JPH0788007B2 - Humidity controller - Google Patents

Description

TECHNICAL FIELD The present invention relates to a humidity controller in a manufacturing plant of artificial sand used for concrete or the like, and is particularly excellent in quality control of manufactured artificial sand and prevention of environmental pollution. It relates to a humidity controller having an effect.

[Conventional technology]

Conventionally, artificial sand such as crushed sand manufactured by a dry method such as a crusher has been exported and stored in a dry state from a crushed sand manufacturing plant. Therefore, the crushed sand is a mixture of particles with a particle size of 5 mm or less at an appropriate ratio, that is, because it is close to natural sand, for example, when storing it in a storage tank or outdoor level ground, when making it pile up from a high place, Larger particles tend to flow away from the point of fall, whereas smaller particles tend to deposit relatively near the point of fall.

Therefore, in the stage of crushed sand, what had an artificially uniform particle size distribution artificially became uneven, and at the time of use it would not be the sand particle size distribution that was desired for concrete. Was occurring.

Further, when falling from a high place or during transportation, dust is generated due to natural wind, which may cause environmental pollution.

Furthermore, when the sand is exposed to the outdoor sun, it becomes a completely dry state, so that the amount of water increases during the production and kneading of fresh concrete, and the water-cement ratio tends to increase. That is, the apparent amount of water is increased by absorbing very fine dry fine powder adhering to the surface of the sand particles during the raw concrete kneading work, and as a result, the water-cement ratio increases and the cement It was uneconomical due to the increase of

[Problems to be Solved by the Invention]

As described above, when manufacturing crushed sand by a dry method, during the transportation of crushed sand and the stage of storage, when falling from a high place,
The crushed sand that had a uniform particle size distribution as a whole caused an uneven particle size phenomenon and separated into large and small particle sizes, and it was not possible to provide crushed sand with the particle size distribution required for ready-mixed concrete. .
Therefore, it has been strongly demanded to avoid these uneven graining and separation phenomena.

Further, it has been strongly desired to prevent the work environment from being polluted due to dust scattering when falling from a high place or during outdoor transportation.

Furthermore, no effective measure was found for preventing the water-cement ratio increase phenomenon due to water absorption during the mixing and mixing of raw concrete with dry fine powder.

[Means for Solving the Problems]

In order to solve the above-mentioned problems, the humidity control apparatus of the present invention is an apparatus for dry crushing and sieving the crushed sand after removing fine powder by dry classification to control the humidity, and through a spoke on a hollow rotating shaft. A drum is fixed in a concentric manner, a single or multiple screw is provided on the rotary shaft on the raw material charging side and the drum, and a rotary joint is connected to one end of the rotary shaft to provide a water absorption source. A water sprinkling nozzle for the rotary shaft of the screw portion was provided, a plurality of lifters were provided inside the central portion of the drum, and a wire mesh was provided on the discharge side of the raw material over the entire circumference of the drum.

[Work]

Dry crushing, sieving, dried crushed sand from which fine powder has been removed through the steps of dry classification is loaded into the humidity controller of the present invention,
It enters into the drum due to the rotational driving force of the feeding screw, and is further kneaded by the lateral feeding screw and is supplied with water from the injection nozzle to reach the middle portion of the drum. A lifter is rotating with the drum in the middle of the drum, and the water supplied by this scraping action is evenly distributed and conditioned in the crushed sand.
Eventually, it reaches the wire mesh portion on the drum discharge side, passes through this wire mesh, and is delivered to a storage location by a transportation means such as a belt conveyor. On the other hand, crushed particles and foreign substances (for example, dust and lump-shaped lumps formed by stone powder) having a size larger than the mesh that cannot pass through the wire net are eliminated via a separate foreign substance discharge chute.

〔Example〕

Hereinafter, details of embodiments according to the present invention will be described with reference to the drawings.

1 to 3 show an embodiment according to the present invention. FIG. 1 is an overall side sectional view, FIG. 2 is a transverse sectional view taken along the line II-II of FIG. 1, and FIG. It is a flow sheet of a crushed sand manufacturing plant including a wet machine.

The flow of the sand crushing plant will be described with reference to FIG. 3. Raw materials (crushed stones) are put into the service hopper 1, quantitatively cut out from the feed feeder 2, fed into the crushed sand crusher 4 by the belt conveyor 3, and crushed. It After that, it is put into the vibrating screen 6 by the conveyor 5 and screened. Those on the net are returned to the conveyor 3 again and crushed by the crushed sand crusher 4. The material under the net is put into the air separator 8 by the belt conveyor 7, and fine particles (stone powder of 0.15 mm or less) unnecessary for crushed sand are removed by airflow classification, and the dust tank (fine particles) by the screw conveyor 10 and the bucket elevator 11. Stone powder storage tank). On the other hand, the crushed sand from which the fine powder has been removed by the airflow classification enters the humidity controller 13 and is adjusted to an appropriate water content, that is, 3 to 5% relative to the weight of the crushed sand,
It is accumulated and stored via the belt conveyor 9.

Next, the structure and operation of the embodiment of the humidity controller according to the present invention will be described with reference to FIGS. 1 and 2.

The raw material (crushed sand) from which the fine powder has been removed by the air separation 8 is put into the feeding chute 101, and the hollow rotating shaft 102
It moves to the water sprinkling part A in the drum 7 by the feeding screw 104a attached to. 101a is an inspection hole. The drum 107 is pressed by the spokes 106 and the reinforcing member 107a so that the rotating shaft 102
Is concentrically fixed and rotates integrally with the rotating shaft 102. The rotating shaft 106 is a bearing 1 mounted on the mounts 111, 111 at both ends.
It is supported by 03 and 103, and is driven and rotated by a motor (not shown) via a chain wheel 115. The raw material that has entered the drum 107 is laterally fed by a single- or double-threaded horizontal feed screw 104b, and also passes through a water supply valve 113 that is connected to one end of the rotary shaft 102 via a rotary joint 112 and then is sprinkled. Water to be supplied into the drum 107 from the nozzle 114 is added, and the drum 107 is held by six lifters fixed to the inner surface of the drum of the kneading section B in the middle, repeatedly dropped and kneaded, and uniformly kneaded. After being made to have a water content, it is further transported to the discharge side. In the discharge section C, a wire mesh 10 is provided all around the entire surface of the drum.
8 is stretched, and the crushed sand of the raw material whose humidity has been adjusted in the kneading section B passes through the wire net 108 and is conveyed by the subsequent belt conveyor 9 via the receiving chute 109. On the other hand, crushed stones, dust, and foreign matter above the mesh of the wire net 108 are discharged through the foreign matter discharge chute 110 provided at the edge of the drum 107.

As described above, the crushed sand is conditioned by the humidity controller of the present invention to a uniform moisture content (3 to 5%) and then transported and stored.
Even when dropped from a high place, proper adhesion due to moisture is less likely to cause an uneven particle phenomenon, and since fine powder is removed in advance, environmental pollution due to scattering does not occur.

[Advantages of the Invention] The humidity controller of the present invention is a device for controlling the humidity after dry crushing, sieving, and dry classification to remove fine powder, and a drum is concentric with a hollow rotary shaft through spokes. It is fixed in the shape of a cylinder, and the rotary shaft and the drum are provided with a single- or double-threaded screw, and water is sprinkled by a scattering nozzle provided on the rotary shaft, kneaded by a lifter, and crushed sand is obtained by passing through a wire mesh. Since it is used in the production of fresh concrete in a uniform humidity control state where the attached water content is about 3 to 5%, it is possible to provide good fresh concrete with stable quality.

Further, it is less likely to cause environmental pollution such as uneven particle size and scattering of fine powder in the steps of transportation and storage after the humidity controller, which is advantageous in terms of maintenance.

In addition, as a result of uniform and proper humidity control, fine powder adhering to the surface of crushed sand is also properly absorbing water, so it is possible to keep the water-cement ratio at the time of the production of ready-mixed concrete small and reduce the cement usage fee. Economical efficiency is improved.

BRIEF DESCRIPTION OF THE DRAWINGS FIGS. 1 to 3 show an embodiment according to the present invention, FIG. 1 is an overall side sectional view, FIG. 2 is a transverse sectional view taken along the line II-II in FIG. FIG. 3 is a flow sheet (process diagram) of a crushed sand manufacturing plant including the humidity controller of the present invention. 1 ... Service hopper, 2 ... Cutting feeder, 3 ...
Belt conveyor, 4 crushed sand crusher, 5 conveyor, 6 vibrating screen, 7 belt conveyor, 8 air separator, 9 belt conveyor, 10 belt conveyor, 11 bucket elevator, 12 ... dust tank, 13 ... humidifier, 101 ... injection chute, 102 ... rotating shaft, 103 ... bearing, 104a ... injection screw, 104b ... transverse feed screw, 105 ... lifter, 106 ... spokes, 107
...... Drums, 108 …… Wire mesh, 109 …… Reception chute, 110
…… Foreign matter discharge chute, 111 …… Cross stand, 112 …… Rotary joint, 113 …… Water supply valve, 114 …… Sprinkling nozzle, 115 …… Chain wheel, 116 …… Safety cover, A …… Sprinkling section, B…
… Kneading section, C… Discharging section.

Claims (1)

[Claims] 1. A device for dry crushing and sieving crushed sand to remove fine particles by dry classification and then adjust the humidity, wherein a drum is concentrically fixed to a hollow rotary shaft through spokes to prepare a raw material. The rotating shaft and the drum on the charging side are provided with a single-thread or a double-thread screw, a rotary joint is connected to one end of the rotating shaft to provide a water supply source, and a water spray nozzle is provided on the rotating shaft of the screw portion A humidity controller characterized in that a plurality of lifters are arranged inside the central portion of the drum, and a wire net is provided on the discharge side of the raw material along the entire circumference of the drum.