Scum skimming device and scum skimming method for secondary sedimentation tank

Abstract

The invention discloses a scum skimming device and a scum skimming method for a secondary sedimentation tank. The scum skimming device comprises a coaxial fixed shaft fixed in a scum discharge pipe, and the coaxial fixed shaft is rotatably connected with an arc-shaped water baffle; a power device drives a driven wheel on the power device to push the water baffle to rise and fall slowly and quickly. The driven wheel is provided with a missing part, and when the missing part rotates to the position corresponding to the water baffle, the water baffle rapidly falls down due to gravity to form hydraulic jump, and dross is carried into the dross discharging pipe. The fixing shaft is connected with the water baffle through the connecting cylinder and the connecting rod, and the scrapers spirally arranged on the connecting cylinder synchronously clean moss on the inner wall of the slag discharging pipe. The working states of the driven wheel and the adjusting wheel can be switched by axially moving the rotating shaft, and different working condition requirements are met in cooperation with a crank or a motor. The device is compact in structure and high in deslagging efficiency, and the manual maintenance cost is remarkably reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of sewage treatment equipment, and in particular to a scum skimming device and a scum skimming method for a secondary sedimentation tank. Background Art

[0002] In the wastewater treatment process, the secondary sedimentation tank (SETC) is a key component, separating activated sludge from treated water. During this process, a large amount of scum accumulates on the surface of the SETC, including grease, foam, and suspended impurities. Existing treatment methods typically utilize a scraper installed in the SETC to slowly push the scum toward a skimmer, where it flows naturally into a discharge pipe, relying on the water level difference. However, this method has significant drawbacks: the scraper operates slowly, allowing scum to accumulate in the skimmer, preventing timely discharge. Over time, scum accumulates, even leading to blockage of the discharge port, requiring frequent manual cleaning, increasing operational costs and labor intensity. Furthermore, after long-term operation, moss easily grows on the inner walls of the discharge pipe, further compromising discharge efficiency. Therefore, an efficient and reliable SETC skimming device and method are urgently needed to address these existing issues. Summary of the Invention

[0003] In response to the shortcomings of the existing technology, the present invention provides a secondary sedimentation tank scum skimming device and method, which can automatically and efficiently discharge scum from the secondary sedimentation tank surface, and also has the function of cleaning moss on the inner wall of the scum discharge pipe, thereby reducing manual intervention and improving sewage treatment efficiency. To achieve the above objectives, the present invention adopts the following technical solutions: A secondary sedimentation tank slag skimming device is used in conjunction with an existing slag discharge pipe for discharging slag. The slag discharge pipe is provided with slag discharge ports for discharging slag, and the slag discharge ports are arranged in parallel and at intervals, comprising: A fixed shaft is fixedly installed in the slag discharge pipe. The fixed shaft is coaxially arranged with the slag discharge pipe and is rotatably connected to an arc-shaped water baffle. The water baffle is arranged on the water side of the slag discharge pipe and is in contact with the outer wall of the slag discharge pipe. The water baffle is used to raise the water level of the water entering the slag discharge pipe; The rotating shaft is rotatably mounted on the outer wall of the slag discharge pipe and is connected to a power device for driving the rotating shaft to rotate. The rotating shaft is fixedly connected to driven wheels at intervals, and the driven wheels are used to push the water baffle to swing back and forth slowly up and down and quickly around the fixed axis.

[0004] Furthermore, the fixed shaft is rotatably connected to a spaced-apart connecting cylinder, the connecting cylinder is fixedly connected to a connecting rod, and the connecting rod passes through the slag discharge port and is fixedly connected to the water baffle.

[0005] Furthermore, a missing portion is provided on the driven wheel, and the arc length of the missing portion is sufficient to allow the water baffle to fall to the bottom of its stroke.

[0006] Furthermore, the driven wheel abuts against the outer wall of the water baffle, and drives the water baffle to rotate through friction.

[0007] Furthermore, the driven wheel is provided with a gear, and the outer wall of the water baffle is provided with a bar-shaped rack matched with the driven wheel.

[0008] Furthermore, the connecting cylinder is fixedly connected with an arc-shaped scraper, and the scraper is arranged in a spiral manner, with the arc direction facing away from the slag discharge port.

[0009] Furthermore, the rotating shaft is fixedly connected with adjusting wheels corresponding to the number of driven wheels and located on the same side, and two parallel grooves are provided on the water baffle. The groove setting has two states, state one: when the driven wheel cooperates with the water baffle, one of the grooves is located corresponding to the position of the adjusting wheel, that is, the adjusting wheel is disengaged from the water baffle; state two: move the rotating shaft to make the adjusting wheel cooperate with the water baffle, and the position of the other groove corresponds to the position of the driven wheel, that is, the driven wheel is disengaged from the water baffle.

[0010] Furthermore, a hexagonal blind hole is provided at the end of the rotating shaft, and the blind hole is equipped with a corresponding crank.

[0011] Furthermore, one end of the rotating shaft is fixedly connected to a ridge block, an outer sleeve of the ridge block is provided with a driving wheel in sliding connection, and the driving wheel is transmission-connected to a motor.

[0012] The present invention also provides a method for skimming scum in a secondary sedimentation tank, using the scum skimming device as described above, comprising the following steps: The power device is started to drive the rotating shaft to rotate. The driven wheel on the rotating shaft contacts the water baffle, and through friction or gear rack transmission, the water baffle is pushed to slowly rise around the fixed axis. The arc-shaped water baffle raises the water level on the water side of the slag discharge pipe, so that the slag on the surface of the secondary sedimentation tank is gathered in front of the water baffle; When the driven wheel rotates to the position corresponding to the missing part and the water baffle, the driven wheel and the water baffle are separated, and the water baffle falls rapidly under the action of gravity, forming a water jump effect, which quickly flushes the accumulated slag into the slag discharge pipe for discharge; During the rising and falling process of the water baffle, the spirally arranged scrapers on the connecting tube will clean the moss on the inner wall of the slag discharge pipe synchronously; When the moss is thick and needs to be cleaned deeply, the rotating shaft is moved axially to make the adjusting wheel cooperate with the water baffle and disengage the driven wheel. The adjusting wheel is rotated by the crank to drive the water baffle to rotate in a larger range, and the moss at the bottom of the slag discharge pipe is completely cleaned.

[0013] Compared with the prior art, the present invention has the following beneficial effects: 1. The driven wheel drives the water baffle to swing slowly up and quickly down, forming a "water jump" effect, allowing the slag to quickly enter the slag discharge pipe, significantly improving the slag discharge efficiency and solving the problems of slow slag discharge and slag accumulation in existing scrapers. 2. The spiral scraper on the connecting tube moves synchronously with the water baffle, automatically cleaning the moss on the inner wall of the slag discharge pipe during the slag discharge process, reducing manual maintenance; 3. By axially moving the rotating shaft, the working status of the driven wheel and the adjusting wheel can be switched, which can realize daily automatic slag discharge, or manual intervention when the moss is thick, and the adjusting wheel can be driven by the crank to achieve a wider range of cleaning; 4. It adopts mechanical transmission mode, with compact structure, stable operation and low maintenance cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The present invention will be further described below with reference to the accompanying drawings and examples: Figure 1 This is a schematic diagram of the main structure of an embodiment of the present invention; Figure 2 This is a schematic diagram of a working state of an embodiment of the present invention; Figure 3 This is a schematic diagram of the second working state of an embodiment of the present invention; Figure 4 This is a schematic diagram of the structure of the end portion of the rotating shaft according to an embodiment of the present invention.

[0015] In the above drawings: slag discharge pipe 1, slag discharge port 2, fixed shaft 3, rotating shaft 4, connecting tube 5, connecting rod 6, water baffle 7, motor 8, driven wheel 9, missing part 10, scraper 12, adjusting wheel 13, grooves 14, 15, blind hole 16, crank 17, edge block 18, driving wheel 19. DETAILED DESCRIPTION

[0016] The technical solution of the present invention is further described below with reference to the accompanying drawings and embodiments.

[0017] like Figures 1-3 As shown, the embodiment of the present invention provides a secondary sedimentation tank slag skimming device, which is used in conjunction with an existing slag discharge pipe 1. The slag discharge pipe 1 is provided with a plurality of slag discharge ports 2 arranged in parallel and spaced apart. The device includes a fixed shaft 3 and a rotating shaft 4.

[0018] A fixed shaft 3 is fixedly mounted within the slag discharge pipe 1, coaxially arranged therewith. A plurality of spaced connecting tubes 5 are rotatably connected to the fixed shaft 3. Connecting rods 6 are fixedly connected to the connecting tubes 5. These rods 6 pass through the slag discharge port 2 and are fixedly connected to a curved water baffle 7. The water baffle 7 is located on the water-facing side of the slag discharge pipe 1 and is in contact with the outer wall of the pipe 1.

[0019] The rotating shaft 4 is rotatably mounted on the outer wall of the slag discharge pipe 1. To resist sewage corrosion, duplex stainless steel can be used. It is connected to the motor 8 via a transmission method such as a belt or chain. The belt can be a neoprene synchronous belt, and the chain can be a 316L stainless steel roller chain, a duplex stainless steel chain, or an engineering plastic chain such as POM polyoxymethylene + carbon fiber reinforcement. The motor 8 serves as a power device to drive the rotating shaft 4. Driven wheels 9 are fixedly connected to the rotating shaft 4 at intervals. The driven wheels 9 are against the outer wall of the water retaining plate 7 and are used to drive the water retaining plate 7 to rotate about the fixed shaft 3. The driven wheels 9 can be made of reinforced engineering plastics such as POM polyoxymethylene + glass fiber reinforcement.

[0020] like Figure 1 As shown, a missing portion 10 is provided on the driven wheel 9. The arc length of the missing portion 10 is sufficient to allow the water baffle 7 to fall to the bottom of its travel under the action of gravity. There are two transmission modes between the driven wheel 9 and the water baffle 7: Friction drive: The outer circumference of the driven wheel 9 is in direct contact with the outer wall of the water baffle 7, and the water baffle 7 is driven to rotate by friction; Gear rack transmission: A gear is provided on the driven wheel 9, and a bar rack matching with the driven wheel 9 is provided on the outer wall of the water baffle 7.

[0021] The connecting tube 5 is fixedly connected to an arc-shaped scraper 12. The scraper 12 is arranged in a spiral shape, with the arc direction facing away from the slag discharge port 2. When water falls, the water flow hits the scraper 12, and the scraper 12 drives the water retaining plate 7 to fall rapidly, thereby increasing the height difference and effect of the water jump, facilitating the rapid water flow to carry away more slag, and improving the slag discharge effect. When the water retaining plate 7 rotates around the fixed axis 3, the scraper 12 moves synchronously with it, cleaning the inner wall of the slag discharge pipe 1.

[0022] The rotating shaft 4 is fixedly connected with an adjusting wheel 13 corresponding in number to the driven wheel 9 and located on the same side. The water baffle 7 is provided with two parallel grooves 14 and 15, and the grooves are arranged in two states: State 1 (daily slag discharge state): Figure 2 As shown, the driven wheel 9 cooperates with the water baffle 7, and the groove 14 is located at a position corresponding to the adjusting wheel 13, and the adjusting wheel 13 is disengaged from the water baffle 7; State 2 (deep cleaning state): Figure 3 As shown, the rotating shaft 4 is moved to make the adjusting wheel 13 cooperate with the water baffle 7, the position of the groove 15 corresponds to the position of the driven wheel 9, and the driven wheel 9 is separated from the water baffle 7.

[0023] The grooves 14 and 15 are both provided with bevels to facilitate the engagement or disengagement of the driven wheel 9 and the adjusting wheel 13 with the outer wall of the slag discharge pipe 1 .

[0024] like Figure 3As shown, the end of the rotating shaft 4 is provided with a hexagonal blind hole 16, which is equipped with a corresponding crank handle 17. A ridge 18 is fixedly connected to one end of the rotating shaft 4. Ridge 18 is fitted with a sliding drive pulley 19, which is connected to the motor 8 via a belt or chain. To switch operating modes, the rotating shaft 4 can be axially moved, allowing the drive pulley 19 to slide on the ridge 18 while maintaining power transmission.

[0025] Working principle: Daily slag discharge process: The motor 8 drives the rotating shaft 4 to rotate, and the driven wheel 9 rotates accordingly; The driven wheel 9 pushes the water baffle 7 to slowly rise around the fixed shaft 3 through friction or gear rack transmission. The water baffle 7 raises the water level on the water side of the slag discharge pipe 1, so that the slag gathers in front of the water baffle 7. When the missing portion 10 of the driven wheel 9 rotates to the position corresponding to the water baffle 7, the driven wheel 9 is out of contact with the water baffle 7, and the water baffle 7 falls rapidly under the action of gravity, forming an effect similar to a "water jump", so that the accumulated slag quickly enters the slag discharge pipe 1; The rotating shaft 4 continues to rotate, and the driven wheel 9 contacts the water baffle 7 again and pushes it up, and this cycle is repeated to achieve continuous slag discharge.

[0026] Moss cleaning process: During the rising and falling process of the water baffle 7, the spiral scraper 12 on the connecting tube 5 moves synchronously with the water baffle 7 to automatically clean the inner wall of the slag discharge pipe 1; When the moss is thick and the automatic cleaning effect is poor, the rotating shaft 4 is axially moved to the second state, at which time the adjusting wheel 13 is engaged with the water baffle 7 and the driven wheel 9 is disengaged from the water baffle 7; You can choose to turn off the motor 8 and use the crank 17 to manually rotate the rotating shaft 4, so that the adjusting wheel 13 drives the water baffle 7 to rotate in a larger range, thereby achieving comprehensive moss cleaning on the bottom of the slag discharge pipe 1.

[0027] The present invention also provides a method for skimming scum in a secondary sedimentation tank, using the scum skimming device described above, comprising the following steps: The power device is started to drive the rotating shaft 4 to rotate. The driven wheel 9 on the rotating shaft 4 contacts the water baffle 7. Through friction or gear rack transmission, the water baffle 7 is pushed to slowly rise around the fixed shaft 3. The arc-shaped water baffle 7 raises the water level on the water side of the slag discharge pipe 1, so that the slag on the surface of the secondary sedimentation tank is gathered in front of the water baffle 7. When the driven wheel 9 rotates to the position corresponding to the missing part 10 and the water baffle 7, the driven wheel 9 is separated from the water baffle 7, and the water baffle 7 falls rapidly under the action of gravity, forming a water jump effect, which quickly flushes the accumulated slag into the slag discharge pipe 1 for discharge; During the rising and falling process of the water baffle 7, the spirally arranged scrapers 12 on the connecting tube 5 simultaneously clean the moss on the inner wall of the slag discharge pipe 1; When the moss is thick and needs to be cleaned deeply, the rotating shaft 4 is moved axially to make the adjusting wheel 13 cooperate with the water baffle 7 and disengage the driven wheel 9. The adjusting wheel 13 is rotated by the crank 17 to drive the water baffle 7 to rotate in a larger range, so that the moss at the bottom of the slag discharge pipe 1 is completely cleaned.

Claims

1. A slag skimming device for a secondary sedimentation tank, used in conjunction with an existing slag discharge pipe for discharging slag, the slag discharge pipe is provided with slag discharge ports for discharging slag, and the slag discharge ports are arranged in parallel and at intervals, characterized in that: include: A fixed shaft is fixedly installed in the slag discharge pipe. The fixed shaft is coaxially arranged with the slag discharge pipe and is rotatably connected to an arc-shaped water baffle. The water baffle is arranged on the water side of the slag discharge pipe and is in contact with the outer wall of the slag discharge pipe. The water baffle is used to raise the water level of the water entering the slag discharge pipe; The rotating shaft is rotatably mounted on the outer wall of the slag discharge pipe and is connected to a power device for driving the rotating shaft to rotate. The rotating shaft is fixedly connected to driven wheels at intervals, and the driven wheels are used to push the water baffle to swing back and forth slowly up and down and quickly around the fixed axis.

2. A secondary sedimentation tank scum skimming device as claimed in claim 1, characterized in that: The fixed shaft is rotatably connected to a connecting cylinder that is spaced apart. The connecting cylinder is fixedly connected to a connecting rod that passes through a slag discharge port and is fixedly connected to a water baffle.

3. A secondary sedimentation tank scum skimming device as claimed in claim 2, characterized in that: A missing portion is provided on the driven wheel, and the arc length of the missing portion is sufficient to allow the water baffle to evenly fall to the bottom of its stroke.

4. A secondary sedimentation tank scum skimming device as claimed in claim 3, characterized in that: The driven wheel abuts against the outer wall of the water baffle, and drives the water baffle to rotate through friction.

5. A secondary sedimentation tank scum skimming device as claimed in claim 3, characterized in that: The driven wheel is provided with a gear, and the outer wall of the water baffle is provided with a bar-shaped rack matched with the driven wheel.

6. A secondary sedimentation tank scum skimming device as claimed in claim 4 or 5, characterized in that: The connecting cylinders are all fixedly connected with arc-shaped scrapers, which are arranged in a spiral manner with the arc direction facing away from the slag discharge port.

7. A secondary sedimentation tank scum skimming device as claimed in claim 7, characterized in that: The rotating shaft is fixedly connected with an adjusting wheel corresponding to the number of driven wheels and located on the same side. The water baffle is provided with two parallel grooves. The setting of the grooves has two states. State 1: when the driven wheel is engaged with the water baffle, one of the grooves is located corresponding to the position of the adjusting wheel, that is, the adjusting wheel is disengaged from the water baffle; State 2: Move the rotating shaft to make the adjusting wheel match with the water baffle, and the position of the other groove corresponds to the position of the driven wheel, that is, the driven wheel is disengaged from the water baffle.

8. A secondary sedimentation tank scum skimming device as claimed in claim 7, characterized in that: The end of the rotating shaft is provided with a hexagonal blind hole, and the blind hole is equipped with a crank corresponding thereto.

9. A secondary sedimentation tank scum skimming device as claimed in claim 8, characterized in that: One end of the rotating shaft is fixedly connected with an edge block, and an outer sleeve of the edge block is provided with a driving wheel in sliding connection, and the driving wheel is transmission-connected with a motor.

10. A method for skimming scum in a secondary sedimentation tank, characterized in that: Using the scum skimming device according to any one of claims 1 to 9 comprises the following steps: The power device is started to drive the rotating shaft to rotate. The driven wheel on the rotating shaft contacts the water baffle, and through friction or gear rack transmission, the water baffle is pushed to slowly rise around the fixed axis. The arc-shaped water baffle raises the water level on the water side of the slag discharge pipe, so that the slag on the surface of the secondary sedimentation tank is gathered in front of the water baffle; When the driven wheel rotates to the position corresponding to the missing part and the water baffle, the driven wheel and the water baffle are separated, and the water baffle falls rapidly under the action of gravity, forming a water jump effect, which quickly flushes the accumulated slag into the slag discharge pipe for discharge; During the rising and falling process of the water baffle, the spirally arranged scrapers on the connecting tube will clean the moss on the inner wall of the slag discharge pipe synchronously; When the moss is thick and needs to be cleaned deeply, the rotating shaft is moved axially to make the adjusting wheel cooperate with the water baffle and disengage the driven wheel. The adjusting wheel is rotated by the crank to drive the water baffle to rotate in a larger range, and the moss at the bottom of the slag discharge pipe is completely cleaned.

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