Automatic cut-off and anti-backflow device for drainage

Abstract

The invention belongs to the field of municipal drainage, and particularly relates to a drainage automatic shutoff and anti-backflow device which comprises a main well chamber and an auxiliary well chamber, a shutoff valve is arranged in the main well chamber and connected with a shutoff sewage pipe, the shutoff valve comprises a buoyancy box, a connecting rod, a conical valve element, a sealing disc and a balance weight lead block, and a valve body is arranged between the conical valve element and the buoyancy box and connected with the connecting rod. The side, away from the intercepting sewage pipe, of the valve body is a closed end. The shutoff valve can dynamically control the conical valve element to move up and down through buoyancy of the buoyancy box according to liquid level changes, dynamic shutoff is achieved, river channel water backflow at the high water level of a river channel can be eradicated through the backflow-preventing structure, and meanwhile the designed backflow-preventing flap valve improves the defects that a traditional rainwater backflow-preventing device is large in dead weight opening resistance and high in reliability by means of the submerged suspension characteristic. And the drainage performance of the drainage pipe is not completely exerted.

Description

Technical Field

[0001] This invention belongs to the field of municipal drainage, and in particular relates to an automatic drainage interception and backflow prevention device. Background Technology

[0002] Rivers are vital urban flood control and drainage systems, ensuring urban safety during the flood season and serving as scenic water features for public recreation. Due to their physical separation, many riverside roads have main sewage interceptors to reduce sewage discharge. However, some cities currently have combined sewer systems intercepting sewage flowing into the river. During the flood season, river outlets are often below the water level, leading to backflow. Because the interceptor pipes are connected to the sewage pipes, large amounts of river water enter the sewage network, increasing the load on sewage treatment plants. Traditional interception methods are mostly fixed and do not limit the interception volume. During the flood season, rainwater continuously flows into sewage treatment plants, increasing the sewage load and degrading water quality. Traditional backflow prevention methods often use gates or flap gates, which suffer from high resistance or inconvenient operation, affecting the performance of the sewage network. In view of the above problems, this paper proposes to develop an anti-backflow device with automatic interception function and low opening resistance. Summary of the Invention

[0003] The problem to be solved by the present invention is to overcome the shortcomings of the prior art and provide an automatic drainage interception and backflow prevention device.

[0004] This invention is achieved through the following technical solution: An automatic drainage interception and backflow prevention device includes a main well chamber and an auxiliary well chamber. A guide channel and an interception channel are installed in the main well chamber. The guide channel is connected to a merging pipe, and the intercepting sewage pipe is connected to the main well chamber. The other end of the guide channel is connected to the auxiliary well chamber. An anti-backflow flap gate is installed in the auxiliary well chamber at a position corresponding to the guide channel. A interception valve is installed in the main well chamber and connected to the intercepting sewage pipe. The interception valve includes a buoyancy box. A connecting rod is fixedly connected downwards in the middle of the lower surface of the buoyancy box. A conical valve core is fixed at the bottom end of the connecting rod. A sealing disc is fixed to the bottom surface of the conical valve core, and a counterweight lead block is fixed to the bottom surface of the sealing disc. A valve body is provided between the conical valve core and the buoyancy box. The connecting rod passes through the valve body. The valve body is hollow inside. A guide tube is provided on the upper surface of the valve body, and a limiting sealing short tube is provided on the lower surface of the valve body. The maximum diameter of the conical valve core is not greater than the inner diameter of the limiting sealing short tube, and the diameter of the sealing disc is greater than the outer diameter of the limiting sealing short tube. The side of the valve body away from the intercepting sewage pipe is a closed end.

[0005] Preferably, the guide channel is divided into a horizontal flow section and a rapid flow section, with the rapid flow section inclined downwards and facing the auxiliary well chamber side.

[0006] Preferably, the height of the lowest point of the rapid flow section is 40-60 cm lower than the height of the lowest point of the horizontal flow section.

[0007] Preferably, the top of the intercepting trough is lower than the top of the guiding trough but higher than the bottom of the guiding trough, and the bottom of the intercepting trough is lower than the bottom of the guiding trough.

[0008] Preferably, the density of the anti-backflow flap is 1.05-1.1 times that of water.

[0009] Preferably, the conical valve core is made of rigid plastic.

[0010] Preferably, the maximum diameter of the conical valve core is 1-1.5 cm smaller than the inner diameter of the limiting sealing short tube.

[0011] Preferably, the diameter of the sealing disc is 2-4 cm larger than the outer diameter of the limiting sealing short tube.

[0012] Preferably, the inner diameter of the guide tube is 2-3 mm larger than the diameter of the connecting rod.

[0013] Preferably, the upper surface of the valve body is flush with the bottom of the intercepting groove.

[0014] The automatic drainage interception and backflow prevention device of this invention features an additional interception valve that dynamically controls the up-and-down movement of the conical valve core based on changes in liquid level and the buoyancy of the buoyancy box, achieving dynamic interception. Simultaneously, the improved backflow prevention structure submerges the guide channel and the backflow prevention flap gate, utilizing submerged suspension characteristics to overcome the shortcomings of traditional rainwater backflow prevention flap gates, which suffer from high opening resistance due to their own weight and incomplete drainage performance. Attached Figure Description

[0015] Figure 1 This is a top view of this embodiment; Figure 2 for Figure 1 Sectional view of AA; Figure 3 for Figure 1 BB section view; Figure 4 for Figure 1 CC section view; Figure 5 This is a schematic diagram of the shut-off valve structure in this embodiment; Figure 6 This is a schematic diagram of the shut-off valve from another angle in this embodiment; Figure 7 This is a schematic diagram of the valve body structure of the throttling valve in this embodiment; Figure 8 This is a schematic diagram of the buoyancy box structure in this embodiment; Figure 9 This is a schematic diagram of the flow guide channel and flow interception channel in this embodiment.

[0016] In the diagram, 1 is the intercepting sewage pipe, 2 is the merging pipe, 3 is the intercepting trough, 4 is the backflow prevention flap valve, 5 is the scum baffle filter screen, 6 is the buoyancy box, 7 is the conical valve core, 8 is the sealing disc, 9 is the valve body, 10 is the connecting rod, 11 is the limiting sealing short pipe, 12 is the counterweight lead block, 13 is the guide pipe, 14 is the horizontal flow section, 15 is the rapid flow section, and 16 is the diversion trough. Detailed Implementation

[0017] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some embodiments of the present invention, but not all embodiments.

[0018] A conventional backflow prevention device includes a main well chamber and an auxiliary well chamber, separated by a partition wall. A guide channel 16 and an intercepting channel 3 are installed in the main well chamber. One end of the guide channel 16 connects to a confluence pipe 2, which serves as the inlet pipe. The other end of the guide channel 16 connects to the auxiliary well chamber. An intercepting sewage pipe 1 connects to the main well chamber, and the intercepting sewage pipe 1 is perpendicular to the confluence pipe 2. An anti-backflow flap gate 4 is installed in the auxiliary well chamber at the position corresponding to the guide channel 16. The anti-backflow flap gate 4 is mounted on the partition wall, which has holes corresponding to the anti-backflow flap gate 4. These holes connect the guide channel 16 and the auxiliary well chamber, which is connected to the river channel via a drainage pipe. The existing structural design of backflow prevention devices will not be elaborated here; only the improvements of this invention on the existing structure will be described below.

[0019] This invention includes a shut-off valve installed in the main well chamber, which is connected to the shut-off sewage pipe 1, as shown in the attached diagram. Figure 5As shown, the shut-off valve includes a buoyancy box 6. A connecting rod 10 is fixedly connected downwards to the middle of the lower surface of the buoyancy box 6. A conical valve core 7 is fixed to the bottom end of the connecting rod 10. A sealing disc 8 is fixed to the bottom surface of the conical valve core 7, and a counterweight lead block 12 is fixed to the bottom surface of the sealing disc 8. A valve body 9 is provided between the conical valve core 7 and the buoyancy box 6. The connecting rod 10 passes through the valve body 9, which is hollow inside. A guide tube 13 is provided on the upper surface of the valve body 9. The guide tube 13 communicates with the interior of the valve body 9 and allows the connecting rod 10 to slide up and down, limiting the sliding direction of the connecting rod 10. To facilitate the smooth up and down sliding of the connecting rod 10, the inner diameter of the guide tube 13 is preferably 2-3 mm larger than the diameter of the connecting rod 10. A limiting sealing short tube 11 is provided on the lower surface of the valve body 9 and communicates with the interior of the valve body 9. The maximum diameter of the conical valve core 7 is no greater than the inner diameter of the limiting sealing short pipe 11, while the diameter of the sealing disc 8 is greater than the outer diameter of the limiting sealing short pipe 11. The conical valve core 7 can enter the limiting sealing short pipe 11 to seal it, thereby achieving gradual flow interception. The sealing disc 8 can completely seal the limiting sealing short pipe 11, achieving complete flow interception. The side of the valve body 9 facing the intercepting sewage pipe 1 is connected to the intercepting sewage pipe 1 through a flange. The intercepting sewage pipe 1 is internally connected to the valve body 9, and the side of the valve body 9 away from the intercepting sewage pipe 1 is the closed end.

[0020] The aforementioned intercepting valve preferably has a maximum buoyancy of buoyancy tank 6 in water that is not less than three times the total weight of buoyancy tank 6, conical valve core 7, connecting rod 10, counterweight 12, and sealing disc 8. That is, the maximum buoyancy of buoyancy tank 6 is ≥ 3 * (weight of buoyancy tank 6 + weight of conical valve core 7 + weight of connecting rod 10 + weight of counterweight 12 + weight of sealing disc 8). This ensures that conical valve core 7 can close normally at high water levels, preventing a large amount of rainwater from entering the intercepting sewage pipe 1. The dimensions and buoyancy of buoyancy tank 6 are designed according to actual conditions. In this embodiment, the dimensions of buoyancy tank 6 are 0.45m (length), 0.45m (width), and 0.2m (height). The maximum buoyancy of buoyancy tank 6 is approximately 400N (F is the maximum buoyancy of buoyancy tank 6, F = ρ * g * V). 排 ρ is the density of water, 1000 kg / m³ 3 g is the acceleration due to gravity, 9.8 m / s². 2 V 排 (This refers to the volume of buoyancy box 6).

[0021] The aforementioned conical valve core 7 is preferably made of rigid plastic. Preferably, the weight of the bottom counterweight lead block 12 is greater than 1.5 times the sum of the buoyancy of the conical valve core 7 in water plus the weight of the buoyancy box 6, the connecting rod 10, and the sealing plate 8, that is, the buoyancy of the conical valve core 7 in water > 1.5 * (buoyancy of the conical valve core 7 in water + weight of the buoyancy box 6 + weight of the connecting rod 10 + weight of the sealing plate 8).

[0022] The maximum diameter of the preferred conical valve core 7 is 1-1.5 cm smaller than the inner diameter of the limiting sealing short tube 11 to avoid jamming of the conical valve core 7 and to gradually limit the flow. Preferably, the diameter of the sealing disc 8 is 2-4 cm larger than the outer diameter of the limiting sealing short tube 11 to ensure the maximum lift of the conical valve core 7 and to achieve flow throttling and sealing.

[0023] The upper surface of the preferred valve body 9 is flush with the bottom of the intercepting groove 3.

[0024] This embodiment also improves the existing anti-backflow structure design. First, the guide channel 16 is improved by designing it as a horizontal flow section 14 and a rapid flow section 15, as shown in the attached figure. Figure 2 As shown, the bottom height of a conventional guide channel 16 is uniform. In this embodiment, the guide channel 16 is designed as two sections. One section is the conventional design, where the bottom of the guide channel 16 is horizontal; this section is called the horizontal section 14. The bottom height of the horizontal section 14 is uniform. The other section is designed as a sloping section, where the bottom of the guide channel 16 gradually slopes downwards from the horizontal section 14; this section is called the rapid flow section 15. The lowest point of the rapid flow section 15 is 40-60cm lower than the lowest point of the horizontal section 14, meaning the lowest point of the rapid flow section 15 is 40-60cm lower than the lowest point of the confluence pipe 2. The height difference between the rapid flow section 15 and the horizontal section 14 can be specifically set according to actual conditions. The intercepting channel 3 is set on the horizontal section 14 of the guide channel 16. In this embodiment, the cross-section of the guide channel 16 is semi-circular, and the diameter of the guide channel 16 is equal to the diameter of the confluence pipe. The intercepting channel 3 is perpendicular to the guide channel 16 and is connected to the guide channel 16, as shown in the attached figure. Figure 9 As shown, the top of the intercepting trough 3 is lower than the top of the guiding trough 16 but higher than the bottom of the guiding trough 16, and the bottom of the intercepting trough 3 is lower than the bottom of the guiding trough 16. Preferably, the top of the intercepting trough 3 is 30cm lower than the top of the guiding trough 16, and the bottom of the intercepting trough 3 is 40-70cm lower than the bottom of the guiding trough 16. In this embodiment, the intercepting trough 3 is 30cm wide and is located 30cm from the inlet. 20cm behind the intercepting trough 3 is the rapid flow section 15. The partition wall corresponding to the rapid flow section 15 has holes, and the auxiliary well chamber has an anti-backflow flap door 4 at the position corresponding to the holes. The anti-backflow flap door 4 corresponds to the rapid flow section 15. Due to the sinking design of the rapid flow section 15, the height of the corresponding anti-backflow flap door 4 is also reduced accordingly, forming a synchronous sinking design. More preferably, the material used for the anti-backflow flap gate 4 has a density slightly higher than that of water. The material density of the anti-backflow flap gate 4 is approximately 1.05-1.1 times that of water. In this embodiment, the anti-backflow flap gate 4 is designed as a lightweight flap gate, which reduces the opening resistance of the valve core and avoids the defect of the valve core floating and being unable to close.

[0025] To prevent large particles and floating debris from clogging and interfering with the automatic interception device in the combined sewer pipe 2, this embodiment includes a scum baffle filter 5 in the main manhole. The scum baffle filter 5 ensures the smooth passage of combined rainwater and sewage while blocking floating debris from passing through. The bottom of the scum baffle filter 5 is fixed to the bottom surface of the main manhole. Preferably, the upper end of the scum baffle filter 5 is 50cm higher than the upper end of the combined sewer pipe 2.

[0026] The interception process is as follows: Figure 4 As shown, during normal operation, the combined sewer 2 is entirely filled with sewage, and the sewage volume is relatively fixed. When there is no rainfall, the sewage is completely intercepted by the interception channel 3 and enters the intercepting sewage pipe 1. When the rainfall is not too heavy, the combined sewer 2 is filled with combined rainwater and sewage. All combined sewage less than the designed interception flow rate is intercepted by the interception channel 3 and enters the intercepting sewage pipe 1. When the rainfall increases and the water level in the pipe rises, exceeding the designed interception flow rate, some of the combined water overflows the interception channel 3 and is discharged into the river through the anti-backflow flap gate 4. When the water volume further increases and exceeds the set liquid level of the buoyancy box 6, the buoyancy box 6 begins to drive the conical... When valve core 7 floats up, connecting rod 10 moves upward along guide tube 13 on the upper part of valve body 9. Conical valve core 7 gradually enters the limiting sealing short tube 11 and begins to gradually limit the flow rate. When high water level closure occurs, conical valve core 7 completely enters the limiting sealing short tube 11 and closes the lower part of valve body 9 through sealing disc 8. When the closing water level is reached, the closure valve closes, and all the combined rainwater is discharged downward and no longer enters the intercepting sewage pipe 1. When the rainfall decreases and the water level drops below the set liquid level, conical valve core 7 gradually falls down, and the closure valve gradually opens until the flow is completely blocked.

[0027] Backflow prevention process: During normal operation, when the river water level is low, all sewage is intercepted, and the backflow prevention flap gate 4 does not operate. During rainfall, if the designed interception flow is not exceeded, all combined sewage is intercepted, and the backflow prevention flap gate 4 does not open. When the water volume increases and overflow occurs, the backflow prevention flap gate 4 opens in one direction, discharging water into the river. Because the height of the rapid flow section 15 is lower than that of the horizontal flow section 14, the guide channel 16 partially sinks, and the backflow prevention flap gate 4 also sinks synchronously (its height is lower than the normal design position). The backflow prevention flap gate 4 is partially submerged in the water body and is in a suspended state. In addition, the density of the backflow prevention flap gate 4 is only slightly greater than that of the water body. Under the impact of the overflow water flow, the backflow prevention flap gate 4 is in a state of minimum resistance, that is, in a suspended open state, ensuring that the drainage performance of the drainage pipe is fully utilized. When a high water level backflow occurs at the discharge outlet and the river begins to backflow, the backflow prevention flap gate 4 can quickly fall back and close under the impact of the backflow water and its own weight, thus playing a role in preventing backflow.

[0028] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; those skilled in the art should understand that modifications can still be made to the technical solutions described in the above embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. An automatic drainage interception and backflow prevention device, comprising a main well chamber and an auxiliary well chamber, wherein a guide channel (16) and an interception channel (3) are provided in the main well chamber, the guide channel (16) is connected to a merging pipe (2), the interception sewage pipe (1) is connected to the main well chamber, the other end of the guide channel (16) is connected to the auxiliary well chamber, and an anti-backflow flap gate (4) is installed in the auxiliary well chamber at the position corresponding to the guide channel (16), characterized in that: A shut-off valve is installed in the main well chamber. The shut-off valve is connected to the shut-off sewage pipe (1). The shut-off valve includes a buoyancy box (6). A connecting rod (10) is fixedly connected downward in the middle of the lower surface of the buoyancy box (6). A conical valve core (7) is fixed at the bottom end of the connecting rod (10). A sealing disc (8) is fixed on the bottom surface of the conical valve core (7). A counterweight lead block (12) is fixed on the bottom surface of the sealing disc (8). A valve body (9) is provided between the conical valve core (7) and the buoyancy box (6). The connecting rod (10) passes through the valve body (9). The valve body (9) is hollow inside. A guide tube (13) is provided on the upper surface of the valve body (9). A limiting sealing short tube (11) is provided on the lower surface of the valve body (9). The maximum diameter of the conical valve core (7) is not greater than the inner diameter of the limiting sealing short tube (11). The diameter of the sealing disc (8) is greater than the outer diameter of the limiting sealing short tube (11). The side of the valve body (9) away from the shut-off sewage pipe (1) is a closed end.

2. The automatic drainage interception and backflow prevention device according to claim 1, characterized in that: The guide channel (16) is divided into a horizontal flow section (14) and a rapid flow section (15). The rapid flow section (15) is inclined downward and faces the auxiliary well chamber.

3. The automatic drainage interception and backflow prevention device according to claim 2, characterized in that: The height of the lowest point of the rapid flow section (15) is 40-60 cm lower than the height of the lowest point of the horizontal flow section (14).

4. The automatic drainage interception and backflow prevention device according to claim 1 or 2, characterized in that: The top of the intercepting trough (3) is lower than the top of the guide trough (16) and higher than the bottom of the guide trough (16), and the bottom of the intercepting trough (3) is lower than the bottom of the guide trough (16).

5. The automatic drainage interception and backflow prevention device according to claim 1 or 2, characterized in that: The density of the backflow prevention flap (4) is 1.05-1.1 times that of water.

6. The automatic drainage interception and backflow prevention device according to claim 1 or 2, characterized in that: The conical valve core (7) is made of hard plastic.

7. The automatic drainage interception and backflow prevention device according to claim 1 or 2, characterized in that: The maximum diameter of the conical valve core (7) is 1-1.5 cm smaller than the inner diameter of the limiting sealing short tube (11).

8. The automatic drainage interception and backflow prevention device according to claim 1 or 2, characterized in that: The diameter of the sealing disc (8) is 2-4 cm larger than the outer diameter of the limiting sealing short tube (11).

9. The automatic drainage interception and backflow prevention device according to claim 1 or 2, characterized in that: The inner diameter of the guide tube (13) is 2-3 mm larger than the diameter of the connecting rod (10).

10. The automatic drainage interception and backflow prevention device according to claim 1 or 2, characterized in that: The upper surface of the valve body (9) is flush with the bottom of the intercepting groove (3).

Images