An alternating vertical filtration overflow water intake type sedimentation tank

Abstract

The present invention belongs to the technical field of hydraulic structure design of water conservancy and hydropower engineering, and specifically relates to an alternating vertical filtering overflow water intake type sedimentation tank. The first diffusion section, the primary sedimentation tank, the overflow section, the second diffusion section and the secondary sedimentation tank are arranged in sequence according to the water flow direction; the first sluice and the water diversion channel are obliquely intersected at 30° to 60°, and water is diverted obliquely; the water in the primary sedimentation tank flows through the water gushing holes on a section of the rectifying plate into the primary filter tank, and after being filtered by a section of the filter layer, it flows into the water collection port from a pair of overflow water channels, and overflows from the baffle wall at the water outlet end of the primary filter tank into the water collection port; the water in the secondary sedimentation tank flows through the water gushing holes on the second section of the rectifying plate into the secondary filter tank, and after being filtered by the second reverse filter layer, it overflows from the baffle wall at the water outlet end of the secondary filter tank into the water outlet, sediments downward, and water is taken upward; the above oblique water diversion and upward water intake method effectively filters large particles of sediment into the tank.

Description

Technical Field

[0001] The invention belongs to the technical field of hydraulic structure design of water conservancy and hydropower engineering, is suitable for water intake projects on channels with high sediment content, and specifically relates to an alternating vertical filtering overflow water intake type sedimentation tank. Background Art

[0002] The sedimentation tank is one of the important components of the water diversion project, and the sediment content at the outlet of the sedimentation tank is the most important factor in determining whether the water diversion project can operate normally.

[0003] Sedimentation tanks for water diversion projects usually adopt a single-chamber or multi-chamber layout. After the water entering the tank diffuses, the flow cross-section increases, the flow velocity decreases, and the hydraulic sediment-carrying force is reduced. Sediment in the water flow that is larger than the designed settling particle size can be settled, reducing the sediment content of the water outflowing the tank. However, the sediment entering the tank settles to the bottom of the tank, causing siltation in the tank compartment that is difficult to clean, affecting the normal operation of the sedimentation tank. Traditional sedimentation tanks settle sediment by reducing the flow velocity of the sediment-carrying water flow. The sedimentation effect is better for larger sediment particles. For water flows with a large sediment content, if you want to further improve the sedimentation efficiency, you must expand the scale of the sedimentation tank, resulting in a large project investment. Traditional sedimentation tanks are generally suitable for water flows with an inflow sediment content of less than 80kg / m 3 When the sediment content in the pool is greater than 100kg / m 3 When the above value occurs, the sand content of the water flowing out of the pool exceeds the use requirements, and the silt accumulation at the bottom of the pool is serious, which will further reduce the siltation efficiency and the sedimentation pool needs to stop operating.

[0004] For water diversion projects on channels with high sediment content, simply reducing the flow rate cannot make the sediment content out of the pool meet the water supply requirements. After a large amount of sediment settles and accumulates, the sedimentation effect of the sedimentation pool will drop sharply, seriously affecting the normal operation of the entire water intake project. Summary of the invention

[0005] In order to solve the above problems, the present invention proposes an alternating vertical filtration overflow water intake type sedimentation tank. The continuous sand flushing vertical filtration overflow water intake type sedimentation tank effectively reduces the sand content out of the tank by controlling the entry of large-particle sediment into the tank, continuous real-time sand flushing through multi-stage bottom holes, vertical filtration sedimentation and surface overflow water intake, etc., and flushes the sediment accumulated on the bottom of the tank in real time, thereby improving the operating efficiency of the sedimentation tank and facilitating operation and management.

[0006] The specific technical solutions are as follows:

[0007] An alternating vertical filtering overflow water intake type sedimentation tank, comprising a first diffusion section 1, a primary sedimentation tank 2, an overflow section 3, a second diffusion section 4 and a secondary sedimentation tank 5 arranged in sequence according to the direction of water flow, the cross sections of the first diffusion section 1 and the second diffusion section 4 are both trumpet-shaped, and the narrow mouth of the trumpet corresponds to the water inlet end;

[0008] The end of the first diffusion section 1 away from the primary sedimentation tank 2 is connected to the water diversion channel 7 through the first sluice gate 61;

[0009] The primary sedimentation tank 2 includes a first water inlet section 21 and a primary filter section 22 in sequence according to the water flow direction. The upper part of the primary filter section 22 is a horizontally arranged primary filter tank 221, and the lower part of the primary filter section 22 is a primary water flow channel. The primary water flow channel is connected to the primary filter tank 221, and the bottom of the primary filter tank 221 is paved with a first reverse filter layer 222. The outlet of the primary water flow channel is connected to the outside through a sand flushing culvert 81.

[0010] The secondary sedimentation tank 5 includes a second water inlet section 51 and a secondary filter section 52 in sequence according to the water flow direction. The upper part of the secondary filter section 52 is a horizontally arranged secondary filter tank 521, and the lower part of the secondary filter section 52 is a secondary water flow channel. The secondary water flow channel is connected to the secondary filter tank 521, and the bottom of the secondary filter tank 521 is paved with a second reverse filter layer 522. The outlet of the secondary water flow channel is connected to the outside through a second-stage sand flushing culvert 82.

[0011] The water flow of the water diversion channel 7 flows through the first diffusion section 1, the first water inlet section 21, the primary filter section 22, the overflow section 3, the second diffusion section 4, the second water inlet section 51 and the secondary filter section 52 in sequence; in the primary filter section 22, the water flows through the primary water flow channel into the primary filter tank 221, and after filtration, the overflow flows into the overflow section 3; in the secondary filter section 52, the water flows through the secondary water flow channel into the secondary filter tank 521, and after filtration, the overflow flows into the water outlet 523, and water can be taken in through the water intake steel pipe 524.

[0012] The first-level filter tank 221 is surrounded by flow-blocking walls on all sides and a section of rectifying plate 223 on the bottom. The height of the flow-blocking walls on both sides of the first-level filter tank 221 is lower than the height of the wall of the first-level sedimentation tank 2, forming a pair of overflow waterways 224.

[0013] The height of the baffle wall at the water inlet end of the primary filter tank 221 is the same as the height of the pool wall of the primary sedimentation tank 2, and the height of the baffle wall at the water outlet end of the primary filter tank 221 is lower than the height of the pool wall of the primary sedimentation tank 2 to form a water collection port 225, which is connected to the overflow section 3;

[0014] The first-stage rectifying plate 223 is evenly provided with water holes corresponding to the first-stage water flow channel, so that the first-stage water flow channel is connected with the first-stage filter tank 221;

[0015] The primary water flow channel is two parallel first tank boxes 23.

[0016] A first partition wall 24 is arranged in the extension direction of the partition wall of the pool chamber between the two first pool boxes 23, and the first partition wall 24 extends to the first water inlet section 21 and the first diffusion section 1 in sequence, so as to evenly divide the inlet water of the primary sedimentation tank 2 into two streams;

[0017] A sand flushing bottom hole 231 is provided in the middle of the bottom of each of the first tanks 23, and the sand flushing bottom holes 231 are arranged along the extension direction of the first tank 23, and the water outlet ends of the two sand flushing bottom holes 231 are connected, and are connected to the first section of the sand flushing culvert 81 through the second sluice gate 62 respectively.

[0018] The secondary filter tank 521 is surrounded by the walls of the secondary sedimentation tank 5 on both sides, the baffle walls at both ends, and two sections of rectifier plates 525 at the bottom, and a partition baffle wall 526 is provided in the middle of the secondary filter tank 521 to separate the secondary filter tank 521 into two parallel square tanks;

[0019] The height of the baffle wall at the water inlet end of each square trough is the same as the height of the wall of the secondary siltation tank 5, and the height of the baffle wall at the water outlet end of each square trough is lower than the height of the wall of the secondary siltation tank 5 to form a water outlet 523, and water can be taken from the water outlet 523 through a water intake steel pipe 524, and a valve is provided at the water inlet end of each water intake steel pipe 524;

[0020] The second-stage rectifying plate 525 is evenly provided with water holes corresponding to the secondary water flow channel, so that the secondary water flow channel is connected with the secondary filter tank 521;

[0021] The secondary water flow channel is composed of six parallel second tank boxes 53 , and the water outlet ends of each second tank box 53 are connected and connected to the second-stage sand flushing culvert 82 through the third sluice gate 63 .

[0022] Second partition walls 54 are evenly arranged in the extension direction of the partition walls of the chambers between adjacent second tank boxes 53, and each second partition wall 54 extends to the second water inlet section 51, so as to evenly divide the inlet water of the secondary desilting tank 5 into 6 streams, and each stream flows into the corresponding second tank box 53;

[0023] The bottom of each of the second tank boxes 53 is provided with an inclined retaining wall 531 and a triangular retaining wall 532, so that two sand flushing grooves are formed along the longitudinal extension direction of the bottom of the second tank box 53, and the vertical section of each sand flushing groove is an inverted trapezoid.

[0024] The first filter layer 222 and the second filter layer 522 have the same structure, which are a 100-mesh steel wire mesh and a 1-meter-thick filter layer from bottom to top, and the filter material of the filter layer is graded gravel with a particle size of 3 mm to 10 mm.

[0025] The middle part of the second diffusion section 4 is surrounded by a baffle wall to form a non-water flow area with a diamond-shaped cross-section, and one symmetry axis of the rhombus is consistent with the water flow direction, and gaps are left between the corresponding baffle walls at both ends of the other symmetry axis and the corresponding side walls of the second diffusion section 4 to form a pair of water flow outlets, and a fourth water gate 64 is provided on each water flow outlet.

[0026] The first water gate 61 and the water diversion channel 7 are obliquely intersected at 30° to 60°, and the bottom sill of the first water gate 61 is 0.2 m higher than the channel bottom.

[0027] The diffusion angle of the first diffusion section 1 is 20°, and the slope ratio of the bottom of the first diffusion section 1 is 1:6; the diffusion angle of the second diffusion section 4 is 25°, and the slope ratio of the bottom of the second diffusion section 4 is 1:10; the bottom slope of the secondary sedimentation tank 5 is ≤2°.

[0028] The overflow section 3 is a curved overflow weir, the weir top of the overflow weir adopts a WES profile, and the net width of the weir surface of the overflow weir is 6.0m.

[0029] The alternating vertical filtering overflow water intake type sedimentation tank of the present invention comprises a first diffusion section, a primary sedimentation tank, an overflow section, a second diffusion section and a secondary sedimentation tank which are arranged in sequence according to the water flow direction; the first sluice gate and the water diversion channel are obliquely intersected at 30° to 60°, and water is diverted obliquely; water in the primary sedimentation tank flows into the primary filter tank through the water emitting holes on a section of rectifying plate, and after being filtered by a section of filtering layer, flows into the water collection port from a pair of overflow water channels, and overflows from the baffle wall at the water outlet end of the primary filter tank into the water collection port; water in the secondary sedimentation tank flows into the secondary filter tank through the water emitting holes on the second section of rectifying plate, and after being filtered by the second reverse filter layer, overflows from the baffle wall at the water outlet end of the secondary filter tank into the water outlet, sediments downward, and water is taken upward; the above oblique water diversion and upward water intake method effectively filters large particles of sediment into the tank.

[0030] The diffusion angle of the first diffusion section of the present invention is 20°, the bottom slope ratio is less than 1:5, the longitudinal slope of the first sedimentation tank is not less than 1%, the water outlet ends of the two sand flushing bottom holes of the first sedimentation tank are connected, and are respectively connected to the section of sand flushing culvert through the second sluice gate, so the sediment at the bottom of the first sedimentation tank can be flushed continuously and in real time by controlling the second sluice gate.

[0031] The diffusion angle of the second diffusion section is 25°, the bottom slope ratio is not steeper than 1:10, the longitudinal slope of the second sedimentation tank is not less than 1%, and the water outlet ends of each second tank box of the second sedimentation tank are connected, and are respectively connected to the two sections of sand flushing culverts through the third sluice gate. Therefore, the sediment at the bottom of the second sedimentation tank can be flushed in real time and continuously by controlling the third sluice gate; the above-mentioned real-time and continuous sand flushing avoids siltation of fine sand, ensures the effective capacity of the sedimentation tank, and improves the sedimentation efficiency.

[0032] The primary sedimentation tank and the secondary sedimentation tank of the present invention are arranged in series, and the two square tanks of the secondary sedimentation tank are arranged in parallel. The bottom of each square tank corresponds to three second tank boxes, which can make large and small particle size sediments settle in grades and gradually improve the sediment settling rate.

[0033] Therefore, the alternating vertical filtration overflow water intake type sedimentation tank of the present invention is used in the water diversion project of the channel with high sediment content, realizing oblique water diversion, upward water intake, real-time continuous sand flushing, and graded sedimentation. 3 When the sediment settling amount is 90.8%, the sediment content out of the pool is less than 12kg / m 3 The particle size of the sediment leaving the pool is less than 0.05mm. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 It is a structural schematic diagram of the alternating vertical filtration overflow water intake type sedimentation tank of the present invention.

[0035] Figure 2 for Figure 1 AA cross-sectional top view.

[0036] Figure 3 for Figure 1 Enlarged view of the water inlet end.

[0037] Figure 4 for Figure 1 Enlarged view of the water outlet.

[0038] Figure 5 for Figure 2 Enlarged view of point I.

[0039] Figure 6 for Figure 2 Enlarged view of point II.

[0040] Figure 7 This is the BB cross-sectional view.

[0041] Figure 8 This is the CC section view.

[0042] Serial numbers in the above figure are: 1 first diffusion section, 2 first sedimentation tank, 21 first water inlet section, 22 first filter section, 221 first filter tank, 222 first filter layer, 223 first rectifier plate, 224 a pair of overflow channels, 225 water collection port, 23 first tank box, 231 sand flushing bottom hole, 24 first partition wall, 3 overflow section, 4 second diffusion section, 5 second sedimentation tank, 61 first sluice gate, 62 second sluice gate, 64 third sluice gate, 7 water diversion channel, 81 first sand flushing culvert, 82 second sand flushing culvert, 51 second water inlet section, 52 second filter section, 521 second filter tank, 522 second filter layer, 523 water outlet, 524 water intake steel pipe, 525 second rectifier plate, 526 partition baffle wall, 53 second tank box, 531 inclined retaining wall, 532 triangular retaining wall, 54 second partition wall. DETAILED DESCRIPTION

[0043] The present invention will be further described below by way of embodiments in conjunction with the accompanying drawings. Example

[0044] An alternating vertical filtration overflow water intake type sedimentation tank, see Figure 1-2 , including a first diffusion section 1, a primary sedimentation tank 2, an overflow section 3, a second diffusion section 4 and a secondary sedimentation tank 5 which are arranged in sequence according to the direction of water flow. The cross-sections of the first diffusion section 1 and the second diffusion section 4 are both trumpet-shaped, and the narrow mouth of the trumpet corresponds to the water inlet end.

[0045] The middle part of the second diffusion section 4 is surrounded by a baffle wall to form a non-water flow area with a diamond-shaped cross-section, and one symmetry axis of the rhombus is consistent with the water flow direction, and gaps are left between the corresponding baffle walls at both ends of the other symmetry axis and the corresponding side walls of the second diffusion section 4 to form a pair of water flow outlets, and a fourth water gate 64 is provided on each water flow outlet.

[0046] The first sluice gate 61 and the water diversion channel 7 are obliquely intersected at 30° to 60°, and the sill of the first sluice gate 61 is 0.2 m higher than the channel bottom, so as to prevent the larger particle size sediment from entering the primary sedimentation tank 2.

[0047] The diffusion angle of the first diffusion section 1 is 20°, and the slope ratio of the bottom of the first diffusion section 1 is 1:6; the diffusion angle of the second diffusion section 4 is 25°, and the slope ratio of the bottom of the second diffusion section 4 is 1:10; the bottom slope of the secondary sedimentation tank 5 is ≤2°.

[0048] The overflow section 3 is a curved overflow weir, the weir top of the overflow weir adopts a WES profile, and the net width of the weir surface of the overflow weir is 6.0m.

[0049] The end of the first diffusion section 1 away from the primary sedimentation tank 2 is connected to the water diversion channel 7 through the first sluice gate 61;

[0050] The primary sedimentation tank 2 includes a first water inlet section 21 and a primary filter section 22 in sequence according to the water flow direction. The upper part of the primary filter section 22 is a horizontally arranged primary filter tank 221, and the lower part of the primary filter section 22 is a primary water flow channel. The primary water flow channel is connected to the primary filter tank 221, and the bottom of the primary filter tank 221 is paved with a first reverse filter layer 222. The outlet of the primary water flow channel is connected to the outside through a sand flushing culvert 81.

[0051] The secondary sedimentation tank 5 includes a second water inlet section 51 and a secondary filter section 52 in sequence according to the water flow direction. The upper part of the secondary filter section 52 is a horizontally arranged secondary filter tank 521, and the lower part of the secondary filter section 52 is a secondary water flow channel. The secondary water flow channel is connected to the secondary filter tank 521, and the bottom of the secondary filter tank 521 is paved with a second reverse filter layer 522. The outlet of the secondary water flow channel is connected to the outside through a second-stage sand flushing culvert 82.

[0052] The water flow of the water diversion channel 7 flows through the first diffusion section 1, the first water inlet section 21, the primary filter section 22, the overflow section 3, the second diffusion section 4, the second water inlet section 51 and the secondary filter section 52 in sequence; in the primary filter section 22, the water flows through the primary water flow channel into the primary filter tank 221, and after filtration, the overflow flows into the overflow section 3; in the secondary filter section 52, the water flows through the secondary water flow channel into the secondary filter tank 521, and after filtration, the overflow flows into the water outlet 523, and water can be taken in through the water intake steel pipe 524.

[0053] See Figure 5 and Figure 7 The first-level filter tank 221 is surrounded by flow-blocking walls on all sides and a section of rectifying plate 223 on the bottom. The height of the flow-blocking walls on both sides of the first-level filter tank 221 is lower than the height of the wall of the first-level sedimentation tank 2, forming a pair of overflow waterways 224.

[0054] The height of the baffle wall at the water inlet end of the first-level filter tank 221 is the same as the height of the pool wall of the first-level sedimentation tank 2, and the height of the baffle wall at the water outlet end of the first-level filter tank 221 is lower than the height of the pool wall of the first-level sedimentation tank 2 to form a water collection port 225, and the water collection port 225 is connected to the overflow section 3; water holes are evenly opened on the first-level water flow channel corresponding to the first-level rectifying plate 223, so that the first-level water flow channel and the first-level filter tank 221 are connected; the first-level water flow channel is two parallel first pool boxes 23.

[0055] A first partition wall 24 is arranged in the extension direction of the partition wall of the pool chamber between the two first pool boxes 23, and the first partition wall 24 extends to the first water inlet section 21 and the first diffusion section 1 in sequence, so as to evenly divide the inlet water of the primary sedimentation tank 2 into two streams;

[0056] See Figure 3A sand flushing bottom hole 231 is provided in the middle of the bottom of each of the first pool boxes 23, and the sand flushing bottom holes 231 are arranged along the extension direction of the first pool box 23, and the water outlet ends of the two sand flushing bottom holes 231 are connected, and are connected to the first section of the sand flushing culvert 81 through the second sluice gate 62 respectively.

[0057] See Figure 6 and Figure 8 The secondary filter tank 521 is surrounded by the walls of the secondary sedimentation tank 5 on both sides, the baffle walls at both ends, and the two-stage rectifier plates 525 at the bottom, and a partition baffle wall 526 is provided in the middle of the secondary filter tank 521 to separate the secondary filter tank 521 into two parallel square tanks;

[0058] The height of the baffle wall at the water inlet end of each square trough is the same as the height of the wall of the secondary siltation tank 5, and the height of the baffle wall at the water outlet end of each square trough is lower than the height of the wall of the secondary siltation tank 5 to form a water outlet 523, and water can be taken from the water outlet 523 through a water intake steel pipe 524, and a valve is provided at the water inlet end of each water intake steel pipe 524;

[0059] The second-stage rectifying plate 525 is evenly provided with water holes corresponding to the secondary water flow channel, so that the secondary water flow channel is connected with the secondary filter tank 521;

[0060] See Figure 4 The secondary water flow channel is composed of six parallel second tank boxes 53, and the water outlet ends of each second tank box 53 are connected and connected to the second-stage sand flushing culvert 82 through the third sluice gate 63 respectively.

[0061] Second partition walls 54 are evenly arranged in the extension direction of the partition walls of the chambers between adjacent second tank boxes 53, and each second partition wall 54 extends to the second water inlet section 51, so as to evenly divide the inlet water of the secondary desilting tank 5 into 6 streams, and each stream flows into the corresponding second tank box 53;

[0062] The bottom of each of the second tank boxes 53 is provided with an inclined retaining wall 531 and a triangular retaining wall 532, so that two sand flushing grooves are formed along the longitudinal extension direction of the bottom of the second tank box 53, and the vertical section of each sand flushing groove is an inverted trapezoid.

[0063] The first filter layer 222 and the second filter layer 522 have the same structure, which are a 100-mesh steel wire mesh and a 1-meter-thick filter layer from bottom to top, and the filter material of the filter layer is graded gravel with a particle size of 3 mm to 10 mm.

[0064] Regulations for process control operation during sedimentation: The general requirements for engineering control operation are reasonable scheduling, real-time sand flushing, and continuous water supply;

[0065] Specifically, the first sluice gate 61 can prevent the larger silt in the water diversion channel 7 from entering the sedimentation system. The sand-containing water flows into the primary sedimentation tank 2, and the water flows into the primary filter tank 221 through the water holes on a section of the rectifying plate 223. After being filtered by the first filter layer 222, the water flows into the water collection port 225 from a pair of overflow waterways 224 and overflows from the baffle wall at the outlet of the primary filter tank 221 into the water collection port 225. At the same time, more silt is deposited into the sand flushing bottom hole 231, which can be continuously flushed in real time by controlling the second sluice gate 62. When the sediment content in the pool is 120kg / m 3 When the sediment settling amount is 90.8%, the sediment content out of the pool is less than 12kg / m 3 The particle size of the sediment leaving the pool is less than 0.05mm.

[0066] The adjustments made during operation include: increasing the water flow from the water diversion channel 7 (not less than 1.0m 3 / s), to meet the water demand during the sand flushing period; at the same time, in order to meet the need to quickly fill the secondary sedimentation tank 5, the water flow rate of the water collection port 225 of the primary sedimentation tank 2 should not be less than 0.5m 3 / s; When the filling of the secondary sedimentation tank 5 is completed, the fourth sluice gate 64 is closed to achieve immediate flow interruption. When the clean water in the secondary sedimentation tank 5 is emptied, the water outlet of the primary sedimentation tank 2 is adjusted in time through the fourth sluice gate 64, and the sediment at the bottom of the inverted trapezoidal box 53 of the second tank is flushed with a large amount of water.

[0067] (1) In the alternating vertical filtration overflow water intake type sedimentation tank of the present invention, water in the primary sedimentation tank 2 flows through the water emitting holes on a section of the rectifying plate 223 into the primary filter tank 221, and after being filtered through a section of the filter layer, flows into the water collection port 225 from a pair of overflow waterways 224, and overflows from the baffle wall at the outlet end of the primary filter tank 221 into the water collection port 225;

[0068] The water in the secondary sedimentation tank 5 flows into the secondary filter tank 521 through the water holes on the second-stage rectifying plate 525, and after being filtered by the second reverse filter layer 522, overflows from the baffle wall at the outlet end of the secondary filter tank 521 and enters the outlet 523.

[0069] This overflow water intake method of sinking sand downward and taking water upward effectively increases the sedimentation rate of fine-grained sediment.

[0070] (2) The diffusion angle of the first diffusion section is about 20°, the bottom slope ratio is less than 1:5, the longitudinal slope of the first sedimentation tank 2 is not less than 1%, and the water outlets of the two sand flushing bottom holes 231 of the first sedimentation tank 2 are connected, and are respectively connected to the first sand flushing culvert 81 through the second water gate 62. Therefore, the sediment at the bottom of the first sedimentation tank 2 can be flushed continuously in real time by controlling the second water gate 62.

[0071] The diffusion angle of the second diffusion section is about 25°, the bottom slope ratio is not steeper than 1:10, the longitudinal slope of the second sedimentation tank 5 is not less than 1%, and the outlet ends of each second tank box 53 of the second sedimentation tank 5 are connected, and are connected to the two-stage sand flushing culvert 82 through the third water gate 63 respectively. Therefore, the sediment at the bottom of the second sedimentation tank 5 can be flushed continuously in real time by controlling the third water gate 63.

[0072] Real-time continuous sand flushing can avoid the accumulation of fine sand, ensure the effective capacity of the sedimentation tank, and improve the sedimentation efficiency.

[0073] (3) The secondary filter tank 521 is divided into two parallel square tanks by the separation group flow 526. At the same time, three second tank boxes 53 correspond to the bottom of each square tank. By controlling the two fourth water gates 64, the two square tanks can be operated alternately to filter the sediment, ensuring that the two square tanks are operated alternately every 6 hours or so. At this time, the filter material in the square tank that is not in operation can be cleaned or replaced. Regular cleaning or replacement of the filter material can effectively ensure continuous water supply.

[0074] (4) Water is taken from the water outlet 523 through the water intake steel pipe 524. A valve is provided at the water inlet end of each water intake steel pipe 524 to ensure that the water at the water outlet 523 is evenly and safely transported.

Claims

1. An alternating vertical filtration overflow water intake type sedimentation tank, characterized in that: It comprises a first diffusion section (1), a primary sedimentation tank (2), an overflow section (3), a second diffusion section (4) and a secondary sedimentation tank (5) which are arranged in sequence according to the direction of water flow, wherein the cross sections of the first diffusion section (1) and the second diffusion section (4) are both trumpet-shaped, and the narrow mouth of the trumpet corresponds to the water inlet end; One end of the first diffusion section (1) away from the primary sedimentation tank (2) is connected to the water diversion channel (7) via a first sluice gate (61); The primary sedimentation tank (2) comprises a first water inlet section (21) and a primary filtering section (22) in sequence according to the water flow direction; the upper portion of the primary filtering section (22) is a horizontally arranged primary filtering tank (221); the lower portion of the primary filtering section (22) is a primary water flow channel; the primary water flow channel is connected to the primary filtering tank (221); a first reverse filter layer (222) is provided at the bottom of the primary filtering tank (221); and an outlet of the primary water flow channel is connected to the outside through a sand flushing culvert (81); The secondary sedimentation tank (5) comprises a second water inlet section (51) and a secondary filtering section (52) in sequence according to the water flow direction; the upper part of the secondary filtering section (52) is a horizontally arranged secondary filtering tank (521); the lower part of the secondary filtering section (52) is a secondary water flow channel; the secondary water flow channel is connected to the secondary filtering tank (521); a second reverse filter layer (522) is laid on the bottom of the secondary filtering tank (521); and the outlet of the secondary water flow channel is connected to the outside through a second-stage sand flushing culvert (82); During operation, water from the water diversion channel (7) flows sequentially through the first diffusion section (1), the first water inlet section (21), the primary filtering section (22), the overflow section (3), the second diffusion section (4), the second water inlet section (51) and the secondary filtering section (52); in the primary filtering section (22), water flows through the primary water flow channel into the primary filtering tank (221), and after filtering, the overflow flows into the overflow section (3); in the secondary filtering section (52), water flows through the secondary water flow channel into the secondary filtering tank (521), and after filtering, the overflow flows into the water outlet (523), and water can be taken in through the water intake steel pipe (524).

2. According to claim 1, an alternating vertical filtration overflow water intake type sedimentation tank is characterized by: The primary filter tank (221) is surrounded by flow-blocking walls on all sides and a section of rectifying plate (223) on the bottom. The height of the flow-blocking walls on both sides of the primary filter tank (221) is lower than the height of the wall of the primary sedimentation tank (2), forming a pair of overflow waterways (224). The height of the baffle wall at the water inlet end of the primary filter tank (221) is the same as the height of the pool wall of the primary sedimentation tank (2), and the height of the baffle wall at the water outlet end of the primary filter tank (221) is lower than the height of the pool wall of the primary sedimentation tank (2) to form a water collection port (225), and the water collection port (225) is connected to the overflow section (3); Water holes are evenly provided on the rectifying plate (223) corresponding to the primary water flow channel, so that the primary water flow channel is connected to the primary filter tank (221); The primary water flow channel is two parallel first tank boxes (23).

3. According to claim 2, an alternating vertical filtration overflow water intake type sedimentation tank is characterized by: A first partition wall (24) is arranged in the extension direction of the partition wall of the tank chamber between the two first tank boxes (23), and the first partition wall (24) extends successively into the first water inlet section (21) and the first diffusion section (1), so as to evenly divide the inlet water of the primary sedimentation tank (2) into two water flows; A sand flushing bottom hole (231) is provided in the middle of the bottom of each of the first tanks (23), and the sand flushing bottom holes (231) are arranged along the extension direction of the first tank (23), and the water outlet ends of the two sand flushing bottom holes (231) are connected and are connected to the first section of the sand flushing culvert (81) through the second sluice gate (62).

4. The alternating vertical filtration overflow water intake type sedimentation tank according to claim 1, characterized in that: The secondary filter tank (521) is surrounded by the walls of the secondary sedimentation tank (5) on both sides, flow-blocking walls at both ends, and two sections of rectifying plates (525) at the bottom, and a partition flow-blocking wall (526) is provided in the middle of the secondary filter tank (521) to separate the secondary filter tank (521) into two parallel square tanks; The height of the baffle wall at the water inlet end of each square trough is the same as the height of the wall of the secondary sedimentation tank (5), and the height of the baffle wall at the water outlet end of each square trough is lower than the height of the wall of the secondary sedimentation tank (5) to form a water outlet (523), and water can be taken from the water outlet (523) through a water intake steel pipe (524), and a valve is provided at the water inlet end of each water intake steel pipe (524); The second-stage rectifying plate (525) is evenly provided with water holes corresponding to the secondary water flow channel, so that the secondary water flow channel is connected to the secondary filter tank (521); The secondary water flow channel is composed of six parallel second tank boxes (53), the water outlet ends of each second tank box (53) are connected and are connected to the second-stage sand flushing culvert (82) through the third water gate (63).

5. The alternating vertical filtration overflow water intake type sedimentation tank according to claim 4, characterized in that: Second partition walls (54) are evenly arranged in the extension direction of the partition walls of the tank chambers between adjacent second tank boxes (53), and each second partition wall (54) extends to the second water inlet section (51), so as to evenly divide the inlet water of the secondary sedimentation tank (5) into six water flows, and each water flow flows into the corresponding second tank box (53); The bottom of each of the second tank boxes (53) is provided with an inclined retaining wall (531) and a triangular retaining wall (532), so that two sand flushing grooves are formed along the longitudinal extension direction of the bottom of the second tank box (53), and the vertical cross-section of each sand flushing groove is an inverted trapezoid.

6. The alternating vertical filtration overflow water intake type sedimentation tank according to claim 1, characterized in that: The first filter layer (222) and the second filter layer (522) have the same structure, which are, from bottom to top, a 100-mesh steel wire mesh and a 1-meter-thick filter layer, and the filter material of the filter layer is graded gravel with a particle size of 3 mm to 10 mm.

7. The alternating vertical filtration overflow water intake type sedimentation tank according to claim 1, characterized in that: The middle part of the second diffuser section (4) is surrounded by a flow-blocking wall to form a non-water flow area with a rhombus-shaped cross section, and one symmetry axis of the rhombus is consistent with the water flow direction, and gaps are left between the corresponding flow-blocking walls at both ends of the other symmetry axis and the corresponding side walls of the second diffuser section (4) to form a pair of water flow outlets, and each water flow outlet is provided with a fourth water gate (64).

8. The alternating vertical filtration overflow water intake type sedimentation tank according to claim 1, characterized in that: The first water gate (61) and the water diversion channel (7) are obliquely intersected at an angle of 30° to 60°, and the bottom sill of the first water gate (61) is 0.2 m higher than the channel bottom.

9. The alternating vertical filtration overflow water intake type sedimentation tank according to claim 1, characterized in that: The diffusion angle of the first diffusion section (1) is 20°, and the slope ratio of the bottom of the first diffusion section (1) is 1:6; the diffusion angle of the second diffusion section (4) is 25°, and the slope ratio of the bottom of the second diffusion section (4) is 1:10; the bottom slope of the secondary sedimentation tank (5) is ≤2°.

10. The alternating vertical filtration overflow water intake type sedimentation tank according to claim 1, characterized in that: The overflow section (3) is a curved overflow weir, the top of the overflow weir adopts a WES profile, and the net width of the overflow weir surface is 6.0 m.

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