Systematic rectification curtain and water bloom prevention and control method

Abstract

The invention discloses a systematic rectification curtain and a water bloom prevention and control method, the systematic rectification curtain comprises a rectification system which is formed by splicing a plurality of curtain units in a laying area and jointly formed by a plurality of rectification curtains, each curtain unit comprises a single split type waterproof curtain, and the single split type waterproof curtain is divided into a surface layer rectification curtain, a middle layer rectification curtain and a bottom layer rectification curtain according to different positions of cross sections of a water body; the lower end of the single split type waterproof curtain is connected with a balancing weight body with an automatic rope winding system through a connecting rope, and a connecting lock catch is arranged at the end of the connecting rope. The systematic rectification curtain provided by the invention can regulate and control regional hydrodynamic force of lakes, reservoirs and rivers, and conditions required for inhibiting growth of algae are easily created; the systematic rectification curtain is formed by splicing a single split type waterproof curtain in a magnetic attraction mode in the transverse direction and is connected with a balancing weight capable of automatically winding a rope and adjusting the gravity center at the water bottom through a lock catch in the vertical direction, and the problems that a traditional rectification curtain is narrow in application range, difficult to determine the arrangement position, incapable of being repeatedly used, high in manufacturing cost, difficult to transport and the like are solved.

Description

Technical Field

[0001] The invention relates to the technical field of river water ecology improvement and water bloom regulation, in particular to a systematic rectifying curtain and a water bloom prevention and control method. Background Art

[0002] With the continuous advancement of industrialization and urbanization in my country, the eutrophication of freshwater lakes and rivers has become a key factor affecting water quality and ecological balance. In recent years, important water bodies in many places, including but not limited to cascade reservoirs, numerous lakes and urban rivers, have experienced varying degrees of algal blooms. Algal blooms not only pose a threat to the diversity of aquatic ecosystems, but also have a profound impact on people's daily water safety and the healthy development of the regional economy. In view of this, it has become particularly urgent to develop innovative and efficient algal bloom control technologies.

[0003] As a mathematical tool to describe the laws of water quality changes, water quality models can simulate and predict the migration and transformation of water bodies in time and space. At present, significant progress has been made in the development and application of water quality models at home and abroad. Some models have shown high maturity and accuracy, which can provide solid scientific theoretical support for water environment quality monitoring, reservoir ecological scheduling, water pollution control, and water resources planning and management. However, there is currently a lack of small and medium-scale watershed algal bloom control strategies that can be used in conjunction with the models, which greatly limits the comprehensive application potential of the models in actual water environment management.

[0004] The principle of rectifying curtain algal bloom prevention and control is to change the hydrodynamic conditions in lakes, reservoirs and rivers that are conducive to the growth and reproduction of algae, change the processes such as energy exchange, water mass mixing, and water body stratification, and then change the main habitat factors that affect the growth and succession of algae, such as light, water temperature and nutrients, making it unfavorable for the growth and reproduction of algae, thereby achieving the purpose of preventing and controlling algal blooms by physical means.

[0005] The existing authorization announcement number is CN207582408U, which is a river-type reservoir algae control device. Through the surface water-blocking curtain, algae can be rapidly multiplied in the upper water body of the upstream flow rich in nutrients, consuming a large amount of nutrients. The remaining nutrients are guided by the water flow to the lower layer with no light and low water temperature where algae are difficult to grow, thereby inhibiting the growth of algae within a certain distance. The authorization announcement number is CN116655025A, which is a water purification and algae control device for rivers entering the reservoir and its use method. On this basis, an algae collection mechanism is added to treat the algae and pollutants concentrated on the front side of the water-blocking curtain.

[0006] The prior art has the following problems and defects: (1) The flow characteristics in lakes, reservoirs and rivers are complex, and it is difficult to determine the specific location for the placement of the rectifying curtain. Random placement may cause local algal blooms and have the opposite effect. (2) It is difficult to create the hydrodynamic conditions required to inhibit algae growth by simply changing the upper water layer with surface curtains. Traditional fixed surface curtains are also unable to adapt to reservoir and river environments with large water level fluctuations. (3) The size of the waterproof curtain needs to be designed according to the river section. Once the width of the river increases, the required curtain will be longer and heavier, which is not only expensive but also extremely difficult to transport, arrange and recycle. Summary of the invention

[0007] The present invention provides a systematic rectifying curtain and water bloom prevention and control method, aiming to solve the problems of existing rectifying curtain design, positioning, transportation, deployment, disassembly and the like, and can adapt to large water level fluctuations, shipping and the like, and has the advantages of strong adaptability, low cost and reusability.

[0008] In order to solve the above technical problems, the technical solution adopted by the present invention is: A systematic rectifying curtain comprises a plurality of curtain units which are detachably connected to each other, each of the curtain units comprises a waterproof curtain, a plurality of floating blocks are detachably provided on the top of the waterproof curtain, a curtain connecting lock hole is provided on the bottom side of the middle position of the waterproof curtain, the curtain connecting lock hole on the bottom side is connected to a connecting lock buckle through a connecting rope, the connecting lock buckle is connected to a counterweight mechanism through another connecting rope, and the connecting rope and the counterweight mechanism form an elastic contraction fit through a coil spring.

[0009] Preferably, magnets are fixedly provided on both sides of the waterproof curtain, and the magnets are symmetrically arranged with respect to the connection lock holes of the bottom curtain, so that the waterproof curtains of adjacent curtain units are magnetically fixedly engaged with each other through the magnets.

[0010] As a more preferred embodiment, the floating blocks include a plurality of detachable floating blocks and embedded fixed floating blocks, and the top of the waterproof curtain is respectively provided with fixing holes and installation holes, and the corresponding embedded fixed floating blocks are snap-fitted and fixedly installed in the fixing holes, and a plurality of detachable floating blocks are detachably snap-fitted and fixedly installed in the installation holes.

[0011] Furthermore, a curtain connection lock hole is provided on the top side of the middle position of the waterproof curtain, there are two fixing holes, and the fixing holes are located on both sides of the top curtain connection lock hole and are symmetrically arranged about the top curtain connection lock hole, the installation hole is located at the top of the curtain connection lock hole, and the middle position of the installation hole coincides with the middle position of the waterproof curtain.

[0012] Furthermore, the top thread of the waterproof curtain is matched with a plurality of clamping screws, and the ends of the clamping screws penetrate into the installation holes to form a clamping and fixing match with the detachable floating block.

[0013] Furthermore, the counterweight mechanism includes a capsule-shaped counterweight outer shell, an installation cavity is provided in the middle position of the counterweight outer shell, a winding disk is provided in the installation cavity, one end of the coil spring is connected to the winding disk and tightened on the winding disk, and the connecting rope passes through the counterweight outer shell and passes through the cleaning brush and the rope limit block in sequence to be connected to the other end of the coil spring to form an elastic scroll fit, the cleaning brush forms a blocking fit with the debris outside the shell, the rope limit block forms a limiting fit with the connecting rope, an adjusting knob is provided on one side of the counterweight outer shell, the adjusting knob forms a linkage fit with the winding disk, a counterweight iron block is provided in the counterweight outer shell located at the bottom of the installation cavity, and the rest of the counterweight outer shell outside the installation cavity is filled with counterweight filling material.

[0014] Specifically, counterweight rope connection holes are provided on both sides of the counterweight outer shell, and the counterweight rope connection holes penetrate the counterweight filling material, and the counterweight rope connection holes are symmetrically arranged with respect to the installation cavity.

[0015] A method for preventing and controlling algal blooms, using the above-mentioned systematic rectifying curtain to adjust water flow to prevent and control algal blooms, comprises the following steps: S1. Collect model boundary data, including inflow and outflow or water level, meteorological conditions, topographic data, flow velocity and water temperature, divide the model calculation grid, and synchronously monitor the flow and water environment of the modeled water area; S2. Determine the initial and boundary conditions of the model based on the data collected in S1, solve the main parameters using the finite difference method based on the CE-QUAL-W2 model, construct a numerical model of river hydrodynamics, and perform model calibration and verification; S3, set different numerical simulation conditions, change the position, number and depth of the rectifier curtain, use the internal weir module of the model in S2 to simulate the rectifier curtain, output the simulation results of each condition, and analyze the impact on water temperature stratification and flow velocity; S4. Select the working conditions that can most significantly improve the water flow characteristics and install the systematic rectification curtain.

[0016] Preferably, the initial conditions in S2 include that the initial water level remains unchanged along the way, the initial flow velocity of the model is set to zero, the inflow conditions are mainly the upstream inflow flow and the inflow water temperature, the water volume in the upper section of the dam is controlled by the inflow and outflow flow, the water volume in the lower section of the dam is characterized by the water level, the water body type is fresh water, and the initial water temperature of the model is set to the observed average value; The boundary conditions in S2 include upstream and downstream inflows and outflows, the water surface boundary, and the riverbed bottom boundary.

[0017] As a more preferred embodiment, the operating conditions of S3 include the condition of no straightening curtain, the condition of a surface straightening curtain installed 500m downstream of the monitoring section, the condition of a bottom straightening curtain installed 300m upstream of the monitoring section, and the condition of straightening curtains installed on the bottom layer 300m upstream of the monitoring section and on the surface 500m downstream at the same time.

[0018] Beneficial effects of the present invention: (1) The present invention provides a systematic rectifying curtain and algal bloom prevention and control method, which can determine the specific location of the rectifying curtain in lakes, reservoirs and rivers with complex water flow characteristics in different regions; (2) The present invention provides a systematic rectifying curtain and a method for preventing and controlling algal blooms. The systematic rectifying curtain can regulate the hydrodynamics of the entire cross section, thereby creating the hydrodynamic conditions required to inhibit the growth of algae. (3) The present invention provides a systematic rectifying curtain and algal bloom prevention and control method. The surface and middle rectifying curtains are combined with a counterweight block with an automatic rope collection system to adapt to reservoirs and rivers with large water level fluctuations. The surface curtain will not float or be completely submerged when the water level rises or falls. (4) The present invention provides a systematic rectifying curtain and a method for preventing and controlling water blooms. The systematic rectifying curtain adopts a split design and is connected by single-sided magnets. Each single curtain can be made separately according to actual applications. The surface rectifying curtain will be separated when a ship passes by and will be adsorbed and closed when the ship leaves, which can meet the navigation function of reservoirs and rivers. The bottom rectifying curtain can adapt to the reservoir and river environment with tortuous underwater terrain; (5) The present invention provides a systematic rectifying curtain and a method for preventing and controlling water blooms. The connecting rope connecting the systematic rectifying curtain and the bottom counterweight block is provided with a connecting lock, which can separate the waterproof curtain from the counterweight block to realize the curtain recovery function. The counterweight block is arranged in a capsule shape to prevent it from getting stuck in the underwater terrain. At the same time, the counterweight blocks are connected to each other by a connecting rope, and can be directly recovered on the river bank by the end connecting rope; (6) The present invention provides a systematic rectifying curtain and water bloom prevention and control method, which is a physical water bloom prevention and control method and will not cause secondary pollution to the environment; the systematic rectifying curtain can be disassembled and reused, which reduces material costs and also reduces the impact on the environment; the systematic rectifying curtain can adapt to large water level fluctuations, and there is no need for personnel to move the curtain up and down, which reduces labor costs and achieves an organic unity of environmental protection, effectiveness and economy. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a split schematic diagram of a systematic rectifying curtain described in the present invention; Figure 2 This is a schematic diagram of the structure of the counterweight block with an automatic rope collection system in the present invention; Figure 3 It is a schematic diagram of another embodiment of the rectifying curtain of the present invention; Figure 4 Schematic diagram of different industrial and mining rectification curtains described in the present invention; Figure 5It is a cross-sectional schematic diagram of the surface layer and bottom layer rectifying curtain cloth of the present invention; Figure 6 A flow chart of a method for systematic rectification curtain and water bloom prevention and control provided by an embodiment of the present invention; Figure 7 A grid division diagram of a hydrodynamic model provided in an embodiment of the present invention; Figure 8 A diagram showing the verification results of flow velocity and water temperature data of important sections of the hydrodynamic model provided by an embodiment of the present invention; Fig. 9 A schematic diagram of partial working condition simulation results of a systematic rectifying curtain provided in an embodiment of the present invention; Fig.10 Changes in horizontal flow velocity of the sections near the upstream and downstream of the monitoring section before and after the actual deployment of the systematic rectifying curtain provided in the embodiment of the present invention (left: below the monitoring section; right: above the monitoring section); Fig.11 A comparison diagram of the water temperature stratification change process near the monitoring section before and after the actual deployment of the systematic rectifying curtain provided in an embodiment of the present invention; Fig.12 A comparison diagram of the PH stratification change process near the monitoring section before and after the actual deployment of the systematic rectifying curtain provided in an embodiment of the present invention; In the figure: 1. Waterproof curtain; 11. Fixing hole; 12. Mounting hole; 2. Floating block; 21. Removable floating block; 22. Embedded fixed floating block; 3. Magnet; 4. Curtain connection lock hole; 5. Connecting rope; 6. Connecting lock buckle; 7. Counterweight mechanism; 71. Counterweight block outer shell; 72. Counterweight block rope connection hole; 73. Rope limit block; 74. Cleaning brush; 75. Winding disk; 76. Adjustment knob; 77. Coil spring; 78. Counterweight iron block; 79. Counterweight filling material; 8. Tightening screw. DETAILED DESCRIPTION

[0020] As follows, embodiments are further described with reference to the accompanying drawings.

[0021] like Figure 1 , Figure 2 , Figure 4 and Figure 5 As shown, as a preferred embodiment 1, a systematic rectifying curtain comprises a plurality of curtain units, which are detachably connected to each other, and each of the curtain units comprises a waterproof curtain 1, and a plurality of floating blocks 2 are detachably provided on the top of the waterproof curtain 1, and a curtain connecting lock hole 4 is provided on the bottom side of the middle position of the waterproof curtain 1, and the curtain connecting lock hole 4 on the bottom side is connected to a connecting lock buckle 6 through a connecting rope 5, and the connecting lock buckle 6 is connected to a counterweight mechanism 7 through another connecting rope 5, and the connecting rope 5 and the counterweight mechanism 7 form an elastic contraction fit through a coil spring 77.

[0022] Preferably, the waterproof curtain 1 can be made of anti-seepage geotextile, with a rounded rectangular shape, a single unit width of 2-5m, and a height of 0.5-10m.

[0023] Preferably, the connecting buckle 6 is a runway-shaped mountaineering buckle made of metal, one end of which is fixed to a counterweight block 7 with an automatic rope collection system at the bottom to prevent the connecting rope 5 from being completely collected into the counterweight block 7, and the other end is connected to the connecting lock hole 4 at the bottom end of the waterproof curtain 1 by the connecting rope 5 or directly. When recovering, the connecting buckle 6 can be unfastened to separate the waterproof curtain 1 and the counterweight block 7 from this end.

[0024] Magnets 3 are fixedly provided on both sides of the waterproof curtain 1. The magnets 3 are symmetrically arranged about the bottom curtain connection lock holes 4. The waterproof curtains 1 of adjacent curtain units are fixedly matched by magnetic attraction through the magnets 3.

[0025] Preferably, the magnet 3 can be a single-sided magnet, with one side of the magnet 3 close to the front side being the magnetic attraction portion, and the other side of the magnet 3 close to the rear side being the magnetic attraction portion. In this way, during arrangement, the rear side of the front waterproof curtain 1 can be magnetically matched with the front side of the rear waterproof curtain 1, and the single rectifying curtains can be spliced ​​into a whole, with one side being weakly magnetic or non-magnetic, which will not affect the underwater habitat.

[0026] The floating blocks 2 include a plurality of detachable floating blocks 21 and embedded fixed floating blocks 22. The top of the water-blocking curtain 1 is provided with a fixing hole 11 and a mounting hole 12, respectively. The fixing holes 11 are all fixedly mounted with corresponding embedded fixed floating blocks 22, and the mounting holes 12 are detachably fixedly mounted with a plurality of detachable floating blocks 21. The detachable floating blocks 21 can adjust the buoyancy of the curtain according to the arrangement mode of the rectifier curtain (surface layer, middle layer, bottom layer), and the embedded fixed floating blocks 22 can ensure that the curtain is stretched in the water.

[0027] A curtain connection lock hole 4 is provided on the top side of the middle position of the waterproof curtain 1, there are two fixing holes 11, and the fixing holes 11 are located on both sides of the top curtain connection lock hole 4 and are symmetrically arranged about the top curtain connection lock hole 4, the installation hole 12 is located at the top of the curtain connection lock hole 4, and the middle position of the installation hole 12 coincides with the middle position of the waterproof curtain 1.

[0028] The counterweight mechanism 7 includes a capsule-shaped counterweight block shell 71, a mounting cavity is provided in the middle position of the counterweight block shell 71, a winding disk 75 is provided in the mounting cavity, one end of the coil spring 77 is connected to the winding disk 75 and tightened on the winding disk 75, and the connecting rope 5 is inserted into the counterweight block shell 71 and is connected to the other end of the coil spring 77 through a cleaning brush 74 and a rope limit block 73 in sequence to form an elastic scroll fit, the cleaning brush 74 forms a blocking fit with the debris outside the shell, the rope limit block 73 forms a limiting fit with the connecting rope 5, an adjusting knob 76 is provided on one side of the counterweight block shell 71, and the adjusting knob 76 forms a linkage fit with the winding disk 75, the winding disk 75 is a fixed rope disk, and the adjusting knob 76 can be rotated to adjust the tightness of the coil spring 77, a counterweight iron block 78 is provided in the counterweight block shell 71 located at the bottom of the mounting cavity, and the rest of the counterweight block shell 71 outside the mounting cavity is filled with counterweight filling material 79.

[0029] Specifically, the counterweight block 7 with an automatic rope collection system has an outer layer of a capsule-shaped outer shell 71, which can prevent the counterweight block 7 from being stuck by the uneven terrain of the bottom of the water; rope connection holes 72 are arranged at both ends of the counterweight block 7, which are connected to each other by a connecting rope. When adjusting the plan, the end connecting rope can be directly recovered on the river bank; a rope limit block 73 is arranged in the internal cavity of the counterweight block 7 to ensure that the connecting rope outlet is vertical, and a cleaning brush 74 is arranged at the outlet to clean the aquatic organisms attached to the connecting rope 5 when it expands and contracts with the water level fluctuation, so as to prevent the connecting rope 5 from getting stuck; a fixed counterweight iron block 78 is arranged at the bottom of the counterweight block 7, and counterweight filling materials 79 are arranged around it, so that the center of gravity of the counterweight can be adjusted according to the bottom terrain of the water. The counterweight filling material (79) is a flowable sand and gravel material, which is filled in the sealed counterweight area around the counterweight block, and large-grained stones can move in the fine sand when the counterweight body is tilted under force.

[0030] The counterweight block outer shell 71 is provided with counterweight block rope connection holes 72 on both sides, and the counterweight block rope connection holes 72 penetrate the counterweight filling material 79, and the counterweight block rope connection holes 72 are symmetrically arranged with respect to the installation cavity.

[0031] Implementation process: In the early stage of preparation, the boundary data of the watershed model is first collected, including inflow and outflow or water level, meteorological conditions, terrain data, flow rate, and water temperature. The numerical model of river hydrodynamics is constructed from the data, and the model is calibrated and verified. Then, the water retaining module (internal weir module) in the model is used to simulate the design of the rectifier curtain, and the position, number and depth of the water retaining module in the model are adjusted. Different working conditions are set to simulate the effect of laying out the rectifier curtain on water temperature stratification and flow rate. The working conditions with the most obvious improvement effect on water flow characteristics and the highest comprehensive environmental and economic benefits are selected, the size of each rectifier curtain is determined, and the number and size of the required single split rectifier curtains are planned.

[0032] When laying, the required number of single split-type rectifier curtains and the corresponding counterweight blocks with automatic rope collection systems are transported to the model design waters, and the surface, middle and bottom rectifier curtains are laid out respectively. For the surface rectifier curtain, the detachable floating block 21 is loaded with the maximum amount, that is, the upper buoyancy is adjusted to the maximum, and the adjusting knob 76 is screwed to a suitable state so that the provided downward pulling force can unfold the curtain; for the middle rectifier curtain, the adjusting knob 76 is screwed to a suitable state, and the detachable floating block 21 is loaded with an appropriate amount so that the downward pulling force and the upper buoyancy are balanced; for the bottom rectifier curtain, the adjusting knob 76 is screwed to the tightest state, that is, the downward pulling force is adjusted to the maximum, and the detachable floating block 21 is loaded with an appropriate amount so that the upper buoyancy can unfold the curtain. Each counterweight block 7 is connected to each other through the counterweight block rope connection hole 72 according to the laying distance using a connecting rope, and the end of the connecting rope is tied to the river bank for fixing. Use another connecting rope to connect each waterproof curtain 1 to each other through the connecting lock hole 4 at the top of the curtain according to the laying distance, and the end of the connecting rope is tied to the river bank for fixing. Sink the counterweight block 7 to the bottom of the water, and slowly lower the waterproof curtain 1. After the underwater part of the curtain has completely entered the water body, the counterweight block 7 and the detachable floating block 21 and the embedded fixed floating block 22 respectively provide downward gravity and upward buoyancy to keep the waterproof curtain 1 always in a vertical state. When the laying plan changes and the rectifying curtain needs to be recovered, the waterproof curtain 1 can be pulled out of the water through the curtain connecting rope tied to the river bank, the connecting lock 6 is unlocked, and then the counterweight block 7 is pulled out of the water through another counterweight block connecting rope tied to the river bank. All parts of the systematic rectifying curtain can be recovered without causing pollution to the original environment.

[0033] like Figure 3 As shown, as a preferred embodiment 2, the top thread of the water-blocking curtain 1 is matched with a plurality of clamping screws 8, and the ends of the clamping screws 8 penetrate into the mounting holes 12 to form a clamping and fixing fit with the detachable floating block 21. The detachable floating block 21 is further fixed to prevent it from being washed away by the water flow.

[0034] like Figure 6 As shown, as a preferred embodiment 3, a method for preventing and controlling algal blooms, using the above-mentioned systematic rectifying curtain to adjust the water flow to prevent and control algal blooms, includes the following steps: S1. Collect model boundary data, including inflow and outflow or water level, meteorological conditions, topographic data, flow velocity and water temperature, divide the model calculation grid, and synchronously monitor the flow and water environment of the modeled water area; S2. Determine the initial and boundary conditions of the model based on the data collected in S1, solve the main parameters using the finite difference method based on the CE-QUAL-W2 model, construct a numerical model of river hydrodynamics, and perform model calibration and verification; S3, set different numerical simulation conditions, change the position, number and depth of the rectifier curtain, use the internal weir module of the model in S2 to simulate the rectifier curtain, output the simulation results of each condition, and analyze the impact on water temperature stratification and flow velocity; S4. Select the working conditions that can most significantly improve the water flow characteristics and install the systematic rectification curtain.

[0035] As a preferred embodiment 4, S1, collects model boundary data, mainly including terrain data, upstream inflow water temperature, flow, meteorological conditions (temperature, humidity, wind speed, wind direction, radiation), downstream vertical water temperature and water level. The flow field and water environment of the modeled water area are monitored synchronously. According to the river section terrain data, the actual monitoring area is divided into calculation grids in a rectangular format, divided into several unit segments vertically, and divided into several layers vertically. The width of each unit adopts the average width of the section. The calculation grid is mainly established by the following four parameters: (1) longitudinal spacing (DLX); (2) vertical spacing (DZ); (3) unit width (Width of Segment); (4) water surface slope (Slope). The grid unit length is between 0.1-10.0 km, and the vertical spacing is between 0.2-5.0 m. Among them, the width of the boundary grid cells is set to 0 to characterize the interconnection relationship between the tributaries. This type of grid does not participate in the actual operation of the model. The model grid is established as follows Figure 7 shown.

[0036] S2, determine the initial conditions and boundary conditions of the model. The given initial conditions include the start and end time, water body type, inflow, outflow, water volume, flow rate and water temperature. Assume that the initial water level remains unchanged along the way; the initial flow rate of the model is set to zero, the inflow conditions are mainly the upstream flow rate and the water temperature of the inflow, the water volume of the upper section of the dam is controlled by the inflow and outflow flow, and the water volume of the lower section of the dam is characterized by the water level. The water body type is fresh water, and the initial water temperature of the model is set to 30℃ (the average value observed in mid-August in summer).

[0037] In this embodiment, the model boundary conditions include upstream and downstream inflows and outflows, water surface boundaries, and riverbed bottom boundaries: a. The upper boundary of the model includes upstream inflow, tributary inflow, distributed tributary inflow, precipitation, and internal inflow. This embodiment mainly considers the upstream inflow part; b. The lower boundary of the model is controlled by water level and profile water temperature; c. The boundary conditions of the water surface include surface heat exchange, solar radiation absorption, wind stress, and gas exchange. The factors that affect the surface heat exchange amount mainly include the longitude and latitude of the calculated water area, air temperature, dew point temperature, wind speed and direction, and cloud coverage. In this embodiment, the longitude and latitude, air temperature, wind speed and direction are measured data, the dew point temperature is converted from the measured air temperature and relative humidity, and the cloud cover is calculated from the actual recorded sunshine hours and the theoretical sunshine hours of the local day. The input time interval is 1 hour.

[0038] d. A no-slip boundary is used at the bottom of the riverbed, that is, the normal boundary and tangential velocity of the riverbed are both zero, and the heat exchange between the riverbed and the reservoir water body is ignored.

[0039] According to the given initial conditions and boundary conditions, the hydrodynamic and water temperature model of the river section is constructed based on the CE-QUAL-W2 model, and the finite difference method is used to solve it. The model data is calibrated and verified, and the main control parameters of the model are finally selected as shown in Table 1. The model in this embodiment calculates the water balance mainly considering the volume balance, mass balance and energy balance, without considering precipitation and evaporation; the solution method of the water transport equation is ULTIMATE, and the weight coefficient of vertical convection is 0.55; the meteorological data is automatically interpolated according to the measured data of the hydrological station; the incoming flow automatically flows into the water body with similar density.

[0040] Table 1

[0041] The model verification uses the measured flow velocity, water temperature and simulated flow velocity and water temperature of important sections for comparison, such as Figure 8 As shown in the figure, the error between the measured flow velocity and the simulated flow velocity is within 0.2 m / s, and the error between the measured water temperature and the simulated water temperature is within 0.5℃, indicating that the model can better invert the flow field results and water temperature changes of the monitored river section.

[0042] S3, set different numerical simulation conditions to change the position, number and depth of the rectifier curtain. Use the internal weir module in the model to simulate the rectifier curtain, and parameterize the internal weir module according to the curtain design properties of different conditions, that is, in the same time period, some cells (units) of the seg (defined segment) where the rectifier curtain is located are water-blocking rock mass. Input the parameters of each simulation condition into the model, simulate the impact of the rectifier curtain on the water temperature stratification and flow velocity before and after the rectifier curtain is laid, and output the simulation results. The simulation results of some conditions are shown in the figure. Fig. 9 shown.

[0043] Depend on Fig. 9 The simulation results of some working conditions shown in the figure show that: Under the condition without a rectifying curtain (a), there is an obvious stratified anisotropic flow near the monitoring section. The water temperature of the upstream flow is relatively low, and it flows out of the reservoir bay in the form of a bottom-level downslope density flow; the water body that flows back into the reservoir bay from the downstream flows from the middle layer to the upstream, and the surface water body flows from the upstream to the downstream. On the whole, the water body of the reservoir bay forms two circulation processes, and the flow velocity in the backwater area is generally small, within 0.05m / s. The water temperature in the backwater area is obviously stratified, and the temperature difference between the surface and the bottom of the monitoring section reaches about 5℃. The thermocline appears near the interface of the stratified flow.

[0044] When a surface straightening curtain is deployed 500 m downstream of the monitoring section (b), a local circulation is formed in the upper water body. The local mixing in the strong circulation area is strong, the flow velocity is large, and the thickness of the surface high-temperature water layer becomes thinner. However, the scope of influence on the water flow field is small, and the water temperature in the middle and lower layers does not change significantly.

[0045] Under the condition of laying a bottom straightening curtain 300 m upstream of the monitoring section (c), after the upstream low-temperature flow reaches the bottom straightening curtain, the low-temperature water is blocked by the straightening curtain and forms a circulation on the upper side of the curtain. The cross-sectional flow velocity increases significantly, and vertical mixing is enhanced. The flow velocity of the downstream surface water increases, and multiple circulations are formed in the lower water body.

[0046] When the straightening curtains are deployed simultaneously at the bottom layer 300 m upstream and at the surface layer 500 m downstream of the monitoring section (d), the vertical mixing of the water body is intensified, the water temperature stratification is weakened, the surface water temperature is reduced, and the circulation pattern and water temperature stratification at the monitoring section change significantly.

[0047] S4, select the working conditions that have the most obvious effect on improving water flow characteristics, and install the systematic rectification curtain. After a period of actual installation, evaluate the installation effect of the systematic rectification curtain, including but not limited to Fig.10 Monitor the changes in horizontal flow velocity in the section near the upstream and downstream. Fig.11 Monitor the changes in water temperature stratification near the section. Fig.12 Monitor the changes in pH stratification near the section.

[0048] In this embodiment, the flow field and water environment of the nearby waters were monitored before and after the installation of the systematic straightening curtain. The results showed that the monitoring sections 300m upstream and 500m downstream showed stratified anisotropic flow before and after the installation of the straightening curtain, that is, the upper water body flowed upstream and the lower water body flowed downstream. In comparison, after the installation of the straightening curtain, the bottom flow velocity decreased, the middle layer did not change much, but the upper water body flow velocity increased, and the flow velocity of the backflow water body flowing upstream increased to 0.02 m / s. Fig.10 shown.

[0049] The overall range of water temperature near the monitoring section is between 26.5-34.8℃, and the pH fluctuates between 6.9-10.3. The overall performance is that the pH of the surface layer is higher than that of the bottom layer. Combined with the analysis of water temperature changes, it can be seen that the pH change of this section is significantly positively correlated with the water temperature. The increase in water temperature will contribute to the outbreak of cyanobacteria, and then promote the pH of the water body from neutral to alkaline. After the rectifier curtain was deployed, the water temperature stratification was weakened, and the water mixing was enhanced, which significantly reduced the pH of the upper water body to below 9.5, indicating that the pH of the water body can be effectively improved by changing the flow state and stratification intensity of the water body. Figure 11-12 shown.

[0050] In general, after the installation of the straightening curtain, the downstream density flow at the upstream bottom is blocked, cold water accumulates at the bottom, and a circulation is formed, which strengthens the vertical mixing of the water body, which is conducive to slowing down the growth of algae and reducing the pH of the water body. The present invention provides a systematic straightening curtain and a method for preventing and controlling water blooms, with an easily detachable split straightening curtain as the core, and the river hydrodynamic numerical model determines the layout position. The counterweight block with an automatic rope collection system and adjustable center of gravity is used to adapt to large water level fluctuations and different river bottom terrains, overcoming the difficulties of the straightening curtain, such as difficulty in positioning, narrow scope of application, non-reusability, cost and transportation.

Claims

1. A systematic rectifying curtain, characterized in that: The invention comprises a plurality of curtain units, wherein the curtain units are detachably connected to each other, and each of the curtain units comprises a waterproof curtain (1). The top of the waterproof curtain (1) is detachably provided with a plurality of floating blocks (2). A curtain connection lock hole (4) is provided at the bottom side of the middle position of the waterproof curtain (1). The curtain connection lock hole (4) at the bottom side is connected to a connection lock buckle (6) via a connection rope (5). The connection lock buckle (6) is connected to a counterweight mechanism (7) via another connection rope (5), and the connection rope (5) and the counterweight mechanism (7) form an elastic contraction fit via a coil spring (77).

2. A systematic rectifying curtain according to claim 1, characterized in that: Magnets (3) are fixedly provided on both sides of the waterproof curtain (1), and the magnets (3) are symmetrically arranged with respect to the bottom curtain connection lock holes (4), so that the waterproof curtains (1) of adjacent curtain units are fixedly engaged by magnetic attraction through the magnets (3).

3. A systematic rectifying curtain according to claim 2, characterized in that: The floating blocks (2) include a plurality of detachable floating blocks (21) and embedded fixed floating blocks (22); the top of the waterproof curtain (1) is provided with a fixing hole (11) and a mounting hole (12), respectively; the fixing holes (11) are each snap-fitted and fixedly mounted with a corresponding embedded fixed floating block (22); and the mounting holes (12) are snap-fitted and fixedly mounted with a plurality of detachable floating blocks (21) in a detachable manner.

4. A systematic rectifying curtain according to claim 3, characterized in that: A curtain connection lock hole (4) is provided on the top side of the middle position of the waterproof curtain (1), two fixing holes (11) are provided, and the fixing holes (11) are located on both sides of the top curtain connection lock hole (4) and are symmetrically arranged about the top curtain connection lock hole (4), and the installation hole (12) is located on the top of the curtain connection lock hole (4), and the middle position of the installation hole (12) coincides with the middle position of the waterproof curtain (1).

5. A systematic rectifying curtain according to claim 4, characterized in that: The top thread of the water-blocking curtain (1) is engaged with a plurality of clamping screws (8), and the ends of the clamping screws (8) penetrate into the mounting holes (12) to form a clamping and fixing engagement with the detachable floating blocks (21).

6. A systematic rectifying curtain according to claim 4, characterized in that: The counterweight mechanism (7) comprises a capsule-shaped counterweight outer shell (71), a mounting cavity is provided in the middle of the counterweight outer shell (71), a winding disk (75) is provided in the mounting cavity, one end of a coil spring (77) is connected to the winding disk (75) and is tightened on the winding disk (75), and a connecting rope (5) passes through the counterweight outer shell (71) and is connected to the other end of the coil spring (77) through a cleaning brush (74) and a rope stopper (73) in sequence to form an elastic scroll fit. The cleaning brush (74) forms a blocking fit with the debris outside the shell, the rope limit block (73) forms a limit fit with the connecting rope (5), an adjusting knob (76) is provided on one side of the counterweight block outer shell (71), and the adjusting knob (76) forms a linkage fit with the winding disk (75), a counterweight iron block (78) is provided inside the counterweight block outer shell (71) at the bottom of the installation cavity, and the rest of the counterweight block outer shell (71) outside the installation cavity is filled with counterweight filling material (79).

7. A systematic rectifying curtain according to claim 6, characterized in that: Counterweight block rope connection holes (72) are provided on both sides of the counterweight block outer shell (71), and the counterweight block rope connection holes (72) penetrate the counterweight filling material (79), and the counterweight block rope connection holes (72) are symmetrically arranged with respect to the installation cavity.

8. A method for preventing and controlling algal blooms, characterized in that: Using a systematic rectifying curtain as described in any one of claims 1 to 7 to adjust water flow to prevent and control algal blooms comprises the following steps: S1. Collect model boundary data, including inflow and outflow or water level, meteorological conditions, topographic data, flow velocity and water temperature, divide the model calculation grid, and synchronously monitor the flow and water environment of the modeled water area; S2. Determine the initial and boundary conditions of the model based on the data collected in S1, solve the main parameters using the finite difference method based on the CE-QUAL-W2 model, construct a numerical model of river hydrodynamics, and perform model calibration and verification; S3, set different numerical simulation conditions, change the position, number and depth of the rectifier curtain, use the internal weir module of the model in S2 to simulate the rectifier curtain, output the simulation results of each condition, and analyze the impact on water temperature stratification and flow velocity; S4. Select the working conditions that can most significantly improve the water flow characteristics and install the systematic rectification curtain.

9. A method for preventing and controlling water blooms according to claim 8, characterized in that: The initial conditions in S2 include that the initial water level remains unchanged along the way, the initial flow velocity of the model is set to zero, the inflow conditions are mainly the upstream flow rate and the inflow water temperature, the water volume in the upper section of the dam is controlled by the inflow and outflow flow, the water volume in the lower section of the dam is characterized by the water level, the water body type is fresh water, and the initial water temperature of the model is set to the observed average value; The boundary conditions in S2 include upstream and downstream inflows and outflows, the water surface boundary, and the riverbed bottom boundary.

10. A method for preventing and controlling water blooms according to claim 9, characterized in that: The working conditions of S3 include the working condition of no straightening curtain, the working condition of laying a surface straightening curtain 500m downstream of the monitoring section, the working condition of laying a bottom straightening curtain 300m upstream of the monitoring section, and the working condition of laying straightening curtains at the bottom layer 300m upstream of the monitoring section and the surface layer 500m downstream at the same time.

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