Cleaning equipment

Abstract

To provide a cleaning device which achieves a high cleaning effect while inhibiting sand from flowing out.SOLUTION: A cleaning device includes: a container 3 having an inflow port 341 through which liquid flows and a discharge port 331 from which a part of the liquid is discharged, the container 3 configured to generate swirl flow in the liquid flowing thereinto; and a storage tank 4 which stores stored liquid containing impurities and sand in a state that the stored liquid faces the discharge port 331. The discharge port 331 suctions the impurities and liquid components in the storage tank 4 while discharging a part of the liquid to the storage tank 4. The container 3 has, between the inflow port 341 and the discharge port 331, a contraction part in which a cross sectional area of an internal space X1 defined by an inner peripheral surface of the container 3 is reduced more at the discharge port 331 side than at the inflow port 341 side. Further, the container 3 is connected with a delivery port 611 which sends out the impurities and the liquid components suctioned from the discharge port 331 to the outside of the container 3. The discharge port 331 has an opening area which is larger than or equal to an opening area of the inflow port 341.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a cleaning device for cleaning sand. [Background technology]

[0002] Sewage treatment facilities are equipped with settling basins for removing sand from wastewater. In the settling basin, sand contained in the received wastewater is collected in a sand collection pit at the bottom of the basin, and the collected sand is then transported together with the wastewater using a sand lifting pump. The sand and wastewater transported by the sand lifting pump contain contaminants such as sediment and organic matter. Most of these contaminants have a lower specific gravity than sand. The transported sand is then buried in a landfill or other disposal site. However, if the sand contains a large amount of contaminants, it may generate methane gas and other contaminants, which may prevent the landfill from accepting the sand. For this reason, a cleaning device has been developed that uses a sand washing cyclone to clean the wastewater containing the contaminants and sand transported by the sand lifting pump (see, for example, Patent Document 1). The cleaning device in Patent Document 1 has a weir and an annular trough above the sand washing cyclone. In this cleaning device, the sand and impurities mixed in the wastewater that flow into the sand washing cyclone are drawn into the upward flow generated within the sand washing cyclone along with the wastewater, sent to the top of the sand washing cyclone, and then sent out of the cleaning device through an annular gutter. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2013-59755 Summary of the Invention [Problem to be solved by the invention]

[0004] However, the washing device disclosed in Patent Document 1 is configured so that wastewater containing sand and impurities transported from a sand lifting pump flows into a sand washing cyclone, where the sand settles at the bottom of the cyclone and is then dumped onto a recovery conveyor connected to the discharge outlet at the bottom of the cyclone. As a result, sand before being dumped onto the recovery conveyor accumulates at the bottom of the sand washing cyclone and is easily drawn into the upward flow within the cyclone and sent to the top of the cyclone, potentially causing a considerable amount of sand to overflow the weir and flow out of the washing device. While attempts to address this issue by weakening the upward flow to the extent that sand is not dumped outside the washing device result in the impurities being more difficult to draw into the upward flow, resulting in a reduced washing effect.

[0005] In view of the above circumstances, an object of the present invention is to provide a cleaning device that has a high cleaning effect while suppressing the outflow of sand. [Means for solving the problem]

[0006] The cleaning device of the present invention, which solves the above-mentioned object, comprises: a container having an inlet through which a liquid flows and an outlet through which a swirl flow is generated in the flowing liquid and a part of the liquid is discharged; a storage tank facing the discharge port for storing the stored liquid containing the impurities and sand, the outlet is configured to discharge a portion of the liquid into the storage tank while sucking the impurities and liquid components in the storage tank through the outlet; the container has a constricted portion between the inlet and the outlet, in which the cross-sectional area of ​​an internal space defined by an inner peripheral surface of the container is smaller on the outlet side than on the inlet side, and is connected to a delivery port that delivers the impurities and the liquid component sucked in from the delivery port to the outside of the container; the storage tank is one in which the interior thereof is in communication with the atmosphere, The outlet has an opening area equal to or larger than the opening area of ​​the inlet. and the released gas in the reservoir tank It is characterized by being something.

[0007] In this cleaning device, the outlet may have an opening area equal to or larger than the opening area of ​​the inlet.

[0008] In this cleaning device, the delivery port may have an opening area equal to or larger than the opening area of ​​the discharge port.

[0009] The cleaning device further comprises a delivery pipe that receives the impurities and the liquid component from one end where the delivery port is formed and discharges the impurities and the liquid component from the other end that is located below the one end, When the delivery tube is filled with the liquid component, it may generate a force that draws up the impurities and the liquid component from the delivery port and causes them to flow out from the other end by the principle of a siphon. [Effects of the Invention]

[0010] According to the present invention, it is possible to provide a cleaning device that has a high cleaning effect while suppressing the outflow of sand. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a schematic diagram showing a settling basin in which a cleaning device corresponding to one embodiment of the present invention is disposed. [Figure 2] 2(a) is a plan view of the container shown in FIG. 1, and FIG. 2(b) is a cross-sectional view taken along the line AA in FIG. 2(a). [Figure 3] 2 is a front view showing the container, the storage tank, and the lower part of the carrying-out device shown in FIG. 1. FIG. [Figure 4] 2 is a right side view showing the container, the storage tank, and the lower part of the carrying-out device shown in FIG. 1. FIG. [Figure 5] 2 is a flowchart showing the operation of the cleaning device shown in FIG. [Figure 6] 1. FIG. 4 is a front view similar to FIG. 3, showing a modification of the cleaning device shown in FIG. [Figure 7] 1. FIG. 4 is a schematic diagram similar to FIG. 1, showing a second embodiment of the cleaning device shown in FIG. [Figure 8] 8 is a flowchart showing the operation of the cleaning device shown in FIG. DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the description of this embodiment, an example in which the present invention is applied to a washing device that removes impurities from wastewater and sand transferred from a grit basin is used. The grit basin is located upstream of a sewage treatment facility and is used to remove sand from wastewater such as sewage or rainwater. The wastewater from which sand has been removed in the grit basin is sent to a sedimentation basin or other downstream facility. The impurities are separated from the wastewater by an impurity removal screen or other device and treated.

[0013] FIG. 1 is a schematic diagram showing a grit basin in which a cleaning device corresponding to one embodiment of the present invention is disposed.

[0014] As shown in FIG. 1, the settling basin 9 in which the washing device 1 of this embodiment is installed is a basin equipped with a pump well 91, a trough 92, a sand collection nozzle 93, and a sand collection pit 94. Wastewater flows into the settling basin 9 from the right side of the figure. The flowing wastewater flows slowly toward the left side of the figure. As the wastewater flows through the settling basin 9, the sand contained in the wastewater settles toward the bottom of the basin. The pump well 91 is located at the most downstream side of the settling basin 9. The pump well 91 is a portion where the wastewater from which sand has been removed is stored. A lifting pump 911 is installed inside the pump well 91. The lifting pump 911 sends the wastewater stored in the pump well 91 to the outside of the settling basin 9. A lifting pipe 912 is connected to the lifting pump 911. The wastewater sucked by the lifting pump 911 is sent through the lifting pipe 912 to a settling basin (not shown). The sewage pond water level WL1 is also shown in Figure 1. The position of this pond water level WL1 varies in height from the bottom of the trough 92 within a range of, for example, 1 m to 5 m depending on the amount of sewage flowing into the settling basin 9.

[0015] The trough 92 is formed in the center of the pond width direction at the bottom of the pond upstream of the pump well 91. This trough 92 extends along the direction in which the wastewater flows in the settling basin 9. On both sides of the trough 92 in the pond width direction, a pond bottom slope 95 is formed on the bottom of the pond that slopes downward toward the trough 92. The sand contained in the wastewater that flows into the settling basin 9 settles toward the bottom of the pond and slides down the pond bottom slope 95 or is deposited directly in the trough 92.

[0016] The sand collection nozzle 93 is disposed at the upstream end of the trough 92. The sand collection nozzle 93 is supplied with wastewater pumped up from the above-mentioned sedimentation basin (not shown). The wastewater supplied to the sand collection nozzle 93 is discharged from the tip of the sand collection nozzle 93 toward the downstream side of the sedimentation basin 9. The downstream end of the trough 92 is connected to a sand collection pit 94. Sand deposited in the trough 92 is collected in the sand collection pit 94 by the flow of water discharged from the sand collection nozzle 93.

[0017] The sand collection pit 94 is formed between the pump well 91 and the trough 92. The sand collected in the sand collection pit 94 is sent to the washing device 1 by a sand lifting pump 941. The sand lifting pump 941 is located inside the sand collection pit 94 near the bottom of the sand collection pit 94. A sand lifting pipe 942 is connected to the sand lifting pump 941. The sand lifting pump 941 sucks the sand collected inside the sand collection pit 94 together with the wastewater, and transfers the wastewater mixed with sand to the container 3 through the sand lifting pipe 942. The sand and wastewater transferred by the sand lifting pump 941 contain impurities such as screen residue and organic matter. Most of these impurities have a lower specific gravity than sand. Hereinafter, the wastewater mixed with impurities and sand transferred to the container 3 by the sand lifting pump 941 will be referred to as mixed water. This mixed water corresponds to an example of a liquid. The percentage of sand contained in the mixed water transferred to container 3 by sand lifting pump 941 varies depending on factors such as the amount of sand collected inside sand collection pit 94, but is approximately 5% on average. The mixed water transferred to container 3 by sand lifting pump 941 is approximately 2.0 m3 / min. The amount of mixed water flowing into container 3 is determined by the capacity of sand lifting pump 941. For this reason, the sand lifting pump 941 is appropriately selected depending on the size of container 3 and storage tank 4. However, in order to balance the amount of impurities and liquid components pumped from storage tank 4 (described below) with the concentrated water (described below) discharged from outlet 331 of container 3, it is preferable to use a sand lifting pump 941 that allows mixed water to flow into container 3 at a rate of 2.0 m3 / min or more. On the other hand, using a sand-lifting pump 941 with an unnecessarily high capacity will only increase the price and power consumption of the sand-lifting pump 941, so it is preferable to use a sand-lifting pump 941 that allows the amount of mixed water flowing into the container 3 to be 4 m3 / min or less.

[0018] The washing apparatus 1 includes a container 3, a storage tank 4, a discharge device 5, and a delivery pipe 6. The container 3, the storage tank 4, and the delivery device 5 are disposed on the ground near a settling basin 9. The washing apparatus 1 of this embodiment also corresponds to an example of a sand separation apparatus that separates sand from entrained water. The lower portion of the container 3 is disposed within the storage tank 4, and the upper portion of the container 3 protrudes above the storage tank 4. The container 3 is a so-called liquid cyclone that removes a certain amount of wastewater and impurities from the entrained water that has flowed in and delivers the water to the delivery pipe 6. The container 3 also discharges concentrated water, which has a higher concentration of sand due to the removal of a certain amount of wastewater and impurities, into the storage tank 4. This discharged concentrated water corresponds to part of the liquid. The wastewater and impurities delivered directly from the container 3 to the delivery pipe 6 are returned to the settling basin 9 through the delivery pipe 6 together with impurities and liquid components pumped up from the storage tank 4 (described later). Hereinafter, the wastewater and impurities delivered directly from the container 3 to the delivery pipe 6 and the impurities and liquid components pumped up from the storage tank 4 and delivered to the delivery pipe 6 will be collectively referred to as delivery water. Hereinafter, the sand, impurities, and liquid components stored in the storage tank will be collectively referred to as stored liquid. The delivery pipe 6 has one end 61 connected to the container lid 312 of the container 3, a horizontal portion extending horizontally above the container 3, and a vertical portion bending from the horizontal portion and extending downward. The other end 6a, which is the lower end of the vertical portion, is located below the container 3 and outside the storage tank 4, upstream of the settling basin 9. By arranging the other end 6a upstream of the sand collection pit 94 of the settling basin 9, even if sand is accidentally discharged from the cleaning device 1 through the delivery pipe 6, the sand will settle to the bottom of the settling basin 9 as it flows downstream, and can be transferred back to the container 3. The other end 6a of the delivery pipe 6 may be extended below the water level WL1 of the settling basin 9 so that the other end 6a is submerged in water. Furthermore, the other end 6a may be arranged near the bottom of the settling basin 9. The container 3 and the storage tank 4 will be described in detail later.

[0019] The unloading device 5 is connected to the lower end of the storage tank 4 and extends diagonally upward. The unloading device 5 has a screw conveyor 51 and a drop port 52. The screw conveyor 51 is disposed within the unloading device 5. The axial direction of the screw conveyor 51 coincides with the extension direction of the unloading device 5. A motor 53 and a drive transmission mechanism 54 are fixed to the upper end portion of the unloading device 5. When the motor 53 is driven, the screw conveyor 51 rotates via the drive transmission mechanism 54. The drive transmission mechanism 54 is composed of sprockets fixed to the drive shaft of the motor 53 and the screw conveyor 51, and chains wound around each sprocket, but may also be composed of other mechanical transmission elements such as gears. Alternatively, the motor 53 and the screw conveyor 51 may be directly connected without providing the drive transmission mechanism 54. The sand contained in the concentrated water discharged into the storage tank 4 settles within the storage tank 4 and flows into the discharge device 5 connected to the storage tank 4, where it is drained and transported diagonally upward as the screw conveyor 51 rotates. The drop port 52 is located near the upper end of the screw conveyor 51. The sand drained by the screw conveyor 51 is dropped downward from the drop port 52. In other words, the discharge device 5 discharges the sand contained in the liquid stored in the storage tank 4 to the outside of the storage tank 4. Note that the screw conveyor 51 may be replaced with another transport mechanism such as a belt conveyor.

[0020] Fig. 2(a) is a plan view of the vessel shown in Fig. 1, and Fig. 2(b) is a cross-sectional view taken along line AA in Fig. 2(a). Fig. 2(a) and Fig. 2(b) also show one end portion 61 of the delivery pipe 6 and a part of the sand lifting pipe 942.

[0021] As shown in FIG. 2(b), the container 3 includes a fluid introduction section 31, a throttle section 32, a discharge section 33, and a fluid inlet pipe 34. The fluid introduction section 31 is provided in the upper portion of the container 3. The upper end of the throttle section 32 is connected to the lower end of the fluid introduction section 31. The upper end of the discharge section 33 is connected to the lower end of the throttle section 32. The inner circumferential surface 3a of the container 3 is formed by the inner circumferential surface 31a of the fluid introduction section 31, the inner circumferential surface 32a of the throttle section 32, and the inner circumferential surface 33a of the discharge section 33. The inner circumferential surface 3a of the container 3 defines an internal space X1. In other words, the fluid introduction section 31, the throttle section 32, and the discharge section 33 form a hollow tank having the internal space X1.

[0022] The fluid introduction section 31 includes a cylindrical section 311 having a cylindrical inner circumferential surface 31a, and a container lid 312 that closes the upper end of the cylindrical section 311. The cylindrical section 311 is made of a 3.2 mm thick steel plate processed into a cylindrical shape with an inner diameter of 500 mm. The container lid 312 is made of a 6.0 mm thick steel plate processed into a ring shape with an outer diameter of 586 mm and an inner diameter of 216 mm. The container lid 312 is provided with an inspection door (not shown), which allows air to flow into and out of the container 3. The shape, material, and thickness of the cylindrical section 311 and the container lid 312 may be selected appropriately depending on the size of the internal space X1, etc.

[0023] The fluid inlet pipe 34 is connected to the upper portion of the cylindrical portion 311. The sand lifting pump 941 and the fluid inlet pipe 34 shown in FIG. 1 are connected via a sand lifting pipe 942. The sand lifting pipe 942 and the fluid inlet pipe 34 are detachably coupled by fastening flanges at their connecting ends together with bolts. The fluid inlet pipe 34 is a pipe with an inner diameter of 100 mm. As shown in FIG. 2(b), an inlet 341 is formed at the connection between the fluid inlet pipe 34 and the cylindrical portion 311. As indicated by the straight arrow pointing right in FIGS. 2(a) and 2(b), the mixed water pumped up by the sand lifting pump 941 is introduced into the internal space X1 through the inlet 341 in the tangential direction of the inner circumferential surface 31a of the cylindrical portion 311. This creates a swirling flow of mixed water in the internal space X1.

[0024] The throttle section 32 is disposed between the inlet 341 and the outlet 33. In this throttle section 32, the cross-sectional area of ​​the internal space X1 decreases toward the outlet 33. In other words, the throttle section 32 has an inverted conical inner surface 32a whose diameter gradually decreases with increasing distance from the cylindrical section 311. This throttle section 32 is formed by processing a steel plate with a thickness of 3.2 mm into a conical shape, with an inner diameter of 500 mm at the upper end and 100 mm at the lower end. The material and thickness of the throttle section 32 may be selected appropriately depending on the size of the internal space X1, the amount of narrowing, and the like. The throttle section 32 may also be formed so that the cross-sectional area of ​​the internal space X1 gradually decreases with increasing distance from the cylindrical section 311. That is, the throttle section 32 may be formed so that the cross-sectional area of ​​the internal space X1 is smaller on the outlet 331 side than on the inlet 341 side. The cross-sectional area of ​​the lower end of the throttle section 32 is equal to the opening area of ​​the outlet 331. In this embodiment, the cross-sectional area of ​​the lower end of the throttle section 32, i.e., the opening area (cross-sectional area) of the outlet 331, is set to be equal to the opening area (cross-sectional area) of the inlet 341. However, the opening area of ​​the outlet 331 may be equal to or greater than the opening area of ​​the inlet 341. However, if the opening area of ​​the outlet 331 is made too small, the pressure loss in the container 3 increases, so the opening area of ​​the outlet 331 is preferably equal to or greater than the opening area of ​​the inlet 341. In addition, if the opening area of ​​the outlet 331 is made too small or too large, the suction action from the storage tank 4 to the container 3, which will be described later, decreases, so it is desirable to set the opening area of ​​the outlet 331 to be 50% or more and 150% or less of the opening area of ​​the inlet 341. A container flange 321 protruding toward the outside of the container 3 is formed at the upper end of the throttle section 32.

[0025] The discharge section 33 is connected to the side of the throttle section 32 opposite to the side to which the fluid introduction section 31 is connected. In other words, the discharge section 33 is connected to the lower end of the throttle section 32. The discharge section 33 is cylindrical with a flange 332 formed at the lower end. The opening at the lower end of this discharge section 33 becomes the discharge port 331. Note that the discharge section 33 may be omitted. In that case, the opening at the lower end of the throttle section 32 becomes the discharge port. The flange 332 is annular with an outer diameter of 200 mm.

[0026] The delivery pipe 6 has an inner diameter of 200 mm. One end portion 61 of the delivery pipe 6 is watertightly connected to the container lid 312 by welding. Alternatively, the one end portion 61 may protrude into the internal space X1. The lower end of the one end portion 61 forms one end of the delivery pipe 6, and the opening of that end forms the delivery outlet 611. Therefore, the one end portion 61 and the delivery outlet 611 are connected to the container 3. The delivery water delivered from the delivery outlet 611 is returned to the settling basin 9 through the delivery pipe 6. In Figures 2(a) and 2(b), the flow direction of the delivery water is indicated by a straight arrow pointing left. The opening area of ​​the delivery outlet 611 is preferably equal to or larger than the opening area of ​​the discharge outlet 331. This increases the amount of delivery water discharged from the delivery outlet 611 and reduces pressure loss in the container 3. The opening area of ​​the delivery outlet 611 is preferably equal to or larger than the opening area of ​​the inlet 341. This allows a larger amount of fluid to be delivered from the delivery port 611 than the amount of mixed water flowing in from the inlet 341. In this embodiment, the opening area of ​​the delivery port 611 is four times the opening area of ​​the outlet 331 and the inlet 341.

[0027] Fig. 3 is a front view showing the container, the storage tank, and the lower part of the carrying-out device shown in Fig. 1. Fig. 4 is a right side view showing the container, the storage tank, and the lower part of the carrying-out device shown in Fig. 1.

[0028] As shown in FIG. 3 , the storage tank 4 includes a sidewall 41 positioned outside the container 3 and extending above the discharge port 331, a tank lid 42 closing the upper end of the sidewall 41, and legs 43 supporting the storage tank. In this embodiment, the sidewall 41 extends from below the discharge port 331 to the height of the connection between the throttled section 32 and the fluid introduction section 31. A hole having the same diameter as the outer periphery of the fluid introduction section 31 of the container 3 is formed in the center of the tank lid 42 in a plan view. The container 3 is joined to the storage tank 4 by welding the container flange 321 to the tank lid 42 with the upper end portion of the throttled section 32 inserted into the hole. A deodorizing pipe 421 is provided on the tank lid 42. The legs 43 are located at each of the four corners of the storage tank 4 in a plan view. In FIG. 3 , only the upper and lower ends of the legs 43 are shown, with the middle portion omitted. The lower ends of the legs 43 are grounded, allowing the storage tank 4 to be placed above ground. It should be noted that a support member for supporting the carry-out device 5 is also provided at the middle portion of the carry-out device 5 in the extending direction, but this support member is not shown.

[0029] The upper portion of the storage tank 4 is formed as a rectangular tube with a substantially square shape in a plan view. As shown in FIG. 4, a tank inclined surface 41a is formed on the lower portion of the storage tank 4. The lower end of this tank inclined surface 41a is connected to the discharge device 5. Also, as shown in FIG. 3, the lower end of the storage tank 4 is notched obliquely upward at the same angle as the inclination angle of the discharge device 5. Sand contained in the concentrated water discharged from the discharge port 331 of the container 3 slides down the tank inclined surface 41a or is deposited in the lower portion of the discharge device 5, which is directly connected to the lower end of the storage tank 4. As described above, the sand deposited in the discharge device 5 is discharged to the outside of the cleaning apparatus 1 by the screw conveyor 51. A discharge pipe 55 is provided at the lower end of the discharge device 5 for discharging liquid and sand remaining in the storage tank 4 and the discharge device 5 during inspection, etc. A valve (not shown) is provided on this discharge pipe 55. 3 and 4 also show the tank water surface WL2 formed at a height facing the discharge port 331 by the supernatant liquid of the stored liquid discharged from the discharge port 331.

[0030] Next, we will explain the driving method and operation of this cleaning device 1. Figure 5 is a flowchart showing the operation of the cleaning device shown in Figure 1.

[0031] The operations of the settling basin 9 and the cleaning device 1 are centrally controlled by a control device (not shown). The settling basin 9 and the cleaning device 1 may each be provided with a control device, allowing them to transmit and receive information or commands to and from each other. When a certain amount of sand accumulates on the bottom of the settling basin 9 shown in FIG. 1 at a predetermined time, the settling basin 9 discharges wastewater from a sand collection nozzle 93 to collect the sand accumulated in the trough 92 in a sand collection pit 94. After the sand collection operation, the cleaning device 1 begins a cleaning operation. The predetermined time may be periodically, for example, once a month, or when the total flow rate of wastewater flowing into the settling basin 9 or the total flow rate of wastewater discharged from the settling basin 9 reaches a certain amount. The cleaning operation may also be initiated while sand is being collected in the sand collection pit 94. The cleaning device 1 of this embodiment also functions as a sand separator, so sand is also removed during the cleaning operation.

[0032] In the cleaning operation, the sand pump 941 is first started. This starts the inflow of contaminated water into the container 3 (step S11). The contaminated water flows in from the tangential direction of the inner circumferential surface 31a of the cylindrical portion 311, forming a swirling flow of contaminated water near the inner circumferential surface 3a of the container 3 in the internal space X1. The sand contained in the contaminated water has a greater specific gravity than the contaminants and wastewater. Therefore, the sand is pressed against the inner circumferential surface 3a of the container 3 by centrifugal force, and gradually falls downward while swirling along the inner circumferential surface 3a. Meanwhile, the contaminants and wastewater, which have had the sand removed from the contaminated water, gather in the radial center of the container 3, generating an upward flow. This upward flow causes the contaminants and wastewater gathered in the center to be discharged from the discharge outlet 611 at the top of the container 3. The discharged contaminants and wastewater then pass through the discharge pipe 6 and are released into the grit basin 9 from the other end 6a of the discharge pipe 6. The other end 6a of this delivery pipe 6 is positioned below the delivery outlet 611 formed at one end of the delivery pipe 6, so when the delivery pipe 6 is filled with liquid, a force is generated due to the siphon principle that sucks up mixed water and the like in the internal space X1 from the delivery outlet 611 and causes it to flow out into the settling basin 9. This increases the amount of delivery water, further enhancing the suction action at the discharge outlet 331, which will be described later.

[0033] In the internal space X1, the sand gradually falls downward while swirling along the inner circumferential surface 3a, and begins to be discharged as concentrated water from the discharge port 331 together with a certain amount of impurities and wastewater (step S12). The concentrated water is discharged radially from the discharge port 331 due to the centrifugal force of the swirling flow. In Figures 3 and 4, the direction of concentrated water discharge is indicated by curved arrows. If the storage tank 4 is empty when the discharge of concentrated water begins, the water level WL2 in the storage tank 4 gradually rises. Furthermore, the sand contained in the stored liquid in the storage tank 4 settles toward the bottom of the storage tank 4 due to its own weight and accumulates in the lower part of the carry-out device 5. Note that as the amount of accumulated sand increases, the sand that does not fit into the lower part of the carry-out device 5 also accumulates in the lower part of the storage tank 4. Among the impurities contained in the stored liquid, those with a low specific gravity float in the supernatant wastewater of the stored liquid, while those with a high specific gravity slowly settle in the wastewater.

[0034] As the tank water level WL2 rises and reaches a height position facing the outlet 331 (YES in step S13), as shown in FIGS. 3 and 4, the wastewater, which is the supernatant liquid of the stored liquid facing the outlet 331, is sucked into the outlet 331 together with the floating impurities (step S14). This wastewater sucked into the outlet 331 is an example of a liquid component. Hereinafter, the impurities sucked into the outlet 331 and the wastewater will be collectively referred to as the impurity-containing liquid component. The impurity-containing liquid component is sucked from the radial center of the outlet 331 by the upward flow within the container 3. In FIGS. 3 and 4, the direction in which the impurity-containing liquid component is sucked in is indicated by a straight arrow. When this impurity-containing liquid component is sucked into the outlet 331, the air around the outlet 331 is also sucked into the outlet 331. That is, the outlet 331 sucks in a volume of fluid (impurity-containing liquid components and air) greater than the volume of the concentrated water being discharged. In this embodiment, the outlet 611 has an opening area larger than that of the outlet 331, allowing a large volume of fluid to be discharged from the outlet 611. As a result, fluid can be easily sucked in from the outlet 331. Even if a volume of fluid greater than the volume of the concentrated water being discharged is sucked in from the outlet 331, it can still be discharged from the outlet 611. When the impurity-containing liquid components and air are being sucked in from the outlet 331, a balanced state is formed in which the volume of the concentrated water discharged from the outlet 331 to the storage tank 4 and the volume of the impurity-containing liquid components sucked into the internal space X1 from the outlet 331 are approximately equal. The volume of air sucked into the outlet 331 is ⅕ or less of the volume of the impurity-containing liquid components. In this embodiment, a flange 332 that expands in the horizontal direction is formed around the outlet 331, making it difficult for air above the outlet 331 to be sucked into the outlet 331. In addition, the flange 332 suppresses rippling of the tank water surface WL2 near the outlet 331. As a result, air is less likely to be sucked into the outlet 331, and the ratio of impurity-containing liquid components to air that are sucked into the outlet 331 is increased. Furthermore, the flange 332 makes it easier for the concentrated water discharged from the outlet 331 to be discharged in an orderly radial direction.As a result, sand contained in the concentrated water discharged from the outlet 331 is prevented from mixing with the impurity-containing liquid components sucked in from the radial center of the outlet 331. The height position at which the tank water level WL2 faces the outlet 331 refers to the position at which the tank water level WL2 reaches a height at which the distance between the tank water level WL2 and the outlet 331 is 0 mm or more and 20 mm or less. As described above, because the concentrated water is discharged radially from the outlet 331, sand contained in the concentrated water is unlikely to be sucked in from the center of the outlet 331. In addition, sand has a high specific gravity and tends to settle quickly to the bottom of the storage tank 4. Therefore, even if a strong upward flow is formed in the container 3 and the suction force generated at the outlet 331 is strong, the amount of sand sucked into the container 3 is extremely limited. Because this very small amount of sand has a higher specific gravity than the impurity-containing liquid components, most of it is expelled radially from the ascending flow within container 3, absorbed into the swirling flow, and then discharged again from outlet 331 into storage tank 4. As described above, air is also drawn in through outlet 331, so the ascending flow occurring in the center of container 3 is a flow of fluid with a low specific gravity mixed with the drawn-in air. Therefore, the difference in specific gravity between the fluid that mainly constitutes the ascending flow and the sand becomes greater, and the sand with a high specific gravity is more likely to be expelled radially. In addition, the stored liquid in storage tank 4 is agitated by the released concentrated water. This agitation causes impurities contained in the stored liquid that have a higher specific gravity than the liquid components of the stored liquid to easily rise up and float in the stored liquid.

[0035] If the amount of contaminated water flowing into the container 3 is less than 2.0 m3 / min, the amount of impurity-containing liquid components drawn into the outlet 331 will be less than the concentrated water discharged from the outlet 331, and the tank water level WL2 may rise beyond the outlet 331. However, when the tank water level WL2 reaches the outlet 331, the outlet 331 is blocked by the retained liquid, and the amount of concentrated water discharged from the outlet 331 decreases. That is, the resistance caused by the reduced cross-sectional area of ​​the internal space X1 in the throttle section 32, combined with the water pressure of the retained liquid acting on the outlet 331, makes it difficult for the concentrated water to be discharged from the outlet 331. As the tank water level WL2 rises, the water pressure of the retained liquid acting on the outlet 331 increases, and the amount of concentrated water discharged from the outlet 331 decreases, and the amount of water delivered from the delivery port 611 increases. Furthermore, as described above, when the delivery pipe 6 is filled with liquid, the delivery water tends to flow out of the delivery port 611 into the grit basin 9 due to the siphon principle, further increasing the amount of delivery water delivered from the delivery port 611. As a result, the amount of impurity-containing liquid components drawn into the discharge port 331 increases, causing the tank water level WL2 to drop to a position facing the discharge port 331. In other words, while the tank water level WL2 is dropping, an amount of impurity-containing liquid components greater than the amount of concentrated water discharged from the discharge port 331 is being drawn in. In this way, reducing the amount of contaminated water flowing into the container 3 allows the use of an inexpensive sand pump 941, thereby reducing the amount of electricity used by the sand pump 941. Note that even when the tank water level WL2 is above the discharge port 331, the stored liquid remains facing the discharge port 331.

[0036] When a first predetermined time has elapsed since the start of operation of the sand raising pump 941 (YES in step S15), the operation of the sand raising pump 941 is stopped (step S16). This first predetermined time is the time required for the sand raising pump 941 to suck up most of the sand collected in the sand collection pit 94, and is set appropriately depending on the capacity of the sand raising pump 941 and the amount of sand that can be collected in the sand collection pit 94. Stopping the sand raising pump 941 also stops the inflow of mixed water into the container 3, the discharge of concentrated water into the storage tank 4, the suction of impurity-containing liquid components, and the delivery of delivery water. Steps S11 to S16 described above correspond to an example of an inflow process. Steps S14 to S16 correspond to an example of a discharge / suction process.

[0037] Once the sand lifting pump 941 has stopped operating, the carry-out device 5 is started (step S17). By operating the carry-out device 5, the sand accumulated in the lower portion of the carry-out device 5 is transported diagonally upward along the carry-out path of the carry-out device 5. When the carry-out device 5 starts operating, the tank water level WL2 is approximately aligned with the discharge port 331, and the carry-out path extends to a higher position. Therefore, the sand transported by the screw conveyor 51 is drained while being transported in the latter half of the carry-out path, which is higher than the tank water level WL2. Then, the sand that reaches the upper end of the carry-out path of the carry-out device 5 is dropped downward from the drop port 52. When a second predetermined time has elapsed since the start of operation of the carry-out device 5 (YES in step S18), the carry-out device 5 stops operating (step S19). Steps S17 to S19 described above correspond to an example of a carry-out process. This second predetermined time is the time required for most of the sand collected in the lower portion of the carry-out device 5 to be transported and dropped from the drop port 52. Instead of determining whether the second predetermined time has elapsed, a sand presence / absence sensor that detects the presence or absence of sand in the lower portion of the carry-out device 5 may be provided in the carry-out device 5, and the determination may be made based on whether this detection has occurred. This completes the operation of the cleaning device. While the carry-out device 5 is operating, the tank water level WL2 is positioned approximately in line with the discharge port 331, so even if the carry-out path is short, the sand can be transported while draining. Because the carry-out path extends diagonally upward, shortening the carry-out path reduces the width and height of the carry-out device 5. As a result, the cleaning device 1 can be made more compact. The carry-out device 5 may be started before the sand lifting pump 941 is stopped, or before the sand lifting pump 941 is started. However, by starting the drive of the discharge device 5 after the drive of the sand lifting pump 941 has been stopped, cleaning can be performed for a long time, and therefore the cleaning effect of the cleaning device 1 can be improved.

[0038] Next, a modified example of this embodiment will be described. In the following description, the names of components that are the same as those described above may be assigned the same reference numerals as those used above, and duplicate descriptions may be omitted.

[0039] FIG. 6 is a front view similar to FIG. 3, showing a modification of the cleaning device shown in FIG.

[0040] As shown in FIG. 6, the cleaning apparatus 1 of this modification differs from the cleaning apparatus 1 shown in FIG. 1 in that a cleaning water supply pipe 45 is connected to the storage tank 4. The cleaning water supply pipe 45 penetrates the side wall 41 of the storage tank 4 in a watertight manner. An outlet 451 is formed at the tip of the cleaning water supply pipe 45. The outlet 451 is located inside the storage tank 4, at the lower end portion of the storage tank 4. A valve 452 is provided on the cleaning water supply pipe 45. When the valve 452 is opened, purified water is discharged from the outlet 451. As a result, purified water is injected into the storage tank 4 at a rate of approximately 0.2 m3 / min. This purified water corresponds to an example of cleaning water. In this modification, the discharge water is discharged from the delivery port 611 at a rate of approximately 2.2 m3 / min. Although the valve 452 is a manual valve in this modification, it may also be an electrically operated valve. The outlet 451 discharges purified water toward sand accumulated at the lower end portion of the storage tank 4. This configuration can stir up the accumulated sand and lift up impurities buried in the sand. It is preferable to adjust the pressure at which the purified water is discharged so that the sand does not rise to the vicinity of the tank water level WL2. Although this reduces the cleaning effect, the discharge port 451 may be provided at the top of the storage tank 4, and purified water may be injected from above the tank water level WL2.

[0041] The injection of purified water into the storage tank 4 is performed between step S11 (starting the operation of the sand lifting pump 941) and step S16 (stopping the operation of the sand lifting pump 941) shown in FIG. 5, i.e., during the inflow process. However, injection may be started before step S11 so that the tank water level WL2 faces the discharge outlet 331 in advance. In this case, the suction of the impurity-containing liquid component is started simultaneously with the discharge of the concentrated water. From step S14 onward, the height position of the tank water level WL2 and the height position of the discharge outlet 331 become approximately the same. Therefore, almost no air is sucked through the discharge outlet 331. The injection of purified water into the storage tank 4 may be performed after step S11, for example, between step S14 (starting the suction of the impurity-containing liquid component) and step S16 (stopping the operation of the sand lifting pump 941), i.e., during the discharge / suction process. This process of injecting purified water into the storage tank 4 corresponds to an example of an injection process. Injecting purified water can improve the cleaning effect of the cleaning device 1.

[0042] Alternatively, a fine bubble water generator (not shown) may be provided to inject fine bubble water into the reservoir 4 instead of purified water. Fine bubble water is a liquid containing fine bubbles of 100 μm or less. Fine bubble water may be a liquid containing microbubbles, which are bubbles with a diameter of more than 1 μm and 100 μm or less, or may be a liquid containing ultrafine bubbles, which are bubbles with a diameter of 1 μm or less. Furthermore, fine bubble water may be a liquid containing both microbubbles and ultrafine bubbles. The use of fine bubble water can further enhance the cleaning effect of the cleaning device 1.

[0043] Next, a second embodiment will be described. Fig. 7 is a schematic diagram similar to Fig. 1, showing a second embodiment of the cleaning device shown in Fig. 1.

[0044] As shown in FIG. 7 , the settling basin 9 of the second embodiment differs from the washing apparatus 1 and the settling basin 9 shown in FIG. 1 in that the trough 92, sand collection nozzle 93, sand collection pit 94, basin bottom slope 95, sand lifting pump 941, and sand lifting pipe 942 are not present, but a grab bucket type sand lifting device 96 is provided instead, and purified water is introduced into the container 3. The settling basin 9 is equipped with the grab bucket type sand lifting device 96. The grab bucket type sand lifting device 96 includes a rail 961, a mobile winch 962, and a grab bucket 963. The rail 961 is supported by a support 9611 erected above ground in the settling basin 9. The rail 961 is suspended over the entire longitudinal length of the settling basin 9. The mobile winch 962 is configured to be movable along the rail 961. The grab bucket 963 is suspended from the mobile winch 962. The grab bucket 963 grabs the impurities and sand deposited at the bottom of the settling basin 9 and lifts it to the ground using a mobile winch 962. The sand lifted to the ground is dumped into the storage tank 4, whose tank lid 42 is open. A purified water pipe 97 that supplies purified water is connected to the fluid inlet pipe 34 of the container 3.

[0045] FIG. 8 is a flowchart showing the operation of the cleaning apparatus shown in FIG.

[0046] At a predetermined time when a certain amount of sand has accumulated on the bottom of the settling basin 9 shown in FIG. 7 , the grab bucket-type sand lifting device 96 is operated to dump the sand, which has accumulated on the bottom of the settling basin and is mixed with impurities, into the storage tank 4. After the dumping, the tank lid 42 is closed, and the cleaning device 1 starts the cleaning operation. In the cleaning operation, first, the supply of purified water to the container 3 is started. The purified water is supplied by pumping water treated in a sewage treatment facility through the purified water pipe 97. Note that, instead of purified water, untreated wastewater may be supplied from a settling basin or the like. In this modification, the purified water or the like supplied to the container 3 corresponds to an example of a liquid. When the supply of purified water to the container 3 is started, the purified water starts to flow into the container 3 (step S21). The purified water flows in from the tangential direction of the inner circumferential surface 31 a of the cylindrical portion 311, and a swirling flow of purified water is formed near the inner circumferential surface 3 a of the container 3 in the internal space X1. The purified water that flows in due to this swirling flow moves gradually downward while swirling along the inner peripheral surface 3a. Meanwhile, an upward flow is generated in the radial center of the container 3. Due to this upward flow, a certain amount of the purified water that flows in is discharged directly from the discharge outlet 611 at the upper end of the container 3. As shown in Figure 7, the discharged purified water passes through the discharge pipe 6 and is released from the other end 6a of the discharge pipe 6 toward the settling basin 9.

[0047] In the internal space X1, a portion of the purified water gradually moves downward while swirling along the inner circumferential surface 3a, reaches the outlet 331, and begins to be discharged from the outlet 331 (step S22). This discharged portion of the purified water corresponds to a portion of the liquid. A portion of the purified water is discharged radially from the outlet 331 by the centrifugal force of the swirling flow. Because sand containing impurities has accumulated inside the storage tank 4, a portion of the discharged purified water falls onto the sand, forming a tank water level WL2 in the storage tank 4. As a portion of the purified water is discharged, the tank water level WL2 gradually rises. In this second embodiment, the sand containing impurities that was originally added to the storage tank 4 and a portion of the purified water discharged into the storage tank 4 become the stored liquid. When the tank water level WL2 rises and reaches a height position facing the discharge outlet 331 (YES in step S23), the supernatant liquid of the stored liquid facing the discharge outlet 331 is sucked in from the center of the discharge outlet 331 (step S24). Furthermore, the stored liquid stored in the storage tank 4 is stirred by the released purified water, so that the accumulated impurities rise up and are sucked into the discharge outlet 331 together with the supernatant liquid of the stored liquid. This supernatant liquid sucked into the discharge outlet 331 corresponds to an example of a liquid component. Furthermore, the impurities and the supernatant liquid sucked into the discharge outlet 331 become the impurity-containing liquid component. When the impurity-containing liquid component is sucked into the discharge outlet 331, the air around the discharge outlet 331 is also sucked into the discharge outlet 331. That is, an amount of fluid (impurity-containing liquid components plus air) equal to or greater than a portion of the purified water being discharged is sucked in from the outlet 331. When the impurity-containing liquid components and air are being sucked in from the outlet 331, a balanced state is formed in which the amount of purified water discharged from the outlet 331 into the storage tank 4 and the amount of impurity-containing liquid components sucked into the internal space X1 from the outlet 331 are approximately equal. Here, sand contained in the stored liquid is stirred to some extent, but because its specific gravity is greater than that of purified water, it rarely rises to the vicinity of the tank water surface WL2. Therefore, even if the suction force generated at the outlet 331 is strong, only a small amount of sand is sucked into the container 3.Even if it is sucked in, since the sand has a larger specific gravity than the impurity-containing liquid components, most of it is ejected radially from the rising flow in the container 3, swallowed by the swirling flow, and then discharged again from the discharge port 331 into the storage tank 4.

[0048] As in the previous embodiment, when the amount of purified water flowing into the container 3 is less than 2.0 m / min, the tank water level WL2 may rise above the outlet 331. However, once the tank water level WL2 has risen, it will fall to a position facing the outlet 331 due to the water pressure acting on the outlet 331 and the effect of the siphon principle.

[0049] When a first predetermined time has elapsed since the start of the supply of purified water (YES in step S25), the supply of purified water is stopped (step S26). Stopping the supply of purified water also stops the inflow of purified water into the container 3, the discharge of a portion of the purified water into the storage tank 4, the suction of impurity-containing liquid components, and the discharge of the discharge water. Steps S21 to S26 described above correspond to an example of an inflow process. Steps S24 to S26 correspond to an example of a discharge / suction process. The following steps S27 to S29 are the same as steps S17 to S19, so their explanation will be omitted.

[0050] The present invention is not limited to the above-described embodiment, and various modifications can be made within the scope of the claims. For example, in this embodiment, the cleaning device 1 is installed in the settling basin 9, but the cleaning device 1 may be installed somewhere other than the settling basin. Also, although the cleaning device 1 is equipped with the discharge device 5, the discharge device 5 may be omitted. In this case, a sand discharge means such as a belt gate may be provided.

[0051] According to the embodiment and modifications described above, it is possible to obtain a high cleaning effect while suppressing unintended outflow of sand from the cleaning device 1.

[0052] Note that even if a component is included only in the description of the embodiment or each modified example described above, that component may be applied to other embodiments or other modified examples.

[0053] The above-described method of driving the cleaning device generates a swirling flow in the liquid that flows in. a container for discharging a portion of the liquid from a lower outlet; and a container for discharging the stored liquid containing impurities and sand from the discharge port. A method for driving a cleaning device having a storage tank facing the outlet, an inflow step of infusing the liquid into the container; A part of the liquid is discharged from the discharge port into the storage tank while the impurities and and a discharge / suction step of sucking the liquid component through the discharge port and sending it out of the container, The discharge suction step is disposed in the storage tank, and is continuous from the discharge port and extends around the discharge port. A flange that extends horizontally around the enclosure allows air above the outlet to flow into the exhaust. This process is characterized by being carried out in a state where it is difficult for the material to be sucked into the outlet.

[0054] In addition, a swirl flow is generated in the liquid that flows in, and a part of the liquid is discharged from the outlet below. and a storage tank facing the discharge port for storing the liquid containing the impurities and sand. A method for driving a device, comprising: an inflow step of infusing the liquid into the container; A part of the liquid is discharged from the discharge port into the storage tank while the impurities and and a discharge suction step of sucking the liquid component through the discharge port and sending it out of the container. It may be characterized in that:

[0055] Because the sand contained in the stored liquid settles to the bottom of the storage tank, even if a strong upward flow is formed in the container, the amount of sand sucked into the container is limited. Furthermore, the small amount of sand sucked into the container has a higher specific gravity than the impurities and the liquid components, and is therefore easily ejected radially within the container and discharged back into the storage tank. On the other hand, the impurities have a lower specific gravity, and therefore tend to rise up within the storage tank and be sucked in through the outlet, riding on the upward flow within the container. As a result, this method of driving a cleaning device can pump out the impurities in the storage tank while preventing the sand from leaking out of the cleaning device. Hereinafter, the impurities sucked in through the outlet and the liquid components may be collectively referred to as the impurity-containing liquid components.

[0056] Here, the container may be a liquid cyclone. The discharge / suction step may be a step of sucking in, through the outlet, an amount of impurity-containing liquid component equal to or greater than the amount of a portion of the liquid to be discharged into the storage tank. The discharge / suction step may also be a step of sucking in air near the outlet along with the impurity-containing liquid component. The discharge / suction step may also be a step of creating a balanced state in which the amount of the portion of the liquid to be discharged into the storage tank and the amount of the impurity-containing liquid component sucked in through the outlet are approximately equal, and maintaining that state. Additionally, the discharge / suction step may be a step of sucking in, through the outlet, the impurity-containing liquid component near the liquid level of the stored liquid facing the outlet at a height below the outlet, or a step of sucking in the impurity-containing liquid component near the outlet of the stored liquid when the liquid level exceeds the height of the outlet.

[0057] In this method of operating a cleaning device, the discharge and suction process may be a process of sending the impurities and liquid components sucked in from the discharge outlet to the outside of the container through a delivery outlet connected to the container and having an opening area larger than the opening area of ​​the discharge outlet.

[0058] This increases the amount of impurity-containing liquid component that can be delivered from the delivery port, making it easier to suck the impurity-containing liquid component through the discharge port. Furthermore, when the liquid surface of the stored liquid faces the discharge port at a height below the discharge port and there is a gap between the discharge port and the liquid surface, air near the discharge port is sucked through the discharge port along with the impurity-containing liquid component. By increasing the opening area of ​​the delivery port, more of the impurity-containing liquid component mixed with the sucked air can be delivered to the outside of the container. Furthermore, the impurity-containing liquid component mixed with air has a lower specific gravity than the impurity-containing liquid component not mixed with air, resulting in a greater difference in specific gravity between the impurity-containing liquid component and the sand. This makes it easier for the sand, which has a higher specific gravity, to be discharged into the storage tank.

[0059] In the method for driving a cleaning device, the discharge / suction step may be a step of discharging the liquid into the storage tank, thereby stirring the stored liquid in the storage tank.

[0060] By stirring the stored liquid, the impurities contained in the stored liquid that have a specific gravity greater than that of the liquid component also fly up near the discharge port and are more likely to be sucked in through the discharge port.

[0061] Furthermore, in the method for driving this cleaning device, a cleaning liquid for cleaning sand is poured into the storage tank. The method may include an injection step.

[0062] By injecting the cleaning liquid, the cleaning power of the sand contained in the stored liquid can be increased.

[0063] Here, the injection step may be a step of using purified water as the cleaning liquid, or may be a step of using fine bubble water as the cleaning water. The injection step may also be a step of ejecting the cleaning liquid toward the sand accumulated in the lower part of the storage tank. By ejecting the cleaning liquid toward the sand, the sand can be stirred up, causing the impurities buried in the sand to float up. The injection step may be a step performed simultaneously with the inflow step or the discharge / suction step.

[0064] The cleaning device described above has an inlet through which the liquid flows and a nozzle for a vessel having a discharge port for generating a swirling flow in the liquid and discharging a portion of the liquid; a storage tank facing the discharge port for storing the stored liquid containing impurities and sand; A water supply pipe is disposed in the storage tank, and extends continuously from the discharge port in a horizontal direction around the discharge port. and a flange extending from the flange. The container has an interior defined by an inner circumferential surface of the container between the inlet and the outlet. The cross-sectional area of ​​the space has a throttle portion that is smaller on the outlet side than on the inlet side, The outlet discharges a portion of the liquid into the reservoir while removing the impurities and other substances from the reservoir. and the liquid component is sucked through the outlet.

[0065] In addition, the inlet through which the liquid flows in generates a swirling flow in the flowing liquid, and a part of the liquid is a container having an outlet for discharging; a storage tank facing the discharge port for storing the stored liquid containing the impurities and sand, The container has an interior defined by an inner circumferential surface of the container between the inlet and the outlet. The cross-sectional area of ​​the space has a throttle portion that is smaller on the outlet side than on the inlet side, The outlet discharges a portion of the liquid into the reservoir while removing the impurities and other substances from the reservoir. The liquid component may be sucked from the outlet.

[0066] In this cleaning device, even if a strong upward current is formed in the container, the amount of sand sucked into the container is limited. Furthermore, the small amount of sand sucked into the container is likely to be ejected radially within the container and discharged back into the storage tank. Meanwhile, the impurities tend to rise in the storage tank, be sucked through the discharge port, and then rise on the upward current within the container. This allows the impurities in the storage tank to be discharged while preventing the sand from flowing out of the cleaning device.

[0067] Here, the container may be a liquid cyclone. The outlet may suck in an amount of impurity-containing liquid components through the outlet that is equal to or greater than the amount of a portion of the liquid discharged into the storage tank. Furthermore, the outlet may suck in air near the outlet along with the impurity-containing liquid components. The outlet may establish and maintain a balanced state in which the amount of the portion of the liquid discharged into the storage tank and the amount of impurity-containing liquid components sucked in through the outlet are approximately equal. Additionally, the outlet may suck in impurity-containing liquid components near the liquid surface of the stored liquid facing the outlet at a height below the outlet, or may suck in impurity-containing liquid components near the outlet of the stored liquid when the liquid surface exceeds the height of the outlet. The storage tank may be configured to allow air from outside the storage tank to flow into the storage tank.

[0068] In this cleaning device, the container is connected to a delivery port having an opening area larger than an opening area of ​​the discharge port, The delivery port may be configured to deliver the impurities and the liquid component sucked from the discharge port to the outside of the container.

[0069] According to this aspect, the amount of impurity-containing liquid component that can be delivered from the delivery port is increased, making it easier to suck the impurity-containing liquid component through the discharge port. Furthermore, when the liquid surface of the stored liquid faces the discharge port at a height below the discharge port and there is a gap between the discharge port and the liquid surface, air near the discharge port is sucked through the discharge port along with the impurity-containing liquid component. By increasing the opening area of ​​the delivery port, more of the impurity-containing liquid component mixed with the sucked air can be delivered to the outside of the container. Furthermore, the impurity-containing liquid component mixed with air has a lower specific gravity than the impurity-containing liquid component not mixed with air, resulting in a greater difference in specific gravity between the impurity-containing liquid component and the sand. This makes it easier for the sand, which has a higher specific gravity, to be discharged into the storage tank.

[0070] The cleaning device may be provided with a flange extending horizontally around the outlet.

[0071] The flange makes it difficult for air to enter from the sides or above the outlet, so that a large amount of the impurity-containing liquid component can be sucked in through the outlet. The cleaning device described above also includes a container having an inlet through which a liquid flows and an outlet through which a swirling flow is generated in the flowing liquid and a part of the liquid is discharged; a storage tank facing the discharge port for storing the stored liquid containing the impurities and sand, the outlet is configured to discharge a portion of the liquid into the storage tank while sucking the impurities and liquid components in the storage tank through the outlet; the container has a constricted portion between the inlet and the outlet, in which the cross-sectional area of ​​an internal space defined by an inner peripheral surface of the container is smaller on the outlet side than on the inlet side, and is connected to a delivery port that delivers the impurities and the liquid component sucked in from the delivery port to the outside of the container; The outlet has an opening area equal to or larger than the opening area of ​​the inlet. [Explanation of symbols]

[0072] 1 Cleaning equipment 3 containers 4. Reservoir 331 Outlet

Claims

1. a container having an inlet through which a liquid flows and an outlet through which a swirl flow is generated in the flowing liquid and a portion of the liquid is discharged; a storage tank facing the discharge port for storing the stored liquid containing the impurities and sand, the outlet is configured to discharge a portion of the liquid into the storage tank while sucking the impurities and liquid components in the storage tank through the outlet; the container has a constricted portion between the inlet and the outlet, in which the cross-sectional area of ​​an internal space defined by an inner peripheral surface of the container is smaller on the outlet side than on the inlet side, and is connected to a delivery port that delivers the impurities and the liquid component sucked in from the delivery port to the outside of the container; the storage tank is one in which the interior thereof is in communication with the atmosphere, The cleaning device is characterized in that the outlet has an opening area equal to or larger than the opening area of ​​the inlet and is open within the storage tank.

2. 2. The cleaning device according to claim 1, wherein the outlet has an opening area equal to or larger than the opening area of ​​the inlet.

3. 3. The cleaning device according to claim 2, wherein the outlet has an opening area equal to or larger than the opening area of ​​the discharge port.

4. a delivery pipe that receives the impurities and the liquid component from one end where the delivery port is formed and discharges the impurities and the liquid component from the other end that is located below the one end, 4. The cleaning device according to claim 1, wherein when the inside of the delivery tube is filled with the liquid component, the delivery tube generates a force that sucks up the impurities and the liquid component from the delivery outlet and causes them to flow out from the other end using the siphon principle.

Images