device 4 and the wet mixing device 6, a horizontal vibrating sieve 12
Is provided, so that the grain size of the sand conveyed to the wet mixing device 6 can be controlled more precisely, and there is a feature that the production of sand more suitable for the intended use becomes possible. In addition, coarse sand out of the standard range generated as a result of the classification in the horizontal vibrating sieve 12 is returned to the raw material hopper 1 by the belt conveyor 13, and the coarse sand out of the standard range is again supplied to the crushing / classifying device 4. There is also a feature that it can be used.

FIG. 13 is a plan view of a sand making plant according to still another embodiment of the present invention, and FIG.
13 is a front sectional view taken along the line AA in FIG. 15, and FIG. 15 is a partial front view taken along the line BB in FIG.

In FIGS. 13 to 15, reference numeral 20 denotes a raw material hopper for charging raw stones, 21 denotes a single toggle crusher for coarsely crushing raw stones, and 22 denotes a first horizontal for classifying crushed sand coarsely crushed by the single toggle crusher 21. A vibrating sieve, 23 is an intermediate hopper, 24 is a belt feeder for horizontally transporting the raw material from the raw material hopper 20, 25 is a belt conveyor for receiving the raw material from the belt feeder 24 and transporting the raw material to the single toggle crusher 21, and 26 is a single conveyor. A belt conveyor for conveying the crushed sand crushed by the toggle crushing device 21 to the first horizontal vibrating sieve 22, a belt conveyor 27 for conveying the sand classified by the first horizontal vibrating sieve 22 to the intermediate hopper 23, and a belt conveyor 27. A bucket conveyor for feeding the sand conveyed by the intermediate hopper 23 into the intermediate hopper 23 from the input port of the intermediate hopper 23, The coarse sand outside the standard range produced is classified with a sieve 22 is a belt conveyor to return the raw material hopper 20. Other configurations are the same as those in FIGS. 1 to 3, 7 to 9, and 10 to 12.

According to the sand making plant of this embodiment, the raw ore collected from the mountain is put into the raw material hopper 20,
The belt is conveyed to the single toggle crusher 21 by the belt conveyor 25, and coarse sand can be formed. The coarse sand which has been classified by the first horizontal vibrating sieve 22 and out of the standard range is transferred to the belt conveyor 29.
Thus, the returned coarse sand can be again supplied to the single toggle crushing device 21 and used for sand making. Further, as mentioned above,
Since the coarse sand classified by the second horizontal vibrating sieve 12 and out of the standard range is returned to the raw material hopper 20 by the belt conveyor 13, the coarse sand is again supplied to the single toggle crushing apparatus 21 to produce sand. Can be used.

In the above embodiment, the sand making method and the sand making plant apparatus have been described. However, the present invention can also be used as a milling method and a milling plant apparatus for other raw materials. For example, the present invention can be applied to milling by crushing raw materials such as calcium carbonate, wood and other waste materials.

[0054]

The milling method of the present invention is characterized by comprising a dry pulverizing step of pulverizing raw materials in a dry manner to obtain a powder, and a wet mixing step of mixing the obtained powder with water. Thus, by mixing the powder obtained in the dry grinding step with water in the wet mixing step, the powder particles become in a proper water absorbing state, and the amount of water added when the powder is used can be accurately controlled. In particular, in the sand making method for concrete, the sand particles are in a constant and moderately water-absorbing state, so that the amount of water added at the time of mixing and using sand and cement can be accurately controlled. In addition, not only does the sand grain itself have some stickiness, but also the moisture existing between the sand grains increases the adhesion between the sand grains, and relatively small grains surround the relatively large grain. Sand particles with a diameter adhere to each other and become clumps, and since the clumps rub against each other in the mixing process, the corners are shaved off and spherical, so that not only spherical sand particles having a uniform particle size as a whole can be obtained, Since sand particles having a relatively large particle size and sand particles having a relatively small particle size are mixed in a well-balanced manner, high-grade sand suitable for concrete and other uses can be produced. Further, as described above, the sand obtained by the present invention has sand particles having a relatively small particle size adhered around the sand particles having a relatively large particle size. When the particles are dropped and deposited on the sand, the sand particles having a relatively large particle size and the sand particles having a relatively small particle size are not unevenly distributed, and in particular, the effect that the sand particles having a relatively small particle size are not blown off by the wind. Can play.

Further, the milling plant apparatus of the present invention is characterized by comprising a dry pulverizing apparatus for obtaining a powder by pulverizing raw materials in a dry manner, and a wet mixing apparatus for mixing the obtained powder with water. Therefore, by mixing the powder pulverized by the dry pulverizer with water by the wet mixer, the powder particles are brought into a constant and appropriate water absorption state in the wet mixer, and the amount of water added at the time of use can be accurately controlled. In particular, in the sand making plant apparatus, the sand particles are in a constant and appropriate water absorbing state, and the amount of water added at the time of mixing and using sand and cement can be accurately controlled. In addition, not only does the sand itself produce some stickiness,
Due to the water existing between the sand grains, the adhesion between the sand grains increases, and the sand grains having a relatively small particle diameter adhere to the sand grains having a relatively large particle diameter to form a lump. Since the corners are scraped off and spheroidized by rubbing each other in the mixing process, not only spherical sand particles having a uniform particle size as a whole are obtained, but also sand particles having a relatively large particle size and a relatively small particle size Since the grains are mixed with the sand grains in a well-balanced manner, high-grade sand suitable for concrete and other uses can be obtained. Further, as described above, the sand obtained by the present invention has sand particles having a relatively small particle size adhered around the sand particles having a relatively large particle size. When falling and depositing on, sand particles having a relatively large particle size and sand particles having a relatively small particle size are not unevenly distributed,
In particular, sand particles having a relatively small particle size are not blown off by the wind outdoors.

[Brief description of the drawings]

FIG. 1 is a plan view of a sand mill plant apparatus according to a first embodiment for performing a milling method of the present invention.

FIG. 2 is a front view of a sand mill plant apparatus according to a first embodiment for performing the milling method of the present invention.

FIG. 3 is a front sectional view along AA of FIG. 1 in the sand mill plant apparatus of the first embodiment for performing the milling method of the present invention.

FIG. 4A is a front view of a wet mixing apparatus according to an embodiment of the present invention, and FIG. 4B is a side view.

FIG. 5A is a schematic enlarged sectional view of sand obtained by the embodiment of the present invention, and FIG. 5B is a schematic enlarged sectional view of another sand.

FIG. 6 is a particle size distribution diagram of the sand obtained by the present invention.

FIG. 7 is a plan view of a sand mill plant apparatus according to a second embodiment for performing the milling method of the present invention.

FIG. 8 is a front view of a sand mill plant apparatus according to a second embodiment for implementing the milling method of the present invention.

FIG. 9 is a side sectional view taken along the line AA of FIG. 7 in the sand mill plant apparatus of the second embodiment for performing the milling method of the present invention.

FIG. 10 is a plan view of a sand mill plant apparatus according to a third embodiment for performing the milling method of the present invention.

FIG. 11 is a front view of a sand mill plant apparatus according to a third embodiment for performing the milling method of the present invention.

FIG. 12 is a side sectional view taken along line AA of FIG. 10 in a sand mill plant apparatus according to a third embodiment for performing the milling method of the present invention.

FIG. 13 is a plan view of a sand mill plant apparatus according to a fourth embodiment for performing the milling method of the present invention.

FIG. 14 is a front sectional view taken along line AA of FIG. 13 in a sand mill plant apparatus according to a fourth embodiment for implementing the milling method of the present invention.

FIG. 15 is a partial front view taken along the line BB of FIG. 13 in a sand mill plant apparatus according to a fourth embodiment for performing the milling method of the present invention.

[Explanation of symbols]

1,20 Raw material hopper 3,5,5a, 5b, 7,9,11,25,26,27
Conveying means (belt conveyor) 4 Pulverizing / classifying device 6 Wet mixing device 6a Main body 6b Input port 6c Outlet 6d Projection (pin) 6f Roller 12 Classifier (horizontal vibration sieve, second classifier, second horizontal vibrating sieve) 13 , 29 Conveying means (belt conveyor for return) 21 Coarse crusher (single toggle crusher) 22 First classifier (first horizontal vibrating screen) 23 Intermediate hopper

Claims (8)

[Claims] 1. A milling method comprising a dry pulverization step of pulverizing raw materials in a dry manner to obtain a powder, and a wet mixing step of mixing the obtained powder with water. 2. A dry pulverization step of pulverizing raw materials in a dry manner to obtain a powder, a classification step of classifying the obtained powder into a size within a predetermined range, and a wet mixing step of mixing the classified powder with water. And a milling method comprising: 3. The milling method according to claim 1, wherein in the wet mixing step, the water addition rate to the powder is set in a range of 2 to 5% by volume ratio. 4. A milling plant apparatus comprising: a dry pulverizing apparatus for pulverizing raw materials in a dry system to obtain a powder; and a wet mixing apparatus for mixing the obtained powder with water. 5. A dry pulverizing apparatus for pulverizing raw materials in a dry manner to obtain powder, a classifying apparatus for classifying the obtained powder into a size within a predetermined range, and a wet mixing apparatus for mixing the classified powder with water. And a milling plant apparatus comprising: 6. A raw material hopper, a dry grinding device for pulverizing a raw material supplied from the raw material hopper in a dry manner to obtain powder, a classification device for classifying the obtained powder into a size within a predetermined range,
A flour milling plant apparatus comprising: a wet mixing device that mixes the classified powder with water; and a conveying unit that returns a powder out of a specification range generated by the classification device to a raw material hopper. 7. A raw material hopper, a coarse crushing device for coarsely crushing the raw material supplied from the raw material hopper, a first classifying device for classifying the coarsely crushed coarse powder by the coarse crushing device, and a classification by the first classifying device. Dry crushing apparatus for crushing the obtained coarse powder in a dry manner to obtain powder, a second classifier for classifying the obtained powder to a predetermined size, and wet mixing for mixing the powder classified by the second classifier with water. A flour milling plant apparatus comprising: an apparatus; and conveying means for returning powder out of a specified range generated by the first classifier and the second classifier to a raw material hopper. 8. The wet mixing apparatus comprises a drum-shaped main body having sand and water inlets on one side and outlets on the other side, and a number of projections protruding inside the main body. The flour mill plant apparatus according to any one of claims 4 to 7, wherein the milling plant apparatus is supported in an inclined manner freely and with the input port facing upward.