JP2003010726A - Method and apparatus for manufacturing crushed sand - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and an apparatus for manufacturing crushed sand for concrete or the like by which the crushed sand corresponding to a dam aggregate standard can be manufactured by keeping the apparatus under control according to the particle size of the manufactured crushed sand while grasping the particle size distribution precisely. SOLUTION: The crushed sand having the prescribed coarse particle rate (FM value) is manufacture in a sand manufacturing factory by controlling a raw material storing means 1, a raw material supplying means 2 or a crushing means 3 for crushing the mined ore so that the particle size distribution or particle weight distribution of the crushed sand stands within the predetermined allowable range. The particle size and the particle size distribution or particle weight distribution are obtained by imaging the whole or part of the crushed sand discharged from the means 3 by an optical means 5 to obtain image information and measuring the projected area of each of the sand particles on the basis of the image information by using an image analyzing means incorporated in a central processing unit 6 and performing calculations by using the measured projected area.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is a concrete which is introduced with a technique for sensing and controlling not only particle size but also particle size distribution when crushing raw ore to produce crushed sand having a predetermined coarse particle ratio (FM value). TECHNICAL FIELD The present invention relates to a method and an apparatus for producing crushed sand used for industrial use, asphalt, water pipes and the like. Here, the crushed sand includes not only fine-grained sand but also crushed rock of a certain size.

[0002]

2. Description of the Related Art When crushing raw mined stones to produce crushed sand, it is known that the crushed sand is sieved so as to have a predetermined coarse grain ratio and then crushed by a sand maker. For example, JP-A-8
This is as disclosed in Japanese Patent Publication No. 173835.

In such a conventional example, the product discharged from the sand maker is made into a certain mesh (for example, 2.5 m).
This is a method of estimating the FM value at a ratio of +2.5 and -2.5 mm by selecting in m). Therefore, the particle size distribution of details cannot be controlled.

In general, when the FM value is changed and controlled, for example, in a rod mill, the raw material supply amount, the supply water amount and the rod amount are controlled, but it is impossible to adjust the rod amount during operation. At present, there are few skilled workers called craftsmen who can control the amount of water supplied.
Therefore, the current situation is to control only the raw material supply amount.

[0005]

Among the above-mentioned conventional examples, FM
In the example of estimating the value, when analyzing the obtained crushed sand,
Even if the coarse particle ratio (FM value) representing the particle size (roughness) of sand is the same, the particle size distribution is often different. That is, the standard value is FM2.7.
Even if a JIS standard FM2.68 product is created with a value of ± 0.1, the content of the particle can be analyzed to analyze the particle size distribution. There exists FM 2.68 which does not fall within the range of).

Looking at the particle size distribution of the particle size of 0.60 in FIG. 7, it should be understood that the upper limit value of 30% by the Japan Society of Civil Engineers should be exceeded, but it is out of this range.

With the current sand making method, the standard value is FM2.7 ±
The following method is adopted in order to set the value to 0.1 within the range of the above-mentioned dam aggregate standard.

(A) A method in which the maximum grain size of FM2.6 is used and the fine grain portion is increased to the standard value to reduce the ratio of the grain size exceeding the standard value, or

(B) A method in which a plurality of production lines are used to produce products having different particle sizes and they are mixed so that they fall within the standard range.

In the former case (a), not only the production amount per hour is suppressed and the operation time is extended, but also a large amount of ultrafine grain portions (which cannot be used as aggregates) are produced as a by-product, and This leads to an increase (expansion of natural alteration range) and an increase in waste cake (industrial waste) after turbid water treatment. In the latter (b), the number of equipment machines increases, equipment costs increase, and plant (machine arrangement) However, there is a problem that the cost becomes large due to complicated maintenance and management.

When the FM value is changed and controlled, the roller mill can be controlled by the raw material supply amount and the pressing pressure of the roller, and the impact crushing type mill can be controlled by the raw material supply amount and the rotation speed of the rotor. . Even in the case of a compression type crusher such as a rod mill, the amount of raw material supplied and the amount of supplied water are changed, but there is a problem that even if a small amount is changed, the FM value is greatly changed and control is difficult.

The object of the present invention is to solve the above-mentioned drawbacks of the conventional example and to achieve a very accurate value (for example, FM) with respect to the standard value.
2.7) production is possible, and the equipment cost and maintenance cost can be reduced with the production equipment of one series line, especially the particle size distribution state of the sample carried out from the compression type crusher such as a rod mill is confirmed. By controlling the distribution state with a specified standard value, it is possible to efficiently and easily produce high-quality crushed sand in large quantities, contributing to cost reduction and protection of the natural environment, expanding production capacity and stabilizing quality. It is intended to provide a method and an apparatus for producing crushed sand that can be used for concrete and other asphalt.

[0013]

Means for Solving the Problems As a result of intensive studies, the present inventors have found that the above object can be achieved by using an image analysis means as means for confirming the particle size distribution state, and complete the present invention. Came to.

In the method for producing crushed sand according to the first aspect of the present invention, a raw ore is crushed in a sand factory to obtain a predetermined coarse grain ratio (FM).
In the method for producing crushed sand for concrete or the like having the value), the raw ore is crushed by the crushing means through the raw material storing means and the raw material supplying means, and the whole or a part of the crushed sand carried out from the crushing means is used by the optical system means. The image information is picked up and image information is obtained, and the image analysis means incorporated in the central processing unit is used to measure the projected area of each sand grain to calculate the particle size and particle size distribution or weight distribution. Alternatively, the method for producing crushed sand is such that the raw material storage means, the raw material supply means, or the crushing means is controlled so that the weight distribution falls within a predetermined allowable range.

According to the second aspect of the present invention, each projected area of the sand grains is measured by binarization processing such as black and white or shading.

In the third aspect of the invention, the projected area of each sand grain is measured as the area of a closed curved line of various sizes represented by reproducing each contour of the sand grain on the image.

In the fourth invention, the particle size distribution or the weight distribution is calculated by converting each size of the sand grains into the circle equivalent diameter of the projected area.

In the fifth invention, the particle size distribution or the weight distribution is calculated by converting each shape of the sand grains into a geometrically simple cube such as a sphere or a rectangular parallelepiped.

In the sixth invention, the particle size distribution or the weight distribution is
It was decided to display it as a graph such as a curve or histogram.

According to a seventh aspect of the invention, in a manufacturing apparatus for crushing raw mined stones in a sand factory to produce crushed sand having a predetermined coarse grain ratio (FM value), raw material storing means for raw mined stones, raw material supplying means, Crushing means, means for discharging the crushed crushed sand, optical system means for imaging the crushed sand, means for measuring the projected area of each sand grain from the obtained image information, and particle size and particle size distribution or weight distribution of the crushed sand And means for comparing the particle size distribution or weight distribution with a predetermined allowable range, and means for controlling the raw material storage means or raw material supply means or crushing means based on the comparison result. It was used as a crushed sand manufacturing device.

In the eighth invention, means for displaying the particle size distribution or the weight distribution in the form of a curve, a histogram or the like is provided.

(Operation) In the first aspect of the invention, the raw ore stone is crushed by the crushing means through the raw material storage means and the raw material supply means, and the crushed sand carried out from the crushing means is kept stationary or moving on a conveyor, for example. Since the sand grains are imaged by the optical system means and used as image information, the projected area of each sand grain can be measured by the image analysis means built in the central processing unit, and the grain size and the grain size distribution can be calculated.

If specific gravity is added to the measurement result, it can be immediately converted into a weight distribution and a particle size distribution curve can be drawn by plotting particle size-cumulative weight percentage, and the entire particle size distribution can be grasped. Moreover, since a histogram and a pie chart in which the particle size and the weight percentage by particle size are plotted can be drawn, it is possible to grasp the weight ratio of each particle size category.

According to the present invention, not only the conventional particle size but also the particle size distribution can be sensed, so that the entire particle size distribution can be grasped and the insufficient particle size classification and the excessive particle size distribution can be found. Since it can be confirmed by the display means, it is possible to control the feed amount of the raw material and the feed water amount, or change the crushing means itself to feed back to the crushed sand production.

In the second aspect of the invention, when image measurement is performed by various general-purpose image analysis means, binarization processing and color extraction are performed in order to separate the required image and background from the shade and color of the image. Be seen. Since it is difficult to recognize particles by color extraction in the measurement of sand grains in the present invention, it was decided to perform binarization processing using black and white or shading.

According to the third aspect of the invention, in a normal binarization method, there is a fear that a light-exposed portion and a shaded portion may be recognized as different particles, and black and white or shaded portions are connected to each other. Since many matched particles may be recognized as one area, in the binarization process for analyzing irregular particles such as crushed rocks and sand grains, image adjustment such as illuminance and contrast, noise removal and After processing appropriate pre-processing for irregular particle analysis such as filter processing such as line, valley line, and edge detection, each contour is reproduced so that particles can be recognized with various large and small closed curves. did.

In the fourth aspect of the invention, the particle size distribution or the weight distribution is calculated by converting each size of the sand grains into a circle-equivalent diameter of the projected area, so that the calculation can be simplified.

In the fifth invention, regarding the particle size in the particle size measurement of the sand particles of the present invention, since irregularly shaped particles such as crushed rocks and sand particles have a very complicated shape, the shape can be a geometrical shape such as a sphere or a rectangular parallelepiped. I converted it to a simple cube and expressed the dimensions. For example, when measuring from a projected view on a plane by image information or the like, a method in which the length of the long axis, the average length of the long and short axes, or the maximum length in a certain direction is used as a representative dimension, or a circle corresponding to the projected area A projected area circle equivalent diameter that expresses a particle diameter by a diameter or the like is used.

Among these, in the particle size measurement of the sand grains in the present invention, the projected area circle equivalent diameter is used in order to calculate and use the particle size distribution or the weight distribution from the measurement results. Furthermore, in order to measure the particle size distribution of irregular and fine particles such as sand particles, or to grasp the depth direction and the entire particle size distribution from a part of image information on a plane, it is necessary to use 3D from the two-dimensional particle size information.
It is also possible to use stereoanalysis or the like using geometric probability theory in order to convert into a dimensional particle size distribution.

In the sixth invention, the particle size distribution or the weight distribution is
Displayed in graphs such as curves and histograms so that they can be clearly grasped visually.

According to a seventh aspect of the invention, in a crushed stone manufacturing apparatus that crushes a mined raw stone in a sand factory to have a predetermined coarse grain ratio (FM value), a raw material storage means for the raw mined stone, a raw material supply means,
Crushing means, means for discharging the crushed crushed sand, optical system means for imaging the crushed sand, means for measuring the projected area of each sand grain from the obtained image information, and particle size and particle size distribution or weight distribution of the crushed sand And means for comparing the particle size distribution or weight distribution with a predetermined allowable range, and means for controlling the raw material storage means or raw material supply means or crushing means based on the comparison result. It was

In particular, image processing is performed by an optical system means for imaging the crushed sand, a means for measuring the projected area of each sand particle from the obtained image information, and a means for calculating the particle size and particle size distribution or weight distribution of the crushed sand. Therefore, it has become possible to obtain a very accurate particle size and particle size distribution or weight distribution situation. Then, based on this information, the raw material storage means, raw material supply means, or crushing means for the raw mined stone is controlled to ensure that crushed sand centered on the standard value is obtained.

In the eighth aspect of the invention, means for displaying a graph such as a curve or a histogram is used as the manufacturing apparatus to enable visual confirmation.

[0034]

BEST MODE FOR CARRYING OUT THE INVENTION In the present invention, a particle size distribution, which was not clear in the conventional JIS standard by sieving, is analyzed by using an image analysis means, and the projected area of each sand grain is measured. Also, the particle size distribution centered on the weight and the predetermined particle size per unit area is calculated and controlled.

[0035]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A method and an apparatus for producing crushed sand for concrete according to the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic view showing an example of a manufacturing process for automatically manufacturing crushed sand. In FIG. 1, 1 is a raw material storage means for crushed sand, 2 is a raw material supply means, and 3 is a crushing means. For example, a crushed sand supplied from the raw material supply means 2 is finely crushed by using a rod mill and carried out from an outlet portion. Has become. Reference numeral 4 denotes a conveyor for transportation, and 5 denotes an optical system means. In the optical system means 5, the crushed sand on the conveyor 4 is in a moving state or in a static state, and the state of the raw material in a certain range is imaged to be image information, and an image analysis means is built in and accumulated as data, processing, and control signals. To a central processing unit (CPU) 6 capable of inputting and outputting. 7 is a water supply means, which is provided in the crushing means 3.

In the raw material supply means 2, it is also possible to previously remove particles having a particle size larger than a predetermined one by using a filter or the like. Further, although a rod mill is shown as an example of the crushing means 3 and the rod 8 inside is shown, the raw material can be crushed by using a roller mill, an impact crushing type mill or other crushing means, and the present invention is not limited to this. Not done.

During the transportation by the conveyor 4 for transportation, which is discharged from the outlet of the crushing means 3, for example, the state of sand grains is imaged from above by the optical system means 5 and sent to the image analysis means. The crushed sand imaged may remain in the transportation state or may be in the stationary state.

Examples of the optical system means 5 include laser and C
It suffices if the sand grains can be imaged by a CD camera, a digital camera, a video camera or the like.

FIG. 2 shows image information in which the raw material is imaged in black and white and light and shade, and the contours of each sand grain are divided by various closed curves of different sizes. The projected area of these crushed sands can be easily measured as the area of the closed curve.

FIG. 3 is an enlarged image of an example of the material crushed by the crushing means, and the circumference of each crushed sand is indicated by a closed curve. It turns out that each crushed sand has rounded corners.

In the particle size measurement of the sand grains of the present invention, it is particularly desirable to bring the optical system means 5 close to or to enlarge the image in order to image the fine particles. It is desirable to be in a state of moving in.

The central processing unit 6 outputs a control signal when the optical system means 5 captures an image, and makes the conveyor 4 in a stationary state, or
Alternatively, it can be slowed down. In addition, the raw material supply means is controlled, the conveying conveyor 4 is branched so that the conveying speed is reduced only for imaging, or an imaging pedestal is installed, and a sand grain to be imaged is conveyed to this pedestal. A method of sampling by scooping from 4 is also possible.

The image analysis means can measure the projected area of each sand particle based on the obtained image, and calculate the particle size and weight of the crushed sand, and the particle size distribution centered on the predetermined particle size. In order to improve the accuracy of particle size measurement, the image analysis means improves the accuracy by correcting the analysis result based on the result of actual sieving in advance and by adding up the results of several images in one measurement. The means to do is built in.

Based on the result of this analysis, the amount of raw material supplied from the central processing unit 6 to the crushing means 3 and the crushing means can be controlled or can be automatically controlled by issuing a control signal to control the amount of supplied water. The state of each stage of the above process can be visually observed by a graph or a calculated numerical value on a display device, for example, which facilitates control operation.

As shown in FIG. 2 and FIG. 3, the sand grains 9 conveyed on the conveyor are different in size, and are closed closed fine wires 1.
Each contour is represented by 0. From this contour, the grain size of each sand grain is measured by image analysis means.

For example, considering a rectangle having the same area as the area surrounded by the partition thin line 10, assuming a sphere having the same circle diameter as this area, and multiplying the specific gravity as crushed sand, the weight can be calculated, and graphing is easy. Is. Examples of software include WipFrag manufactured by WipWare and software manufactured by SPLIT ENGINEERING.

FIG. 4 is a histogram (histogram) calculated by multiplying the specific gravity of the rough stone from the projected area of the sand grains according to the contours of FIGS. 2 and 3 and plotting the particle size on the horizontal axis and the weight by particle size on the vertical axis. ), Showing the distribution of sand grains centered on 0.6 mm, with a large amount of crushed sand on the smaller grain size side.

FIG. 5 is a particle size distribution curve diagram in which the calculation results are similarly plotted with the particle size on the horizontal axis and the cumulative weight percentage on the vertical axis.

FIGS. 6 and 7 show the particle size distribution value and the particle size distribution curve of the fine aggregate measured by the dam aggregate standard (standard of the Japan Society of Civil Engineers) by the method for producing crushed sand of the present invention.

As shown in FIG. 7, the dam aggregate standard requires that the particle size distribution according to each particle size not be located between the upper limit value and the lower limit value of the dotted line. It is found that the 6 mm portion exceeds 30% of the upper limit value. Therefore, based on the result determined by the image analysis means, a signal is issued to the crushing means to control the crushed sand in a portion exceeding the upper limit value to be divided into small pieces. The crushing means 3 can also control the amount of raw material supplied, the amount of water supplied, or the crushing means, which facilitates the management of sand production.

Generally, with a crushing means such as a rod mill, it is impossible to change the rod amount during operation.
Raw material storage means 1 or raw material supply means 2 for crushed sand in FIG.
Or the water supply amount is controlled by the water supply means 7. When the particle size distribution is largely different, the raw material supply amount can be adjusted, and the small difference can be selected by adjusting the water supply amount or the like, but in the present invention, the actual sand grains are imaged and calculated without relying on intuition by a skilled worker. It became possible to adjust the particle size distribution by adjusting the numerical values.

Since the past data of various crushed sands in the sand factory are accumulated in the central processing unit 6 having the built-in image analysis means in advance, the change of the raw material supply amount and the supplied water amount can be easily calculated by this data. , Sand management has become extremely quick and accurate. Therefore,
For example, an automatic operation system has made it possible to produce in the middle of standard values, and it has also become possible to reduce equipment costs and maintenance costs with one-line production equipment. It is also possible to manually control a part of the sand making means.

FIGS. 8 and 9 show the measured values and distribution charts according to the JIS standard, and the analysis is based on the exact same data as in FIGS. 6 and 7, but the upper limit of the particle size distribution is as shown in FIG. It was not possible to analyze that the particles jumped at the grain size of 0.60, and it was found that the JIS standard did not pass the dam aggregate standard.

[0055]

Industrial Applicability According to the present invention, it is possible to produce in an automatic operating system or partially manually, for example, in the middle of the standard value, and the predetermined particle size and the particle size distribution centered on the particle size are within the allowable range. In order to fit it, the crushing means was controlled so that the amount of crushed sand on the small grain side increased, and it became possible to accurately control the production of crushed sand as fine aggregate that falls within the strict standards for dam aggregates. The quality is improved and the particle size distribution is managed efficiently. In addition, since production can be performed with a single-line production facility, facility costs and maintenance costs can be reduced, and high-quality crushed sand can be efficiently produced in large quantities and easily.

Since the production is performed while controlling the particle size distribution, unnecessary ultrafine grain portions (which cannot be used as aggregates) are not produced in large amounts as by-products, which contributes to cost reduction and increases in the amount of raw ore ( There is no concern about the expansion of the range of natural alteration) and the increase of waste cake (industrial waste) after turbid water treatment, which contributes to the protection of the natural environment, and the production of crushed sand for concrete, etc., which can expand production capacity and stabilize quality A method and manufacturing apparatus can be provided.

[Brief description of drawings]

FIG. 1 is a schematic view showing an example of a crushed sand manufacturing process by the method of the present invention.

FIG. 2 is a reference diagram showing image information by an optical system means.

FIG. 3 is a reference diagram showing enlarged image information by an optical system means.

[Fig. 4] Example of particle size distribution analysis diagram based on image information

FIG. 5: Example of particle size distribution graph based on image information

[Fig. 6] Example of data values based on dam aggregate standards

FIG. 7: Example of particle size distribution map of the same as above

FIG. 8: Example of data value based on JIS standard

FIG. 9: Particle size distribution diagram of the same as above

[Explanation of symbols]

1: Raw material storage means 2: Raw material supply means 3: Crushing means 4: Conveyor for transportation 5: Optical system means 6: Central processing unit (CPU) 7: Water supply means 9: Crushed sand 10: An example of a closed curve that represents the contour of a sand grain

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Akitsugu Nakayama             4-16 Josaigaoka, Munakata City, Fukuoka Prefecture (72) Inventor Masaaki Nishi             6-4100 Asahi-cho, Nobeoka-shi, Miyazaki Asahi Kasei             Within the corporation F-term (reference) 4D067 EE45 FF02 FF14 FF15 GA03                       GB01

Claims (8)

[Claims] 1. A method for producing crushed sand for concrete or the like having a predetermined coarse grain ratio (FM value) by crushing raw ore in a sand factory, and crushing raw ore through raw material storage means and raw material supply means. The whole or a part of the crushed sand discharged from the crushing means is imaged by the optical system means as the image information, and the image analysis means built in the central processing unit is used for this image information, Calculate the particle size and particle size distribution or weight distribution by measuring each projected area, and control the raw material storage means, raw material supply means or crushing means so that this particle size distribution or weight distribution falls within a predetermined allowable range. A method for producing crushed sand, characterized in that 2. The method for producing crushed sand according to claim 1, wherein the measurement of the projected area of each of the sand grains is performed by a binarization process such as black and white or shading. 3. The measurement of the projected area of each sand grain is performed as an area of a closed curved line of various sizes represented by reproducing each contour of the sand grain on the image. The method for producing crushed sand according to. 4. The production of crushed sand according to claim 1, wherein the particle size distribution or the weight distribution is calculated by converting each size of the sand grains into a circle equivalent diameter of the projected area. Method. 5. The particle size distribution or the weight distribution is calculated by converting each shape of the sand grains into a geometrically simple cube such as a sphere or a rectangular parallelepiped. The method for producing crushed sand according to. 6. The method for producing crushed sand according to claim 1, wherein the particle size distribution or the weight distribution is displayed by a graph such as a curve or a histogram. 7. A manufacturing apparatus for crushing raw ore in a sand factory to produce crushed sand having a predetermined coarse grain ratio (FM value), a raw material storage means, a raw material supplying means, and a crushing means for the raw ore. , Means for carrying out the crushed sand, optical means for imaging the crushed sand, means for measuring the projected area of each sand grain from the obtained image information, and calculating the grain size and particle size distribution or weight distribution of the crushed sand Means, means for comparing the particle size distribution or weight distribution with a predetermined allowable range, and means for controlling the raw material storage means, raw material supply means or crushing means based on the comparison result. An apparatus for producing crushed sand. 8. The crushed sand manufacturing apparatus according to claim 7, further comprising means for displaying the particle size distribution or the weight distribution in a graph such as a curve or a histogram.