JPS6340564B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to the creation of a moisture control method for fine-grained materials such as sand, which prevents moisture adhering to fine-grained materials such as sand from being bothered by intense airflow conditions in equipment and factories. The aim is to provide a method that allows for smooth adjustment without any problems.

River sand or similar fine-grained materials are so-called fine aggregates that are indispensable materials in today's various construction and civil engineering industries that utilize cement, and of course have been commonly used since ancient times. However, such fine-grained materials have adhering moisture, and this adhering moisture value usually fluctuates in a variety of ways and over a wide range. In other words, the source of such river sand is outdoors, such as a riverbed, and even if it is collected and deposited in a yard, there is hardly any special roofing, so it is difficult to collect or deposit it in a yard. Due to both transportation and storage conditions, there is an extremely high possibility that it will come into contact with river water or rain and dew.On the other hand, because of the fine grain size of sand, it has an extremely large specific surface area, and it is inevitable that it will contain water that adheres to the surface. Moreover, since the voids between these particles also retain moisture, the adhering moisture is always present, and moreover, it constantly changes depending on the weather conditions. For example, even if the sand is from the same production area and is considered to be the same deposit, the specific amount of water attached to the top and bottom of the sand is different, and the value measured in the morning and the amount measured at noon are different. The results are different from the previous results, and the range of variation is quite large. However, when preparing a cement mixture using this sand, the water-cement ratio (hereinafter referred to as W/C) and cement-sand ratio (hereinafter referred to as C/S), or when making concrete, the cement or sand Which is the mixing ratio of coarse aggregate G such as gravel to one or both (hereinafter referred to as S/G or C/G)
The strength and fluidity (formability,
It is clear that it has a serious effect on the workability of the workpiece. Excessive water content will cause separation and breathing in any case, and will be a major cause of a decrease in strength, while too little water content will cause separation and breathing. This impairs moldability and injectability, and even if auxiliary treatments such as continuous vibration and compression are used in combination, a dense structure cannot be formed, which also results in reduced strength and other product defects. Therefore, although it is essential to properly determine the W/C as described above in order to obtain a preferable product and achieve smooth injection molding, the amount of water attached to the sand used for it is In reality, the above-mentioned relationship cannot be properly determined because the situation fluctuates and cannot be accurately grasped and managed, and not only the W/C but also the S/C are uncertain. Of course, there are methods to measure the weight of this sand by drying it to an absolute dry state or measuring it in water, but this method is practical when a large amount of sand is required. In addition, the former consumes a large amount of heat energy and time, and the latter also requires a lot of man-hours to completely penetrate the water into the sand grains and release air (according to JIS, 24-hour immersion is required). ) and the amount of man-hours required to discharge the water contained therein increases considerably.

In order to dehydrate the surface of such granular materials, Japanese Patent Laid-Open Publication No. 1983-1989 discloses that the granular materials are scattered using wind power, and the water is dehydrated by the impact force of the scattered granular materials.
54358, but in this case it is clear that a considerably strong wind force is required, and it is natural that this wind force flows turbulently within the equipment casing and blows out around the equipment. The amount of force ejected from the typhoon alone is as strong as a typhoon, or even more so. In other words, if it were carried out inside a factory, it would blow through the factory like a typhoon, and even if it was carried out outdoors, it would blow away the surrounding earth and sand, making it difficult for workers to get close to the equipment. An even stronger pressure airflow is generated, and the behavior of the granular material after the impact is reversed is also disturbed, especially in the case of sand grains, the sand grains are blown out of the case by the airflow from the case.
The processing results will be greatly disturbed and the work itself will inevitably become unstable.

The present invention was devised after repeated studies and speculations in view of the above-mentioned circumstances, and it uses centrifugal force to scatter the fine aggregate such as sand as described above, and transfers these dispersed flying particles to a board. This method proposes collision with a surface, and the adhering moisture is transferred to the colliding plate surface by the impact force at the time of collision, and the adhering moisture is adjusted by causing the fine aggregate to fall backwards from the plate surface. In other words, if the above-mentioned particles are dispersed by centrifugal force, they will fly without creating a particularly strong whirlwind inside the case, and if they are subjected to impact under conditions where no strong wind force is applied inside the case, the Even if it is not possible to completely remove water from the particles during impact, the amount of water remaining in the particles is generally inversely proportional to the above-mentioned flight speed and centrifugal force, so by appropriately selecting the degree of centrifugal force, It is possible to make the amount of water attached to the sand grains that reversely fall from the impact plate approximately constant, and if the amount of water attached to the fine aggregate is made constant in this way, the above-mentioned W/C, C/S value or It is clear that it is possible to determine the amount of water to be added by properly understanding G/S and other factors, and that the quality of the resulting products can be stabilized and various cement products can be obtained without variation.

It should be noted that it is advantageous in terms of equipment and power to apply the centrifugal force to the sand grains using a rotating disk, which allows the sand grains supplied to the center of the rotating disk to be dispersed and expanded. It can be processed efficiently by letting it fly. In addition, since the water content of the sand grains themselves fluctuating as described above, the sand grains supplied onto such a rotating disk are supplied with water separately, and it is preferable to drain the excess water accordingly. It is preferable to supply the water in a uniform state in order to make the amount of water attached after the collision treatment more uniform.

An example of an apparatus for carrying out the method of the present invention as described above is as shown in FIG. A reception port 12 is formed in the center of the rotating disk 2, and a dispersing piece 7 is provided on the circumferential side thereof. The shaft cylinder 13 is attached to a fixed cylinder 14 with a bearing 3 interposed therebetween.
A belt is suspended between the pulley 15 attached to the lower part of the motor 4 and the pulley 5 of the motor 4, so that the pulley 15 is rotated at a required speed. However, an annular collision plate 6 is provided on the circumferential side of the rotating disk 2 as described above at an appropriate distance so as to be removably attached to the lower casing 10 as appropriate, and the lower casing has an inverted funnel shape. Below 10, another funnel-shaped receiving hopper 8 connects its receiving opening to the lower casing 1.
One end of the conveyor 11 faces the discharge port 18 of the receiving hopper 8, and collects the fine aggregate that has collided with the collision plate 6 and reversed and fallen. Hopper 8
It is designed to be collected and transported.

In some cases, the rotating disk 2 as described above may be shaped like a plate with its circumferential side bent slightly upward, and in this case, the sand grains will be scattered upward to a certain extent. However, even without specially arranging the dispersion piece 7, an effective centrifugal force can be imparted to the sand grains spread out on the two surfaces of the disk by combining the frictional action of the sand grains in the upward bending region when the sand grains are scattered and separated. can be achieved. However, in such a case, by making the downward inclination angle of the collision plate 6 suitably larger than in the case shown in the figure, the inverted sand grains can be preferably received into the hopper 8, and the same effect as described above can be achieved. can. In addition, a belt conveyor or the like may be installed in front of the hopper 1 to continuously feed sand grains, but a water supply pipe 16 may be attached to the outlet of the hopper 1, and a water supply pipe 16 may be installed at the outlet of the hopper 1 as necessary. A stirring mechanism such as a screw type or a ribbon type is provided to supply and mix water to the sand grains passing through the outlet, thereby equalizing the amount of water that lands on the sand grains.

Another embodiment of the adjusting device for carrying out the present invention is separately shown in FIG. The fact that the cylinder 13 is driven by the motor 4 is the same as that shown in FIG.
7, that is, cut the middle part of the casing 10 and fix the attached plate 18a to the outside of the cut part, make the part corresponding to the cut part a receiving part 17, and attach a collision plate to the receiving part 17. By accommodating the collision plate 6 and fixing it with a suitable stopper 19, the inner surface of the casing 10 is substantially smooth, and the stopper 19 can be removed to replace the collision plate 6 at any time. Note that the lower side of this casing 10 is a bulged portion 2.
0, and the receiver body 9 is housed in the bulge 20. The diameter of the receiver body 9 is within the bulge 20 of the casing 10, and the diameter of the receiver body 9 is within the extension line of the plate surface of the collision plate 6. As shown in the figure, the assembly is performed using a machine stand 22 located at a suitable distance 21 between the casing 10 and the casing 10. The fine grain material that is guided to the outside of the receiving body 9 through the inner surface of the enlarged part 20 and collides with the surface of the collision plate 6 falls completely into the receiving body 9 regardless of the existence of the gap 21. It is something that is present.

Although not shown in FIG. 2, a belt conveyor or the like is provided within or below the receiving body 9 in the same manner as shown in FIG. Of course, they may be carried out sequentially.

Specific examples of the method of the present invention as described above will be described below.

Example 1 Using the apparatus shown in Figure 1 of the accompanying drawings mentioned above, fine water-containing river sand (water absorption rate: 3.98%, water absorption rate: 3.98%,
The rotating disk 2 has a diameter of 1.28%).
Using a 400mm one, connect this rotating disk 2 to the motor 4.
The sand grains were rotated at a speed of 1100 revolutions per minute to cause the supplied sand grains to collide with the collision plate 6. The sand grain supply rate to hopper 1 is 50~ as water-containing sand.
The speed was varied within the range of 160 kg/min, but under the rotation conditions of the rotating disc 2 as described above, the conveyor 1
The sand carried out from No. 1 was sampled every minute and its content was measured, and the result was within the range of 9.4 to 10.1%, confirming that the amount of attached water was approximately constant.

Furthermore, when the rotational speed of the rotating disk 2 was set to 5000 revolutions per minute, which is higher than in the above case, under the same conditions as described above, the content measurement results regarding the sampling of sand carried out were 6.06 to 6.38%, and the adhesion It was confirmed that the water amount was lower and the variation range was stabilized within a narrower range.

Example 2 Using the same equipment as in Example 1, medium-sized sand produced in Kimitsu, Chiba Prefecture (water absorption rate 2.25%, coarse grain rate 2.28
%), in this case by adding 4 g of water per minute at the hopper outlet.

That is, at this time, under the rotation conditions of the rotating disk 2 shown in the first part of the above example, the water content of the obtained sample was 4.7 to 5.3%, and even under the same rotation conditions, the amount of water attached was low because it was medium-sized sand. However, it was confirmed that the range of variation was narrower.

Similarly, the sampled water content measured under the latter rotation conditions of Example 1 was 4.33 to 4.85%, and similar results with little variation could be obtained.

Example 3 Coarse sand produced in Fujikawa, Shizuoka Prefecture (water absorption rate 3.31%, coarse grain rate 2.96%) was treated in the same manner as in Example 2. In other words, the amount of water deposited when the rotation speed of the rotating disk is relatively low (1100 times/min) is 3.3 to 4.2%, and the amount of water deposited when the rotation speed is relatively high (5000 times/min) is: It was confirmed that the variation range of the amount of attached water was 3.2 to 3.52%, which was extremely small.

According to the present invention as explained above, the amount of water deposited varies in various ways, making it difficult to grasp the actual situation, and to accurately grasp this requires an unbearable amount of thermal energy or man-hours. It is possible to precisely adjust the moisture content of fine-grained materials such as dry sand without having to worry about severe turbulence or swirling flows caused by wind power, and to provide such materials with a small range of variation. The process is quick, and since it uses centrifugal force, the desired adjustment process can be performed smoothly with relatively little drive energy. This invention is highly effective and suitable as a management method for sand, etc., which is required for industrial use.

[Brief explanation of the drawing]

The drawings show embodiments of an apparatus for carrying out the method of the present invention, in which FIG. 1 is a partially cutaway side view of one example, and FIG. 2 is a partially cutaway side view of another embodiment. . In these drawings, 1 is a fine particle supply means, 2 is a rotating disk, 3 is a bearing, 4 is a motor, 5 is a pulley, 6 is a collision plate, 7 is a dispersion piece, 8 is a receiving hopper, and 10 is a lower part. In the casing, 11 is a conveyor, 12 is a receiving port, 13 is a shaft cylinder, 14 is a fixed cylinder, and 16 is a water supply pipe.

Claims (1)

[Scope of Claims] 1. Fine-grained material such as sand with adhering water is scattered by centrifugal force, and the fine-grained material scattered by centrifugal force collides with the board surface and is reversed, causing it to stick due to the impact force caused by the centrifugal force. A method for controlling moisture in fine grain materials such as sand, which comprises separating moisture from the particle surface and separating the water separated by the impact force from treated fine grain materials. 2. Regarding fine-grained materials such as sand as set forth in claim 1, in which water is further added to fine-grained materials such as sand containing various amounts of adhering water and then dispersed by centrifugal force. How to adjust moisture.