JPH10182202A - Production of fine aggregate for concrete and apparatus therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a process for producing fine aggregate for concrete from granular slag obtd. by treating solid waste or molten slag and an apparatus therefor. SOLUTION: The granular slag obtd. by treating the solid waste or the molten slag is supplied to a high-speed rotating drum 5 opened in the upper part. The frictional crushing of the granular slag is executed by friction, collision and press of particles against and to each other by rotation of this drum. The splashing granular slag is allowed to stagnate at an annular body 11 arranged on its outer peripheral edge and the similar frictional crushing is executed; further, the granular slag is fluidized in the space enclosed by the rotary drum 5 and the annular body 11, by which the fine aggregate for concrete is produced. The execution of fine granulating and spheroidizing is made possible while fine powder components are increased according to this process and, therefore, the fine aggregate for concrete having the desired characteristics is obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to granular slag obtained by melting solid waste products such as incinerated ash and sewage sludge and then quenching with water, or molten slag produced simultaneously with pig iron in a blast furnace using water, air, etc. The present invention relates to a method and an apparatus for producing fine aggregate for concrete using granular slag obtained by quenching by the method as a raw material.

[0002]

2. Description of the Related Art In recent years, solid waste such as incinerated ash of domestic waste and sewage sludge has been melted after being melted to secure a final disposal site and increase environmental protection. Volume reduction and harmlessness are achieved by quenching with water to obtain granular slag. Also,
Molten slag produced simultaneously with pig iron in a blast furnace is also treated similarly by rapidly cooling it to granular slag with water, air, or the like. Although the reduced volume and detoxified granular slag is partly crushed by an impact crusher such as a rod mill and crushed into fine particles, it is recycled as a material for the interlocking block. Most of these are dumped into landfills without being used, making it increasingly difficult to secure them.

[0003] One of the applicants pays attention to the situation of such granular slag and the fact that fine aggregate (sand), which is used in large quantities in concrete works such as construction works, is becoming scarce. Of a method for producing fine aggregate for concrete from granular slag obtained by treating various solid wastes, and filed Japanese Patent Application No. 6-15429 on June 14, 1994.
No. 2 (JP-A-7-330399) was filed for a patent.

The invention according to the prior application does not use instantaneous crushing of a granular slag by an impact crusher to reduce the size of the granular slag as in the case of recycling as a material for an interlocking block. The particles are rubbed with each other to make them fine using the friction between the particles, and the particles are made spherical in the range of a predetermined coarse particle ratio to be processed as a fine aggregate for concrete.

[0005] In the invention according to the above-mentioned prior application, a fine powder generated during the processing of granular slag is once separated, and the fine powder is returned to the processed slag particles and mixed. By comparing the fine aggregate for concrete manufactured by the equipment that implements this method with sand that has been used in the past, it was confirmed that the method was capable of replacing the entire amount of sand with the sand. Implementation is planned to play a part in the project. In addition, the second method, in which fine particles generated during processing of granular slag are not separated and increased as they are, to achieve finer particles and spheroidized particles, is equivalent to the particle size gradient of fine aggregate for concrete and has a surface similar to that of fine aggregate. Although it can be said that it is ideal as a method for processing a granular slag which is glassy, further improvement or contrivance was required to realize this method.

[0006]

Therefore, the inventors of the present invention have found that the particle size distribution of the granular slag and the suppression of the bleeding phenomenon when the granular slag is used as fine aggregate of concrete may be achieved by increasing the fine powder content. Based on the knowledge that the particles such as fine aggregates should be made spherical in order to reduce the mixing water at the time of casting and secure the required fluidity, implement the second method. As a result of intensive studies to achieve the desired effect, it was found that the intended purpose can be achieved by grinding and flowing granular slag using friction between particles and the like. That is,
In the present invention, the granular slag is dropped and supplied to a high-speed rotating drum having an open upper portion, and the particles are crushed by friction, collision, and pressing between the particles due to rotation of the rotating drum, and the granular slag is scattered by centrifugal force. The same grinding process is performed by staying in the annular body arranged on the outer peripheral edge,
Furthermore, by flowing these granular slags in the space surrounded by the rotating drum and the annular body, the fines are adjusted while the fine powder content is adjusted, and the slag is formed into a spherical shape within a predetermined coarse particle ratio. is there.

In this case, the granular slag is sieved to a size of 10 mm or less in consideration of the quality standard of the fine aggregate for concrete, and after removing foreign substances such as iron and supplied to a rotating drum, it is subjected to fluid grinding. Processing can be performed efficiently. Note that granular slag exceeding 10 mm is separated and crushed, and then used again after knotting.

Further, if the supply amount of the granular slag, the number of revolutions of the rotary drum, and the grinding time are controlled in accordance with the properties of the granular slag as a raw material and the fine aggregate for concrete as a product, the granular slag as a raw material can be obtained. The desired fine aggregate for concrete can be manufactured depending on the properties of the concrete.

On the other hand, as an apparatus for carrying out the method for producing a concrete fine aggregate according to the present invention, a high-speed rotating drum having an open upper portion for receiving granular slag, and an outer peripheral edge of the rotating drum are arranged in close proximity. And an annular body for retaining granular slag scattered by centrifugal force from the rotating drum, and friction and collision between particles in a space surrounded by the rotating drum and the annular body due to rotation of the rotating drum. The granulated slag is subjected to grinding by pressing and fluidized, so that the granular slag is refined while adjusting the fine powder content by such fluidized grinding so that the granulated slag is formed into a spherical shape within a predetermined coarse particle ratio. Configure.

In this case, if the height of the annular body is adjusted by the annular body height adjusting device, the grinding time can be easily adjusted.

The manufacturing apparatus includes a classifying device for classifying the particle size of the granular slag, a crushing device for crushing slag having a predetermined diameter or more classified by the classifying device, and a granular slag classified by the classifying device. It is preferable to include a supply device that supplies the rotary drum with a predetermined amount at a time, and a transmission device that continuously changes the rotation speed of the rotary drum.

Further, a first test analyzer for analyzing the properties of the granular slag as a raw material, a second test analyzer for analyzing the properties of the granular slag refined by the attritor, and a second test analyzer for analyzing the properties of the granular slag refined by the attritor. If there is provided control means for controlling the granular slag supply device, the transmission, and the annular body height adjusting device based on the analysis results of the test analyzer and the first test analyzer, a fine aggregate for concrete can be manufactured as desired. be able to.

According to the present invention, when the granular slag is dropped and supplied to the high-speed rotating drum, a self-lining layer is formed on the inner wall of the rotating drum by the granular slag adhered by centrifugal force due to the rotation of the rotating drum. If granular slag is further supplied in this state, the granular slag cannot catch up with the speed of the cell lining layer rotating together with the rotating drum, and a shearing phenomenon occurs between the layers of the granular slag. This phenomenon is a grinding action by friction, collision and pressing between the particles, and rubs the corners and vitreous surface to make the granular slag finer and spherical, thereby generating fine powder. Further, a part of the granular slag moves upward in the circumferential direction of the rotating drum and overflows and scatters while being subjected to a grinding action by a shearing phenomenon. The scattered granular slag is pressed against a self-lining layer similarly formed inside an annular body located at the outer peripheral edge of the rotary drum, and at this time also, grinding is performed. On the other hand, these granular slags flow in a space surrounded by the rotating drum and the annular body, and are subjected to fine grinding and spheroidizing processing by interaction with the grinding action, and fine powder generated by a series of fluid grinding actions. Is also adjusted.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, a method for producing a fine aggregate for concrete according to the present invention will be described in detail in relation to an apparatus.

FIG. 1 shows an embodiment of an apparatus for carrying out the method for producing fine aggregate for concrete according to the present invention, which is configured as an apparatus for processing a granular slag by grinding and flowing it. ing. That is, this grinding device has a hopper 3 for dropping and supplying granular slag at the upper part of the cylindrical main body 1, and a rotary drum 5 for receiving the granular slag is disposed below the discharge port 3 a of the hopper 3. Have been. In this embodiment, since it is assumed that the granular slag is charged in a wet state, the cylindrical main body 1 is formed as a closed type, and the inclination angle of the hopper 3 is set to 60 degrees or more, and the granular slag is set to 60 degrees or more. It is configured so that the slag shelf hanging phenomenon can be prevented.

The rotating drum 5 has a shape in which the upper part of the bottomed cylindrical body is opened and the central part protrudes upward, and the rotating drum 5 is connected to a rotating shaft 7 by a motor 9 shown in FIG. It is configured to rotate by a number.
On the outer peripheral edge of the rotary drum 5, an annular body 11 for receiving and retaining granular slag scattered by centrifugal force from the upper edge 5a of the opening of the rotary drum 5 is arranged in proximity. This annular body 11
Is a cylindrical upright wall 11a and a donut-shaped bottom 11b.
Are abutted at a substantially right angle so that the cross section thereof is substantially L-shaped. Donut-shaped bottom 1 of the annular body 11
1b is a bracket 1 protruding from the inner peripheral wall of the cylindrical main body 1.
3 and fixed in place by the upright wall 1
1a is a height adjusting device 15 disposed outside the cylindrical main body 1.
The height dimension (from bottom 11b to wall 11
a to the upper edge) can be adjusted as necessary.

In the present embodiment, the annular member 1
The distance between the upright wall portion 11a and the inner peripheral wall surface of the cylindrical main body 1 is set to 10 cm to 20 cm. If the separation distance is less than 10 cm, the processed granular slag may be clogged and clogged, and if the separation distance exceeds 20 cm, the outer diameter of the cylindrical main body 1 increases. This is unreasonable in terms of manufacturing cost and installation space.

Next, the operation of the grinding device having the above-described structure will be described. First, the granular slag charged into the hopper 3 slides down, and is dropped and supplied to the center of the rotating drum 5 through the discharge port 3a. The granular slag dropped and supplied adheres to the inner wall of the rotary drum 5 by centrifugal force generated by the rotation of the rotary drum 5, and initially forms a horn-shaped (tilted) cell flying layer. When the granular slag is further supplied in this state, the granular slag adheres to the inner wall of the rotary drum 5 in the same manner as described above. A shearing phenomenon occurs, and this shearing phenomenon acts as a grinding action due to friction, collision, and pressing between the particles, rubbing the corners of the granular slag and the vitreous surface to refine and spheroidize the slag, Generate a minute.

Further, since the angle of the cell lining layer adhered to the inner wall of the rotary drum 5 is kept substantially the same as the normal angle of repose, the continuously supplied granular slag is upward along the inclined surface. Then, while being accelerated in the circumferential direction while undergoing the grinding action by the above-mentioned shearing phenomenon, it overflows from the upper edge 5a of the opening of the rotary drum 5 and scatters outward by centrifugal force.

An annular body 11 is arranged close to the outer peripheral edge of the rotary drum 5. Inside the annular body 11, granular slag initially scattered similarly to the inner wall of the rotary drum 5 forms a self-lining layer. Due to the formation and stagnation, the granular slag overflowing from the upper edge 5a of the opening and scattered is pressed against the cell lining layer and ground, and at this time, the granular slag is also refined and spheroidized as described above. Processing is performed.

When the granular slag stays in the space surrounded by the rotating drum 5 and the annular body 11, a boundary surface is formed between the cell lining layer rotating with the rotating drum 5 and the staying granular slag. On the surface, friction is performed in a state where the weight of the retained granular slag is applied, so that intense grain refinement and spheroidization are performed. Also, the retained granular slag descends from the center so as to be entrained, and then rises along the rotating drum 5 and the self-lining layer formed on the annular body 11, and part of the slag rises upright wall portions 11 a of the annular body 11. Most of the material that overflows from the upper edge returns to the center of the rotating drum 5 again and exhibits a flow phenomenon, whereby the friction between the particles is evenly performed,
By this series of actions, grain refinement and spheroidization are performed in a state where the particle size gradient does not change much. In this way, the slag particles (milled slag) mixed with fine powder gradually overflow from the upper edge of the upright wall portion 11a of the annular body 11 and are discharged from a discharge port (not shown) as fine aggregate for concrete. Is done.

In this case, the accumulated amount of the granular slag (grinding time) is controlled by a height adjusting device 15 provided outside the cylindrical main body 1.
By controlling the height of the upright wall portion 11a, it can be controlled. Specifically, when the upright wall portion 11a is lowered, the amount of stagnation is reduced, and the grinding time is shortened.
Neither refinement nor spheroidization proceeds, but if the upright wall portion 11a is raised, the amount of retained particulate slag increases, the grinding time becomes longer, and refinement and spheroidization progress. The upright wall 11
If a is too high, appropriate grinding cannot be performed in relation to the angle of repose of the granular slag. Therefore, the annular body 11
If the grinding time is adjusted according to the height of the (upright wall portion 11a), the content of fine powder and the degree of granulation and spheroidization can be controlled. The granular slag having various properties can be adjusted to the actual loading rate, the coarse grain rate, and the fine powder content according to the properties and the use of the fine aggregate.

In the embodiment shown in FIG. 1, the rotary drum 5 and the annular body 11 are set as a single unit (one stage). However, when these are connected in series and the number of processing stages is increased, the fine powder content increases. As a result, the coarse grain ratio is reduced, and the actual product ratio can be increased.

FIG. 2 is an overall configuration diagram of a concrete fine aggregate manufacturing system using the grinding apparatus shown in FIG. That is, in this system, before the grinding device 35 shown in FIG. 1, a first test analyzer 21 for extracting a part of the raw material slag and analyzing its properties, the particle size of the raw material slag is 10 mm or less. Screen 25, a hammer crusher 27 for crushing granular (massive) slag having a particle size of more than 10 mm that has been classified by the vibrating screen, and magnetic particles such as iron pieces contained in the granular slag are removed. Magnetic separator 29, and further magnetic separator 2
A hopper 31 is provided for supplying granular slag from which magnetic particles have been removed by 9 to a feeder 33.

The feeder 33 for supplying a predetermined amount of the granular slag to the grinding device 35 includes a supply amount control device 33a that receives a control signal from the control panel 23 to adjust the supply amount. Here, the necessity of adjusting the supply amount will be described. When the supply amount of the granular slag is reduced, the grinding effect is improved, and when the supply amount is increased, the grinding effect is deteriorated. If the supply amount is too small, the granular slag will jump or break, resulting in a crushing state rather than grinding, and the spheroidization of the granular slag will not proceed, and only the fine powder content will increase. On the other hand, if the amount of supply is too large, the grinding time is short, the grain refinement and the spheroidization do not proceed, the power consumption increases, and the electric motor 9 becomes excessive. Therefore, it is necessary to adjust the supply amount of the granular slag in order to perform an effective and appropriate grinding process.

The annular body height adjusting device 15 attached to the grinding device 35 is configured to control the height of the annular body 11 (the upright wall portion 11a) by a control signal of a control panel 23 described later. The rotation speed of the electric motor 9 that rotates the rotating drum 5 is controlled by a rotation speed control device 39 such as an inverter, for example, in response to a control signal from the control panel 23. Here, the necessity of controlling the electric motor 9 to adjust the rotation speed of the rotary drum 5 will be described. In other words, the effect of the rotation speed of the rotary drum 5 on the grinding effect of the granular slag is slightly different depending on the model (a small model is slightly slower, and a large model is slightly faster). , 30 m / sec to 70 m / sec is most effective for the grinding action. However, if the rotation speed of the rotary drum 5 becomes too low, the contact pressure between the particles becomes small, and neither fine-graining nor spheroidization proceeds. On the other hand, if the rotation speed is higher than the predetermined value, the particles are crushed quickly, but the particles are crushed and spheroidization does not proceed, the power consumption increases, and the electric motor 9 becomes excessively large. Therefore,
It is necessary to control the electric motor 9 to adjust the number of revolutions of the rotary drum 5 to an appropriate value in order to appropriately make the granular slag trickle and spheroid.

In the subsequent stage of the grinding device 35, a second test analyzer 41 for taking out a part of the processed granular slag (fine aggregate) for testing and analyzing its properties,
A control panel 23 that outputs control signals to the annular body height adjustment device 15, the supply amount control device 33a, and the rotation speed control device 39 based on the analysis results of the test analysis device 21 and the second test analysis device 41 is arranged.

Next, a process of manufacturing a fine aggregate for concrete by the manufacturing system of the present embodiment configured as described above will be described. First, solid waste such as incineration ash and sewage sludge is melted (melting process), and quenched with water to rapidly cool granular slag that becomes raw material or molten slag that is produced simultaneously with pig iron in a blast furnace with water, air, etc. Thus, a granular slag as a raw material is obtained. Next, a part of the granular slag is extracted, and the first test analyzer 21 analyzes and measures properties such as a water absorption rate, an actual product rate, and a particle size. From the measurement results, the first test analyzer 21 supplies the optimum supply amount of the granular slag, the rotating speed of the rotary drum, and the height of the annular body to realize the predetermined properties required for the fine aggregate to be manufactured. The dimensions are determined, and the information is input to the control panel 23. First
The control panel 23 having obtained the information from the test analyzer 21 sends a control signal to the supply amount control device 33a, the annular body height control device 15 and the rotation speed control device 39 so that each control amount is optimized. Is sent.

The supply amount control device 33a, the annular body height control device 15 and the rotation speed control device 39 which have received the information from the control panel 23 determine the supply amount of the feeder 33 and the height of the annular body 11 based on the received information. And the number of rotations of the electric motor 9 is controlled. Granular slag as a raw material is supplied to the vibrating screen 25 and classified according to particle size.
Granular slag (lump slag) having a particle size exceeding 10 mm is fed to the hammer crusher 27 and finely crushed (crushing step). The granular slag crushed by the hammer crusher 27 is again supplied to the vibrating screen 25 and classified (classification step). The granular slag classified by the vibrating screen 25 is demagnetized by the magnetic separator 29 and supplied to the hopper 31 to be temporarily stored.

The granular slag stored in the hopper 31 is supplied to the grinding device 3 by a predetermined amount by a feeder 33.
5 is supplied. The granular slag supplied to the grinding device 35 is dropped and supplied to the rotating drum 5 that rotates at a high speed, and the granular slag supplied and dropped is formed on the rotating drum 5 and the annular body 11 as described with reference to FIG. The particle size gradient is hardly changed by a synergistic effect of a grinding action by friction, collision and pressing and a flow action in a space surrounded by the rotating drum 5 and the annular body 11 due to a shearing phenomenon generated between the self-layered layer and the cell flying layer. Granulation and spheroidization are performed to generate an appropriate amount of fine powder.

The slag particles subjected to the flow grinding process in this way overflow the upright wall portion 11a of the annular body 11, and are discharged as fine concrete aggregate. In addition,
A part of the fine aggregate is extracted and the second test analyzer 41 analyzes and measures properties such as a water absorption rate, an actual product rate, and a particle size.
If the predetermined properties required for the fine-grained material to be manufactured are not obtained from the measurement results of the second test analyzer 41, in order to realize the required properties, the granular slag is In order to re-determine the supply amount, the rotation speed of the rotary drum, and the height of the annular body, and to change the control amounts of the supply amount control device 33a, the annular body height control device 15, and the rotation speed control device 39, the control panel 23 Enter that information. Through the above series of processes, a desired fine aggregate for concrete is manufactured from the granular slag.

In the above-mentioned manufacturing system, the rotating drum 5 of the grinding device 35 and the annular body 9 are formed as one set (one stage). However, by connecting them in series to form a plurality of stages, the height of the annular body is increased. You can get the same effect as adjusting the
Also, by changing the control for each step, it is possible to produce high-quality fine aggregate for concrete.

Also, in this manufacturing system, an example is shown in which two analyzers, a first test analyzer and a second test analyzer, are used. However, both the first test analyzer and the second test analyzer are used. It is also possible to use one test analyzer having the function of, and further use a trommel in place of the vibrating screen 25, and use a vibratory feeder, belt feeder, screw feeder, rotary feeder or rotary valve as a feeder. May be used.

Next, the results of an experiment in which fine aggregate was actually produced from granular slag using the production system shown in FIG. 2 will be described. The experimental conditions are as follows. Throughput 6t / hr Rotational speed 2,290r. p. m. (Circumferential speed 50m / se
c. 1) The height of the annular body is 130 mm. The number of processing stages is three. Here, the number of processing stages is three, as shown in FIG.
And the annular body 9 are combined to form a single stage, which is connected in series in three stages.

1. Regarding the improvement of particle size The particle size distribution of the granular slag before processing, the fine aggregate for concrete obtained by the present invention, and the fine aggregate obtained by crushing the granular slag with a vibration mill were compared [see FIG. The shaded area surrounded by two thin broken lines (fine aggregate standard grain size) in the figure is the range of the standard grain size of the fine aggregate for concrete, and is included in this shaded area to satisfy the grain size requirement for fine aggregate. Need to be done]. As is clear from FIG.
The particle size gradient of the fine aggregate slightly coarser than the standard particle size is compared to the granular slag as a raw material that is almost equivalent to this standard particle size.
The fine aggregate for concrete obtained by the manufacturing system according to the embodiment falls within the range of the standard particle size of the fine aggregate while moving almost in parallel with the particle size gradient of the granular slag. This indicates that the particle forces of both large and small sizes were each reduced to the same degree. On the other hand, the fine aggregate obtained by the crushing of the vibration mill has a steep particle size gradient and exceeds the standard particle size of the fine aggregate, which indicates that it is not suitable for fine aggregate for concrete.

2. Regarding the formation of spherical (circular) particles, the granular slag before processing, the fine aggregate for concrete obtained by the present invention, the fine aggregate obtained by crushing the granular slag with a vibration mill, and the circular shape of natural mountain sand The degree coefficients were compared (see FIG. 4). The circularity coefficient is a secondary evaluation value. The degree of circularity is calculated by the equation (4πA / L ² ) based on the circumference (L) and the area (A) of the particle. (In this case, 1.0 for a circle,
The value becomes smaller as the shape becomes flat ellipse or irregular shape).
As is clear from FIG. 4, the spherical aggregate improving effect of the fine aggregate for concrete obtained by the present invention is remarkable, and it is understood that the fine aggregate is more spherical than natural mountain sand. This indicates that all particles were processed by rubbing against each other. On the other hand, fine aggregate obtained by crushing with a vibration mill
Since the particles are instantaneously broken into fine grains, corners are generated, and the improvement in the grain shape is inferior.

3. Regarding the actual loading rate The granular slag before processing, the fine aggregate for concrete obtained by the present invention, the fine aggregate obtained by crushing the granular slag with a vibration mill, and the natural pile sand The moments were compared (see FIG. 5). The actual product ratio is a numerical value calculated by a volume ratio of particles filled per unit volume, and is an overall evaluation index of both the particle shape and the particle size. The more they are properly mixed, the larger the actual product ratio becomes.
As is clear from FIG. 5, the actual percentage of the fine aggregate for concrete obtained by the present invention is a remarkably large value (70% or more) as compared with other materials. It can be seen that the system is suitable for the production of fine aggregate.

As described above, according to the present embodiment, the fine bone for concrete satisfying the condition of the actual loading rate (66% or more) that the particle size distribution is within the range recommended by the Japan Society of Civil Engineers and is desirable. It became clear that wood could be obtained. In addition,
As fine aggregate produced from granular slag, in addition to the above conditions, it is preferable to satisfy the conditions of a fine powder content of 0.15 mm or less of 5 to 20% and a coarse particle ratio of 1.9 to 3.1, According to the present embodiment, the above conditions can be easily satisfied by controlling each device by the control panel 23. From these facts, the fine aggregate manufactured according to the present embodiment can be used as a material which can completely replace the conventionally used sand.

FIG. 6 is a diagram showing a main part of a grinding device used in another embodiment of the present invention. In this embodiment, the rotating drum 51 has a stepped bottom. According to the rotating drum 51, the granular slag moving or flowing on the inner surface of the drum outwardly flows back and forth on the stepped bottom portion, so that the residence time becomes longer and efficient grinding can be performed. it can.

FIG. 7 is a view showing a main part of a grinding device used in another embodiment of the present invention. In this embodiment, the annular body 53 is formed in a U-shaped cross section. According to the annular body 53, the granular slag scattered from the rotating drum and entering the annular body collides with the upper piece 53a of the annular body 53 and returns to the opening, so that the slag stays in the annular body 53. The time becomes longer and efficient grinding becomes possible.

FIG. 8 is a view showing a main part of a grinding device used in another embodiment of the present invention. In this embodiment, the rotating drum 51 has a stepped bottom, and the annular body 53 is formed in a U-shaped cross section. That is, it has both functions shown in FIGS. 6 and 7,
Compared to the one shown in FIG. 1, the residence time of the granular slag in the rotating drum 51 and the annular body 53 is longer, and the effect of grinding is further enhanced.

FIG. 9 is a view showing a main part of a grinding device used in another embodiment of the present invention. In this embodiment, the annular body 55 is formed in a U-shape in cross section, and is fixed to the bracket with its opening inclined so as to face the rotating drum 51. When the annular body 55 is inclined in this manner, the granular slag flows without staying in the annular body 55 and returns to the rotating drum 51, and the residence time in the space surrounded by the annular body 55 and the rotating drum 51 is reduced. It becomes longer, and the effect of attrition becomes even higher.

FIG. 10 is a view showing a main part of a grinding device used in another embodiment of the present invention. In this embodiment, the annular body 57 is formed in a U-shaped cross section, and is directly fixed to the bracket. According to this annular body 57,
Since the granular slag scattered from the rotating drum and entering the annular body is returned to the annular body 57, the residence time in the annular body 57 is lengthened, and efficient grinding can be performed.

[0044]

As described above, according to the present invention, the granular slag dropped and supplied to the high-speed rotating drum having an open upper portion is used to reduce friction between particles caused by rotation of the rotating drum, collision between the particles, and the like.
Grinding using pressing is performed, and granular slag scattered by centrifugal force is retained in an annular body arranged on the outer peripheral edge of the rotating drum to perform similar grinding processing, and further surrounded by the rotating drum and the annular body By flowing these granular slags in the space to be formed, the granular slags are finely adjusted while adjusting the fine powder content of the granular slags and are sphericalized within a predetermined range of coarse particle ratio. Fine aggregate for concrete having desired properties can be produced using granular slag as a raw material.

The granular slag is sieved to a size of 10 mm or less and supplied to a rotating drum.
An efficient grinding operation can be realized.

Further, the supply amount of the granular slag, the number of revolutions of the rotary drum, and the grinding time are controlled in accordance with the properties of the granular slag as a raw material and the fine aggregate for concrete as a product. Regardless of the properties of the granular slag, a fine aggregate for concrete having desired properties can be produced.

Further, since the apparatus for adjusting the height of the annular body is provided, the residence time of the granular slag is adjusted according to the properties of the granular slag as the raw material and the specifications of the fine aggregate for concrete as the product. be able to.

Furthermore, a first test analyzer for analyzing the properties of granular slag as a raw material, a second test analyzer for analyzing the properties of pressurized granular slag, and the first test analyzer Control means for controlling the granular slag supply device, the transmission, and the annular body height adjusting device based on the analysis results of the second test analyzer are provided, so that the desired concrete fineness can be obtained regardless of the properties of the granular slag used as a raw material. Aggregate can be manufactured.

[Brief description of the drawings]

FIG. 1 is an explanatory view of a main part of a grinding device, which is an embodiment of an apparatus for performing a manufacturing method according to the present invention.

FIG. 2 is an overall view of a system for producing fine aggregate for concrete from granular slag using the grinding apparatus of FIG. 1;

3 is a diagram showing the particle size distribution of fine aggregate for concrete obtained by the manufacturing system of FIG. 2, granular slag before processing, and fine aggregate obtained by crushing the granular slag with a vibration mill. .

4 is a graph showing circularity coefficients of fine aggregate for concrete obtained by the manufacturing system of FIG. 2, granular slag before processing, and fine aggregate obtained by crushing the granular slag with a vibration mill. .

5 is a graph showing actual aggregate rates of fine aggregate for concrete obtained by the production system of FIG. 2, granular slag before processing, and fine aggregate obtained by crushing the granular slag with a vibration mill. .

FIG. 6 is an explanatory view of a main part showing another embodiment of the grinding device shown in FIG. 1;

FIG. 7 is an explanatory view of a main part showing another embodiment of the grinding device shown in FIG. 1;

FIG. 8 is an explanatory view of a main part showing another embodiment of the grinding device shown in FIG. 1;

FIG. 9 is an explanatory view of a main part showing another embodiment of the grinding device shown in FIG. 1;

FIG. 10 is an explanatory view of a main part showing another embodiment of the grinding device shown in FIG. 1;

[Explanation of symbols]

 Reference Signs List 1 cylindrical main body 5, 51 rotating drum 9 electric motor 11, 53, 55, 57 annular body 15 annular body height adjusting device 21 first test analyzer 23 control panel 25 vibrating screen 27 hammer crusher 29 magnetic separator 33 feeder 33a supply amount control Device 35 Grinding device 39 Rotation speed control device 41 Second test analyzer

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Kanichi Takayama 2-1 Shiraishi-cho, Kawasaki-ku, Kawasaki-shi, Kanagawa Japan Co., Ltd. (72) Inventor Wakiro Nishikori 2-7 Higashi-Nukicho, Tsuchiura-shi, Ibaraki Tetra Co., Ltd. (72) Inventor Kenji Hori 2-7 Togashi-cho, Tsuchiura-city, Ibaraki Pref. Tetra Co., Ltd. (72) Inventor Toshiyuki 2-7 Togashi-cho, Tsuchiura-shi, Ibaraki Pref.

Claims (7)

[Claims] 1. A granular slag obtained by melting solid waste such as incineration ash or sewage sludge and then quenching it, or a granular slag obtained by quenching molten slag produced simultaneously with pig iron in a blast furnace as a raw material, The granular slag was dropped and supplied to a high-speed rotating drum with an open top, and the particles were crushed by friction, collision and pressing between the particles due to the rotation of the rotating drum, and the granular slag scattered by centrifugal force was arranged on the outer peripheral edge thereof. The same grinding process is performed while being retained in the annular body, and the granular slag is further fluidized in a space surrounded by the rotating drum and the annular body. A method for producing a fine aggregate for concrete, comprising granulating and spheroidizing in a range of a predetermined coarse particle ratio. 2. The method for producing fine aggregate for concrete according to claim 1, wherein the granular slag is sieved to a size of 10 mm or less, and then foreign substances such as iron are removed and supplied to a rotary drum. 3. The supply amount of the granular slag, the number of revolutions of the rotary drum, and the grinding time are controlled according to the properties of the granular slag as a raw material and the fine aggregate for concrete as a product. The method for producing a fine aggregate for concrete according to claim 1 or 2. 4. An upper portion for receiving granular slag obtained by melting solid waste such as incineration ash and sewage sludge and then quenching it, or quenching molten slag produced simultaneously with pig iron in a blast furnace. A high-speed rotating drum having an opening, and an annular body that is disposed close to the outer peripheral edge of the rotating drum and retains granular slag scattered by centrifugal force from the rotating drum, and the rotating drum is rotated by rotation of the rotating drum. In the space surrounded by the annular body, grinding and grinding of the granular slag by friction, collision and pressing between the particles are carried out and fluidized, while fine grinding while adjusting the fine powder content by such fluid grinding An apparatus for producing fine aggregate for concrete, wherein the apparatus is formed into a sphere in a range of a predetermined coarse particle ratio. 5. The apparatus for producing fine aggregate for concrete according to claim 4, further comprising an annular body height adjusting device for adjusting the height of the annular body. 6. A classifying device for classifying the particle size of granular slag, a crushing device for crushing slag having a predetermined diameter or more classified by the classifying device, and a rotating drum for each of a predetermined amount of the granular slag classified by the classifying device. 6. The apparatus for producing fine aggregate for concrete according to claim 4, further comprising: a supply device for supplying the oil to the carcass; and a transmission device for continuously changing the rotation speed of the rotary drum. 7. 7. A first test analyzer for analyzing properties of granular slag as a raw material, a second test analyzer for analyzing properties of processed granular slag, a second test analyzer and a first test analyzer. The apparatus for producing a fine aggregate for concrete according to claim 6, further comprising control means for controlling the granular slag supply device, the transmission, and the annular body height adjusting device based on the analysis result of the test analysis device.