Primary sedimentation tank for municipal sewage treatment

Abstract

A primary sedimentation tank for municipal sewage treatment comprises a tank body, a slag scraping device and a mud scraping device, the tank body is provided with an overflow weir, and hooks and clamping rollers are arranged on the upper edge of the tank body; the slag scraping device comprises an annular hose and a winder, one end of the hose is hung on the hook, the other end of the hose is wound on the winder, and the suspended part is clamped between the pair of clamping rollers; during slag scraping, the hose is inflated, so that the hose floats on the surface of the sewage, and meanwhile, the winder starts to unwind, so that the hose expands towards the circumferential direction of the tank body, and an oil layer and scum floating on the surface of the sewage are discharged into the overflow weir; the sludge scraping device comprises a rotating frame, a water inlet pipe and a sludge pumping pipe are arranged on the rotating frame in the radial direction, a water outlet of the water inlet pipe is arranged in the tangential direction of the tank body, and the rotating frame can be pushed to rotate through counter-acting force when the water inlet pipe discharges water. The slag scraping device and the mud scraping device can work intermittently, and have the characteristics of ingenious structure, high working efficiency and low energy consumption, and the construction cost and the operation cost of the primary sedimentation tank are greatly reduced.

Description

Technical Field

[0001] The invention relates to the technical field of sewage treatment, in particular to a primary sedimentation tank for municipal sewage treatment. Background Art

[0002] After municipal sewage enters the sewage treatment plant, it must first be screened for slag removal and sediment separation, and then enter the primary sedimentation tank for sedimentation treatment, so that the suspended matter in the sewage is settled at the bottom of the primary sedimentation tank. The existing primary sedimentation tank is circular, and the diameter is usually more than 12 meters. A slag scraper and a mud scraper are set in the primary sedimentation tank. The function of the slag scraper is to scrape off the oil layer and scum floating on the surface of the sewage, and the function of the mud scraper is to scrape off the sludge settled at the bottom of the primary sedimentation tank. The structure and working principle of the slag scraper and the mud scraper can be referred to the patent with application number 201721492677.7.

[0003] The existing primary sedimentation tank has the following problems: 1. The scraper and sludge scraper rotate around the center of the primary sedimentation tank, which requires the installation of a central pillar, a circular track, a working bridge, and a high-power drive mechanism, resulting in a high construction cost for the primary sedimentation tank; 2. The removal efficiency of the scraper and mud scraper is very low, and the drive motor needs to run continuously, resulting in huge annual power consumption, which greatly increases the operating cost of the primary sedimentation tank. Summary of the invention

[0004] In order to overcome the shortcomings of the background technology, the present invention discloses a primary sedimentation tank for municipal sewage treatment, the purpose of which is: 1. Reduce the construction cost of primary sedimentation tanks; 2. Improve scraping efficiency and dredging efficiency, and reduce the operating cost of the primary sedimentation tank.

[0005] In order to achieve the above-mentioned invention object, the present invention adopts the following technical scheme: A primary sedimentation tank for municipal sewage treatment, comprising: The tank body is circular and has an overflow weir. A hook and a pair of clamping rollers are provided on the upper edge of the tank body. The hook and the pair of clamping rollers are arranged opposite to each other along the diameter direction of the tank body. The scraping device includes a reel and an annular hose. One end of the hose is hung on a hook, and the other end is wound on the reel. The suspended part is clamped between a pair of clamping rollers. An air nozzle is installed on the hose. When scraping the residue, air is inflated into the hose through the air nozzle to make the hose float on the surface of the sewage. At the same time, the reel starts to unwind, so that the hose expands in the circumferential direction of the tank body, and the oil layer and scum floating on the surface of the sewage are discharged into the overflow weir. The sludge scraping device comprises a rotating frame arranged at the center of the pool body, a water inlet pipe and a sludge suction pipe are radially arranged on the rotating frame, the sludge suction pipe is close to the bottom of the pool body, and the water inlet pipe is located above the sludge suction pipe; the sludge suction pipe has a scraper plate and a sludge suction port for removing sludge deposited at the bottom of the pool body; the water outlet of the water inlet pipe is arranged along the tangent direction of the pool body, and the rotating frame and the sludge suction pipe can be driven to rotate by the reaction force when the water inlet pipe discharges water.

[0006] To further improve the technical solution, the pool body has a water outlet pipe, the water outlet pipe is located above the water inlet pipe, and the water inlet of the water outlet pipe is close to the center of the pool body.

[0007] To further improve the technical solution, the bottom of the pool body is conical, a sink is provided at the tip of the cone, a mud discharge pipe is provided in the sink, and the mud discharge pipe is connected to an external mud discharge pump.

[0008] To further improve the technical solution, the rotating frame is arranged in the caisson, and the rotating frame includes a vertical pipe and a water jacket wrapped around the outside of the vertical pipe, the water inlet pipe is connected to the upper end of the vertical pipe, the outlet of the mud suction pipe is connected to the water jacket, and a bearing is arranged between the water jacket and the caisson; a rotating joint is connected to the lower ends of the vertical pipe and the water jacket, the water inlet pipe is connected to an external water inlet pump through the vertical pipe and the rotating joint, and the mud suction pipe is connected to an external mud suction pump through the water jacket and the rotating joint.

[0009] To further improve the technical solution, a roller that can roll on the bottom of the pool body is arranged on the mud pumping pipe, and a support rod is connected between the mud pumping pipe and the water inlet pipe.

[0010] To further improve the technical solution, there are two water inlet pipes and two mud extraction pipes, and the two water inlet pipes and the two mud extraction pipes are symmetrically arranged about the center of the pool body.

[0011] To further improve the technical solution, the reel is composed of a reel driven by a motor.

[0012] After implementing the above technical solution, the beneficial effects produced by the present invention are: 1. Compared with the traditional rotary scraper, this scraper does not need to set up a long and complex rotating part and slag removal mechanism. The oil layer and scum on the surface of the sewage can be completely scraped off by only one inflation expansion of the hose.

[0013] 2. The existing scraper device only has the functions of scraping and shoveling mud, but not the function of pumping mud. Only a part of the shoveled mud slides into the sink along the conical surface and then is discharged through the mud discharge pipe, so the scraper device needs to rotate continuously. The scraper device not only has the functions of scraping and shoveling mud, but also has the function of pumping mud. Moreover, the mud pumping pipe can rotate only by the reaction force of the incoming water, and at least half a circle is needed to discharge all the sludge.

[0014] 3. Since the scraping device and the mud scraping device of the present invention have very high scraping efficiency and silt clearing efficiency, they can work intermittently, greatly reducing the consumption of electric energy.

[0015] 4. This primary sedimentation tank has the characteristics of ingenious structure, high working efficiency and low energy consumption, which greatly reduces the construction cost and operation cost of the primary sedimentation tank. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Attached Figure 1 Shown is a schematic diagram of the overall structure of a primary sedimentation tank for municipal sewage treatment.

[0017] Attached Figure 2 Shown is a schematic diagram of the structure of the pool body.

[0018] Attached Figure 3 The attached Figure 2 A local enlarged view of point P in the middle.

[0019] Attached Figure 4 The attached Figure 2 Top view of the .

[0020] Attached Figure 5 The attached Figure 4 A partial enlarged view of the middle Q.

[0021] Attached Figure 6 The attached Figure 4 A partial enlarged view of the R in the middle.

[0022] Attached Figure 7 The attached Figure 1 Sectional view of AA.

[0023] Attached Figure 8 The attached Figure 7 A local enlarged view of the S in the middle.

[0024] Attached Fig. 9 The attached Figure 7 A partial enlarged view of the T in the middle.

[0025] Attached Fig.10 Shown is a schematic diagram of the hose beginning to expand.

[0026] Attached Fig.11 The attached Fig.10 Cross-sectional view of CC.

[0027] Attached Fig.12 Shown is a schematic diagram of the hose after expansion.

[0028] Attached Fig.13 The attached Fig.12 Cross-sectional view of DD.

[0029] Attached Fig.14 Shown is a structural schematic diagram of a scraping device.

[0030] Attached Fig.15 Another structural schematic diagram of a scraping device is shown.

[0031] Attached Fig.16 The attached Figure 1 Top view of the .

[0032] Attached Fig.17 The attached Figure 1 Cross-sectional view of BB. Attached photos

[0033] 10. Tank body; 11. Overflow weir; 12. Outlet pipe; 13. Sink; 14. Mud discharge pipe; 15. Mud discharge pump; 16. Hook; 17. Clamp roller; 20. Slag scraping device; 21. Hose; 22. Air nozzle; 23. Winding reel; 24. Motor; 25. Oil layer and slag; 30. Mud scraping device; 31. Rotating frame; 311. Vertical pipe; 312. Water jacket; 313. Bearing; 314. Rotary joint; 32. Water inlet pipe; 321. Tangential elbow; 33. Mud suction pipe; 331. Mud suction port; 332. Mud scraping plate; 333. Roller; 34. Support rod; 35. Mud suction pump; 36. Water inlet pump. DETAILED DESCRIPTION

[0034] The preferred embodiments of the present invention are described below with reference to the accompanying drawings. It should be understood by those skilled in the art that these embodiments are only used to explain the technical principles of the present invention and are not intended to limit the scope of protection of the present invention. It should be noted that in the description of the present invention, the terms "front", "rear", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside" and the like indicating directions or positional relationships are based on the directions or positional relationships shown in the accompanying drawings, which are only for the convenience of description, and do not indicate or imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention. It should also be noted that in the description of the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, or the internal connection of two elements. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0035] Refer to the attached Figure 1 , attached Figure 1The figure shows a schematic diagram of the overall structure of a primary sedimentation tank for municipal sewage treatment. Like the existing primary sedimentation tank, the primary sedimentation tank has a circular tank body 10, in which a scraper device 20 and a mud scraper device 30 are arranged. The structure and function thereof are described in detail below.

[0036] Refer to the attached Figure 2-6 . Figure 2-6 It can be seen that, like the existing primary sedimentation tank, an overflow weir 11 is provided outside the tank body 10, the bottom of the tank body 10 is conical, a sink 13 is provided at the tip of the cone, a sludge discharge pipe 14 is provided inside the sink 13, and the sludge discharge pipe 14 is connected to an external sludge discharge pump 15 for discharging the sludge inside the sink 13. The difference is that the tank body 10 has an outlet pipe 12, which is located at the upper part of the tank body 10, close to the water surface, and the water inlet of the outlet pipe 12 is close to the center of the tank body 10, which is the static zone of the sewage. A hook 16 and a pair of clamping rollers 17 are provided on the upper edge of the tank body 10, and the hook 16 and the pair of clamping rollers 17 are arranged opposite to each other along the diameter direction of the tank body 10.

[0037] Refer to the attached Figure 7-9 . Figure 8-10 It can be seen that the scraper device 20 includes a reel and an annular hose 21, one end of the hose 21 is hung on the hook 16, the other end is wound on the reel, and the suspended part is clamped between a pair of clamping rollers 17. The material of the hose 21 can be soft and elastic natural rubber or butyl rubber, and butyl rubber is usually used for inner tubes. The reel can be a conventional spring reel, or a reel driven by a motor. In this embodiment, the reel is composed of a reel 23 driven by a motor 24, and the hose 21 is wound on the reel 23.

[0038] Refer to the attached Figure 3-6 An air nozzle 22 is installed at one end of the hose 21 located at the hook 16. When scraping is not needed, the hose 21 is in a deflated state. Under the action of the reel, the hose 21 is tightened between the hook 16 and the reel 23, and the suspended part is clamped between a pair of clamping rollers 17. The pair of clamping rollers 17 is used to clamp the hose 21 and squeeze out the air remaining in the hose 21, so that the hose 21 is wound on the reel 23 in an airless state.

[0039] Refer to the attached Figure 10-13 When scraping the slag, the hose 21 is inflated through the air nozzle 22. Since the clamping roller 17 has a clamping effect on the hose 21, the hose 21 located above the sewage surface begins to expand, detaches from the hook 16 and floats on the surface of the sewage. At the same time, the motor 24 reverses to drive the reel to unwind. Under the action of the inflation pressure, the hose 21 wound on the reel 23 is pulled into the tank body 10 more and more, and expands in the circumferential direction of the tank body 10 after inflation, and the oil layer and scum 25 floating on the sewage surface are all discharged into the overflow weir 11.

[0040] After scraping, the air nozzle 22 is opened to release air, and the motor 24 rotates forward at the same time, driving the reel to reel the hose 21, so that the hose 21 is in a suspended and taut state again. Since the oil layer and scum 25 on the surface of the sewage can be scraped off by one inflation and expansion of the hose 21, the efficiency is very high. Therefore, the scraping device 20 works at intervals, generally scraping once every 2-4 hours.

[0041] From the above, it can be seen that, unlike the traditional rotary scraper, the scraper device 20 does not need to be equipped with a very long and complex rotating part and slag removal mechanism. The oil layer and scum 25 on the entire sewage surface can be completely scraped off through only one inflation expansion of the hose 21, which not only greatly improves the scraping efficiency but also reduces the consumption of electric energy.

[0042] Refer to the attached Figure 1 and attached Fig.14 The scraper device 30 includes a rotating frame 31 disposed at the center of the tank body 10, and the rotating frame 31 is installed in the sink 13. A water inlet pipe 32 and a mud suction pipe 33 are radially arranged on the rotating frame 31. The mud suction pipe 33 is close to the bottom of the tank body 10, and the water inlet pipe 32 is located above the mud suction pipe 33, but lower than the height of the water outlet pipe 12. A plurality of support rods 34 are connected between the mud suction pipe 33 and the water inlet pipe 32, and the support rods 34, the mud suction pipe 33, and the water inlet pipe 32 form a stable truss structure.

[0043] The rotating frame 31 includes a vertical pipe 311 and a water jacket 312 wrapped around the outside of the vertical pipe 311. The water inlet pipe 32 is connected to the upper end of the vertical pipe 311. The outlet of the mud pumping pipe 33 is connected to the water jacket 312. A bearing 313 is provided between the water jacket 312 and the sink 13. A rotary joint 314 is connected to the lower ends of the vertical pipe 311 and the water jacket 312. The water inlet pipe 32 is connected to an external water inlet pump 36 through the vertical pipe 311 and the rotary joint 314. The mud pumping pipe 33 is connected to an external mud pump 35 through the water jacket 312 and the rotary joint 314. The rotary joint 314 is an existing product, and its function is to realize that liquid enters the fixed pipe from the rotating pipe without leakage, or enters the rotating pipe from the fixed pipe.

[0044] Refer to the attached Fig.15 In order to balance the force and improve the scraping efficiency, two water inlet pipes 32 and two mud suction pipes 33 can be provided on the rotating frame 31, and the two water inlet pipes 32 and the two mud suction pipes 33 are symmetrically arranged about the center of the pool body 10. This embodiment adopts such a symmetrical structure.

[0045] Refer to the attached Fig.16. A tangential elbow 321 is provided at the water outlet end of the water inlet pipe 32, and the water outlet direction of the tangential elbow 321 is perpendicular to the water inlet pipe 32 and is arranged along the tangent of the pool body 10. When the tangential elbow 321 discharges water, a tangential water flow is generated, which can drive the rotating frame 31 and the mud extraction pipe 33 to rotate through the reaction force. Whether the rotating frame 31 can rotate and the rotation speed of the rotating frame 31 depend on the rotation speed of the water inlet pump 36. When it is not necessary to scrape mud, the rotation speed of the water inlet pump 36 is reduced, and the water inlet pipe 32 is normally supplied with water. At this time, the rotating frame 31 and the mud extraction pipe 33 do not rotate; when it is necessary to scrape mud, the rotation speed of the water inlet pump 36 is increased, so that the water outlet flow rate of the tangential elbow 321 is higher and the thrust is greater, so as to drive the rotating frame 31 and the mud extraction pipe 33 to rotate. Since the water surface is large and the circulation direction of the water outflowing from the water inlet pipe 32 is close to the pool wall, even if the flow rate increases, it will not affect the static state of the water in the central area of ​​the pool body 10, so the cleanliness of the water outflowing from the water outlet pipe 12 can be guaranteed.

[0046] Refer to the attached Fig.17 The mud pumping pipe 33 has a mud scraper 332 and a mud pumping port 331. The mud scraper 332 is welded to the outside of the mud pumping pipe 33 along the axial direction. The function of the mud scraper 332 is to shovel up the sludge deposited at the bottom of the tank body 10. The mud pumping port 331 is a strip-shaped port opened along the axial direction on the mud pumping pipe 33. The function of the mud pumping port 331 is to use negative pressure to suck the shoveled sludge into the mud pumping pipe 33, and then discharge the sludge from the primary sedimentation tank through the water jacket 312, the rotary joint 314, and the mud pump 35. In addition, two sets of rollers 333 are provided on the mud pumping pipe 33. The rollers 333 can roll on the bottom of the tank body 10, which can improve the stress state of the rotating frame 31 and the truss structure.

[0047] The existing scraper device only has the functions of scraping and shoveling mud, but not the function of pumping mud. Only a part of the shoveled mud slides into the sink 13 along the conical surface, and then is discharged through the mud discharge pipe 14, so the scraper device needs to rotate continuously. The mud pumping pipe 33 of the scraper device 30 not only has the functions of scraping and shoveling mud, but also has the function of pumping mud. The mud can be pumped out without scraping the mud into the sink 13. What is more clever is that the mud pumping pipe 33 does not need to be driven by external force, but can be rotated only by the reaction force of the incoming water. The mud pumping pipe 33 only needs to rotate half a circle at least to pump out all the sludge. Therefore, the scraper device 30 also works at intervals. Usually, only the water inlet pump 36 pumps water at a low speed to maintain the balance of water in and out of the pool body. Then, the speed of the water inlet pump 36 is increased every 2-3 hours to drive the mud pumping pipe 33 to rotate half a circle or a circle. At the same time, the mud pumping pump 35 and the mud discharge pump 15 are turned on to discharge sewage. The sludge at the bottom of the pool can be completely removed in about 20 minutes. Obviously, this mode of operation not only greatly improves the mud removal efficiency, but also reduces the consumption of electricity.

[0048] Depending on the specific situation, the slag scraping device 20 and the mud scraping device 30 can operate in coordination or independently.

[0049] Although the embodiments of the present invention have been shown and described, it is understood by those skilled in the art that various changes, modifications, substitutions and variations may be made to these embodiments without departing from the principles and spirit of the present invention, and the protection scope of the present invention is defined by the attached claims and their equivalents.

Claims

1. A primary sedimentation tank for municipal sewage treatment, characterized in that: include: The tank body is circular and has an overflow weir. A hook and a pair of clamping rollers are provided on the upper edge of the tank body. The hook and the pair of clamping rollers are arranged opposite to each other along the diameter direction of the tank body. The scraping device includes a reel and an annular hose. One end of the hose is hung on a hook, and the other end is wound on the reel. The suspended part is clamped between a pair of clamping rollers. An air nozzle is installed on the hose. When scraping the residue, air is inflated into the hose through the air nozzle to make the hose float on the surface of the sewage. At the same time, the reel starts to unwind, so that the hose expands in the circumferential direction of the tank body, and the oil layer and scum floating on the surface of the sewage are discharged into the overflow weir. The sludge scraping device comprises a rotating frame arranged at the center of the pool body, a water inlet pipe and a sludge suction pipe are radially arranged on the rotating frame, the sludge suction pipe is close to the bottom of the pool body, and the water inlet pipe is located above the sludge suction pipe; the sludge suction pipe has a scraper plate and a sludge suction port for removing sludge deposited at the bottom of the pool body; the water outlet of the water inlet pipe is arranged along the tangent direction of the pool body, and the rotating frame and the sludge suction pipe can be driven to rotate by the reaction force when the water inlet pipe discharges water.

2. A primary sedimentation tank for municipal sewage treatment as claimed in claim 1, characterized in that: The pool body is provided with a water outlet pipe, which is located above the water inlet pipe, and the water inlet of the water outlet pipe is close to the central part of the pool body.

3. A primary sedimentation tank for municipal sewage treatment as claimed in claim 1, characterized in that: The bottom of the pool body is conical, and a sinking platform is arranged at the tip of the cone. A mud discharge pipe is arranged in the sinking platform, and the mud discharge pipe is connected to an external mud discharge pump.

4. A primary sedimentation tank for municipal sewage treatment as claimed in claim 3, characterized in that: The rotating frame is arranged in the sinking platform, and the rotating frame includes a vertical pipe and a water jacket wrapped around the outside of the vertical pipe, the water inlet pipe is connected to the upper end of the vertical pipe, the outlet of the mud pumping pipe is connected to the water jacket, and a bearing is arranged between the water jacket and the sinking platform; a rotating joint is connected to the lower ends of the vertical pipe and the water jacket, the water inlet pipe is connected to an external water inlet pump through the vertical pipe and the rotating joint, and the mud pumping pipe is connected to an external mud pump through the water jacket and the rotating joint.

5. A primary sedimentation tank for municipal sewage treatment as claimed in claim 1, characterized in that: A roller which can roll on the bottom of the pool body is arranged on the mud pumping pipe, and a supporting rod is connected between the mud pumping pipe and the water inlet pipe.

6. A primary sedimentation tank for municipal sewage treatment as claimed in claim 1 or 5, characterized in that: There are two water inlet pipes and two mud suction pipes respectively, and the two water inlet pipes and the two mud suction pipes are symmetrically arranged about the center of the pool body.

7. A primary sedimentation tank for municipal sewage treatment as claimed in claim 1, characterized in that: The reel is composed of a reel driven by a motor.

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