Intelligent salty water avoiding and dredging system and method for estuary reservoir

Abstract

The invention discloses an intelligent salty-avoiding dredging system and method for an estuary reservoir. The intelligent salty-avoiding dredging system comprises a reservoir defined by an external dam and an internal dam, a reservoir gate, a silt flushing gate, a front flushing nozzle array, a flow guide groove, a plurality of rotatable sills and a monitoring control unit. The external dam is provided with an overflow weir matched with the average high tide level, and the monitoring control unit comprises a sonar detector, a water level sensor, a conductivity sensor, a tide level meter and a control module. Water is stored during flood tide, and saline water is intercepted through the sill; when the tide level is low, the bottom sill is controlled to rotate to achieve seawater directional silt flushing, and silt is discharged to the deep sea through the flow guide groove and the desilting gallery; when the water level of the reservoir drops to a threshold value, slightly opening a reservoir gate to form a salt-pressing flow field, and adjusting the opening degree of the gate through water conductivity to replace salt water; and after replacement is completed, the sluice gate is closed firstly, then the reservoir gate is closed, and salt tide blocking is achieved. Tidal energy is used for saving water and energy, the silt washing efficiency is improved through directional diversion of the sill, intelligent regulation and control are achieved in the whole process, the salt avoiding effect is good, and water consumption for dredging is low.

Description

Technical Field

[0001] This invention relates to the field of water conservancy engineering dredging technology, and in particular to an intelligent saltwater avoidance and dredging system and method for estuary reservoirs. Background Technology

[0002] As an important drinking water source and water conservancy hub in the coastal area, the Hekou Reservoir is located at the intersection of land and sea and is significantly affected by the tidal dynamics of the open sea. Its outlet area is prone to siltation. After siltation, not only will the reservoir's flood discharge and water intake capacity be greatly reduced, but the water flow field in the outlet area will also be disrupted, exacerbating the vicious cycle of weakened tidal dynamics.

[0003] Existing estuary reservoir dredging technologies are mainly divided into two categories: mechanical dredging and hydraulic flushing. Mechanical dredging equipment requires large investments and has high operating costs, and it also causes significant disturbance to the reservoir water. Traditional hydraulic flushing relies heavily on high-powered pumps to extract freshwater from the reservoir area for flushing, which not only consumes a large amount of precious freshwater resources but also has the problem of high electricity consumption. Some technologies attempt to use seawater for auxiliary flushing to save freshwater, but due to the density difference between fresh and saltwater, high-concentration saltwater can easily flow back into the reservoir along the bottom through density currents. Existing technologies lack precise means of preventing saltwater intrusion and replacing saltwater, which can easily lead to salinization of the reservoir water and affect water supply security.

[0004] Existing flushing and siltation technologies have poor water flow guidance, resulting in uneven flushing and siltation coverage and secondary siltation. Furthermore, the gate opening and flushing timing rely heavily on manual experience for control, making it impossible to achieve intelligent dynamic adjustment based on tidal changes, siltation status, and saline residue. Consequently, the dredging efficiency and salinity avoidance effects are insufficient to meet the needs of routine operation and management of estuary reservoirs. Summary of the Invention

[0005] Purpose of the Invention: The purpose of this invention is to provide an intelligent salinity avoidance and dredging system for estuarine reservoirs that offers excellent salinity avoidance and comprehensive dredging and sediment removal. Another purpose of this invention is to provide an intelligent salinity avoidance and dredging method for estuarine reservoirs that integrates salinity avoidance and dredging operations and precisely controls gate opening based on real-time water quality monitoring.

[0006] Technical Solution: The present invention discloses an intelligent saltwater avoidance and dredging system for estuary reservoirs, comprising a reservoir constructed on the estuary side and enclosed by an outer dike and an inner dike, further comprising reservoir gates on the inner dike, siltation gates located on the outlet side of the reservoir and connected at both ends to the outer and inner dikes respectively, a pre-flush array located below the siltation gates and deployed in the siltation area, a diversion channel located on the seabed of the siltation area and in front of the siltation gates, multiple rotatable sills arranged parallel to the seabed of the siltation area and located beside the diversion channel, and a monitoring and control unit for monitoring tide levels, siltation data, and controlling the opening of each gate and the rotation angle of the sills; an overflow weir is provided on the top of the outer dike, the height of which is adapted to the local average high tide level; in the non-siltation state, the sills are parallel to the coastline, and seawater overflows into the reservoir through the outer dike; in the siltation state, according to the siltation data, the monitoring and control unit controls the sills to rotate to the corresponding angle, changing the discharge direction.

[0007] Furthermore, the end of the diversion channel away from the siltation gate is connected to the entrance of the sand discharge corridor via an arc-shaped connecting section, and the outlet of the sand discharge corridor leads directly to the deep sea area.

[0008] Preferably, a debris screen is provided on the outside of the overflow weir to intercept floating debris from the sea surface that enters the reservoir.

[0009] Furthermore, the sill is connected to a rotating mechanism that drives the sill to rotate horizontally within the range of 0 to 90 degrees. The rotating mechanism is controlled by a monitoring and control unit to adjust the rotation angle of the sill.

[0010] Furthermore, the monitoring and control unit includes a sonar detector located outside the reservoir gate to determine whether the siltation thickness exceeds a preset threshold, a water level sensor deployed inside the reservoir to identify real-time water level changes, a conductivity sensor deployed throughout the scour and sedimentation area to monitor the water conductivity in the scour and sedimentation area in real-time, a tide gauge located outside the reservoir gate to identify the real-time tide level in the estuary area, and a control module. The sonar detector, water level sensor, conductivity sensor, and tide gauge are all signal-connected to the control module, which is controllably connected to the drive mechanisms of the reservoir gate, the scour and sedimentation gate, and the sill. When the water level sensor detects that the water level in the reservoir has dropped to a preset threshold, the control module controls the reservoir gate to open, with an initial opening degree of 5% to 10%. When the conductivity sensor detects that the water conductivity is higher than a preset threshold, the control module increases the opening degree of the reservoir gate; when the conductivity sensor detects that the water conductivity has decreased, the control module decreases the opening degree of the reservoir gate. Intelligent dynamic control of gate opening is achieved through closed-loop regulation of conductivity, ensuring thorough brine replacement without any waste of fresh water.

[0011] A method for intelligent salinity avoidance and dredging of estuary reservoirs using the above-mentioned systems includes the following steps:

[0012] S1. At high tide, seawater enters the reservoir through the overflow weir. The debris net intercepts floating debris on the sea surface until the water level in the reservoir is level with the open sea. At this time, the bottom sill remains parallel to the coastline to intercept heavy brine intrusion from the bottom.

[0013] S2. At low tide, the control module controls the bottom sill to rotate to a preset deflection angle based on the sedimentation data fed back by the sonar detector. At the same time, the siltation gate is opened, and the seawater in the reservoir is pressurized and ejected through the front nozzle array to guide the siltation flow to directionally flush the sediment in the siltation area. The sediment is collected through the diversion channel and the arc-shaped connecting section to the sand discharge corridor and discharged into the deep sea area.

[0014] S3. When the water level sensor detects that the water level in the reservoir has dropped to a preset low threshold, the control module controls the reservoir gate to open at an initial opening of 5% to 10%, using the fresh water in the reservoir to form an outward pressure salinity flow field. At the same time, based on the real-time monitoring data of the conductivity sensor, the opening of the reservoir gate is adjusted to direct the heavy brine remaining in the siltation area into the sediment discharge corridor.

[0015] S4. When the conductivity sensor detects that the conductivity of the water in the scouring and silting area has stabilized and dropped to the preset safety setting value, the control module first closes the scouring and silting gate, and then closes the reservoir gate, so that the scouring and silting area is covered by fresh water and the saltwater backflow is blocked.

[0016] Furthermore, in step S2, the control module adjusts the deflection angle of the bottom sill in real time based on the sediment distribution cloud map fed back by the sonar detector, ensuring that the flushing water flow covers the flushing area without any dead corners, thereby improving the flushing efficiency and thoroughness.

[0017] Beneficial effects: Compared with the prior art, the present invention has the following significant advantages:

[0018] (1) By utilizing tidal energy to achieve passive energy storage and directional sludge flushing of seawater, the power consumption is reduced. Only a small amount of fresh water is released by slightly opening the reservoir gate during the salt water replacement stage, which saves fresh water resources and significantly reduces the operating cost of reservoir dredging.

[0019] (2) By precisely adjusting the angle of multiple rotatable bottom sills, the directional guidance of the silt-removing water flow can be achieved, thus solving the problem of uneven silt-removing coverage in traditional methods;

[0020] (3) In the non-scour and siltation state, multiple bottom sills physically intercept the flow, and the gate opening is controlled by the pressure saline flow field and conductivity closed-loop regulation during the freshwater replacement stage, so as to completely block the backflow of saline density flow, ensure that there is no saline residue in the scour and siltation area, and ensure the safety of the reservoir water supply quality.

[0021] (4) Data is monitored in real time using various sensors, with no human intervention throughout the process and intelligent control. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the overall planar structure of the present invention;

[0023] Figure 2 This is a schematic diagram of the bottom sill structure in this invention;

[0024] Figure 3 This is a schematic diagram of the structure of the silt-removing gate and the front-mounted nozzle array in this invention;

[0025] Figure 4 This is a schematic diagram of the process for the intelligent saltwater avoidance and dredging method for estuary reservoirs according to the present invention. Detailed Implementation

[0026] The technical solution of the present invention will be further described below with reference to the accompanying drawings.

[0027] like Figure 1 As shown, this invention discloses an intelligent salinity avoidance and dredging system for an estuary reservoir. An outer dike 4 and an inner dike 3 are constructed on the estuary side, forming a reservoir 2. The outer side of the outer dike 4 is the ocean 14, and the inner side of the inner dike is a freshwater reservoir 1. A reservoir gate 8 is installed on the inner dike 3, and a silt flushing gate 7 is installed on the outlet side of the reservoir 2. The two ends of the silt flushing gate 7 are connected to the outer dike 4 and the inner dike 3, respectively. A pre-flush nozzle array 6 is located below the silt flushing gate 7, directly facing the area of ​​siltation. A high-pressure water pump 5 is used in conjunction with the pre-flush nozzle array 6. The pressurized seawater is ejected through the small-diameter nozzles of the pre-flush nozzle array, forming a high-pressure directional jet. The front flushing nozzle array 6 and the flushing and silting gate 7 form a flushing and silting area 11. A guide channel 10 is set on the seabed of the flushing and silting area 11. Multiple rotatable bottom sills 9 are also arranged in parallel on the seabed of the flushing and silting area 11 next to the guide channel 10. At the same time, the system is also equipped with a monitoring and control unit, which can realize real-time monitoring of tide level and sediment deposition data, and can adjust the opening degree of each gate and the rotation angle of the bottom sills 9 according to the monitoring data.

[0028] like Figure 1 , Figure 3 As shown, an overflow weir 16 is installed at the top of the outer dike 4. The elevation of the overflow weir 16 is adapted to the average high tide level of the project site. During high tide, seawater can naturally flow into the reservoir through the overflow weir 16 to complete energy storage. A debris screen 17 is installed on the outside of the overflow weir 16. During the process of seawater flowing into the reservoir 2, the debris screen 17 can effectively intercept floating seaweed, plastic, debris, etc., preventing various floating objects from entering the reservoir 2 and clogging the flushing gate 7, the front flushing nozzle array 6, or the guide channel 10, thus ensuring the normal operation of all functional components of the system.

[0029] The end of the diversion channel 10 away from the siltation gate 7 is connected to the inlet of the sand discharge corridor 13 through the arc-shaped connecting section 12. The outlet of the sand discharge corridor 13 extends directly to the deep sea area. The arc-shaped connecting section 12 can realize the smooth transition of water flow and sediment between the diversion channel 10 and the sand discharge corridor 13, avoiding sediment settling and accumulation at the structural connection. The design of the sand discharge corridor 13 extending directly to the deep sea area can transport the flushed sediment over long distances, effectively preventing secondary siltation caused by sediment backflow.

[0030] Each sill 9 is connected to a corresponding rotating mechanism, which drives the sill 9 to rotate horizontally within a range of 90°. The rotating mechanism is linked to the monitoring and control unit, which issues action commands to regulate the operation of the rotating mechanism to achieve precise adjustment of the sill 9's rotation angle. The rotating mechanism can be either hydraulically driven or electrically driven; both methods are suitable for the harsh operating conditions of high salinity, high humidity, and easy siltation on the seabed, ensuring the stability and accuracy of the sill 9's angle adjustment. When the system is not in a scouring / silting state, all sills 9 remain parallel to the coastline, physically intercepting the heavy brine at the bottom. When the system enters a scouring / silting state, the monitoring and control unit precisely controls each sill 9 to rotate to the corresponding angle based on the collected sediment distribution data, thereby changing the discharge direction of the scouring / silting water flow and achieving directional water flow guidance.

[0031] The monitoring and control unit consists of a sonar detector, a water level sensor, a conductivity sensor, a tide gauge, and a control module, such as... Figure 2 As shown, the various sensors in the monitoring and control unit are schematically represented as sensor group 15. Their actual distribution is as follows: A sonar detector is deployed outside the reservoir gate 8 to scan and monitor the morphology and thickness of sediment deposition in the scour and siltation area 11, and to determine whether the deposition thickness exceeds a preset threshold. A water level sensor is deployed inside the reservoir 2 to collect and identify water level changes in the reservoir 2 in real time. Conductivity sensors are deployed throughout the scour and siltation area 11 to monitor the water conductivity in the area in real time. A tide gauge is deployed outside the reservoir gate 8 to accurately identify real-time tide changes in the estuary area. The sonar detector, water level sensor, conductivity sensor, and tide gauge are all connected to the control module, allowing various monitoring data to be transmitted to the control module in real time. The control module then forms a control connection with the rotating mechanisms of the reservoir gate 8, the scour and siltation gate 7, and the sill 9, issuing control commands based on the monitoring data.

[0032] When the water level sensor detects that the water level in reservoir 2 has dropped to a preset low threshold, the control module will automatically issue an opening command to control the reservoir gate 8 to open. The initial opening degree of the reservoir gate 8 is set to 5% to 10%. This opening degree, while ensuring that a sufficiently powerful saline-alkali flow field is formed after the freshwater flows out of the reservoir, effectively pushes away the residual heavy brine in the siltation zone 11, reducing the discharge of freshwater from the reservoir area. Based on the monitoring data of the conductivity sensor, the control module realizes dynamic closed-loop control of the opening degree of the reservoir gate 8. When the conductivity sensor detects that the conductivity of the water in the siltation zone 11 is higher than the preset safety threshold, the control module will automatically adjust to increase the opening degree of the reservoir gate 8, increasing the freshwater outflow to enhance the saline-alkali flow field. When the conductivity sensor detects that the conductivity of the water in the siltation zone 11 is showing a continuous downward trend, the control module will automatically adjust to decrease the opening degree of the reservoir gate 8, further reducing freshwater consumption while ensuring the brine replacement effect. This regulation method ensures both thorough replacement of saline water in the siltation zone 11 and the rational utilization of freshwater resources.

[0033] like Figure 1 , Figure 4 As shown, a method for intelligent salinity avoidance and dredging of estuary reservoirs utilizing the above system includes the following steps:

[0034] S1. During high tide, seawater flows into reservoir 2 through overflow weir 16. The debris net 17 intercepts floating debris on the sea surface until the water level in reservoir 2 is level with the open sea. At this time, the bottom sill 9 remains parallel to the coastline. The principle of density current is used to intercept the heavy salt water intrusion from the bottom layer, realizing the passive storage of tidal energy and preventing saltwater backflow.

[0035] S2. At low tide, the control module adjusts the deflection angle of the bottom sill 9 in real time based on the sediment distribution cloud map fed back by the sonar detector to ensure that the siltation flow fully covers the siltation area 11 without any dead corners, thereby improving the efficiency and thoroughness of siltation. At the same time, the siltation gate 7 is opened, and the seawater in the reservoir 2 is pressurized and ejected by the front nozzle array 6 under the action of potential energy and the pressure of the high-pressure water pump 5. The bottom sill guides the siltation flow to directionally flush the sediment in the siltation area 11. The crushed sediment is collected through the diversion channel 10, transitioned through the arc-shaped connecting section 12, and finally discharged into the sand discharge corridor 13 and transported to the deep sea area.

[0036] S3. When the water level sensor detects that the water level in the reservoir 2 has dropped to a preset low threshold, the control module controls the reservoir gate 8 to open with an initial opening of 5% to 10%. The pressure difference between the fresh water in the reservoir and the siltation area forms an outward pressure saline flow field. At the same time, the opening of the reservoir gate 8 is dynamically adjusted based on the real-time monitoring data of the conductivity sensor, so as to continuously push and directionally discharge the heavy brine remaining in the siltation area 11 into the sand discharge corridor 13.

[0037] S4. When the conductivity sensor detects that the conductivity of the water in the siltation area 11 has stabilized and dropped to the preset safety setting value, the control module first closes the siltation gate 7, and then closes the reservoir gate 8, so that the siltation area 11 is finally covered by fresh water, completely blocking the backflow of saltwater.

[0038] This invention utilizes tidal energy for water and energy conservation. The bottom sill is designed to be rotatable, providing physical interception in non-flushing / silting conditions to avoid density currents. In flushing / silting conditions, the sill rotates, acting as a guide to direct saline water flow and improve flushing efficiency. When the water level in the reservoir drops, the sill, in conjunction with a slight opening of the reservoir gate, creates a saline-pressure flow field, and the gate opening is adjusted according to changes in water conductivity. This comprehensive salinity avoidance system provides superior results.

Claims

1. A smart salinity avoidance and dredging system for a river estuary reservoir, comprising a reservoir (2) constructed on the estuary side and enclosed by an outer dike (4) and an inner dike (3), characterized in that, It also includes a reservoir gate (8) on the inner dike (3), a siltation gate (7) on the outlet side of the reservoir (2) and connected at both ends to the outer dike (4) and the inner dike (3) respectively, a front-mounted nozzle array (6) located below the siltation gate (7) and arranged in the siltation area, a diversion channel (10) located on the seabed of the siltation area (11) and in front of the siltation gate (7), and parallel arrangements on the seabed of the siltation area (11) and located beside the diversion channel (10). Multiple rotatable sills (9) and a monitoring and control unit for monitoring tide levels, siltation data and controlling the opening of each gate and the rotation angle of the sills (9); the top of the external dike (4) is provided with an overflow weir (16), the height of which is adapted to the local average high tide level; in the non-scouring and silting state, the sills are parallel to the coastline, and seawater overflows into the reservoir through the external dike; in the scouring and silting state, according to the siltation data, the monitoring and control unit controls the sills to rotate to the corresponding angle to change the discharge direction.

2. The intelligent salinity avoidance and dredging system for estuary reservoirs according to claim 1, characterized in that, The end of the diversion channel (10) away from the siltation gate (7) is connected to the entrance of the sand discharge corridor (13) via an arc-shaped connecting section (12), and the outlet of the sand discharge corridor (13) leads directly to the deep sea area.

3. The intelligent salinity avoidance and dredging system for estuary reservoirs according to claim 1, characterized in that, The overflow weir (16) is provided with a debris screen (17) on the outside to intercept floating debris entering the reservoir (2).

4. The intelligent salinity avoidance and dredging system for estuary reservoirs according to claim 1, characterized in that, The bottom sill (9) is connected to a rotating mechanism that drives the bottom sill (9) to rotate horizontally within the range of 0~90°. The rotating mechanism is controlled by a monitoring and control unit to adjust the rotation angle of the bottom sill (9).

5. The intelligent salinity avoidance and dredging system for estuary reservoirs according to claim 1, characterized in that, The monitoring and control unit includes a sonar detector located outside the reservoir gate (8) for determining whether the siltation thickness exceeds a preset threshold, a water level sensor located inside the reservoir (2) for real-time identification of water level changes, a conductivity sensor located throughout the scour and sedimentation area (11) for real-time monitoring of the water conductivity of the scour and sedimentation area (11), a tide gauge located outside the reservoir gate (8) for identifying the real-time tide level in the estuary area, and a control module. The sonar detector, water level sensor, conductivity sensor, and tide gauge are all connected to the control module via signal. The control module is connected to the drive mechanism of the reservoir gate (8), the scour and sedimentation gate (7), and the sill (9).

6. The intelligent salinity avoidance and dredging system for estuary reservoirs according to claim 5, characterized in that, When the water level sensor detects that the water level in the reservoir (2) has dropped to a preset threshold, the control module controls the reservoir gate (8) to open, and the initial opening degree of the reservoir gate (8) is 5% to 10%.

7. The intelligent salinity avoidance and dredging system for estuary reservoirs according to claim 5, characterized in that, When the conductivity sensor detects that the water conductivity is higher than the preset threshold, the control module increases the opening of the reservoir gate (8); when the conductivity sensor detects that the water conductivity is lower, the control module decreases the opening of the reservoir gate (8).

8. A method for intelligent salinity avoidance and dredging of estuary reservoirs using the system described in any one of claims 1-7, characterized in that, Includes the following steps: S1. At high tide, seawater enters the reservoir (2) through the overflow weir (16). The sludge net (17) intercepts floating debris on the sea surface until the water level in the reservoir (2) is level with the open sea. At this time, the bottom sill (9) remains parallel to the coastline to intercept the heavy salt water intrusion from the bottom layer. S2. At low tide, the control module controls the bottom sill (9) to rotate to the preset deflection angle based on the sedimentation data fed back by the sonar detector, and at the same time opens the siltation gate (7). The seawater in the reservoir (2) is pressurized and ejected through the front nozzle array (6) to guide the siltation water flow to directionally flush the sediment in the siltation area (11). The sediment is collected through the diversion channel (10) and the arc-shaped connecting section (12) to the sand discharge corridor (13) and discharged to the deep sea area. S3. When the water level sensor detects that the water level in the reservoir (2) has dropped to a preset low threshold, the control module controls the reservoir gate (8) to open at an initial opening of 5% to 10%, using the fresh water in the reservoir to form an outward pressure salinity flow field. At the same time, based on the real-time monitoring data of the conductivity sensor, the opening of the reservoir gate (8) is adjusted to direct the heavy brine remaining in the siltation area (11) into the sand discharge corridor (13). S4. When the conductivity sensor detects that the conductivity of the water in the siltation area (11) has stabilized and dropped to the preset safety setting value, the control module first closes the siltation gate (7) and then closes the reservoir gate (8) so that the siltation area (11) is covered by fresh water and the saltwater backflow is blocked.

9. The intelligent salinity avoidance and dredging method for estuary reservoirs according to claim 8, characterized in that, In step S2, the control module adjusts the deflection angle of the bottom sill (9) in real time according to the sediment distribution cloud map fed back by the sonar detector, so as to ensure that the siltation flow covers the siltation area (11).

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