Water distribution equipment, sewage system, and water intake system

Abstract

The present invention provides a water distribution device that can be miniaturized, and a sewage system and water intake system that have a water distribution device that can be miniaturized. [Solution] In a water distribution device, if the size of each adjustment tank is designed to be small, the jet of sewage passing through the orifice hole may affect the water level fluctuation. However, since the third orifice hole 24A and the second orifice hole 24B are divided into two parts, the energy of the sewage jet passing through them is dispersed. Furthermore, since the third orifice hole 24A and the second orifice hole 24B are formed offset in opposite directions in a direction perpendicular to the flow direction, the jet of sewage passing through the upstream third orifice hole 24A is attenuated, and the sewage passes through the downstream second orifice hole 24B.

Description

[Technical Field]

[0001] This invention relates to a water distribution device, a sewage system, and a water intake system. [Background technology]

[0002] In a combined sewer system, rainwater from rainfall and wastewater such as domestic sewage are carried in the same pipeline, during rainfall, rainwater and wastewater (hereinafter, "rainwater and wastewater" will also be referred to as "sewage") are allowed to flow into the combined sewer pipe. In this combined sewer system, if more than a predetermined amount of rainwater flows into the combined sewer pipe, it is necessary to divide the sewage in a water distribution device into sewage that flows to the sewage treatment plant via a collection pipe and sewage that is discharged into rivers, etc., via a discharge pipe. For example, Patent Document 1 discloses a device as such a water distribution device having a plurality of adjustment tanks, partition walls provided between each adjustment tank, orifice holes formed in each partition wall, and overflow weirs provided on both sides of the bottom of each adjustment tank facing each other and along the direction of the flow path. In this water distribution system, sewage flowing in from the combined sewer pipe is sequentially passed through each adjustment tank and each orifice hole and then distributed to the collection pipe in a predetermined amount, while sewage is distributed to the discharge pipe by overflowing from each overflow weir. [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Patent No. 6672507 [Overview of the project] [Problems that the invention aims to solve]

[0004] In some cases, the adjustment tanks of the aforementioned water distribution system may have to be fixed in a narrow space, for example, due to limited workspace or difficulty in securing space from adjacent structures.

[0005] However, this water distribution device had a problem: because each partition wall had only one orifice hole, designing each adjustment tank to be small could cause the sewage jets coming out of the orifice holes to affect the water level fluctuations.

[0006] This invention has been made in view of the above circumstances, and aims to provide a water distribution device that can be miniaturized, and a sewage system and water intake system having a water distribution device that can be miniaturized. [Means for solving the problem]

[0007] To achieve the above objective, the water distribution device according to the first aspect of the present invention is: A water distribution device comprising an inlet pipe into which flowing water flows, a collection pipe, and a discharge pipe, which are connected, and which divides the flowing water flowing in from the inlet pipe into flowing water that flows to the collection pipe and flowing water that flows to the discharge pipe, The system comprises a flow path through which water flowing in from the inlet pipe flows out into the collection pipe, a plurality of overflow weirs erected on at least one side of the flow path, a plurality of partition walls provided between the plurality of overflow weirs and between the overflow weirs and the collection pipe, each having an orifice hole, and a plurality of regulating tanks partitioned by the plurality of overflow weirs and the plurality of partition walls, with the discharge pipe into which water flowing over from the plurality of overflow weirs connected below the plurality of regulating tanks. The orifice holes formed in the partition wall between the multiple overflow weirs are characterized by being multiple in number.

[0008] To achieve the above objective, the sewerage system according to the second aspect of the present invention is: A sewerage system comprising a combined sewer pipe into which sewage flows, a collection pipe that carries sewage to a sewage treatment plant, and a discharge pipe, with a water distribution device that divides the sewage flowing in from the combined sewer pipe into sewage that flows to the collection pipe and sewage that flows to the discharge pipe, The water distribution device has a flow path through which sewage flowing in from the combined pipe flows out to the collection pipe, a plurality of overflow weirs erected on at least one side of the flow path, a plurality of partition walls provided between the plurality of overflow weirs and between the overflow weirs and the collection pipe, each having an orifice hole, and a plurality of regulating tanks partitioned by the plurality of overflow weirs and the plurality of partition walls, and the discharge pipe into which sewage overflowing from the plurality of overflow weirs flows is connected below the plurality of regulating tanks. The orifice holes formed in the partition wall between the multiple overflow weirs are characterized by being multiple in number.

[0009] To achieve the above objectives, the water intake system according to the third aspect of the present invention is: A water intake system comprising an inlet pipe into which river water flows, a collection pipe, and a discharge pipe connected together, and having a water distribution device that divides the river water flowing in from the inlet pipe into river water to be discharged into the collection pipe and river water to be discharged into the discharge pipe, The water distribution device comprises a channel through which river water flowing in from the inlet pipe flows out to the collection pipe, a plurality of overflow weirs erected on at least one side of the channel, a plurality of partition walls provided between the plurality of overflow weirs and between the overflow weirs and the collection pipe, each having an orifice hole, and a plurality of regulating tanks partitioned by the plurality of overflow weirs and the plurality of partition walls, with the discharge pipe into which river water overflowing from the plurality of overflow weirs flowing in connected below the plurality of regulating tanks. The orifice holes formed in the partition wall between the multiple overflow weirs are characterized by being multiple in number.

[0010] The plurality of orifice holes may be formed in a direction perpendicular to the flow direction, and may also be formed offset in opposite directions in the direction perpendicular to the flow direction between adjacent partition wall portions. [Effects of the Invention]

[0011] According to the present invention, it is possible to provide a water distribution device that can be miniaturized, and a sewage system and water intake system having a water distribution device that can be miniaturized.

Brief Description of the Drawings

[0012] [Figure 1] (A) is a partial cross-sectional plan view showing the configuration of the water distribution device according to the first embodiment, (B) is a cross-sectional view taken along line BB of (A), and (C) is a cross-sectional view taken along line CC of (A). [Figure 2] (A) is a partial cross-sectional plan view showing the state in which sewage flows into the water distribution device according to the first embodiment, (B) is a cross-sectional view taken along line BB of (A), and (C) is a cross-sectional view taken along line CC of (A). [Figure 3] It is a block diagram showing the configuration of a sewer system having the water distribution device according to the first embodiment of the present invention. [Figure 4] (A) is an explanatory diagram for explaining the arrangement of orifice holes of the water distribution device of Comparative Example 1, (B) is an explanatory diagram for explaining the arrangement of orifice holes of the water distribution device of Comparative Example 2, and (C) is an explanatory diagram for explaining the arrangement of orifice holes of the water distribution device of the example of the present invention. [Figure 5] (A) is a flow condition analysis diagram of the water distribution device of Comparative Example 1 when the inflow rate is the normal inflow rate, (B) is a flow condition analysis diagram of the water distribution device of Comparative Example 2 when the inflow rate is the normal inflow rate, and (C) is a flow condition analysis diagram of the water distribution device of the example of the present invention when the inflow rate is the normal inflow rate. [Figure 6] (A) is a flow condition analysis diagram of the water distribution device of Comparative Example 1 when the inflow rate is the heavy rain peak inflow rate, (B) is a flow condition analysis diagram of the water distribution device of Comparative Example 2 when the inflow rate is the heavy rain peak inflow rate, and (C) is a flow condition analysis diagram of the water distribution device of the example of the present invention when the inflow rate is the heavy rain peak inflow rate. [Figure 7] (A) is a graph showing the time change of the inflow rate, overflow rate, and intercepted amount of the water distribution device of Comparative Example 1, (B) is a graph showing the time change of the inflow rate, overflow rate, and intercepted amount of the water distribution device of Comparative Example 2, and (C) is a graph showing the time change of the inflow rate, overflow rate, and intercepted amount of the water distribution device of the example of the present invention. [Figure 8] It is an analysis diagram showing the longitudinal velocity of the water distribution device of Comparative Example 2 when the inflow rate is the heavy rain peak inflow rate. [Figure 9] It is a partial cross-sectional plan view showing the configuration of the water distribution device according to the second embodiment of the present invention. [Figure 10]This is a partial cross-sectional plan view showing the configuration of a water distribution device according to a third embodiment of the present invention. [Figure 11] This is a partial cross-sectional plan view showing the configuration of a water distribution device according to a fourth embodiment of the present invention. [Figure 12] This is a cross-sectional view showing the configuration of a water distribution device according to a fifth embodiment of the present invention. [Figure 13] This is a block diagram showing the configuration of a water intake system having a water distribution device according to the present invention. [Modes for carrying out the invention]

[0013] A water distribution device according to an embodiment of the present invention will be described below with reference to the drawings.

[0014] (First embodiment) The water distribution device according to the first embodiment will be described with reference to Figures 1 to 3. Figures 1(A) and 2(A) are partial cross-sectional plan views showing only the pipe in cross-section, with the lid of the water distribution device 2 removed. The water distribution device 2 of the first embodiment is used in a combined sewer system 1, for example, as shown in Figure 3. The combined sewer system 1 is a sewer system that carries rainwater from rainfall and wastewater such as domestic wastewater in the same pipeline, a combined sewer pipe.

[0015] The combined sewer system 1 includes a water distribution device 2 and a sewage treatment plant 5. The combined sewer system 1 also includes a combined pipe (inlet pipe) 6 for receiving rainwater and wastewater (sewage) during rainfall and directing the incoming sewage to the water distribution device 2, a discharge pipe 7 for discharging one portion of the sewage distributed by the water distribution device 2 into a public water body W such as a river, a collection pipe (collection pipe) 8 for directing the other portion of the sewage distributed by the water distribution device 2 to the sewage treatment plant 5, and a sewage treatment plant discharge pipe 9 for discharging the purified sewage from the sewage treatment plant 5 into the public water body W. At the sewage treatment plant 5, for example, advanced treatment is performed, which involves sedimentation, biological treatment, and disinfection of the incoming sewage before discharge, and simplified treatment is performed, which involves only sedimentation and disinfection before discharge.

[0016] The water distribution device 2 is a device capable of precisely dividing sewage flowing in from the combined sewer pipe 6 into a predetermined amount of sewage that flows to the sewage treatment plant 5 via the shielding pipe 8, and sewage that is discharged into the public water body W via the discharge pipe 7. As shown in Figures 1 and 2, the water distribution device 2 is erected on a base plate 25 and has a housing 26 with a closed lid 26e, containing three adjustment tanks: a first adjustment tank 2C, a second adjustment tank 2B, and a third adjustment tank 2A. The third adjustment tank 2A ​​is located on the upstream side, the first adjustment tank 2C is located on the downstream side, and the second adjustment tank 2B is located between the third adjustment tank 2A ​​and the first adjustment tank 2C. The first to third adjustment tanks 2C, 2B, and 2A are provided in a continuous sequence.

[0017] A confluence pipe 6 is connected to the upstream side wall 26a of the housing 26, and sewage flows from the confluence pipe 6 into the third adjustment tank 2A. A collection pipe 8 is connected to the downstream side wall 26b of the housing 26, which is opposite to the upstream side wall 26a, and sewage flows from the first adjustment tank 2C into the collection pipe 8. In other words, a flow path 20 is formed through which sewage flowing in from the confluence pipe 6 flows out into the collection pipe 8. Furthermore, a discharge pipe 7 is connected below the collection pipe 8 on the downstream side wall 26b of the housing 26. The discharge pipe 7 is connected to the lower center of the side wall 26b and is located below the first to third adjustment tanks 2C, 2B, and 2A.

[0018] The first to third adjustment tanks 2C, 2B, and 2A are mounted on a base 27. The base 27 is installed between the side walls 26a and 26b of the housing 26. The upper surface of the base 27 is formed in a stepped shape that slopes downward from the upstream side to the downstream side, forming the first to third bottoms 21C, 21B, and 21A of the first to third adjustment tanks 2C, 2B, and 2A. That is, the first to third bottoms 21C, 21B, and 21A are formed to be progressively lower from the upstream side to the downstream side. The third bottom 21A is formed to be longer in the flow direction than the second bottom 21B and the first bottom 21C. In addition, the planar first to third bottoms 21C, 21B, and 21A are formed with their longitudinal ends inclined inward so that the width in the short direction narrows from the upstream side to the downstream side. The longitudinal ends of the first to third bottom sections 21C, 21B, and 21A are formed with an inward inclination because the diameter of the downstream collection pipe 8 is smaller than the diameter of the upstream confluence pipe 6, among other reasons.

[0019] A pair of third overflow weirs 22A are erected opposite each other on both sides of the third bottom 21A of the third regulating tank 2A, along the direction of the flow path. Similarly, a pair of second overflow weirs 22B are erected opposite each other on both sides of the second bottom 21B of the second regulating tank 2B, along the direction of the flow path. Furthermore, a pair of first overflow weirs 22C are erected opposite each other on both sides of the first bottom 21C of the first regulating tank 2C, along the direction of the flow path. Since the first to third overflow weirs 22C, 22B, and 22A are provided on both sides of the flow path 20, the sewage overflowing from the first to third overflow weirs 22C, 22B, and 22A flows down the flow path 20 from both sides.

[0020] The height of the third overflow weir 22A on the upstream side is set to match the water level at which the planned collection amount of sewage flows into the combined pipe 6. The planned collection amount is set as the maximum amount of sewage that can be treated at the sewage treatment plant 5. If the height of the third overflow weir 22A is set higher than the water level at which the planned collection amount of sewage flows into the combined pipe 6, a backwater effect will be induced in the combined pipe 6, resulting in a decrease in the flow capacity of the combined pipe 6 and the accumulation and sedimentation of pollutants within the combined pipe 6. Furthermore, the height of the first overflow weir 22C on the downstream side is set to be higher than the water level of sewage that overflows from the first to third overflow weirs 22C, 22B, and 22A and flows into the housing 26.

[0021] Between the third regulating tank 2A ​​and the second regulating tank 2B (between the third overflow weir 22A and the second overflow weir 22B), a plate-shaped third partition wall 23A is erected in a direction perpendicular to the flow direction. Also, between the second regulating tank 2B and the first regulating tank 2C (between the second overflow weir 22B and the first overflow weir 22C), a plate-shaped second partition wall 23B is erected in a direction perpendicular to the flow direction. Also, between the first regulating tank 2C and the shielding pipe 8 (between the first overflow weir 22C and the shielding pipe 8), a plate-shaped first partition wall 23C is erected in a direction perpendicular to the flow direction. As a result, the first to third adjustment tanks 2C, 2B, and 2A are partitioned by the first to third overflow weirs 22C, 22B, and 22A, and the first to third partition walls 23C, 23B, and 23A.

[0022] The third partition section 23A and the second partition section 23B are installed extending between the side walls 26c and 26d of the housing 26. By installing the third partition section 23A and the second partition section 23B between the side walls 26c and 26d, sewage overflowing from the third overflow weir 22A and the second overflow weir 22B is prevented from falling into the first adjustment tank 2C and causing wave-like effects. The first partition section 23C is provided adjacent to the downstream side wall 26b of the housing 26.

[0023] Two third orifice holes 24A and two second orifice holes 24B are formed in the adjacent third partition wall 23A and second partition wall 23B, respectively. The third orifice holes 24A and the second orifice holes 24B are formed side by side in a direction perpendicular to the flow direction (the width direction of the flow path). Furthermore, the third orifice holes 24A are formed offset in one direction (downward in Figures 1(A) and 2(A)) relative to the center of the flow path 20 in a direction perpendicular to the flow direction, while the second orifice holes 24B are formed offset in the other direction (upward in Figures 1(A) and 2(A)) relative to the center of the flow path 20 in a direction perpendicular to the flow direction. One first orifice hole 24C is formed in the first partition wall 23C.

[0024] Furthermore, a control and inspection section 29 is provided on the lid 26e of the housing 26. The control and inspection section 29 is provided with an inspection hole, allowing inspection of the inside of the housing 26 from the outside.

[0025] Here, we will explain the flow rate control of the water distribution device 2. When it rains heavily or during torrential downpours, the sewage that flows from the combined pipe 6 into the water distribution device 2 is divided as shown in Figure 2(A) into two parts: sewage that passes sequentially through the third adjustment tank 2A, two third orifice holes 24A, the second adjustment tank 2B, two second orifice holes 24B, the first adjustment tank 2C, and the first orifice 24C and flows to the collection pipe 8 with a planned collection amount, and sewage that overflows from the third to first overflow weirs 22A, 22B, and 22C and flows to the discharge pipe 7.

[0026] Conventionally, in water distribution devices, designing the size of each adjustment tank to be small could cause the sewage jet passing through the orifice holes to affect water level fluctuations. However, because the third orifice hole 24A and the second orifice hole 24B are divided into two parts, the energy of the sewage jet passing through them is dispersed. Furthermore, since the third orifice hole 24A and the second orifice hole 24B are formed offset in opposite directions relative to the center of the flow path 20 in a direction perpendicular to the flow path direction, the sewage jet passing through the upstream third orifice hole 24A can be reduced in force, allowing the sewage to pass through the downstream second orifice hole 24B.

[0027] In the water distribution device 2, even if the amount of sewage flowing in from the combined pipe 6 increases, as shown in Figure 2(B), the incoming sewage is sequentially passed through the upstream third adjustment tank 2A, the two third orifice holes 24A, the second adjustment tank 2B, and the two second orifice holes 24B, thereby mitigating the rise in water levels within the adjustment tanks. This reduces the range of fluctuations in the water level in the first adjustment tank 2C, which is located downstream and directly involved in the collection and distribution of sewage, thereby suppressing fluctuations in the amount of sewage distributed to the collection pipe 8.

[0028] In the third adjustment tank 2A, which is located upstream and has a long length in the direction of the flow path, the complex hydraulic phenomena caused by the sewage flowing in from the confluence pipe 6 are limited, and the incoming sewage is controlled to approximately the target water distribution flow rate. Subsequently, the sewage that has passed through the third adjustment tank 2A ​​is sequentially passed through the second adjustment tank 2B and the first adjustment tank 2C on the downstream side, thereby further improving the accuracy of water distribution control and adjusting to the target water distribution flow rate.

[0029] As the amount of sewage flowing into the water distribution device 2 from the confluence pipe 6 increases, the overflow depth of sewage overflowing from the third overflow weir 22A in the third adjustment tank 2A ​​increases rapidly, causing a sensitive reaction. In contrast, in the second adjustment tank 2B, the overflow depth of sewage overflowing from the second overflow weir 22B increases only slightly, and in the first adjustment tank 2C, the overflow depth of sewage overflowing from the first overflow weir 22C does not increase more than the overflow depth overflowing from the second overflow weir 22B, resulting in a slower reaction.

[0030] The amount of sewage diverted by the water distribution device 2 and flowing into the collection pipe 8, which is equal to the planned collection amount, is discharged to the sewage treatment plant 5, where it undergoes advanced treatment and simplified treatment. The sewage purified at the sewage treatment plant 5 is discharged into the public water body W via the sewage treatment plant discharge pipe 9. In addition, the sewage diverted by the water distribution device 2 and flowing into the discharge pipe 7 is also discharged into the public water body W.

[0031] In this embodiment of the water distribution device, the third orifice hole 24A and the second orifice hole 24B are each composed of two orifice holes 24B, and are formed offset in opposite directions in a direction perpendicular to the flow direction. This reduces the influence of the sewage jets passing through on water level fluctuations. As a result, the water distribution device of this embodiment enables more precise water distribution control and can be miniaturized depending on the installation situation. Ultimately, this contributes to the rationalization and labor saving of sewage systems.

[0032] Furthermore, in the water distribution device of this embodiment, first to third overflow weirs 22C, 22B, and 22A are provided on both sides of the flow path 20, which increases the overall length of the weir, stabilizes the hydraulic phenomena, and makes it possible to reduce the size of the housing 26.

[0033] Furthermore, in the combined sewer system of this embodiment, even during heavy rain or downpours, the water distribution device 2 enables more precise water distribution control, allowing for the precise distribution and collection of the target planned amount of sewage. As a result, the combined sewer system of this embodiment can avoid problems such as the merging problem where the merging pipe becomes a merging pipe again to collect water, accidents to pipeline facilities due to excessive merging, and problems at sewage treatment plants such as the discharge of untreated sewage. In addition, the combined sewer system of this embodiment can use a water distribution device 2 that can be made smaller, thus improving its versatility.

[0034] (Examples) The present invention will be described below based on examples, but the present invention is not limited in any way by these examples.

[0035] The accuracy of water distribution control for the water distribution device of the present invention was verified using numerical fluid dynamics analysis. In Example, Comparative Example 1, and Comparative Example 2, analyses were performed with varying conditions for the orifice hole of the water distribution device. The water distribution device was designed for practical use in a combined sewer system. The scale of the water distribution device was based on existing examples of sewer facilities, with the diameter of the combined pipe (inflow pipe) set to 5m, the diameter of the shielding pipe (collection pipe) set to 2.2m, the length of the internal space of the water distribution device in the flow direction set to 12m, and the width of the internal space of the water distribution device set to 10m. In this design, the planned shielding amount was set as the normal sewage inflow volume. 3 Assuming / s, the external force is 67 m³ of sewage inflow during the peak of heavy rainfall. 3 It was assumed to be / s.

[0036] Furthermore, the section length of the combined pipe (inflow pipe) of the water distribution device was set to 50m (10 times the pipe diameter), and an inflow boundary was set at the upstream end of the combined pipe (inflow pipe), with an unsteady flow waveform given as the inflow boundary condition. Specifically, assuming a sudden heavy rainfall, a flow waveform was given in which the amount of sewage inflow increases linearly in a short time (8 minutes) from the normal state where the amount of sewage is the planned collection amount to the peak of the heavy rainfall. In addition, outflow boundaries were set in the collection pipe (collection pipe) and discharge pipe, and the design value of the water level was given as the boundary condition at each outflow boundary.

[0037] The water distribution device of this embodiment differs from the water distribution device of the first embodiment in that it has four adjustment tanks, from the first tank (first adjustment tank) to the fourth tank (fourth adjustment tank), as shown in Figures 4(C) to 6(C). Otherwise, the configuration is a simplified version of the water distribution device of the first embodiment for the purpose of performing numerical fluid analysis. In the water distribution device of this embodiment, as shown in Figure 4(C), two orifice holes for the second to fourth tanks are arranged in the second to fourth partition walls downstream of the second to fourth tanks, aligned in a direction perpendicular to the flow direction (width direction). Furthermore, the fourth and third orifice holes formed in adjacent partition walls are offset in opposite directions relative to the center of the flow path in a direction perpendicular to the flow direction, and similarly, the third and second orifice holes are also offset in opposite directions relative to the center of the flow path in a direction perpendicular to the flow direction. Furthermore, the width of the second to fourth orifice holes in the water distribution device of the example is half the width of the orifice holes in Comparative Examples 1 and 2, which will be described later.

[0038] In the water distribution device of Comparative Example 1, as shown in Figure 4(A), one orifice hole was provided in each of the first to fourth partition walls on the downstream side of the first to fourth tanks. The second and third orifice holes were positioned in the opposite direction to the flow direction, relative to the center of the flow path, offset by half the width of the orifice hole. The first and fourth orifice holes were positioned in the center of the flow path. The rest of the configuration was the same as in the embodiment.

[0039] In the water distribution device of Comparative Example 2, as shown in Figure 4(B), one orifice hole was provided for each of the first to fourth orifice holes on the downstream side of the first to fourth tanks. Furthermore, all of the first to fourth orifice holes were located in the center of the flow path. The other configurations were the same as in the example.

[0040] In the water distribution device of Comparative Example 1, the third orifice hole on the upstream side of the second tank is positioned offset to the left of the flow path, so as shown in Figure 5(A), even with the normal inflow rate of sewage, it overflowed from the left side of the second overflow weir of the second tank. Also, because the second orifice hole on the upstream side of the first tank is positioned offset to the right of the flow path, it overflowed from the right side of the first overflow weir of the first tank. This is because the jet of sewage passing through the third orifice hole collided with the second bulkhead, causing the water surface to rise and overflow from the left side of the nearby second overflow weir. Additionally, the jet of sewage passing through the second orifice hole collided with the first bulkhead, causing the water surface to rise and overflow from the right side of the nearby first overflow weir.

[0041] Furthermore, in the water distribution device of Comparative Example 1, as shown in Figures 6(A) and 7(A), the overflow volume from the sewage overflow weir became excessive from normal times to the peak of heavy rainfall, resulting in a tendency for the amount of water to be blocked to be less than the planned amount.

[0042] In the water distribution device of Comparative Example 2, as shown in Figure 5(B), no sewage overflow occurred when the sewage inflow was at normal levels. However, as shown in Figures 6(B), 7(B), and 8, during the peak of heavy rainfall, the jet that passed through the upstream orifice continued to pass through the downstream orifice without being weakened, resulting in a larger amount of water being blocked than the planned blockage amount, which was the design value.

[0043] In contrast, in the water separation device of the embodiment, as shown in FIGS. 5(C), 6(C) and 7(C), when the sewage inflow is at the normal inflow rate, sewage overflow does not occur. During the heavy rain peak, sewage is overflowed for each of the first to fourth tanks, and the flow rate of the sewage passing through the orifice holes is gradually decreased. As a result, it was found that a higher-precision water separation control is possible compared to Comparative Example 1 and Comparative Example 2. There are two reasons for this. One is that the sewage jet is dispersed because the orifice holes are divided into two. Another reason is that the fourth orifice hole and the third orifice hole are arranged with a reverse shift in the direction perpendicular to the flow path direction, and the third orifice hole and the second orifice hole are also arranged with a reverse shift in the direction perpendicular to the flow path direction. Therefore, as shown in FIG. 8 for the water separation device of Comparative Example 2, the phenomenon that the sewage jet continuously passes from the upstream orifice hole to the downstream orifice hole is prevented.

[0044] The accuracy of the water separation control in the water separation devices of Comparative Example 1, Comparative Example 2 and the embodiment was evaluated by the collection error according to the following formula (1). In the following formula (1), e s is the collection error (percentage), Q s is the collected amount [m 3 / s], and Q s,d is the planned collected amount [m 3 / s]. e s = 100(Q s - Q s,d ) / Q s,d ···(1)

[0045] Table 1 shows the average value of the collection error e [[ID=XX]] s at all inflow rates for all times in the water separation devices of Comparative Example 1, Comparative Example 2 and the embodiment, and the average value of the collection error e [[ID=XX]] s at the maximum inflow rate during the heavy rain peak (600 s to 800 s). The collection error e [[ID=XX]] s is arranged in two ways: all times and during the heavy rain peak, because it is considered to be maximized at the inflow rate during the heavy rain peak.

[0046]

Table 1

[0047] In the water distribution device of Comparative Example 1, the shielding error e in Table 1 s From the average values, it was found that the amount of sewer overflow was excessive, so the amount of sewer collected was smaller than the planned amount of sewer collected. Also, in the water distribution device of Comparative Example 2, the sewer collection error e in Table 1 s From the average values, it was found that the amount of filtration was excessive.

[0048] The water distribution device in the example has a total inflow with a collection error e s The average value is 9.7%, and the blocking error e at maximum inflow rate is s The average value was 11.1%, which was the best accuracy compared to Comparative Examples 1 and 2. In conventional water distribution devices, the shielding error e over the entire time was calculated to be 40-50% in theoretical calculations. s In addition to the occurrence of this, the planned amount of rainfall Q occurs during actual heavy rain. s,d several times the obstruction error e s It has also been pointed out that this can occur. Therefore, the water distribution device of the embodiment enables significantly more precise control of the water distribution flow rate compared to conventional water distribution devices.

[0049] (Second embodiment) A water distribution device according to the second embodiment will be described with reference to Figure 9. In the second embodiment, components similar to those in the water distribution device according to the first embodiment are denoted by the same reference numerals and their descriptions are omitted, while the differences from the first embodiment will be described. In the water distribution device 40 of the second embodiment, the first to third overflow weirs 22C, 22B, and 22A are provided on one side of the flow path 20. In this embodiment, sewage overflowing from the first to third overflow weirs 22C, 22B, and 22A flows down from one side of the flow path 20.

[0050] (Third embodiment) A water distribution device according to the third embodiment will be described with reference to Figure 10. In the third embodiment, components similar to those in the water distribution device according to the first embodiment are denoted by the same reference numerals and their descriptions are omitted, while the differences from the first embodiment will be described. The water distribution device 50 of the third embodiment has two adjustment tanks, a first adjustment tank 5B and a second adjustment tank 5A, and includes a first bottom 51B, a second bottom 51A, a pair of first overflow weirs 52B, a pair of second overflow weirs 52A, a first partition wall 53B, a second partition wall 53A, a first orifice hole 54B, and a second orifice hole 54A. Two second orifice holes 54A are formed side by side in a direction perpendicular to the flow path direction (the width direction of the flow path). By using two adjustment tanks, it is possible to reduce the size of the housing 26.

[0051] (Fourth embodiment) The water distribution device according to the fourth embodiment will be described with reference to Figure 11. In the fourth embodiment, components similar to those in the water distribution device according to the first embodiment are denoted by the same reference numerals and their descriptions are omitted, while the differences from the first embodiment will be described. The water distribution device 60 of the fourth embodiment has a first overflow weir 62B and a second overflow weir 62A provided on one side of the flow path 20, and has two adjustment tanks, a first adjustment tank 6B and a second adjustment tank 6A. The water distribution device 60 also has a first bottom 61B, a second bottom 61A, a first partition wall 63B, a second partition wall 63A, a first orifice hole 64B, and a second orifice hole 64A. Two second orifice holes 64A are formed side by side in a direction perpendicular to the flow path direction (the width direction of the flow path).

[0052] (Fifth embodiment) A water distribution device according to the fifth embodiment will be described with reference to Figure 12. In the fifth embodiment, components similar to those in the water distribution device according to the first embodiment are denoted by the same reference numerals and their descriptions are omitted, while the differences from the first embodiment will be described. In the water distribution device 70 of the fifth embodiment, two third orifice holes 74A and two second orifice holes 74B are formed side by side in the height direction (vertical direction) of the third partition wall 23A and the second partition wall 23B. By dividing the third orifice hole 74A and the second orifice hole 74B into two in this way, the energy of the sewage jet passing through is dispersed. In addition, the third orifice hole 74A and the second orifice hole 74B are formed offset in the height direction between the adjacent third partition wall 23A and the second partition wall 23B. This reduces the force of the sewage jet that has passed through the third orifice hole 74A on the upstream side, allowing the sewage to pass through the second orifice hole 74B on the downstream side.

[0053] Although the present invention has been described above with reference to embodiments, the present invention is not limited to the above embodiments, and various embodiments and modifications are possible. For example, in the first to fifth embodiments described above, an example in which the water distribution device is used in a combined sewer system was explained, but it can also be used in a separate sewer system in which rainwater and wastewater are carried in separate pipelines. For example, by connecting the rainwater pipe (inlet pipe), collection pipe (collection pipe), and discharge pipe of a separate sewer system to the water distribution device, it is possible to precisely distribute and collect the planned amount of rainwater to be collected for non-point load countermeasures. This makes it possible to effectively prevent non-point pollution.

[0054] Furthermore, by using the water distribution device of the present invention in the retention ponds of combined sewer systems and separate sewer systems, it is possible to precisely divide water into the maximum amount of sewage that can be discharged into public water bodies, the maximum amount of rainwater that can be discharged into public water bodies, and the sewage and rainwater to be discharged into the retention pond.

[0055] Furthermore, as shown in Figure 13, the water distribution device of the present invention can also be applied to a water intake system. The water intake system 3 has a water distribution device 30. This water distribution device 30 is connected to an inlet pipe 36 through which river water from the river 31 flows in via a water intake 32, a collection pipe 38 that flows the desired river water to the power plant 33, and a discharge pipe 37 that discharges the river water back into the river 31. The other components of the water distribution device 30 are the same as those of the water distribution device according to the first embodiment.

[0056] In this water intake system, the water distribution device 30 allows for high-precision water distribution of the river water flowing in from the inlet pipe 36 to the power plant 33, which then flows it to the collection pipe 38, into a desired amount of river water for intake and river water for discharge to the discharge pipe 37. Furthermore, this water intake system can also be used to distribute a desired amount of river water to water supply systems or agricultural irrigation canals instead of the hydroelectric power plant 33.

[0057] Furthermore, although the above embodiments and examples describe an example in which two orifice holes are formed in the partition wall, the number of orifice holes is not limited to two; any number is acceptable, and three or more may be formed. By forming multiple orifice holes, the energy of the sewage jet passing through the orifice holes is dispersed.

[0058] Furthermore, in the above embodiments and examples, we have described examples in which two orifice holes are formed offset in opposite directions in a direction perpendicular to the flow direction between adjacent partition walls. However, it is not always necessary to form multiple orifice holes offset in this way. As mentioned above, simply forming multiple orifice holes can provide the effect of dispersing the sewage jet passing through the orifice holes.

[0059] Furthermore, although the above embodiments and examples describe water distribution devices having two to four adjustment tanks, the device may also have five or more adjustment tanks. Having five or more adjustment tanks enables more precise water distribution control. [Explanation of symbols]

[0060] 1. Combined sewer system 3. Water intake system 2,30,40,50,60,70 Water diversion device 5. Sewage treatment plant 6 Confluence pipe (inflow pipe) 36 Inflow pipe 7,37 Outlet pipe 8. Shielding pipe (collection pipe) 38 Collection tube 9. Discharge pipe for sewage treatment plant 20 flow channels 2A Third adjustment tank 2B Second adjustment tank 2C First adjustment tank 21A Third bottom 21B Second bottom 21C First bottom 22A Third overflow weir 22B 2nd overflow weir 22C 1st overflow weir 23A Third bulkhead section 23B Second bulkhead section 23C First bulkhead section 24A, 74A Third orifice hole 24B, 74B Second orifice hole 24C First orifice hole 26 cabinets W Public water area 31 Rivers 32 Water intake 33 Power Plants

Claims

1. A water distribution device comprising an inlet pipe into which flowing water flows, a collection pipe, and a discharge pipe, which are connected, and which divides the flowing water flowing in from the inlet pipe into flowing water that flows to the collection pipe and flowing water that flows to the discharge pipe, The system comprises a flow path through which water flowing in from the inlet pipe flows out into the collection pipe, a plurality of overflow weirs erected on at least one side of the flow path, a plurality of partition walls provided between the plurality of overflow weirs and between the overflow weirs and the collection pipe, each having an orifice hole, and a plurality of regulating tanks partitioned by the plurality of overflow weirs and the plurality of partition walls, with the discharge pipe into which water flowing over from the plurality of overflow weirs connected below the plurality of regulating tanks. A water distribution device characterized in that there are multiple orifice holes formed in the partition wall portion provided between the multiple overflow weirs.

2. The water distribution device according to claim 1, characterized in that the plurality of orifice holes are formed in a direction perpendicular to the flow direction and are offset in opposite directions in the direction perpendicular to the flow direction between adjacent partition wall portions.

3. A sewerage system comprising a combined sewer pipe into which sewage flows, a collection pipe that carries sewage to a sewage treatment plant, and a discharge pipe, with a water distribution device that divides the sewage flowing in from the combined sewer pipe into sewage that flows to the collection pipe and sewage that flows to the discharge pipe, The water distribution device has a flow path through which sewage flowing in from the combined pipe flows out to the collection pipe, a plurality of overflow weirs erected on at least one side of the flow path, a plurality of partition walls provided between the plurality of overflow weirs and between the overflow weirs and the collection pipe, each having an orifice hole, and a plurality of regulating tanks partitioned by the plurality of overflow weirs and the plurality of partition walls, and the discharge pipe into which sewage overflowing from the plurality of overflow weirs flows is connected below the plurality of regulating tanks. A sewerage system characterized in that there are multiple orifice holes formed in the partition wall between the multiple overflow weirs.

4. The sewerage system according to claim 3, characterized in that the plurality of orifice holes are formed in a direction perpendicular to the flow direction, and are offset in opposite directions in the direction perpendicular to the flow direction between adjacent partition wall portions.

5. A water intake system comprising an inlet pipe into which river water flows, a collection pipe, and a discharge pipe connected together, and having a water distribution device that divides the river water flowing in from the inlet pipe into river water that flows to the collection pipe and river water that flows to the discharge pipe, The water distribution device comprises a channel through which river water flowing in from the inlet pipe flows out to the collection pipe, a plurality of overflow weirs erected on at least one side of the channel, a plurality of partition walls provided between the plurality of overflow weirs and between the overflow weirs and the collection pipe, each having an orifice hole, and a plurality of regulating tanks partitioned by the plurality of overflow weirs and the plurality of partition walls, with the discharge pipe into which river water overflowing from the plurality of overflow weirs flowing in connected below the plurality of regulating tanks. A water intake system characterized in that there are multiple orifice holes formed in the partition wall provided between the multiple overflow weirs.

6. The water intake system according to claim 5, characterized in that the plurality of orifice holes are formed in a direction perpendicular to the flow direction and are offset in opposite directions in the direction perpendicular to the flow direction between adjacent partition wall portions.

Images