JP4435064B2 - Pump station system and sewage treatment method in combined sewer - Google Patents

Description

  The present invention relates to a pumping station system, and more particularly to a pumping station system in a combined sewer that collects and treats sewage and rainwater. The present invention also relates to a method for treating sewage in such a combined sewer.

  In combined sewers, sewage discharged from households and factories and rainwater from rainfall are collected in sewer pipes and treated in a sewage treatment plant installed downstream, and then discharged into rivers, seas, and other areas. To be released. Since the sewage pipe described above is installed in an inclined state so that the sewage naturally flows down, a pumping station for pumping the sewage to a predetermined height is provided at a certain depth.

  Here, when a heavy rain occurs, a large amount of rainwater may flow into the sewage pipe so that it cannot be treated at the downstream sewage treatment plant. In such cases, overflow water from the main sewage pipe is introduced into the discharge channel and discharged directly from the pumping station installed in the discharge channel to the discharge area without going through the treatment plant. Is preventing.

  In the initial stage when the rainfall started, the overflow water described above flows into the dry discharge channel, so that the scum stagnated in the discharge channel and the trash stuck to the discharge channel are removed. Sediment and dust may flow into the pump station at once. At the pumping station installed in the discharge channel, the sewage that has flowed in is discharged directly to the discharge area by the pumping pump without going through the treatment plant. There is a risk that dust will be discharged directly into discharge areas such as rivers and the sea, harming the surrounding environment.

  Conventionally, the spillway is dry and properly cleaned to prevent rot and odor due to deterioration of the quality of the remaining water in the spillway, and to prevent sediment and dust (hereinafter referred to as initial dust) in the early stages of rainfall. The initial dust is removed. However, the irrigation canal is a vast facility extending several kilometers or more, and enormous maintenance costs are required to completely dry these irrigation canals and clean the whole. Further, in order to clean the inside of the water discharge channel, the cleaning staff must enter the water discharge channel, but such cleaning inside the water discharge channel is a work accompanied by danger such as lack of oxygen. Furthermore, since it becomes necessary to install a sprinkler tap and an illuminating lamp for cleaning in the water discharge channel, the initial equipment cost increases.

  Also, instead of cleaning the drainage channel in a dry state, a sedimentation basin is provided upstream or downstream of the pumping station, and the initial dust is settled in this sedimentation basin to prevent discharge to the discharge side. It has also been done. In order to sink the initial dust in such a sand basin, it is necessary to ensure the sedimentation of the initial dust by making the flow rate of sewage in the sand basin extremely low.

  However, the pumping station of the underground drainage facility having a discharge channel collects and drains sewage and rainwater in a range of several kilometers or more, and the capacity (drainage amount) of the pumping station is inevitably large. As described above, since the amount of drainage from the pumping station increases, in order to ensure the sedimentation flow velocity of the initial dust in the above-mentioned sand basin, a sand basin having a very large volume is required. For this reason, the cost for securing the site for the sand basin and the civil engineering construction becomes excessive. In addition, many of the initial dusts are relatively light, and it is difficult to completely settle in the sand basin, so that some of the initial dusts may be discharged to the discharge side.

  The present invention has been made in view of the problems of the prior art as described above, and makes it possible to separate and dispose of initial dust such as scum and dust flowing in along with sewage, and these initial dust can be discharged downstream. It is a first object of the present invention to provide a pumping station system that can prevent discharge into the water.

  In addition, the present invention provides a sewage treatment method capable of separating and treating initial dust such as scum and dust from sewage, and preventing the initial dust from being discharged downstream. The purpose of 2.

  In order to achieve the above object, according to the first aspect of the present invention, it is possible to separate and treat the initial dust such as scum and dust flowing in with the sewage, and these initial dusts are discharged into the downstream discharge region. A pumping station system is provided that can prevent this from happening. This pump station system includes a water absorption tank for collecting sewage combined with sewage and rainwater, and a water discharge tank for storing the sewage in the water absorption tank pumped up by a pump and flowing it to a downstream discharge facility. ing. Further, the pumping station system includes a separation tank for storing sewage pumped up in the initial stage of the operation of the pump, and containing sewage and dust from the sewage in the water discharge tank.

  The pumping station system may further include a communication unit that communicates the water discharge tank and the separation tank at a position lower than the floor surface of the discharge facility. In this case, a backflow prevention mechanism for preventing sewage in the separation tank from returning from the separation tank to the water discharge tank may be provided in the communication portion. A plurality of attenuation plates that protrude inward from the inner peripheral surface may be provided in the separation tank. Or you may comprise the said communication part so that the said sewage may be introduced into the said separation tank from the said water discharging tank toward the tangential direction of the said cylindrical separation tank.

  Moreover, the pumping station system may further include a stagnation pond provided adjacent to an upper portion of the side wall of the separation tank, and a communication unit that communicates the separation tank and the stagnation pond. In this case, a backflow prevention mechanism for preventing the sewage from returning from the stagnation pond to the separation tank may be provided in the communication portion. The separation tank may be provided adjacent to both the water discharge tank and the water absorption tank.

  The pump station system further includes a sewer pipe connecting the pump and the water discharge tank, and a return pipe connected to the lower part of the separation tank and returning the sewage remaining in the separation tank to the sewer pipe. You may have. Alternatively, the pumping station system may further include a return pipe that is connected to the lower part of the separation tank and returns sewage remaining in the separation tank directly to the water absorption tank.

  In addition, the pump station system includes a first on-off valve that opens and closes a sewer pipe that connects the pump and the water discharge tank, and a second that opens and closes a sewer pipe that connects the pump and the separation tank. The on-off valve and a control device may be provided. In this case, the control device closes the first on-off valve and opens the second on-off valve at the initial stage of operation of the pump, and guides the sewage in the water absorption tank to the separation tank, and then The first on-off valve is opened and the second on-off valve is opened to guide the sewage in the water absorption tank to the water discharge tank.

  According to the second aspect of the present invention, there is provided a sewage treatment method capable of separating and treating initial dust such as scum and garbage from sewage, and preventing the initial dust from being discharged downstream. Provided. According to this sewage treatment method, sewage combined with sewage and rainwater is collected in the water absorption tank. The sewage in the water absorption tank is pumped up into the water discharge tank by the operation of the pump, and then flows into the discharge facility on the downstream side. Here, of the sewage stored in the water discharge tank through the communication section provided at a predetermined height, the sewage including pump residue and dust that is pumped in the initial stage of the operation of the pump is introduced to the separation tank. It is burned. Thereby, the sewage containing the residue and dust is separated from the sewage in the water discharge tank.

  In this case, the water level of the water tank is measured, and when the measured change rate of the water level of the water tank exceeds a predetermined set value, the flow rate of sewage pumped into the water tank by the pump is suppressed. May be. Further, the flow rate of sewage flowing into the water absorption tank may be measured or predicted, and the flow rate of sewage pumped into the water discharge tank may be suppressed based on the measured or predicted flow rate of sewage.

  According to the third aspect of the present invention, there is provided a sewage treatment method capable of separating and treating initial dust such as scum and garbage from sewage, and preventing the initial dust from being discharged downstream. Provided. According to this sewage treatment method, sewage combined with sewage and rainwater is collected in the water absorption tank. The sewage in the water absorption tank is pumped up into the water discharge tank by the operation of the pump, and then flows into the discharge facility on the downstream side. Here, sewage including residue and dust collected in the initial stage of operation of the pump is introduced into the separation tank, and the water level of the separation tank is measured. After the measured water level of the separation tank exceeds a predetermined set value, sewage in the water absorption tank is introduced into the water discharge tank.

  According to the present invention, it is possible to separate and treat initial dust such as scum and dust flowing in with sewage with a simple and inexpensive structure, and prevent these initial dust from being discharged into the downstream discharge area. can do.

  Hereinafter, an embodiment of a pumping station system according to the present invention will be described in detail with reference to FIGS. 1 to 10. 1 to 10, the same or corresponding components are denoted by the same reference numerals, and redundant description is omitted.

  FIG. 1 is a schematic diagram showing a pumping station system 1 according to the first embodiment of the present invention. As shown in FIG. 1, the pumping station system 1 includes a water absorption tank 10 that collects sewage in which sewage discharged from a home or factory and rainwater merge. A sewage pipe 12 is connected to the water absorption tank 10, and sewage flows into the water absorption tank 10 through the sewage pipe 12.

  On the downstream side of the pumping station system 1, a discharge facility for discharging sewage to a discharge region such as a river or the sea is disposed. This discharge facility is connected to the water absorption tank 10 by a sewage pipe (sewage flow path) 14. Yes. The sewage pipe 14 includes a pump 16 that pumps sewage in the water absorption tank 10 to the height of the discharge facility, a first adjustment valve 18 that adjusts the flow rate of sewage flowing through the sewage pipe 14, and a pressure in the sewage pipe 14. And a water discharge tank 22 for storing sewage to flow into the discharge facility. The pumping pump 16 is connected to a driving device 26 such as an engine, a gas turbine, or an electric motor, and includes a gear mechanism 24 as necessary.

  As shown in FIG. 1, a separation tank 28 is disposed adjacent to the water discharge tank 22. The partition wall 30 that partitions the water discharge tank 22 and the separation tank 28 is formed with a communication port 32 that allows the water discharge tank 22 and the separation tank 28 to communicate with each other. The upper end of the communication port 32 is adjusted so as to be located at a position lower than the floor surface F of the discharge facility. A return pipe 34 for returning the sewage in the separation tank 28 to the water absorption tank 10 is connected to the lower part of the separation tank 28, and the return pipe 34 adjusts the flow rate of the sewage flowing through the return pipe 34. Two regulating valves 36 are provided.

  A bypass pipe 40 branches off from the sewage pipe 14 between the first regulating valve 18 and the pumping pump 16, and the bypass pipe 40 is a treatment facility 38 provided separately from the pumping station system 1. It is connected to the. The bypass pipe 40 is provided with a third adjustment valve 42 that adjusts the flow rate of sewage flowing through the bypass pipe 40.

  In such a configuration, when sewage flows into the water absorption tank 10 from the sewage pipe 12, the pumping pump 16 is driven by the driving device 26. At this time, the first regulating valve 18 is opened, the second regulating valve 36 is closed, and the third regulating valve 42 is closed. As a result, as shown in FIG. 2A, the sewage in the water absorption tank 10 is sent to the water discharge tank 22 by the pumping pump 16 and accumulated in the water discharge tank 22.

  Thus, the water level of the water discharge tank 22 rises with the operation of the pumping pump 16. When the water level of the water discharge tank 22 eventually reaches the height of the lower end of the communication port 32, sewage flows from the water discharge tank 22 through the communication port 32 into the separation tank 28 as shown in FIG. At this time, the sewage flowing into the separation tank 28 from the water discharge tank 22 is sewage containing initial dust such as scum and dust floating on the surface. Therefore, the sewage containing the initial dust such as scum and dust is separated from the sewage in the water discharge tank 22 and stored in the separation tank 28.

  Thereafter, as shown in FIG. 2 (c), the water levels of the water discharge tank 22 and the separation tank 28 rise together with the operation of the pump 16, and the water level of the water discharge tank 22 changes as shown in FIG. 2 (d). When it becomes higher than the floor surface F of the discharge facility, the sewage in the water discharge tank 22 flows out to the discharge facility side. At this time, the water level in the separation tank 28 is in a steady state, stops flowing and stagnates.

  Thus, according to the pump station system 1 of this embodiment, since the sewage containing the initial waste can be separated into the separation tank 28, the sewage not containing the initial waste can be sent to the discharge facility, It is possible to prevent the initial dust from being discharged into the river or the sea.

  In addition, although the position of the upper end of the communication port 32 mentioned above should just be lower than the floor surface F of a discharge facility, in order to enlarge the depth of the separation tank 28 and to increase the quantity of the initial dust which can be stored, It should be as high as possible.

  Here, when the water level of the water discharge tank 22 accompanying the operation of the pumping pump 16 is severe, it becomes difficult to reliably introduce the sewage containing the initial dust into the separation tank 28 as described above. In such a case, it is preferable to perform the following control.

  The pressure of sewage is measured by a pressure gauge 20 provided in the sewage pipe 14, and the water level in the water discharge tank 22 is calculated from the measured value. When the calculated water level is lower than the height of the upper end of the communication port 32, the rate of increase of the water level in the water discharge tank 22 is compared with a predetermined set value. When the rate of increase of the water level exceeds the set value, the flow rate of sewage flowing into the water discharge tank 22 is adjusted (suppressed) to prevent the water level in the water discharge tank 22 from rising rapidly. When the calculated water level is higher than the height of the upper end of the communication port 32, the pumping pump 16 is rated.

  Here, the flow rate adjustment of the sewage may be performed by adjusting the opening degree of the first adjustment valve 18 or may be performed by adjusting the rotation speed or blade angle of the pumping pump 16. Moreover, when a plurality of pumps 16 are provided, the flow rate of sewage may be adjusted by controlling the number of operating pumps. Moreover, in the above-mentioned example, the water level of the water discharge tank 22 is calculated from the measured value of the pressure gauge 20, but a water level meter may be provided in the water discharge tank 22 to directly measure the water level of the water discharge tank 22.

  Further, if the above-described flow rate control is performed even when a large amount of sewage suddenly flows into the water absorption tank 10, there is a high risk that the upstream water discharge channel will overflow. Therefore, the flow rate of the sewage flowing into the water absorption tank 10 is measured or predicted, and when the large amount of sewage suddenly flows into the water absorption tank 10, the above-described flow rate control is not performed, and the pumping pump 16 is rated. May be.

  After sending the sewage in the water absorption tank 10 to the discharge facility as described above, the pumping pump 16 is stopped. Then, for example, the initial dust in the sewage separated in the separation tank 28 by a scraping device 50 (see FIG. 1) such as a bucket is pulled up and processed.

  After the pumping pump 16 is stopped, the sewage remaining in the water discharge tank 22 and the separation tank 28 is preferably returned to the water absorption tank 10. When the drive device 26 is configured by a motor, the sewage can be returned from the water discharge tank 22 and the separation tank 28 to the water absorption tank 10 by rotating the pumping pump 16 in the reverse direction. When the pumping pump 16 is driven using a driving device 26 that is difficult to reversely rotate because of its structure, such as an engine or a gas turbine, for example, the pumping pump 16 is rotated forward and controlled while its rotational speed is controlled. Then, the sewage can be made to flow backward by adjusting the flow rate of the water falling from the discharge-side sewage pipe 14 to the water absorption tank 10.

  The step of returning the sewage remaining in the water discharge tank 22 and the separation tank 28 to the water absorption tank 10 is performed as follows, for example. First, as shown in FIG. 3A, the first regulating valve 18 is opened and the second regulating valve 36 is closed, and the sewage is caused to flow backward. As a result, as shown in FIG. 3B, the sewage above the communication port 32 in the separation tank 28 is also returned to the water absorption tank 10 together with the sewage in the water discharge tank 22. When the water level of the separation tank 28 is lowered to the lower end of the communication port 32, thereafter, only the water level of the water discharge tank 22 is lowered as shown in FIG. After the sewage in the water discharge tank 22 is exhausted, the second regulating valve 36 is opened to return the sewage remaining in the separation tank 28 to the water absorption tank 10 as shown in FIG. Thus, by returning the sewage remaining in the water discharge tank 22 and the separation tank 28 to the water absorption tank 10, the inside of the water discharge tank 22 and the separation tank 28 can be brought into a dry state.

  As shown in FIG. 1, the sewage returned to the water absorption tank 10 is pumped to the treatment facility 38 by one or more additional pumps 60 provided in the water absorption tank 10, and is subjected to appropriate treatment. In this case, as shown in FIG. 1, the sewage pipe 14 and the processing equipment 38 between the first regulating valve 18 and the pumping pump 16 are connected by a bypass pipe 40, and the third regulation is connected to the bypass pipe 40. If the valve 42 is provided, it is not necessary to provide the additional pump 60. That is, if the pumping pump 16 is operated with the first regulating valve 18 closed and the third regulating valve 42 opened, the sewage in the water tank 10 is sent from the water tank 10 to the treatment facility 38 through the bypass pipe 38. be able to.

  In this embodiment, an example has been described in which the return pipe 34 connected to the separation tank 28 is connected to the sewer pipe 14 and the sewage in the separation tank 28 is returned to the water absorption tank 10 using the pumping pump 16. It is not limited to. For example, the return pipe 34 may be directly connected to the water absorption tank 10 to return the sewage in the separation tank 28 directly to the water absorption tank 10.

  Moreover, in the example shown in FIG. 1, although the water discharging tank 22 and the separation tank 28 are comprised by the container-like structure, the structure of the water discharging tank 22 and the separation tank 28 is not restricted to this. For example, the water discharge tank and the separation tank can be configured by a steel pipe obtained by extending the sewer pipe 14.

  Moreover, in this embodiment, although the sewage is introduce | transduced into the separation tank 28 from the spout tank 22 through the communicating port 32 formed in the partition wall 30 which partitions off the spout tank 22 and the separation tank 28, the spout tank 22 and the separation tank The form of the communication portion that communicates with the communication port 28 is not limited to such a communication port 32. For example, the water discharge tank 22 and the separation tank 28 can be communicated with each other by a communication pipe.

  FIG. 4A to FIG. 4E are cross-sectional views showing modifications of the communication port 32 shown in FIG. The example shown in FIGS. 4A to 4E has a backflow prevention mechanism that prevents the sewage containing the initial dust flowing into the separation tank 28 from the water discharge tank 22 from returning to the water discharge tank 22 as much as possible. .

  That is, the communication port 32a shown in FIG. 4A is provided with a check valve 70 that allows the flow from the water discharge tank 22 to the separation tank 28 but prevents the flow from the separation tank 28 to the water discharge tank 22. Yes. In addition, in the communication port 32b shown in FIG. 4B, the upper surface 71 is inclined so that the opening area on the separation tank 28 side is smaller than the opening area on the water discharge tank 22 side. In addition, in the communication port 32c shown in FIG. 4C, the upper surface 72 and the lower surface 73 are inclined so that the opening area on the separation tank 28 side is smaller than the opening area on the water discharge tank 22 side. Furthermore, in the communication port 32d shown in FIG. 4D, the upper surface 74 is inclined similarly to the communication port 32b shown in FIG. 4B, and the upper end of the communication port 32d is formed on the separation tank 28 side of the partition wall 30. A protrusion 75 extending downward is provided so as to cover the communication port 32d. Further, in the communication port 32e shown in FIG. 4 (e), an extension portion 76 that extends downward from the upper end of the communication port 32e to the separation tank 28 side of the partition wall 30 so as to cover the entire communication port 32e. Is provided.

  Further, when sewage flows from the water discharge tank 22 into the separation tank 28, the load and vibration on the separation tank 28 increase due to the sewage falling downward in the separation tank 28. In order to prevent these loads and vibrations, for example, as shown in FIG. 5, a plurality of attenuation plates 80 protruding inward from the inner peripheral surface of the separation tank 28 a may be provided in a step shape. Alternatively, as shown in FIG. 6, the separation tank 28b may be cylindrical, and sewage may be introduced from the communication port 32 toward the tangential direction of the separation tank 28b. According to this structure, the sewage introduced into the separation tank 28b falls along a spiral trajectory as shown by the dotted line in FIG. 6, so that the load and vibration on the separation tank 28 are reduced.

  FIG. 7 is a schematic diagram showing a pumping station system 101 according to the second embodiment of the present invention. As shown in FIG. 7, this pumping station system 101 basically has the same structure as that of the pumping station system 1 of the first embodiment described above, but is adjacent to the separation tank 28 and is a basin 110. Is different from the pumping station system 1 of the first embodiment described above.

  As shown in FIG. 7, a communication port 112 communicating with the reservoir basin 110 is formed in the upper part of the side wall of the separation tank 28. The communication port 112 is provided with a check valve 114 that allows a flow from the separation tank 28 to the reservoir tank 110 but prevents a flow from the reservoir tank 110 to the separation tank 28.

  As described above, the initial dust such as scum stagnating in the water discharge channel and dust adhering to the water discharge channel has a property of floating near the water surface because its specific gravity is small. In the present embodiment, using the property of the initial dust, the initial dust floating on the water surface is trapped in the catchment basin 110 provided adjacent to the upper part of the separation tank 28. With such a configuration, it is possible to pull up the initial dust that has flowed into the water absorption tank 10 to near the ground surface without providing a special device, and it is possible to provide a highly economical and energy-saving pumping station system.

  Further, since a check valve 114 as a backflow prevention mechanism is provided at the communication port 112 that connects the separation tank 28 and the reservoir basin 110, the water level of the separation tank 28 decreases after the sewage is sent to the discharge facility. Even so, the initial dust introduced into the reservoir 110 does not return to the separation tank 28. Instead of the check valve 114, an open / close valve that opens and closes according to the operation of the pumping pump 16 may be used.

  Further, in the present embodiment, as shown in FIG. 7, it is preferable that the scraping device 50 is installed so as to be movable above the water reservoir 110. Or you may make it give the washing | cleaning function to the water reservoir 110 itself and process the initial dust in the water reservoir 110. FIG.

  In the present embodiment, sewage is introduced from the separation tank 28 to the reservoir basin 110 through the connection port 112 formed in the upper part of the side wall of the separation tank 28, but the communication section that communicates the separation tank 28 and the reservoir basin 110. The form is not limited to such contact 112. For example, the separation tank 28 and the reservoir basin 110 may be communicated with each other through a communication pipe.

  FIG. 8 is a plan view showing a pumping station system 201 according to the third embodiment of the present invention, and FIG. 9 is a sectional view taken along line IX-IX in FIG. As shown in FIG. 8, in this pump station system 201, the water absorption tank 10 and the water discharge tank 22 are connected by two sewage pipes 14, and the water absorption tank is provided by a pumping pump 16 provided in each sewage pipe 14. The sewage in 10 is pumped into the water discharge tank 22.

  Moreover, the separation tank 28 in this embodiment is provided so that it may adjoin to both the water absorption tank 10 and the water discharging tank 22, as shown in FIG. 8 and FIG. The water discharge tank 22 and the separation tank 28 are communicated by a communication port 32, and the separation tank 28 and the water absorption tank 10 are configured to be communicated by a return gate (return part) 210. The return gate 210 is opened after discharging the sewage to the discharge facility, whereby the sewage in the separation tank 28 is returned to the water absorption tank 10. Thus, by providing the separation tank 28 so as to be adjacent to both the water absorption tank 10 and the water discharge tank 22, it is possible to effectively use the installation area of the pumping station system 201 and increase the capacity of the separation tank 28. It becomes.

  FIG. 10 is a schematic diagram showing a main part of a pumping station system according to the fourth embodiment of the present invention. As shown in FIG. 10, in this embodiment, the water discharge tank 22 and the separation tank 28 are not connected by the communication port. The sewage pipe 14 extending from the pumping pump 16 branches into a branch pipe 14 a connected to the lower part of the water discharge tank 22 and a branch pipe 14 b connected to the lower part of the separation tank 28. The branch pipe 14a is provided with a first on-off valve 310 that controls the flow rate of sewage flowing through the branch pipe 14a, and the second open / close valve that controls the flow rate of sewage flowing through the branch pipe 14b. A valve 312 is provided.

  In addition, a first pressure gauge 320 is installed at a position closer to the water discharge tank 22 than a branch point between the branch pipe 14a and the branch pipe 14b, and a second pressure gauge 322 is installed at a position closer to the pumping pump 16. ing. The first pressure gauge 320 is used to calculate the water level of the water discharge tank 22, and the second pressure gauge 322 is used to calculate the water level of the separation tank 28. As shown in FIG. 10, the first on-off valve 310, the second on-off valve 312, the first pressure gauge 320, and the second pressure gauge 322 are each connected to the control device 330.

  In such a configuration, first, the pump pump 16 is driven in a state where the first on-off valve 310 is closed and the second on-off valve 312 is opened, whereby sewage in the water absorption tank is introduced into the separation tank 28. . The sewage introduced into the separation tank 28 at this time is sewage containing initial dust such as scum and dust floating on the surface. Therefore, the sewage containing the initial dust such as scum and dust is stored in the separation tank 28.

  At this time, the pressure of sewage is measured by the second pressure gauge 322, and the control device 330 calculates the water level of the separation tank 28 from the measurement value of the second pressure gauge 322. The control device 330 compares the calculated water level with a predetermined set value, and when the calculated water level exceeds the set value, the second open / close valve 312 is closed and the first open / close valve is closed. Open 310. Thereby, the sewage in the water absorption tank is introduced into the water discharge tank 22. FIG. 10 shows the state at this time. Instead of these pressure gauges 320 and 322, a water level gauge may be provided in the water discharge tank 22 and the separation tank 28.

  Thus, according to this embodiment, since the sewage containing the initial dust can be first separated and introduced into the separation tank 28, and the subsequent sewage can be introduced into the water discharge tank 22, the initial waste is thus included. Waste sewage can be sent to the discharge facility, and the initial dust can be prevented from being discharged into the river or the sea.

  Although one embodiment of the present invention has been described so far, it is needless to say that the present invention is not limited to the above-described embodiment, and may be implemented in various forms within the scope of the technical idea.

It is a schematic diagram which shows the pumping station system in the 1st Embodiment of this invention. 2 (a) to 2 (d) are schematic diagrams showing a process of flowing sewage to a discharge facility in the pumping station system shown in FIG. FIG. 3A to FIG. 3D are schematic views showing a process of causing sewage to flow backward in the pumping station system shown in FIG. 4 (a) to 4 (e) are cross-sectional views showing modifications of the communication port in the pumping station system shown in FIG. It is sectional drawing which shows the modification of the separation tank in the pump station system shown in FIG. It is a perspective view which shows the modification of the separation tank in the pump station system shown in FIG. It is a schematic diagram which shows the pumping station system in the 2nd Embodiment of this invention. It is a top view which shows the pumping station system in the 3rd Embodiment of this invention. It is the IX-IX sectional view taken on the line of FIG. It is a schematic diagram which shows the principal part of the pumping station system in the 4th Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,101,201 Pump station system 10 Water absorption tank 12,14 Sewage pipe 16 Pumping pump 18 1st regulating valve 20 Pressure gauge 22 Water discharge tank 24 Gear mechanism 26 Drive apparatus 28 Separation tank 30 Partition wall 32 Communication port 34 Return pipe 36 Second adjustment valve 38 Processing equipment 40 Bypass pipe 42 Third adjustment valve 50 Scooping device 70-76 Backflow prevention mechanism 80 Damping plate 110 Reservoir 112 Contact port 114 Check valve 210 Return gate 310 First on-off valve 312 Second on-off valve 320 First pressure gauge 322 Second pressure gauge F Floor

Claims (16)

A water absorption tank for collecting sewage combined with sewage and rainwater;
A water discharge tank for storing sewage in the water absorption tank pumped up by a pump, and flowing it to a downstream discharge facility;
A pumping station system in a combined sewer system, comprising: a separation tank that separates and stores sewage that is pumped up at an initial stage of operation of the water pump and contains sewage and dust from the sewage in the water discharge tank. .   The pumping station system according to claim 1, further comprising a communication portion that communicates the water discharge tank and the separation tank at a position lower than a floor surface of the discharge facility.   The pump station system according to claim 2, wherein the communication unit includes a backflow prevention mechanism that prevents sewage in the separation tank from returning from the separation tank to the water discharge tank.   The pumping station system according to claim 2, wherein the separation tank has a plurality of attenuation plates protruding inward from the inner peripheral surface.   The pump station system according to claim 2, wherein the communication portion is configured to introduce the sewage from the water discharge tank into the separation tank toward a tangential direction of the cylindrical separation tank. . A basin provided adjacent to the upper part of the side wall of the separation tank;
A communication unit that communicates the separation tank and the reservoir.
The pump station system according to claim 2, further comprising:   The pump station system according to claim 6, wherein the communication unit includes a backflow prevention mechanism that prevents the sewage from returning from the stagnation pond to the separation tank.   The pumping station system according to claim 2, wherein the separation tank is provided adjacent to both the water discharge tank and the water absorption tank. A sewer pipe connecting the pump and the water discharge tank;
A return pipe connected to the lower part of the separation tank and returning sewage remaining in the separation tank to the sewer pipe;
The pumping station system according to any one of claims 1 to 8, further comprising:   The pump station according to any one of claims 1 to 8, further comprising a return pipe connected to a lower part of the separation tank and returning sewage remaining in the separation tank directly to the water absorption tank. system. A first on-off valve for opening and closing a sewer pipe connecting the pump and the water discharge tank;
A second on-off valve for opening and closing a sewer pipe connecting the pump and the separation tank;
In the initial stage of operation of the pump, the first on-off valve is closed and the second on-off valve is opened to guide the sewage in the water absorption tank to the separation tank, and then the first on-off valve is opened to open the first on-off valve. A control device that opens two on-off valves and guides sewage in the water absorption tank to the water discharge tank;
The pumping station system according to claim 1, further comprising:   The pumping station system according to any one of claims 1 to 11, further comprising a scraping device that pulls up residue and dust collected in the separation tank from the separation tank. A sewage treatment method in which sewage combined with sewage and rainwater is collected in a water absorption tank, a pump is operated, the sewage in the water absorption tank is pumped into a water discharge tank, and is flowed to a downstream discharge facility,
Out of the sewage stored in the water discharge tank through the communication portion provided at a predetermined height, the sewage containing pump residue and dust which is pumped up in the initial stage of the operation of the pump is introduced into the separation tank. A sewage treatment method characterized by separating from sewage in a water tank. Measure the water level in the water tank,
The sewage treatment method according to claim 13, wherein when the measured change rate of the water level of the water discharge tank exceeds a predetermined set value, the flow rate of sewage pumped up by the water pump into the water discharge tank is suppressed. Measure or predict the flow rate of sewage flowing into the water tank,
The sewage treatment method according to claim 14, wherein a flow rate of sewage pumped into the water discharge tank is suppressed based on the measured or predicted flow rate of sewage. A sewage treatment method in which sewage combined with sewage and rainwater is collected in a water absorption tank, a pump is operated, the sewage in the water absorption tank is pumped into a water discharge tank, and is flowed to a downstream discharge facility,
Introducing sewage including residue and dust collected in the initial stage of operation of the pump to the separation tank,
Measuring the water level in the separation tank,
A sewage treatment method, wherein sewage in the water absorption tank is introduced into the water discharge tank after the measured water level of the separation tank exceeds a predetermined set value.

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