Water distribution tank for secondary sedimentation tank with weekly inflow and outflow, secondary sedimentation tank and water distribution method

Abstract

The present invention provides a secondary sedimentation tank water distribution trough with circumferential inlet and outlet, a secondary sedimentation tank and a water distribution method. The secondary sedimentation tank water distribution trough with circumferential inlet and outlet comprises: a water distribution channel, a water inlet channel and a flow control plate. The water distribution channel is arranged along the wall of the secondary sedimentation tank, and a plurality of water distribution pipes are arranged at the bottom; the water inlet channel is connected with the water distribution channel; the flow control plate is arranged at the intersection of the water distribution channel and the water inlet channel, and one end can be rotatably arranged on the side wall of the water distribution channel away from the water inlet channel, and the other end can be arbitrarily docked on the side wall of the water inlet channel or any position inside. The secondary sedimentation tank water distribution trough with circumferential inlet and outlet provided by the present invention, through the arrangement of the flow control plate, makes the partition wall between the head end and the tail end of the water distribution channel into the form of a movable baffle, switches the position of the flow control plate at a regular time, and regularly removes the silt in the water distribution channel through the inlet flow, thereby ensuring that the water distribution channel is always in a clean state, and basically avoiding the occurrence of siltation.

Description

Technical Field

[0001] The present invention relates to the technical field of sewage treatment, and in particular to a secondary sedimentation tank with a peripheral inlet and outlet water distribution trough, a secondary sedimentation tank and a water distribution method. Background Art

[0002] Sedimentation tank is a common structure for separating suspended solids. Secondary sedimentation tank is an important part of activated sludge system. Its function is to separate sludge, clarify, concentrate and return activated sludge to mixed liquor. Sedimentation tank is usually divided into three types according to the direction of water flow in the tank: horizontal flow sedimentation tank, vertical flow sedimentation tank and radial flow sedimentation tank.

[0003] Radial flow secondary sedimentation tanks are mostly circular, with the water inlet in the center and the outlet in the periphery. The water flows horizontally in the tank and radiates to the surrounding areas. As the water flow cross-sectional area continues to increase, the water flow speed in the tank gradually slows down from the center to the surrounding areas, and is discharged to the outside through the outlet trough around the secondary sedimentation tank to complete the entire sedimentation process. The central water inlet method has a simple structure, but the water distribution is uneven.

[0004] The peripheral inlet and outlet secondary sedimentation tank is an improvement on the water distribution method of the radial flow secondary sedimentation tank, and is widely used in the current design of secondary sedimentation tanks in urban sewage plants. The peripheral inlet and outlet secondary sedimentation tank adopts the peripheral water inlet method. A peripheral structured water distribution trough is set along the circular wall of the secondary sedimentation tank. There are several water distribution pipes distributed at the bottom of the trough. The mixed liquid in the aeration tank enters the secondary sedimentation tank water distribution trough through the water inlet pipe and flows along the water distribution trough. During the flow, it enters the secondary sedimentation tank evenly from the water distribution pipe. Through certain flow direction control measures in the tank, the inlet water moves to the center of the tank, and after reaching a certain position, it turns back to move to the periphery of the tank, and the water is discharged through the water outlet troughs arranged around the tank, so as to achieve uniform water distribution to the secondary sedimentation tank.

[0005] Compared with the central water inlet secondary sedimentation tank, the peripheral inlet and outlet secondary sedimentation tank adopts the peripheral water inlet method, which can make the distribution of the inlet water more uniform and better ensure the sedimentation effect of the secondary sedimentation tank. However, the commonly used water distribution method of the peripheral inlet and outlet secondary sedimentation tank in the prior art is: after the mixed liquid in the aeration tank enters the water distribution trough, it flows in one direction along the channel, distributing water while moving forward, running a circle along the secondary sedimentation tank, and returning to the position of the water inlet point to complete the entire water distribution process. The starting point and the end of the water inlet are separated by a partition wall (currently all related settings are fixed structures) to ensure that the water inlet flows in one direction.

[0006] A significant problem with this water distribution method is that as the incoming water moves forward in the water distribution tank, the amount of water flowing forward in the channel gradually decreases due to the continuous flow of water through the water distribution pipe into the secondary sedimentation tank, and the flow rate basically drops to 0 at the end. This flow method brings some significant problems: First, the flow rate in the second half of the channel is already lower than the non-silting flow rate of the water flow, and a large amount of activated sludge in the mixed liquor of the aeration tank will be significantly deposited in the second half of the channel. If maintenance is not timely, it may cause some drainage pipes in the second half of the channel to be blocked, resulting in uneven water distribution; secondly, due to the deposition of activated sludge in the channel, after a certain period of time, the sludge will ferment and produce gas and float up, making the channel sensory poor, and there may be a phenomenon of black mud overflowing to the side of the water outlet tank, resulting in poor water discharge effect, and regular manual cleaning and maintenance are required to ensure stable operation.

[0007] The general solution to the above problem is to set the water distribution trough into a variable cross-section channel, that is, to gradually reduce the cross-sectional width or depth of the water distribution trough along the water flow direction to speed up the water flow speed in the second half, thereby reducing the clogging phenomenon in the second half of the channel. However, this solution does not fundamentally solve the problem of channel clogging, because although the cross-sectional size is reduced, it is limited by the actual situation of structural processing and manufacturing. The width of the end of the general channel can only be reduced to about 300mm (for general urban sewage treatment plants), and the water flow speed at the end of the channel is 0, so the sludge in the water will still accumulate in the channel and need to be manually cleaned regularly. Moreover, since the channel adopts a variable cross-section setting, it brings great inconvenience to the design and installation, and increases the manufacturing cost. Summary of the invention

[0008] The present invention provides a secondary sedimentation tank water distribution trough with circumferential inlet and outlet, which is used to solve the defect of sludge accumulation in the water distribution trough in the prior art, and realizes that the water distribution trough itself can regularly clear the sludge in the water distribution channel, ensuring that the water distribution channel is always in a clean state, and basically avoiding the occurrence of siltation.

[0009] The present invention provides a peripheral inlet and outlet secondary sedimentation tank water distribution channel, comprising: a water distribution channel, the water distribution channel is arranged along the wall of the secondary sedimentation tank, and a plurality of water distribution pipes are arranged at the bottom;

[0010] an inlet channel, the inlet channel being in communication with the water distribution channel;

[0011] A flow control plate is arranged at the intersection of the water distribution channel and the water inlet channel, and one end of the flow control plate can be rotatably arranged on the inner wall of the water distribution channel away from the water inlet channel, and the other end can be docked at any position on the side wall or inside of the water inlet channel.

[0012] According to a circumferential inlet and outlet secondary sedimentation tank water distribution channel provided by the present invention, a rotating shaft is provided at one end of the flow control plate, and the rotating shaft is rotatably arranged on the side wall of the water distribution channel.

[0013] According to a peripheral inlet and outlet secondary sedimentation tank water distribution trough provided by the present invention, one end of the flow control plate close to the water inlet channel is located on the side wall of the water inlet channel so that the incoming water flows clockwise.

[0014] According to a peripheral inlet and outlet secondary sedimentation tank water distribution trough provided by the present invention, one end of the flow control plate close to the water inlet channel is located on the side wall of the water inlet channel so that the incoming water flows counterclockwise.

[0015] According to a peripheral inlet and outlet secondary sedimentation tank water distribution trough provided by the present invention, one end of the flow control plate close to the water inlet channel is located in the middle of the water inlet channel to split the incoming water into two paths.

[0016] According to the peripheral inlet and outlet secondary sedimentation tank water distribution trough provided by the present invention, the flow control plate is controlled manually or automatically.

[0017] According to the peripheral inlet and outlet secondary sedimentation tank water distribution trough provided by the present invention, the water distribution pipes are evenly distributed.

[0018] According to a peripheral inlet and outlet secondary sedimentation tank water distribution channel provided by the present invention, the cross-sectional length of the flow control plate is greater than the width of the water distribution channel, and the height is not less than the height of the water distribution channel.

[0019] According to a peripheral inlet and outlet secondary sedimentation tank water distribution trough provided by the present invention, the flow control plate is made of stainless steel.

[0020] The present invention also provides a secondary sedimentation tank, comprising: the above-mentioned circumferential inlet and outlet secondary sedimentation tank water distribution tank.

[0021] The present invention also provides a method for distributing water in a secondary sedimentation tank with a circular inlet and outlet, which utilizes the secondary sedimentation tank and includes the following steps: switching the flow direction of the inlet water flow by changing the position of the flow control plate, so as to regularly clean the channel siltation by the power of the water flow.

[0022] The peripheral inlet and outlet secondary sedimentation tank water distribution trough and secondary sedimentation tank provided by the present invention have a partition wall between the head end and the end of the water distribution channel made into a movable baffle through the arrangement of a flow control plate, one end of the flow control plate is connected to the inner wall of the water distribution channel away from the water inlet channel, and the other end is located at any position on the side wall or inside of the water inlet channel. The position of the flow control plate is switched regularly, and the silt in the water distribution channel is regularly cleared by the inlet water flow, thereby ensuring that the water distribution channel is always in a clean state, and the occurrence of siltation can be basically avoided. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0024] Figure 1 is a top view of Example 1 provided by the present invention;

[0025] Figure 2 It is an enlarged view of point A in Example 1 provided by the present invention;

[0026] Figure 3 is a top view of Example 2 provided by the present invention;

[0027] Figure 4 It is an enlarged view of point B in Example 2 provided by the present invention;

[0028] Figure 5 is a top view of Example 3 provided by the present invention;

[0029] Figure 6 It is an enlarged view of point C in Example 3 provided by the present invention;

[0030] Reference numerals:

[0031] 1: Inlet channel; 2: Distribution channel; 3: Flow control plate;

[0032] 4: Rotating shaft; 5: Water distribution pipe. DETAILED DESCRIPTION

[0033] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] like Figure 1-2 As shown, the peripheral inlet and outlet secondary sedimentation tank water distribution trough disclosed in Example 1 of the present invention includes a water distribution channel 2, an inlet channel 1 and a flow control plate 3. The water distribution channel 2 is arranged along the wall of the secondary sedimentation tank, and a plurality of water distribution pipes 5 are arranged at the bottom; the inlet channel 1 is connected with the water distribution channel 2, and is used to provide water to the water distribution channel 2. The flow control plate 3 is arranged at the intersection of the water distribution channel 2 and the inlet channel 1, and one end of the flow control plate is rotatably arranged on the side wall of the water distribution channel 2 away from the inlet channel 1, and the other end is located on the side wall of the inlet channel 1, so that the incoming water flows clockwise.

[0035] The working process of the embodiment 1 of the present invention is that when the incoming water flows clockwise and flows along the water distribution channel 2 for one circle, the head end of the water distribution channel 2 is named as the a side of the flow control plate, and the end of the water distribution channel 2 is named as the b side of the flow control plate 3. In this embodiment, after the incoming water runs clockwise for a period of time, the water flow velocity in the first half of the water distribution channel 2 is faster, and the water flow velocity in the second half is slower, and even the flow velocity in the second half is lower than the non-silting flow velocity of the water flow, a large amount of active sludge in the mixed liquid of the aeration tank will be deposited in the second half of the channel, and sludge siltation will appear at the end of the water distribution channel 2, that is, near the b side of the flow control plate.

[0036] The water distribution pipes 5 are evenly distributed to make the water distribution more uniform.

[0037] Furthermore, a rotating shaft 4 is provided at one end of the flow control plate 3, and the rotating shaft 4 is rotatably provided on the side wall of the water distribution channel 2. One end of the flow control plate 3 rotates around the rotating shaft 4, so that the flow control plate 3 can be stopped at multiple positions, thereby adjusting the flow direction of the incoming water. The flow control plate 3 can be manually controlled or mechanically automatically controlled to achieve timed switching of the flow direction.

[0038] It should be noted that the rotating shaft 4 can be set in any structure as long as the flow control plate 3 can be adjusted to achieve position switching.

[0039] like Figure 3-4 As shown, the peripheral inlet and outlet secondary sedimentation tank water distribution trough disclosed in Example 2 of the present invention includes a water distribution channel 2, an inlet channel 1 and a flow control plate 3. The water distribution channel 2 is arranged along the wall of the secondary sedimentation tank, and a plurality of water distribution pipes 5 are arranged at the bottom. The inlet channel 1 is connected with the water distribution channel 2 to provide water to the water distribution channel 2. The flow control plate 3 is arranged at the intersection of the water distribution channel 2 and the inlet channel 1, and one end is rotatably arranged on the side wall of the water distribution channel 2 away from the inlet channel 1, and the other end is located on the side wall of the inlet channel 1 so that the incoming water flows counterclockwise.

[0040] The working process of Example 2 of the present invention is that when the incoming water flows counterclockwise and flows along the water distribution channel 2 for one circle, that is, the head end of the water distribution channel 2 is the b side of the flow control plate 3, and the end end is the a side of the flow control plate 3. After running for a period of time, sludge accumulation will appear at the end of the water distribution channel 2, that is, the a side of the flow control plate 3, and the sludge accumulation on the b side of the flow control plate in the previous Example 1 will be cleared at the larger water distribution flow rate of this embodiment.

[0041] During use, the switching between Embodiment 1 and Embodiment 2 can be realized regularly. Embodiment 1 and Embodiment 2 of the present invention take measures of switching the flow direction regularly, which can effectively prevent channel clogging, ensure the operation effect, and effectively reduce manual maintenance.

[0042] It should be noted that according to the technical requirements of designers or operators, such as Figure 5-6As shown, in embodiment 3 of the present invention, the flow control plate 3 can also be arranged in the middle or other position of the outlet of the water inlet channel 1 to adjust the water flow distribution on both sides of the water inlet of the water distribution channel 2, and water can enter through the a side and the b side of the flow control plate at the same time.

[0043] In addition, during the sludge accumulation period in the above embodiments, the parking position of the flow control plate 3 can be changed manually or automatically by machinery, so that the channel sludge can be cleared regularly, ensuring that the channel is always in a clean state and basically avoiding the occurrence of sludge.

[0044] Furthermore, the embodiments of the present invention all adopt water distribution channels with equal cross-sections, which greatly reduces the difficulty of work for designers or operators.

[0045] Another aspect of the present invention discloses a secondary sedimentation tank, comprising the above-mentioned peripheral inlet and outlet secondary sedimentation tank water distribution tank.

[0046] Another embodiment of the present invention discloses a method for distributing water in a secondary sedimentation tank with a circumferential inlet and outlet, comprising the following steps: switching the flow direction of the gold and water flow by changing the position of a flow control plate, so as to regularly clean the channel siltation by the power of the water flow.

[0047] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A secondary sedimentation tank with a circumferential inlet and outlet water distribution tank, characterized in that: include: A water distribution channel, which is arranged along the wall of the secondary sedimentation tank and has a plurality of water distribution pipes at the bottom; an inlet channel, the inlet channel being in communication with the water distribution channel; A flow control plate, wherein the flow control plate is arranged at the intersection of the water distribution channel and the water inlet channel, and one end of the flow control plate is rotatably arranged on the inner side wall of the water distribution channel away from the water inlet channel, and the other end is located at any position on the side wall or inside of the water inlet channel, and one end of the flow control plate is provided with a rotating shaft, and the rotating shaft is rotatably arranged on the side wall of the water distribution channel; the rotating shaft is rotated regularly to switch the flow control plate between a first working state, a second working state and a third working state, wherein, in the first working state, one end of the flow control plate close to the water inlet channel is located on the side wall of the water inlet channel, so that the incoming water flows clockwise; In the second working state, one end of the flow control plate close to the water inlet channel is located on the side wall of the water inlet channel so that the incoming water flows counterclockwise; in the third working state, one end of the flow control plate close to the water inlet channel is located in the middle of the interior of the water inlet channel so that the incoming water is divided into two paths.

2. The peripheral inlet and outlet secondary sedimentation tank water distribution tank according to claim 1 is characterized in that: The flow control plate is controlled manually or automatically.

3. The peripheral inlet and outlet secondary sedimentation tank water distribution tank according to claim 1 is characterized in that: The plurality of water distribution pipes are evenly distributed.

4. The peripheral inlet and outlet secondary sedimentation tank water distribution tank according to claim 1 is characterized in that: The cross-sectional length of the flow control plate is greater than the width of the water distribution channel, and the height is not less than the height of the water distribution channel.

5. A secondary sedimentation tank, characterized in that: It comprises the secondary sedimentation tank water distribution trough with peripheral inlet and outlet as described in any one of claims 1-4.

6. A method for distributing water in a secondary sedimentation tank with a circular inlet and outlet, using the secondary sedimentation tank of claim 5, comprising the following steps: The flow direction of the incoming water flow is switched by changing the position of the flow control plate, so that the channel siltation can be cleaned regularly by the power of the water flow.

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