Water intake structure for sediment-laden rivers

Abstract

The present invention discloses a water intake structure, in particular a water intake structure for a multi-sediment river channel, belonging to the technical field of the design and construction of water conservancy and hydropower engineering structures. A water intake structure for a multi-sediment river channel that can meet the requirements of sand prevention during water intake in periods with large flood-season flows is provided. The water intake structure includes an overflow dam. The water intake structure further includes a sedimentation and water intake composite system. The water flow in the reservoir area upstream of the overflow dam is filtered for sand-laden water through the sedimentation and water intake composite system and then input into the power station downstream.

Description

Technical Field

[0001] The present invention relates to a water intake structure, in particular to a water intake structure for a multi-sediment river course, belonging to the technical field of design and construction of water conservancy and hydropower engineering structures. Background Art

[0002] The structural characteristics of the conventional layout scheme of diversion-type hydropower stations with prominent sediment problems in mountainous areas are as follows: 1. The headworks consists of an overflow dam, a sediment flushing sluice, a water intake, a diversion tunnel, etc.; 2. The overflow dam is transversely arranged in the river course, mainly used to raise the river water level; 3. The sediment flushing sluice is arranged on one side of the river course, mainly used to discharge the sediment deposited in the river course in front of the overflow dam; 4. The water intake is arranged adjacent to the sediment flushing sluice, and its axis intersects the river course at a large angle; 5. The elevation of the overflow dam crest > the elevation of the water intake bottom slab > the elevation of the sediment flushing sluice bottom slab. The advantages of this structure are: 1. The layout of the headworks buildings is compact, and the project quantity is relatively less; 2. During the dry season and the period with small flow rates in the flood season, when the sediment content in the water flow is small, due to the reduction of the flow velocity in front of the dam, the sediment in the water flow will deposit in the reservoir in front of the overflow dam under the action of gravity, and relatively low-sediment-content water flow can be obtained through the water intake. The main problems of this structure are: 1. During the period with large flow rates in the flood season, the sediment content of the upstream incoming flow is large. Due to the large discharge of the overflow dam and the large flow velocity of the water flow in front of the dam, the sediment in the upstream incoming flow will enter the water intake before it has time to deposit, thus causing wear to the flow channels and water turbine units of the hydropower station; 2. To avoid the above situation, some hydropower stations adopt the measure of "closing the water intake gate, avoiding sand, and not generating electricity", which will also cause a certain amount of power loss. Summary of the Invention

[0003] The technical problem to be solved by the present invention is: to provide a water intake structure for a multi-sediment river course that can meet the requirements of water intake and sand prevention during the period with large flow rates in the flood season.

[0004] The technical solution adopted to solve the above technical problem is: a water intake structure for a multi-sediment river course, including an overflow dam. The water intake structure further includes a sedimentation and water intake composite system. The water flow in the reservoir area upstream of the overflow dam is filtered for sand and input into the downstream power station through the sedimentation and water intake composite system.

[0005] Furthermore, the sedimentation and water intake composite system includes a river sedimentation and flushing and discharging mechanism and a water intake sedimentation and flushing and discharging mechanism. The river sedimentation and flushing and discharging mechanism is arranged at one end of the overflow dam, and the water intake sedimentation and flushing and discharging mechanism adjacent to the river sedimentation and flushing and discharging mechanism is arranged on the side bank of the river course on the upper side of the overflow dam.

[0006] The preferred mode of the above solution is that the river sedimentation and flushing and discharging mechanism includes at least two sets of sediment flushing sluice chamber components, and each set of the sediment flushing sluice chamber components is arranged in parallel at one end of the overflow dam.

[0007] Furthermore, the water intake and sedimentation flushing and discharging mechanism includes a water intake, a secondary sedimentation flushing and discharging component, and a water intake and conveying component. The secondary sedimentation flushing and discharging component is communicated with the river channel on the upstream side of the overflow dam through the water intake, and the water intake and conveying component is communicated with the secondary sedimentation flushing and discharging component.

[0008] In a preferred embodiment of the above solution, the water intake and conveying component includes a diversion tunnel, and the inlet end of the diversion tunnel is communicated with the secondary sedimentation flushing and discharging component.

[0009] Furthermore, the secondary sedimentation flushing and discharging component includes a water diversion and conveying channel, a sedimentation tank, and a sand flushing channel. The sedimentation tank is connected to the water intake through the water diversion and conveying channel, and the diversion tunnel and the sand flushing channel are respectively connected to the sedimentation tank at the same time.

[0010] In a preferred embodiment of the above solution, the secondary sedimentation flushing and discharging component further includes a sand flushing and water conveying channel. The inlet end of the sand flushing and water conveying channel is connected to the water intake, and the outlet end of the sand flushing and water conveying channel is connected to the middle and lower part of the sedimentation tank.

[0011] Furthermore, the sedimentation tank and the water diversion and conveying channel are arranged in a humpback structure. The inlet end of the diversion tunnel is connected to the end of the water diversion and conveying channel, and the inlet end of the sand flushing channel is located at the far end of the sedimentation tank arranged in a humpback structure.

[0012] In a preferred embodiment of the above solution, the secondary sedimentation flushing and discharging component further includes a control gate chamber. At least one set of the control gate chamber is respectively arranged at the inlet end of the diversion tunnel, the inlet end of the water diversion and conveying channel, the inlet end of the sand flushing and water conveying channel, and the inlet end of the sand flushing channel.

[0013] Furthermore, the projection of the sedimentation tank arranged in a humpback structure on the horizontal plane is an isosceles trapezoid, the width of which gradually decreases from upstream to downstream, and the bottom elevation of which gradually decreases from upstream to downstream.

[0014] The beneficial effect of the present invention is that: the water intake structure provided in this application is based on the existing overflow dam. By adding a sedimentation and water intake composite system, the water flow in the reservoir area upstream of the overflow dam is filtered for sand-carrying and then input into the power station downstream. In this way, when there is a large amount of sand in the water flow, especially during the flood season, as the water flow with a large amount of sediment from the mountains enters the river channel and then enters the water intake area of the power station along the river channel, the sedimentation and water intake composite system of this application first precipitates and filters the sediment in the water flow, and then inputs it into the generators in the power station downstream. Therefore, it can meet the water intake and sand prevention requirements during the period of large flood season flow. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a plan layout view of the water intake structure for multi-sediment river channels of the present invention.

[0016] In the figure, the markings are: overflow dam 1, river channel sedimentation flushing and discharging mechanism 2, water intake sedimentation flushing and discharging mechanism 3, flushing sluice chamber assembly 4, water intake 5, secondary sedimentation flushing and discharging assembly 6, water intake conveying assembly 7, water diversion conveying channel 8, sedimentation tank 9, flushing channel 10, flushing water conveyance channel 11, control sluice chamber 12. Specific implementation mode

[0017] As Figure 1 Shown is a water intake structure for a multi-sediment river provided by the present invention, which can meet the water intake and sand prevention requirements during the period of large flow in the flood season. The water intake structure includes an overflow dam 1, and the water intake structure further includes a sedimentation and water intake composite system. The water flow in the reservoir area upstream of the overflow dam 1 is filtered for entrained sand through the sedimentation and water intake composite system and then input into the downstream power station. The water intake structure provided in this application is based on the existing overflow dam. By adding a sedimentation and water intake composite system and enabling the water flow in the reservoir area upstream of the overflow dam to pass through the sedimentation and water intake composite system to filter the entrained sand and then input it into the downstream power station. In this way, when there is a large amount of entrained sand in the water flow, especially during the flood season, when the water flow with a large amount of sediment brought by mountain water enters the river channel and then enters the water intake area of the power station along the river channel, the sediment in the water flow is first precipitated and filtered by the sedimentation and water intake composite system of this application, and then input into the generators in the downstream power station, so as to meet the water intake and sand prevention requirements during the period of large flow in the flood season.

[0018] In the above implementation mode, in order to make the water intake structure of this application more convenient for construction and subsequent use in combination with the characteristics of the existing water intake structure, the sedimentation and water intake composite system described in this application includes a river channel sedimentation flushing and discharging mechanism 2 and a water intake sedimentation flushing and discharging mechanism 3. The river channel sedimentation flushing and discharging mechanism 2 is arranged at one end of the overflow dam 1, and the water intake sedimentation flushing and discharging mechanism 3 adjacent to the river channel sedimentation flushing and discharging mechanism 2 is arranged on the side bank of the river channel on the upper side of the overflow dam 1. At this time, the river channel sedimentation flushing and discharging mechanism 2 described in this application is set to include at least two sets of flushing sluice chamber assemblies 4, and each set of the flushing sluice chamber assemblies 4 is arranged in parallel at one end of the overflow dam 1. Correspondingly, the water intake sedimentation flushing and discharging mechanism 3 includes a water intake 5, a secondary sedimentation flushing and discharging assembly 6, and a water intake conveying assembly 7. The secondary sedimentation flushing and discharging assembly 6 is communicated with the river channel on the upstream side of the overflow dam 1 through the water intake 5, and the water intake conveying assembly 7 is communicated with the secondary sedimentation flushing and discharging assembly 6. At this time, the water intake conveying assembly 7 includes a diversion tunnel, and the inlet end of the diversion tunnel is communicated with the secondary sedimentation flushing and discharging assembly 6. The secondary sedimentation flushing and discharging assembly 6 includes a water diversion conveying channel 8, a sedimentation tank 9, and a flushing channel 10. The sedimentation tank 9 is connected to the water intake 10 through the water diversion conveying channel 8, and the diversion tunnel and the flushing channel 10 are respectively connected to the sedimentation tank 9 at the same time.

[0019] Further, the secondary sediment flushing and discharging assembly 6 described in the present application further includes a sediment flushing water channel 11. The inlet end of the sediment flushing water channel 11 is connected to the water intake 5, and the outlet end of the sediment flushing water channel 11 is connected to the middle and lower part of the sedimentation tank. The sedimentation tank 9 and the water diversion and conveying channel 8 are arranged in a hunchback structure. The inlet end of the water diversion tunnel is connected to the end of the water diversion and conveying channel 8, and the inlet end of the sediment flushing channel 10 is located at the far end of the sedimentation tank 9 arranged in a hunchback structure. To facilitate the control of the water flow of each component, the secondary sediment flushing and discharging assembly 6 further includes a control gate chamber 12. At least one set of the control gate chamber 12 is respectively arranged at the inlet end of the water diversion tunnel, the inlet end of the water diversion and conveying channel 8, the inlet end of the sediment flushing water channel 11, and the inlet end of the sediment flushing channel 10.

[0020] Certainly, for the convenience of construction, the projection of the sedimentation tank 9 arranged in a hunchback structure in the present application in the horizontal plane is an isosceles trapezoid, the width of which gradually decreases from upstream to downstream, and the bottom elevation of which gradually decreases from upstream to downstream.

[0021] Specifically, the main operation mode and working principle of the water intake structure described in the present application are as follows:

[0022] 1) During the dry season and the flood season with a small upstream inflow, the sediment content in the upstream inflow is relatively small. Close the sediment flushing gate, the lower water channel gate, and the sediment flushing channel gate, and open the upper water channel gate and the water diversion tunnel gate. The upstream inflow reaches in front of the overflow dam. Due to the reduced flow velocity, the sediment in the water flow will settle in the reservoir in front of the overflow dam under the action of gravity, and the water flow will enter the sedimentation tank through the water intake and the upper water channel. After filling the sedimentation tank, it will enter the water diversion tunnel and reach the downstream power plant for power generation.

[0023] 2) During the flood season with a large upstream inflow, the sediment content in the upstream inflow is relatively large. Close the sediment flushing gate, the upper water channel gate, and the sediment flushing channel gate, and open the lower water channel gate and the water diversion tunnel gate. The upstream inflow reaches in front of the overflow dam. Due to the large flow velocity, it enters the water intake before it has time to settle; after entering the sedimentation tank through the lower water channel, due to the reduced flow velocity, the sediment settles under the action of gravity and moves along the slope of the bottom plate of the sedimentation tank to the bottom of the sedimentation tank; the water flow after the sediment settlement will enter the water diversion tunnel through the water diversion tunnel gate arranged at the top of the sedimentation tank and reach the downstream power plant for power generation.

[0024] 3) During the flood season when the upstream incoming flow is large, when the sediment deposited in the sedimentation tank approaches the elevation of the bottom slab of the intake tunnel of the diversion tunnel, close the gates of the sediment flushing sluice, the lower water conveyance channel, and the diversion tunnel, and open the gates of the upper water conveyance channel and the sediment flushing channel. The upstream incoming flow will enter the top of the sedimentation tank through the upper water conveyance channel, and the sediment deposited in the tank will be discharged downstream along the bottom slope of the sedimentation tank through the sediment flushing channel; since the plane of the sedimentation tank is arranged in an isosceles shape, the closer to the outlet of the sedimentation tank, the smaller the width, the deeper the water depth, and the higher the flow velocity of the sedimentation tank, and the sediment flushing effect in the sedimentation tank will be more obvious.

[0025] 4) During the flood season when the upstream incoming flow is large, when it is found that the sediment deposition in the reservoir is relatively serious and may affect the safe operation of the power station, close the gates of the upper water conveyance channel, the lower water conveyance channel, the diversion tunnel, and the sediment flushing channel, and open the gate of the sediment flushing sluice, then the upstream incoming flow can be used to discharge the sediment within a certain range upstream of the sediment flushing sluice downstream through the sediment flushing sluice.

[0026] In summary, the water intake structure provided by this application for water intake and power generation in a sediment-laden river also has the following advantages.

[0027] 1) During the dry season and the flood season when the upstream incoming flow is small, the sediment content of the upstream incoming flow is small, and the upstream incoming flow will directly enter the diversion tunnel through the water intake and the upper water conveyance channel to generate electricity in the downstream power house, without causing significant wear to the flow passage and water turbine unit of the hydropower station.

[0028] 2) During the flood season when the flow rate is large, the sediment content of the upstream incoming flow is large. Even if the sediment content of the water flow through the water intake and the lower water conveyance channel is large, due to the sedimentation effect of the sedimentation tank, the sediment content of the water flow entering the diversion tunnel will be significantly reduced, and it will not cause significant wear to the flow passage and water turbine unit of the hydropower station, and also reduces the power loss caused by shutting down the machine to avoid sediment during the flood season.

[0029] 3) When the sediment deposition in the sedimentation tank affects the safety of the power station, only by adjusting the opening and closing states of the gates of the upper water conveyance channel, the lower water conveyance channel, the diversion tunnel, and the sediment flushing channel, the automatic flushing of the sedimentation tank can be realized, and the operation is relatively convenient.

[0030] Embodiment 1

[0031] The technical problem to be solved by this application is to provide a water intake and sediment discharge structure for a diversion-type hydropower station that meets the requirements of water intake and sand prevention during the flood season when the flow rate is large.

[0032] The technical solution adopted by this application to solve the technical problem is as follows:

[0033] 1) The water intake and sediment discharge structure consists of an overflow dam, a sediment flushing sluice, a water intake, an upper water conveyance channel, a lower water conveyance channel, a sedimentation tank, a sediment flushing channel, and corresponding control gates.

[0034] 2) The overflow dam is transversely arranged in the river channel, used to raise the water level of the river channel and discharge flood during the flood season.

[0035] 3) The sediment flushing sluice is arranged on one side of the river channel, used to discharge the sediment silted in the river channel in front of the overflow dam.

[0036] 4) The water intake is arranged adjacent to the sediment flushing sluice, and its axis intersects the river channel at a large angle. The water intake is connected to the upper water conveyance channel and the lower water conveyance channel, and upper water conveyance channel gates and lower water conveyance channel gates are set to control the water flow.

[0037] 5) The upper water conveyance channel is connected to the upstream of the diversion tunnel and the upstream of the sedimentation basin, and the lower water conveyance channel is connected to the downstream of the sedimentation basin.

[0038] 6) The plan of the sedimentation basin is an isosceles trapezoid, and its width gradually decreases from upstream to downstream; the elevation of the bottom slab of the sedimentation basin gradually decreases from upstream to downstream.

[0039] 7) The downstream end of the sedimentation basin is connected to the sediment flushing channel, and a sediment flushing channel gate is set to control the water flow. The outlet of the sediment flushing channel is located downstream of the overflow dam.

[0040] 8) The diversion tunnel is laterally arranged at the upstream end of the sedimentation basin, and a diversion tunnel gate is set to control the water flow.

[0041] 9) The elevation of the crest of the overflow dam > the elevation of the bottom slab of the water intake > the elevation of the bottom slab of the sediment flushing sluice, and the elevation of the bottom slab of the water intake = the elevation of the bottom slab of the upper water conveyance channel = the elevation of the bottom slab of the lower water conveyance channel = the elevation of the inlet bottom slab of the diversion tunnel > the elevation of the bottom slab of the sediment flushing channel.

Claims

1. A water intake structure for a sediment-laden river channel, comprising an overflow dam (1), characterized in that: The water intake structure further includes a sedimentation and water intake composite system. The water flow in the reservoir area upstream of the overflow dam (1) passes through the sedimentation and water intake composite system to filter out the sandwiched sediment and is input into the power station downstream, The sedimentation and water intake composite system includes a river channel sedimentation and flushing mechanism (2) and a water intake sedimentation and flushing mechanism (3). The river channel sedimentation and flushing mechanism (2) is arranged at one end of the overflow dam (1), and the water intake sedimentation and flushing mechanism (3) adjacent to the river channel sedimentation and flushing mechanism (2) is arranged on the side bank of the river channel on the upper side of the overflow dam (1), The water intake sedimentation and flushing mechanism (3) includes a water intake (5), a secondary sedimentation and flushing assembly (6) and a water intake conveying assembly (7). The secondary sedimentation and flushing assembly (6) is connected to the river channel on the upstream side of the overflow dam (1) through the water intake (5), and the water intake conveying assembly (7) is connected to the secondary sedimentation and flushing assembly (6), The water intake conveying assembly (7) includes a diversion tunnel. The inlet end of the diversion tunnel is connected to the secondary sedimentation and flushing assembly (6), The secondary sedimentation and flushing assembly (6) includes a water diversion and conveying channel (8), a sedimentation tank (9) and a flushing channel (10). The sedimentation tank (9) is connected to the water intake (5) through the water diversion and conveying channel (8), and the diversion tunnel and the flushing channel (10) are respectively connected to the sedimentation tank (9) at the same time, The secondary sedimentation and flushing assembly (6) further includes a flushing water conveyance channel (11). The inlet end of the flushing water conveyance channel (11) is connected to the water intake (5), and the outlet end of the flushing water conveyance channel (11) is connected to the middle and lower part of the sedimentation tank, The water intake (5) is arranged adjacent to the flushing sluice, and its axis intersects the river channel at a large angle.

2. The water intake structure for a sediment-laden river channel according to claim 1, characterized in that: The river channel sedimentation and flushing mechanism (2) includes at least two sets of flushing sluice chamber assemblies (4), and each set of the flushing sluice chamber assemblies (4) is arranged in parallel at one end of the overflow dam (1).

3. The water intake structure for a sediment-laden river channel according to claim 1 or 2, characterized in that: The sedimentation tank (9) and the water diversion and conveying channel (8) are arranged in a humpback structure. The inlet end of the diversion tunnel is connected to the end of the water diversion and conveying channel (8), and the inlet end of the flushing channel (10) is located at the far end of the sedimentation tank (9) arranged in a humpback structure.

4. The water intake structure for a sediment-laden river channel according to claim 3, characterized in that: The secondary sedimentation and flushing assembly (6) further includes a control sluice chamber (12). At least one set of the control sluice chamber (12) is respectively arranged at the inlet end of the diversion tunnel, the inlet end of the water diversion and conveying channel (8), the inlet end of the flushing water conveyance channel (11) and the inlet end of the flushing channel (10).

5. The water intake structure for a sediment-laden river channel according to claim 4, characterized in that: The sedimentation tank (9) arranged in a humpback structure has an isosceles trapezoid projection in the horizontal plane, with its width gradually decreasing from the upstream to the downstream and its bottom elevation gradually decreasing from the upstream to the downstream.

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