Dregs conveying device, and dregs conveying method

Abstract

To provide a dregs conveying device and a dregs conveying method, homogenizing the properties of dregs, preventing troubles, overflow, excessive-torque, and defective solid / liquid separation from occurring in a dregs separator, and improving its solid / liquid separation.SOLUTION: The dregs conveying device comprising a mixing unit mixing dregs and water, a mixed water circulation passage for circulating mixed water prepared in the mixing unit to the mixing unit, a separation unit separating the mixed water into dregs and separated water, a mixed water conveying passage for conveying the mixed water to the separation unit, a crushing unit disposed in the mixing unit to crush the dregs, and a valve for switching the mixed water flow passage from the mixed water circulation passage to the mixed water conveying passage, is characterized in that the mixed water flow passage is switched from the mixed water circulation passage to the mixed water conveying passage upon determining that the properties of the dregs are homogenized in the mixing unit.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a screen residue transporting device and a transporting method, and more particularly to a screen residue transporting device and a transporting method that are provided with a function of crushing screen residue, and that can promote the transport of the screen residue, homogenize the properties of the screen residue, and improve solid-liquid separation. [Background technology]

[0002] In grit basin facilities at sewage treatment plants and pumping stations, screens in wastewater are collected by bar screens and other devices, and then scraped up from the grit basin by rakes or other devices. The scraped up screensid is then dumped into a screensid mixing tank via a crusher. Water is then supplied to the screensid mixing tank, where the crushed screensid and water are mixed. This mixture of crushed screensid and water is then transported through piping by the power of a pump to a screensid separation tank. However, when a large amount of screen residue is generated, foreign matter may become mixed into the screen residue, causing the properties of the screen residue to vary, resulting in malfunction of the screen residue separator, overflow, overtorque, and poor solid-liquid separation. To deal with such a case, it is necessary to constantly supply a large amount of water to the screen residue mixing tank, which is not only uneconomical but also unacceptable when sufficient water cannot be supplied.

[0003] In response to this, for example, Patent Document 1 describes a screen residue cleaning device and its operating method that can deal with hard foreign objects such as stones and cans that are mixed into screen residue, as well as floating foreign objects such as polystyrene foam, and can transport the screen residue through pipes with little energy consumption, thereby improving the cleaning effect of screen residue while saving water. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2017-000989 A Summary of the Invention [Problem to be solved by the invention]

[0005] In the screen residue washing device and its operating method described in Patent Document 1, after the screen residue washing device finishes operating, the drain valve is opened to drain the treated water from the tank, fresh water is fed into the tank to fill it up, and at the next operation, the tank is circulated and washed for a predetermined period of time using the circulation piping, thereby improving the washing effect of the screen residue while saving water. However, this screen residue washing device and its operating method do not directly lead to an improvement in solid-liquid separation in the screen residue separator. Therefore, the inventors discovered that by circulating the screen residue in a mixing tank equipped with a crusher using a screen residue transfer pump, the properties of the screen residue can be homogenized and then the screen residue can be transported to a solid-liquid separator, thereby achieving good solid-liquid separation.

[0006] Therefore, an object of the present invention is to provide a screen residue transport device and method which homogenize the properties of the screen residue, prevent malfunctions, overflow, overtorque, and poor solid-liquid separation in the screen residue separator, and improve solid-liquid separation. [Means for solving the problem]

[0007] As a result of intensive research into the above-mentioned problems, the inventors have discovered that if the screened residue mixed water is circulated in a mixing tank equipped with a crusher, and once it has been determined that the properties of the screened residue have been homogenized, it is possible to homogenize the properties of the screened residue and achieve good solid-liquid separation of the screened residue, and furthermore, because the screened residue separator can be placed on standby while the mixed water is circulating, it is possible to reduce the amount of wash water used in the separator compared to conventional methods, and have completed the present invention. That is, the present invention relates to the following screen residue transport device.

[0008] The screen residue transport device of the present invention for solving the above problems includes a mixing section for mixing screen residue and water, a mixed water circulation path for circulating the mixed water treated in the mixing section to the mixing section, a separation section for separating the mixed water into screen residue and separated water, a mixed water transport path for transporting the mixed water to the separation section, a crushing section for crushing the screen residue installed inside the mixing section, and a valve for switching the flow path of the mixed water from the mixed water circulation path to the mixed water transport path, characterized in that when it is determined in the mixing section that the properties of the screen residue have been homogenized, the flow path of the mixed water is switched from the mixed water circulation path to the mixed water transport path. According to this screen residue transport device, when it is determined that the properties of the screen residue have been homogenized during transport, the mixed water flow path is switched from the mixed water circulation path to the mixed water transport path, and the mixed water is transported to the separation section, thereby improving solid-liquid separation in the screen residue separation section and reducing the amount of wash water used in the separator.

[0009] In addition, one embodiment of the screen residue transport device of the present invention for solving the above-mentioned problems comprises a mixing section for mixing screen residue and water, a mixed water circulation path for circulating the mixed water treated in the mixing section to the mixing section, a separation section for separating the mixed water into screen residue and separated water, a mixed water transport path for transporting the mixed water to the separation section, a crushing section for crushing the screen residue installed inside the mixing section, and a valve for switching the mixed water flow path from the mixed water circulation path to the mixed water transport path, and is characterized in that after the introduction of screen residue begins, the mixed water is circulated through the mixed water circulation path. According to this screen residue transport device, when transporting the screen residue, the mixed water is circulated to the mixing section, and when it is determined that the properties of the screen residue have been homogenized, the flow path of the mixed water is switched from the mixed water circulation path to the mixed water transport path, and the mixed water is transported to the separation section, thereby improving solid-liquid separation in the screen residue separation section and reducing the amount of wash water used in the separator.

[0010] In addition, one embodiment of the screen residue transport device of the present invention is characterized in that it is equipped with a mixed water management section that determines whether the properties of the screen residue have been homogenized in the mixing section and, depending on that determination, switches the flow path of the mixed water from the mixed water circulation path to the mixed water transport path. According to this feature, the homogeneity of the properties of the screen residue in the mixed water can be determined automatically, and the flow path of the mixed water can be automatically switched from the mixed water circulation path to the mixed water transport path, thereby reducing the labor required to operate the screen residue transport device by putting the separator into standby.

[0011] The screen residue transport method of the present invention for solving the above problems includes a mixing step of mixing screen residue and water, a circulation step of circulating the mixed water treated in the mixing section to the mixing step, a separation step of separating the mixed water into screen residue and separated water, a transport step of transporting the mixed water to the separation step, a crushing step installed inside the mixing section for crushing the screen residue, and a valve for switching the flow path of the mixed water from the circulation step to the transport step, and is characterized in that when it is determined in the mixing step that the properties of the screen residue have been homogenized, the flow path of the mixed water is switched from the circulation step to the transport step. According to this screen residue transport method, when it is determined that the properties of the screen residue have been homogenized during transport, the flow path of the mixed water is switched from the mixed water circulation path to the mixed water transport path, and the mixed water is transported to the separation section, thereby improving solid-liquid separation in the screen residue separation section and reducing the amount of wash water used in the separator. Effect of the Invention

[0012] According to the present invention, it is possible to provide a screen residue transport device and method which homogenize the properties of the screen residue, prevent malfunctions, overflow, overtorque, and poor solid-liquid separation in the screen residue separator, and improve solid-liquid separation. [Brief description of the drawings]

[0013] [Figure 1] FIG. 1 is a schematic explanatory diagram showing a screen residue transport device according to a first and second embodiments of the present invention. [Diagram 2] FIG. 11 is a schematic explanatory diagram showing a screen residue transport device according to a third embodiment of the present invention. [Diagram 3] FIG. 13 is an explanatory diagram showing the function of a mixed water management unit in the third embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] The screen residue transport device of the present invention is used to transport screen residue that has been collected in a settling basin facility in a sewage treatment plant, a pumping station, or the like, and has been scooped up from the settling basin by a rake or the like.

[0015] Hereinafter, an embodiment of the screen residue transport device according to the present invention will be described in detail with reference to the drawings. The screen residue transport device described in the embodiment is merely an example for explaining the screen residue transport device according to the present invention, and is not limited thereto. The description of the screen residue transporting method can be replaced with a description of the characteristics and operation of the screen residue transporting device.

[0016] [First embodiment] FIG. 1 is a schematic explanatory diagram showing the structure of a screen residue conveying device 1A in a first embodiment of the present invention. As shown in Fig. 1, the screen residue transporting device 1A according to this embodiment includes a mixing section 2A in which screen residue and water are introduced and mixed with each other, a crushing section 3A installed inside the mixing section 2A and crushing the screen residue, a separation section 4 that separates the mixed water of the crushed screen residue and water (hereinafter simply referred to as "mixed water") into screen residue and separated water, and a separated water circulation path L1 that circulates the separated water discharged from the separation section 4 to the mixing section 2A. Also, as shown in Fig. 1, the screen residue transporting device 1A includes a mixed water transport path L2 that connects the mixing section 2A and the separation section 4 and transports the mixed water, and a pump 5 installed on the mixed water transport path L2. The arrows in Fig. 1 indicate the flow of water.

[0017] The screen residue conveyance device 1A according to this embodiment conveys screen residue in an outline manner. First, screen residue and water are fed into the mixing section 2A, and the screen residue is crushed in the crushing section 3A provided within the mixing section 2A. The resulting mixed water is then discharged from the rear of the crushing section 3A to the outside of the mixing section 2A and transported to the separation section 4 via the mixed water transport line L2 and pump 5. The mixed water is then separated into screen residue and separated water in the separation section 4. The separated water is then supplied to the mixing section 2A via the separated water circulation line L1, whereby the separated water circulates within the screen residue transport device 1A, forming a flow of separated water within the mixing section 2A. Hereinafter, each component of the screen residue transport device 1A in this embodiment will be described.

[0018] [Mixing section] The mixing section 2A is for carrying out a step of mixing the screen residue with water, and may be formed of a channel-type tank in which water is stored up to a predetermined water level. The screened residue that has been scraped up (removed) from the settling basin facility is fed into the mixing section 2A by a screened residue conveyor, and water contained in the screened residue is also fed. In this embodiment, there is no particular limitation on the means for feeding the screen residue and water into the mixing section 2A and the structure related to the feeding. For example, a mixing tank (not shown) for mixing the screen residue and water in advance may be provided upstream of the screen residue transporting device 1A, or a separate point for feeding the screen residue and a separate point for introducing water may be provided in the screen residue transporting device 1A. In addition, the water input into the mixing section 2A is not particularly limited, and examples thereof include tap water, service water, treated water, etc. Considering the cost of procuring water, it is particularly preferable to utilize treated water discharged from a treatment facility such as a sewage treatment plant.

[0019] The screen residue transport device 1A in this embodiment is provided with a separated water input section 21A at one end of the mixing section 2A, into which screen residue and water are input and into which separated water that has been subjected to solid-liquid separation treatment in the separation section 4 described below is input, and a mixed water discharge section 22 at the other end of the mixing section 2A, into which mixed water that has passed through the crushing section 3A is discharged. Inside the mixing section 2A, a separated water flow F1 for transporting the screen residue is formed. As shown in Fig. 1, the direction of the separated water flow F1 in the screen waste transport device 1A of this embodiment is from the separated water inlet 21A toward the crushing section 3A installed inside the mixing section 2A, and the screen waste accumulated at the bottom of the mixing section 2A can be transported to the crushing section 3A by this separated water flow F1. Furthermore, the mixed water that has passed through the crushing section 3A is transported to the mixed water discharge section 22 by the separated water flow F1.

[0020] The means for forming the separated water flow F1 within the mixing section 2A is not particularly limited, and for example, as shown in Figure 1, it is possible to incline the bottom surface of the mixing section 2A, provide a height difference between the separated water inlet section 21A where the separated water is introduced and the mixed water outlet section 22 where the mixed water is discharged, and utilize the potential energy within the mixing section 2A. Other means for forming the separated water flow F1 include using energy such as a pump or gravity to circulate the separated water in the separated water circulation path L1, and providing a device (agitation device, etc.) for forming a flow using the power of a screw or the like in the mixing section 2A. As yet another means, the separated water flow F1 can be formed in the mixing section 2A by the action of a pump 5 (single-shaft screw pump 5) for transporting the mixed water discharged from the mixed water discharge section 22 to the separation section 4 without providing a device (agitation device, etc.) for forming a flow in the mixing section 2A.

[0021] A plurality of means for forming the separated water flow F1 may be provided. For example, in the screen residue transport device 1A in this embodiment, in addition to utilizing potential energy by inclining the bottom surface of the mixer 2A, the separated water flow F1 may be formed near the bottom of the mixer 2A by utilizing energy for circulating the separated water in the separated water circulation path L1. In a specific configuration, the separation unit 4 is installed above ground, and this separation unit 4 is connected to the mixing unit 2A installed underground by a separated water circulation path L1 consisting of piping. Then, the separated water can be circulated through the separated water circulation path L1 by the potential energy of the mixing unit 2A from the separation unit 4. Note that any type of energy may be used for circulating the separated water through the separated water circulation path L1, and a pump or the like may be used.

[0022] The mixer 2A may be provided with various configurations for smoothly transporting the screen residue. For example, a water level gauge 32 may be provided in the mixing section 2A, and a response may be made according to the observed water level. More specifically, it is preferable to provide a control unit that controls the water level in the mixing section 2A according to the measurement result of the water level gauge 32. As an example of the control by the control unit, when the water level in the mixing section 2A drops below a predetermined value, the control unit may take measures such as replenishing water to the mixing section 2A when continuing the transport of the screened residue. This maintains the amount of water necessary for transporting the screened residue in the mixing section 2, thereby realizing stable transport of the screened residue. Other possible responses in response to the observation results of the water level gauge 32 include providing a drain in the mixing section 2A and discharging the residue and mixed water remaining in the mixing section 2A as a drain to the outside of the system as necessary, or providing a drainage section above the mixing section 2A and discharging the water by overflow.

[0023] [Crushing section] The crushing section 3A is used to perform the process of crushing the screen residue. By crushing the screen residue, the transport of the screen residue in the mixing section 2A can be further promoted. Screen residue includes metals and plastics contained in sewage and wastewater, and fibers such as underwear, rags, and absorbent cotton. This screen residue can become entangled in downstream equipment such as pumps, dehydrators, and mixers, causing equipment failure. Therefore, by crushing the screen residue using the crushing section 3A, equipment failure can be prevented. Furthermore, by crushing the screen residue, the efficiency of cleaning the screen residue can be increased.

[0024] The crushing section 3A in this embodiment is installed inside the mixing section 2A as shown in Fig. 1. As the crushing section 3A, a crusher can be used. Here, the crusher used as the crushing section 3A may be of any type, for example, a biaxial crusher having a plurality of crushing blades on a drive shaft, etc. In this embodiment, since the crusher is installed inside the mixing section 2A, a vertical biaxial crusher having a drive shaft installed vertically is particularly preferred. In addition, it is preferable to set up the crusher so that it is inclined with respect to the water surface in the mixing section 2A. More specifically, it is preferable to set up the vertical twin-shaft crusher so that the drive shaft is inclined or perpendicular to the inclined bottom surface of the mixing section 2A. This prevents the screen residue from accumulating upstream of the crusher, and allows the screen residue to easily flow into the crusher. As a result, the crushing of the screen residue can be further promoted.

[0025] The mixed water, which is a mixture of the screen residue crushed in the crushing section 3A and water, is discharged from the mixed water discharge section 22. The mixed water discharged from the mixing section 2A is transported by the pump 5 through the mixed water transport path L2 to the separation section 4, or circulated to the mixing section 2A through the mixed water circulation path L3.

[0026] [Mixed water transport channel] The mixed water discharged from the mixing section 2A through the piping from the mixed wastewater discharge section is connected to the suction port of the pump 5 and pumped. The piping from the discharge port of the pump 5 branches into two, one of which is connected to the mixed water transport path L2 and the other is connected to the mixed water circulation path L3. The pump 5 is for transporting the mixed water discharged from the mixing section 2A to the separation section 4, and is composed of a pipe connecting the mixed water discharge section 22 of the mixing section 2A and the separation section 4. Further, mixed water circulation passage L3 is for circulating the mixed water discharged from mixing section 2A to mixing section 2A, and is composed of a pipe connecting mixed water discharge section 22 of mixing section 2A to mixing section 2A. The two branched pipes are each provided with a valve. A transfer valve 41 is provided in the pipe connected to the mixed water transfer path L2, and a circulating water valve 42 is provided in the pipe connected to the mixed water circulating path L3.

[0027] Until the properties of the screened residue are homogenized, the transport water valve 41 is closed and the flow of mixed water in the mixed water transport path L2 is stopped. At this time, the operation of the separation unit 4 is also stopped. The circulating water valve 42 is opened and the flow of mixed water in the mixed water circulating path L3 is maintained. The mixed water passes through the mixing section 2A equipped with the crushing section 3A, thereby reducing the variation in the properties of the screen residue remaining in the mixed water. The flow of the mixed water in the mixed water circulation line L3 returns from the mixed water discharge section 22 through the mixed water circulation line L13 to the mixing section 2A, passes through the crushing section 3A, and reaches the mixed water discharge section 22. This operation of circulating the mixed water homogenizes the properties of the screen residue in the mixed water. Here, the state in which the properties of the screen residue are homogenized refers to, for example, that the concentration, density, viscosity, etc. are approximately constant. It also refers to a state in which foreign matter in the screen residue is sufficiently crushed into small pieces and dispersed in the mixed water. When the foreign matter in the screen residue is sufficiently crushed into small pieces and dispersed in the mixed water, there is no local change in the apparent specific gravity of the screen residue, and the screen residue as a whole has a homogenous apparent specific gravity. When it is determined that the properties of the screen residue have been homogenized, the circulating water valve 42 is closed, the conveying valve 41 is opened, and the mixed water is conveyed to the separator 4 through the mixed water conveying line L2.

[0028] There are several methods for determining whether the screen residue properties have been homogenized. One method is to judge based on the concentration of the mixed water in the mixing section 2A. As shown in Figures 1 and 2, a concentration meter 31 is provided near the mixed water discharge section 22 of the mixing section 2A. Since mixed water containing screen residue contains various solids, the value of the concentration meter 31 fluctuates. In this method, it is judged that the properties of the screen residue have been homogenized when the indication of the concentration meter 31 reaches or exceeds a predetermined value and a predetermined time has elapsed. In this method, it is judged that the properties of the screen residue have been homogenized. The type of concentration meter 31 is selected from ultrasonic, filter, spectroscopic, and electrical conductivity types depending on the properties of the screen residue.

[0029] The current value of the pump 5 for transporting the mixed water may also be used to determine whether the screen residue properties have been homogenized. For example, if a positive displacement pump used for transporting slurry is used as the pump 5, the solids in the mixed water containing the screen residue, the viscosity of the mixed water, and the current value of the pump 5 also fluctuate. If the screen residue properties are homogenized, the fluctuation in the current value of the pump 5 will decrease. In this method, the screen residue properties are determined to have been homogenized when the current value of the pump 5 reaches or exceeds a predetermined value for a predetermined period of time.

[0030] Furthermore, image analysis may be used to determine whether the screen residue has been homogenized. Images of the surface of the mixed water in the mixing section 2A are captured using a sensor such as a camera, and the screen residue is determined based on the data obtained from the images. For example, the image capture area may be divided into a predetermined number of segments, and the screen residue may be determined to have been homogenized when the reflectance spectrum and color of each segment are homogenized to a predetermined range. The acquired image may be analyzed by a computer, and the reflectance spectrum and color may be homogenized, and a judgment may be automatically made as to whether the properties of the screen residue have been homogenized.

[0031] If it is certain that the operating time required for circulating the screen residue from the mixed water discharge section 22 through the mixed water circulation line L3 to the mixing section 2A until the screen residue properties are homogenized will be a fixed time, the time for circulating the mixed water may be set with a timer. The operating time for circulating the screen residue from the mixed water discharge section 22 through the mixed water circulation line L3 to the mixing section 2A is measured with a timer, and the screen residue properties are deemed to have been homogenized when the specified time has elapsed.

[0032] [pump] In this embodiment, the screen residue transport device 1A is provided with a pump 5 for transporting mixed water. The pump 5 is provided on the mixed water transport path L2 and is used to transport the mixed water discharged from the mixing section 2A to the separation section 4 through the mixed water transport path L2. Considering that the pump 5 is to transport a slurry-like fluid such as the mixed water of the sludge transport device 1A, a single-shaft screw pump is preferable. The single-shaft screw pump is a type of positive displacement pump. In general, the single-shaft screw pump is known to have the advantages of less pulsation during pumping and excellent quantitative accuracy compared to other positive displacement pumps (rotary pumps, etc.). The pump is also used to transport objects with low fluidity.

[0033] Other positive displacement pumps can be applied to the slurry fluid such as the mixed water of the screen residue transport device 1A in this embodiment. A non-clog pump can transport a slurry containing coarse solids. Also, if the screen residue is unlikely to contain powder or solids, a gear pump or a screw pump can be applied.

[0034] [Separation section] The separation section 4 is for carrying out a step of separating the mixed water supplied from the mixer 2A via the mixed water transport passage L2 into screen residue and separated water. The separation section 4 may be any device capable of performing solid-liquid separation, and examples thereof include a drum-type filtration device and a centrifugal separator. The separated water separated in the separation section 4 is supplied to the mixing section 2A through the separated water circulation path L1. As a result, as described above, a separated water flow F1 is formed in the mixing section 2A. Meanwhile, the screen residue separated in the separation section 4 is treated by a dehydrator, a screen residue washer, or the like. The separation section 4 may be supplied with washing water for washing the inside of the apparatus after the solid-liquid separation process.

[0035] As described above, the screened residue transport device 1A in this embodiment homogenizes the properties of the screened residue by circulating the mixed water, and when it is determined that the properties of the screened residue have been homogenized, the circulating water valve 42 is closed, the transport valve 41 is opened, and the mixed water is transported through the mixed water transport path L2 to the separator 4. This makes it possible to prevent malfunctions, overflows, overtorque, and poor solid-liquid separation in the separation section 4, improve solid-liquid separation in the screened residue separation section, and reduce the amount of wash water used in the separator.

[0036] [Second embodiment] FIG. 1 is also a schematic explanatory diagram showing a screen residue conveying device 1A according to a second embodiment of the present invention. The screen residue transporting device 1A according to this embodiment is characterized in that after the start of the introduction of screen residue, mixed water is circulated in the mixed water circulating passage. Incidentally, among the configurations of the screen residue transporting device 1A in this embodiment, the description of the same configurations as those of the screen residue transporting device 1A in the first embodiment will be omitted.

[0037] In the screened residue transport device 1A of this embodiment, when screened residue is dumped from the screened residue discharge machine into the mixing section 2A, the discharge water valve 41 is closed and the circulating water valve 42 is opened, and a circulation operation is started in which the mixed water flows from the mixed water discharge section 22 through the mixed water circulation path L3 and is returned to the mixing section 2A. This is because the screened residue is in the most inhomogeneous state when it is dumped from the screened residue discharge machine into the mixing section 2A. After it has been determined that the properties of the screen residue have been homogenized, the transport water valve 41 is opened, the circulating water valve 42 is closed, and the mixed water is transported to the separation section 4 via the mixed water transport path L2, as in the first embodiment.

[0038] [Third embodiment] FIG. 2 is a schematic explanatory diagram showing a screen residue conveying device 1A according to a third embodiment of the present invention. In the screen residue transport device 1A in this embodiment, the mixed water management unit 51 automatically determines whether the properties of the screen residue have been homogenized, and opens and closes the transport water valve 41 and the circulating water valve 42.

[0039] The mixed water control unit 51 receives data required to determine whether the properties of the screen residue have been homogenized, and issues instruction signals to open and close the transport water valve 41 and the circulating water valve 42 based on that data. Data required to determine whether the properties of the screen residue have been homogenized include, for example, the concentration indication value from the concentration meter 31, the current value of the pump 5, and image data.

[0040] FIG. 3 is an explanatory diagram showing the function of the mixed water management unit 51 according to the third embodiment of the present invention. The mixed water management unit 51 includes a data communication unit 511 , a memory unit 512 , a calculation unit 513 , a valve operation unit 514 , and a display unit 515 . Data communication unit 511 receives data required for judgment, which is acquired from mixing unit 2A. The data received by data communication unit 511 is stored in memory unit 512. In addition to the data received by data communication unit 511, memory unit 512 also stores a reference value that serves as a criterion for judgment and is used for comparison with the obtained data. The calculation unit 513 takes in the data required for judgment and the reference value from the memory unit 512 and performs a comparison calculation. The result of the comparison calculation in the calculation unit 513 is sent to the valve operation unit 514. The valve operation unit 514 issues an instruction signal to open / close the carry water valve 41 and the circulating water valve 42 based on the result of the comparison calculation in the calculation unit 513. The results of the comparison calculation in the calculation unit 513 and the contents of the command signals for opening and closing the carry water valve 41 and the circulating water valve 42 are displayed on the display unit 515 in a visually recognizable format. [Explanation of symbols]

[0041] 1A Screening Residue Conveying Device, 2A Mixing Section, 21A Separated Water Inlet Section, 22 Mixed Water Discharge Section, 3A Crushing Section, 4 Separation Section, 5 Pump, 31 Concentration Meter, 32 Water Level Gauge, 41 Conveyed Water Valve, 42 Circulating Water Valve, 51 Mixed Water Management Section, 511 Data Communication Section, 512 Memory Section, 513 Calculation Section, 514 Valve Operation Section, 515 Display Section, F1 Separated Water Flow, L1 Separated Water Circulation Path, L2 Mixed Water Conveying Path, L3 Mixed Water Circulation Path

Claims

1. A mixing section for mixing the sediment and water; a mixed water circulation path for circulating the mixed water treated in the mixing section to the mixing section; A separation section that separates the mixed water into residue and separated water; a mixed water transport path that transports the mixed water to the separation section; A crushing section for crushing sediment, which is installed inside the mixing section; a valve for switching a flow path of the mixed water from the mixed water circulation path to the mixed water transport path, When it is determined that the properties of the screen residue are homogenized in the mixing section, the flow path of the mixed water is switched from the mixed water circulation path to the mixed water transport path. Sediment transport device.

2. After the start of the introduction of the screen residue, the mixed water is circulated through the mixed water circulation path. The screen residue transport device according to claim 1.

3. The method is characterized in that the mixing unit includes a mixed water management unit that determines whether the properties of the screen residue have been homogenized and switches the flow path of the mixed water from the mixed water circulation path to the mixed water transport path in response to the determination. The screen residue transport device according to claim 1 or 2.

4. A mixing step of mixing the screen residue with water; a mixed water circulating step of circulating the mixed water treated in the mixing section to the mixing step; A separation step of separating the mixed water into a screen residue and a separated water; a mixed water conveying step of conveying the mixed water to the separation step; A crushing step for crushing sediment, which is installed inside the mixing section; a valve for switching a flow path of the mixed water from the mixed water circulation step to the mixed water transport step; When it is determined that the properties of the screen residue are homogenized in the mixing step, the flow path of the mixed water is switched from the mixed water circulation step to the mixed water transport step. Sediment transport method.

Images