Sand drying and screening device

Abstract

To provide a sand drying and screening device that dries collected sand and further screens the sand according to its particle size.SOLUTION: A sand drying and screening device for drying and screening sand, includes: a first feed pipe into which supplied sand flows; a first hot air blower which sends heated air from the upstream side of the first feed pipe into the first feed pipe to move the sand in the downstream direction of the first feed pipe; a second feed pipe which is disposed in the vertical direction, opened downward, in which the first feed pipe communicates with the side peripheral surface of the second feed pipe, and the sand flowing into the second feed pipe from the side peripheral surface of the second feed pipe swirls and falls while flowing inside the second feed pipe; and a screening pipe which is connected vertically to the second feed pipe, has a filter that screens the sand flowing in from the second feed pipe according to its particle size, and discharges the sand that passes through the filter.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a sand drying and sorting device for drying the collected sand and further sorting the sand according to its particle size.

Background Art

[0002] When collecting sediment in water and sorting gravel with a predetermined particle size or more, conventionally, water containing sediment is pumped up by a pump, and the sediment contained in the pumped-up water is applied to a shaking device having a mesh, for example, to sort and separate gravel with a predetermined particle size or more.

[0003] As disclosed in Patent Document 1, the inventor of the present application has advanced the research and development of an instrument for sorting gravel contained in sediment without using a large-scale device, and has invented a gravel sorting tool that can more simply and efficiently sort gravel with a predetermined particle size or more from sediment contained in water.

[0004] The sorted gravel is dried, for example, so that the water content ratio becomes a predetermined ratio (for example, 5% or less) in order to be used as an aggregate such as concrete or asphalt or a construction material. For example, the sand is dried by a known rotary sand drying device. A general rotary sand drying device rotates a cylindrical container and sends hot air into the container, and dries the sand while stirring the sand in the container.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] The inventor of the present application has been engaged in the research and development of a new sand drying device for drying the collected sand, drying the sand more simply and efficiently, and further, in the drying process, a sand drying and sorting device capable of sorting sand according to its particle size has been developed.

[0007] Therefore, an object of the present invention is to provide a sand drying and sorting device for drying the collected sand and further sorting the sand according to its particle size.

Means for Solving the Problems

[0008] The sand drying and sorting device of the present invention for achieving the above object is a sand drying and sorting device for drying and sorting sand, and includes a first feed pipe into which the supplied sand flows, a first hot air blower that sends heated air into the first feed pipe from the upstream side of the first feed pipe and makes the sand flow in the downstream direction of the first feed pipe, and a second feed pipe that is arranged in the vertical direction and opens downward. The first feed pipe communicates with the side peripheral surface of the second feed pipe, and the sand flowing into the second feed pipe from the side peripheral surface of the second feed pipe falls while swirling in the second feed pipe. The second feed pipe, and a sorting pipe connected to the second feed pipe in the vertical direction, the sorting pipe having a filter for sorting the sand flowing in from the second feed pipe according to its particle size, and discharging the sand passing through the filter.

[0009] Further, another configuration of the sand drying and sorting device of the present invention is a sand drying and sorting device for drying and sorting sand, and includes a first feed pipe whose upstream end branches into two branches. Compressed air is supplied from the tip port of one of the two branches of the first feed pipe, and sand is sucked in by the flow of the compressed air from the tip port of the other of the two branches of the first feed pipe. The first feed pipe, and the upstream Compress air is sent into the first feed pipe from the side, and a compressor that causes sand to flow in the downstream direction of the first feed pipe, and a second feed pipe that is arranged vertically and opens downward, wherein the first feed pipe communicates with the side circumferential surface of the second feed pipe, and sand that has flowed into the second feed pipe from the side circumferential surface of the second feed pipe falls while swirling in the second feed pipe and flows, the second feed pipe, and a sorting pipe that is connected vertically to the second feed pipe, the sorting pipe having a filter that sorts the sand flowing in from the second feed pipe according to its particle size, and discharging the sand that has passed through the filter.

Advantages of the Invention

[0010] According to the sand drying and sorting device of the present invention, the operation steps of drying the collected sand and further sorting the sand according to its particle size can be carried out in one go, and the drying and sorting processes after the sand collection operation are significantly improved in efficiency.

Brief Description of the Drawings

[0011]

Figure 1

Figure 2

Figure 3

Figure 4

Embodiments for Carrying Out the Invention

[0012] Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, such embodiments do not limit the technical scope of the present invention.

[0013] FIG. 1 is a diagram showing an example of the overall configuration of a sand drying and sorting apparatus according to an embodiment of the present invention. In FIG. 1, a sand drying and sorting apparatus 10 includes a first feed pipe 11 into which the supplied sand flows, a first hot air blower 13 that sends heated air into the first feed pipe from the upstream side of the first feed pipe and causes the sand to flow in the downstream direction of the first feed pipe 11, a second feed pipe 14 arranged in the vertical direction and opening downward, and a sorting pipe 15 connected to the second feed pipe 14 in the vertical direction.

[0014] The first feed pipe 11 communicates with the side peripheral surface of the second feed pipe 14, and the sand that has flowed into the second feed pipe 14 from the side peripheral surface of the second feed pipe 14 falls while swirling in the second feed pipe 14 and flows. Further, the sorting pipe 15 has a filter 15a that sorts the sand flowing in from the second feed pipe 14 according to its particle size, and discharges the sand that passes through the filter 15a.

[0015] The first feed pipe 11 is an elongated pipe body that connects the sand storage tank 12 and the second feed pipe 14, and the sand stored in the sand storage tank 12 is sent to the second feed pipe 14 through the first feed pipe 11.

[0016] The sand storage tank 12 is a sand storage where the sand collected at a separated location is transported and stored. The sand in the sand storage tank 12 is usually stored in a state containing moisture.

[0017] The first hot air blower 13 is connected to the upstream end of the first feed pipe 11, and the sand in the first feed pipe 11 flows in the downstream direction due to the air volume and air pressure of the heated air (hot air) from the first hot air blower 13. The hot air blower is a hot air generating device that generates heated air (hot air) and sends it as air. The sand flowing in the first feed pipe 11 is dried while flowing due to the air pressure of the heated air. The heat source of the hot air blower 13 can be various, such as an electric heater or gas.

[0018] Preferably, at least a part of the path of the first feed pipe 11 has a scattering mechanism portion 111 that causes the sand flowing inside to scatter while flowing.

[0019] FIG. 2 is a diagram showing a configuration example of the scattering mechanism unit 111. FIG. 2(a) is a schematic longitudinal section, and FIG. 2(b) is a schematic plan view or bottom view. The scattering mechanism unit 111 has, for example, a double-tube structure composed of an outer tube 111a and an inner tube 111b. In the inner tube 111b, a plurality of protrusions 111c protruding into the inner tube and a plurality of openings 111d arranged close to each protrusion 111c are provided at predetermined intervals in the longitudinal direction. The sand flowing in the inner tube 111b hits the protrusions 111c and is diffused, and a part of it spreads from the openings 111d to the outer tube 111a side and flows. The protrusions 111c are appropriately arranged so that the flow resistance does not become too large, and while maintaining a predetermined flow rate of the sand, the sand is scattered. By scattering the sand, the surface area of the sand grains exposed to the hot air increases, and the drying of the sand by the flow is promoted.

[0020] The configuration of the scattering mechanism unit 111 is not limited to the example in FIG. 2, and can be determined according to the flow of the sand, such as the shape and size of the protrusions, the size and arrangement of the openings, etc. Also, it does not have to be a double-tube structure having the protrusions and openings illustrated in FIG. 2.

[0021] For example, it may be a tube body that generates a predetermined fluid resistance called a so-called Tesla valve. As a function of the scattering mechanism unit 111, by giving a certain degree of fluid resistance to the flow of the sand, the sand is scattered, and by increasing the contact area where the sand touches the heated air, it can be effectively dried. On the other hand, if the fluid resistance is increased too much, the flow of the sand will be blocked, so the scattering mechanism unit 111 is designed and arranged within the range where the flow of the sand is maintained.

[0022] If the air volume and air pressure provided by the first hot air blower 13 are insufficient to maintain a sufficient flow of sand, a compressor (not shown) may be connected to the branch pipes 18 (18a, 18b) provided in the middle of the first feed pipe 11, and compressed air may be fed from the compressor. The branch pipes 18 (18a, 18b) are normally closed by air valves. When the compressor is connected, the air valves are opened, and compressed air is supplied from the compressor to the first feed pipe 11. For example, when the length of the first feed pipe 11 is relatively long and sufficient air volume cannot be sent to the downstream side only by the supply of hot air from the upstream end, the supply of compressed air by the compressor can supplement the air volume and air pressure provided by the first hot air blower 13. In FIG. 1, an example of providing branch pipes 18a and 18b at two locations is shown, but the position and number of the branch pipes can be designed as appropriate.

[0023] The second feed pipe 14 is a pipe body arranged in the vertical direction and opening downward, and is formed with a conical portion that tapers downward. The first feed pipe 11 communicates with the connection opening 14a on the side peripheral surface of the second feed pipe 14. The sand flowing into the second feed pipe 14 from the side peripheral surface of the second feed pipe 14 flows through the second feed pipe 14 by falling into the lower opening 14c while swirling inside the second feed pipe 14. That is, the second feed pipe 14 functions as a powder separation mechanism (so-called cyclone structure) using centrifugal force, and the fine particles contained in the sand are discharged from the fine particle discharge port 14b without falling. Also, by more effectively exposing the sand to the dry heated air during the process of the sand falling in a spiral shape, the sand can be dried more efficiently while being transported.

[0024] The sand that has fallen into the second feed pipe 14 flows into the sorting pipe 15 from the lower opening 14c of the second feed pipe 14, and is sorted according to its particle size by the mesh filter 15a arranged in the sorting pipe 15.

[0025] Filter 15a is a member with mesh-like or net-like gaps such as a mesh-shaped wire mesh or punching metal, and the size of the gravel to be sorted is set according to the size of the gaps between them. For example, when it is desired to sort gravel with a particle size of 2 mm or more as the set particle size, a filter 15a with a gap interval of 2 mm is arranged on the cross-section inside the sorting pipe 15. Sand with a particle size below a predetermined threshold value (for example, 2 mm) that passes through the filter 15a is collected in the sand tank 17, and sand with a particle size exceeding the predetermined threshold value (for example, 2 mm) that does not pass through the filter 15a is discharged from the oversized discharge port 15b or is discharged, and the sand is sorted according to its particle size. The gap interval of the mesh of the filter 15a is determined according to the particle size of the sand to be sorted, such as 2 mm, 1 mm, 0.6 mm, etc.

[0026] Also, a second hot air blower 16 for blowing hot air onto the sand that has passed through the filter 15a may be installed. The hot air blower is arranged at a necessary position so that the sand accommodated in the sand tank 17 becomes dry sand with a predetermined water content ratio (for example, 1%) or less. The second hot air blower 16 is arranged to supply hot air from the side surface in the flow direction of the sand, scatters the flow of the sand falling in the sorting pipe 15, efficiently applies the hot air, and surely dries the sand.

[0027] FIG. 3 is a diagram showing another configuration example of the sand drying and sorting device according to the embodiment of the present invention. In the sand drying and sorting device 10A of the other configuration example shown in FIG. 3, in comparison with the configuration example of FIG. 1, the upstream end of the first feed pipe 11 has a branch pipe structure, a branch pipe 19 is connected, and a compressor 20 for supplying compressed air to one of the bifurcated tip ports 19a of the branch pipe 19 is connected (it may be connected via an extension hose or the like), and the other bifurcated tip port 19b is arranged in direct contact with the sand at the sand collection site (it may be arranged in contact with the sand via an extension hose or the like). The sand is directly sucked and collected from the sand collection site.

[0028] When compressed air is fed from the compressor 20 into one of the two outlets 19a of the branch pipe 19, a negative pressure is created by the Venturi effect in fluid dynamics. That is, the other outlet 19b of the two branches of the branch pipe 19 becomes a negative pressure, generating a suction force. Sand is sucked in from the other outlet 19b of the branch pipe 19 and fed into the first feed pipe 11. The supply amount of the compressed air from the compressor 20 can be adjusted by an air valve. The flow of sand after the first feed pipe 11 is the same as the configuration shown in FIG. 1. In the case of the sand drying and sorting device 10A in FIG. 3, since relatively dry sand is sucked in, the scattering mechanism part 111 shown in the configuration of FIG. 1 does not necessarily have to be provided in the first feed pipe 11. Of course, the scattering mechanism part 111 may be arranged. Also, the arrangement of the second hot air blower 16 is arbitrary. Since sand is collected by sucking it from the sand collection site, the sand storage tank 12 does not necessarily have to be provided. Note that FIG. 4 is a photograph showing a configuration example of the branch pipe 19.

[0029] The present invention is not limited to the above-described embodiments, and various modifications and changes that can be conceived by those having ordinary knowledge in the field of the present invention are included in the present invention as long as they do not depart from the gist including such modifications.

Explanation of Reference Numerals

[0030] 10, 10A: Sand drying and sorting device, 11: First feed pipe, 111: Scattering mechanism part, 12: Sand storage, 13: First hot air blower, 14: Second feed pipe, 15, Sorting pipe, 15a: Filter, 16: Second hot air blower, 17: Sand tank, 18(18a, 18b): Branch pipe, 19: Branch pipe, 20: Compressor

Claims

1. In a sand drying and sorting device for drying and sorting sand, a first feed pipe into which the supplied sand flows; a first hot air blower that sends hot air into the first feed pipe from the upstream side of the first feed pipe and causes the sand to flow in the downstream direction of the first feed pipe; a second feed pipe arranged in the vertical direction and opening downward, wherein the first feed pipe communicates with the side peripheral surface of the second feed pipe, and the sand flowing into the second feed pipe from the side peripheral surface of the second feed pipe falls and flows while swirling in the second feed pipe, the second feed pipe; a sorting pipe connected to the second feed pipe in the vertical direction, having a filter for sorting the sand flowing in from the second feed pipe according to its particle size, and the sorting pipe for discharging the sand passing through the filter, a sand drying and sorting device characterized by comprising.

2. The sand drying and sorting device according to claim 1, wherein the first feed pipe has a scattering mechanism portion for causing the sand flowing in the pipe body to flow while scattering.

3. The sand drying and sorting device according to claim 1, further comprising a tank for storing the collected sand, and the sand stored in the tank is supplied to the first feed pipe.

4. A compressor for sending compressed air into the first feed pipe is connected to a branch pipe branching from the middle of the first feed pipe, and the sand is caused to flow in the downstream direction of the first feed pipe by the compressed air supplied from the compressor, the sand drying and sorting device according to claim 1.

5. The sand drying and sorting device according to claim 1, wherein the second feed pipe has a discharge port for discharging fine particles of sand that float without falling among the sand flowing in from the first feed pipe.

6. The sand drying and sorting device according to claim 1, wherein the second feed pipe is formed to have a conical portion that tapers downward.

7. The sand drying and discrimination device according to claim 1, wherein the sorting pipe has a discharge port for discharging the sand that does not pass through the filter among the sand flowing in from the second feed pipe.

8. The sand drying and sorting device according to claim 1, further comprising a second hot air blower for blowing hot air onto the sand passing through the filter.

9. In a sand drying and sorting device for drying and sorting sand, A first feed pipe with an upstream end bifurcating into two branches, compressed air being supplied from the tip port of one of the two branches of the first feed pipe, and sand being sucked in by the flow of the compressed air from the tip port of the other of the two branches of the first feed pipe, the first feed pipe; A compressor that sends the compressed air into the first feed pipe from the upstream side of the first feed pipe and causes the sand to flow in the downstream direction of the first feed pipe; A second feed pipe arranged in the vertical direction and opening downward, the first feed pipe communicating with the side peripheral surface of the second feed pipe, and the sand flowing into the second feed pipe from the side peripheral surface of the second feed pipe falling and flowing while swirling in the second feed pipe, the second feed pipe; A sorting pipe connected to the second feed pipe in the vertical direction, having a filter for sorting the sand flowing in from the second feed pipe according to its particle size, and the sorting pipe for discharging the sand passing through the filter, a sand drying and sorting device characterized by comprising the same.

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