Seawater desalination treatment device

Abstract

The invention relates to a seawater desalination treatment device, and relates to the technical field of seawater desalination, the seawater desalination treatment device comprises a base, a seawater storage pool used for storing seawater is arranged below the base, a seawater conveying device is fixed on the base, a fresh water storage pool is arranged on one side of the seawater storage pool, and the fresh water storage pool is arranged on the other side of the seawater storage pool. A seawater treatment assembly is arranged between the seawater storage pool and the fresh water storage pool and comprises a seawater gathering box, a plurality of seawater permeation pipes are installed on the seawater gathering box, the seawater permeation pipes are bent in an S shape and placed in the fresh water storage pool, and the seawater permeation pipes are used for extracting fresh water from seawater. A water control valve is arranged at one end, far away from the seawater conveying device, of the seawater permeation pipe, and is used for controlling the water flow, so that pressure difference is generated in the seawater permeation pipe, and high-concentration saline water after fresh water extraction is discharged; a fresh water conveying pipe is mounted on the fresh water storage pool. The system has the effects that the dependence of a traditional system on continuous external energy is reduced, and the overall energy consumption is reduced.

Description

Technical Field

[0001] This application relates to the field of seawater desalination technology, and in particular to a seawater desalination treatment device. Background Technology

[0002] Seawater desalination technology, as an important means of solving the global water shortage problem, has been widely used in coastal areas and islands around the world. Current mainstream technologies include reverse osmosis, multi-stage flash evaporation, and electrodialysis, with reverse osmosis holding a dominant position due to its high desalination rate and relatively mature process. Existing reverse osmosis seawater desalination systems typically consist of a pretreatment unit, a high-pressure pump, reverse osmosis membrane modules, and a post-treatment unit. Its core function is to pressurize seawater to 5-7 MPa using an external high-pressure pump, forcing water molecules to pass through a semi-permeable membrane into the freshwater side, while salt and impurities are retained to form concentrated brine. This technology removes suspended solids through multi-stage filtration pretreatment, utilizes the high-pressure pump to provide the osmosis driving force, and employs spiral-wound or hollow fiber reverse osmosis membrane modules to achieve brine separation. Finally, after post-treatment to adjust the water quality, freshwater is output. The system operation relies on a stable power supply to maintain the high-pressure environment, and the various units are integrated through pipelines and valves to achieve continuous production.

[0003] However, in existing technologies, the seawater desalination process often requires a continuous external energy input to maintain a high-pressure environment, resulting in high overall system energy consumption and complex equipment structure.

[0004] Traditional seawater desalination technologies largely rely on high-pressure pump-driven reverse osmosis systems, which are energy-intensive, have large equipment sizes, and are complex to operate and maintain. Especially in off-grid islands and emergency water supply scenarios, they suffer from strong dependence on power supply, demanding installation conditions, and unstable brine discharge control. In existing systems, the membrane modules are often arranged in a linear fashion, limiting the effective permeation area; pressure differential formation largely depends on external pressurization, making adaptive flow regulation difficult; and backmixing easily occurs at the interface between concentrated brine and freshwater, affecting the stability of the product water quality. These problems result in large fluctuations in desalination efficiency, poor system robustness, and persistently high long-term operating costs. Summary of the Invention

[0005] The purpose of this application is to provide a seawater desalination device to solve the above-mentioned technical problems.

[0006] The seawater desalination device provided in this application adopts the following technical solution: A seawater desalination device includes a base, a seawater storage tank for storing seawater is arranged below the base, a seawater conveying device is fixed on the base, a freshwater storage tank is arranged on one side of the seawater storage tank, and a seawater treatment component is arranged between the seawater storage tank and the freshwater storage tank. The seawater treatment component includes a seawater collection tank, a plurality of seawater permeation pipes are installed on the seawater collection tank, the seawater permeation pipes are S-shaped and placed in the freshwater storage tank, the seawater permeation pipes are used to extract freshwater from seawater, a water control valve is arranged at the end of the seawater permeation pipe away from the seawater conveying device, the water control valve is used to control the water flow, so as to generate a pressure difference in the seawater permeation pipe and discharge the high-concentration brine after the freshwater is extracted; a freshwater conveying pipe is installed on the freshwater storage tank.

[0007] Optionally, the seawater conveying device includes multiple water intake cylinders fixed on a base. A piston block is installed inside each water intake cylinder, and a traction rod is installed on the piston block. A torque rod is hinged to the traction rod. A water conveying support frame is fixed on the base and is hinged to the torque rod. A float is hinged to the end of the torque rod away from the water intake cylinder, and a counterweight is fixed to the float, which floats on the sea surface. An inlet check valve is fixed to the lower end of each water intake cylinder, and an outlet check valve is fixed to the side of each water intake cylinder. An inlet pipe is installed on the inlet check valve and is inserted into a seawater storage tank. An outlet pipe is installed on the outlet check valve and is connected to a seawater collection tank.

[0008] Optionally, the water intake cylinder is symmetrically arranged on both sides of the water conveyance support frame, and the torque rod controls the up and down movement of a pair of traction rods.

[0009] Optionally, a booster pump is installed on the base, the booster pump is equipped with a water pumping pipe, the booster pump is equipped with a water delivery pipe, the water pumping pipe is connected to the seawater collection tank, and the water delivery pipe is connected to the seawater collection tank.

[0010] Optionally, the seawater storage tank is buried in the sand. A seawater filtration zone is set on the side of the seawater storage tank closest to the sea. The seawater filtration zone is arranged from the outside to the inside as a coarse filtration zone, an adsorption zone, and an ultrafiltration zone. The coarse filtration zone is used to filter plankton in the seawater. The adsorption zone is filled with activated carbon to adsorb organic matter in the seawater. The ultrafiltration zone is equipped with an ultrafiltration membrane to filter fine impurities in the seawater.

[0011] Optionally, a pipe support frame is provided in the freshwater storage tank to support the seawater infiltration pipe, so that the seawater infiltration pipe is placed in the freshwater storage tank in an S-shape.

[0012] Optionally, the seawater permeation pipe includes a cotton wadding layer, an RO reverse osmosis layer is disposed on the outside of the cotton wadding layer, a support structure is disposed on the outside of the RO reverse osmosis layer, the support structure is used to make the RO reverse osmosis layer into a pleated structure, a sintered PE layer is disposed on the outside of the support structure, and a braided protective layer is disposed on the outside of the sintered PE layer; the cotton wadding layer is used to adsorb impurities and salt in seawater and protect the RO reverse osmosis layer.

[0013] Optionally, the support structure is a spring, and the spring is a sheet-like structure; the cotton layer is detachably connected to the RO reverse osmosis layer, and a cotton locking device is installed inside the seawater permeation pipe.

[0014] Optionally, the cotton wadding locking component includes a first threaded cylinder sleeved on the outside of the braided protective layer, an expansion sleeve detachably installed inside the first threaded cylinder, a supporting threaded tube threadedly installed inside the expansion sleeve, a limiting protrusion provided on the outside of the expansion sleeve, a locking limiting groove cooperating with the limiting protrusion provided on the inside of the first threaded cylinder, and the first threaded cylinder connected to the seawater collection tank; an internal threaded sleeve is installed on the seawater collection tank, the first threaded cylinder is connected to the internal threaded sleeve, a sealing ring abutting against the first threaded cylinder is provided on the inside of the internal threaded sleeve, and a torsion groove is provided at the end of the supporting threaded tube; The expansion sleeve includes a central support section and expansion sections symmetrically arranged on both sides of the support section; the support threaded tubes are arranged at both ends of the expansion sleeve.

[0015] Optionally, the piston block includes a piston cylinder with multiple positioning grooves. A sealing ring is fitted onto each positioning groove, and a locking strip is provided inside the sealing ring. A side hole is provided on the piston cylinder, through which the locking strip passes. The locking strip is connected together by a sealing locking member, which includes an upper clamping plate and a lower clamping plate, and is connected together by bolts. A limit ring is installed on the upper clamping plate, and a rubber strip limit groove is provided on the limit ring for the locking strip to pass through. The lower clamping plate is installed inside the limit ring.

[0016] In summary, this application includes at least one of the following beneficial technical effects: 1. This application provides a seawater desalination treatment device. This solution ensures device stability by setting a base to support the overall structure; it facilitates continuous operation of subsequent treatment processes by setting a seawater storage tank below the base for temporary seawater storage; it achieves automatic seawater transport by fixing a seawater conveying device on the base; it forms a clear freshwater collection area by setting a freshwater storage tank on one side of the seawater storage tank; it integrates the core desalination function by setting a seawater treatment component between the seawater and freshwater storage tanks; the seawater treatment component includes a seawater collection tank for centralized distribution of seawater to be treated; and it improves desalination capacity by installing multiple seawater permeation pipes on the seawater collection tank. 2. The seawater permeation pipe is placed in a freshwater storage tank in an S-shape to extend the seawater flow path and increase the contact area. This pipe is used to extract freshwater from seawater, achieving the core function of brine separation. A control valve is installed at the end of the permeation pipe furthest from the seawater delivery device to regulate the outlet flow and create a pressure gradient within the pipe. This control valve regulates the water flow, creating a pressure difference within the permeation pipe and allowing the high-concentration brine after freshwater extraction to be discharged, eliminating the need for an external high-pressure pump to drive the reverse osmosis process. A freshwater delivery pipe is installed on the freshwater storage tank to ensure a stable output of desalinated freshwater. This design reduces the dependence of traditional systems on continuous external energy sources, lowering overall energy consumption. 3. The S-shaped arrangement of seawater permeation pipes effectively increases the membrane contact area per unit volume, enhancing desalination efficiency; the natural pressure difference mechanism formed by the water control valve simplifies the system structure and reduces maintenance requirements; the overall integrated design facilitates installation and on-site operation, significantly improving the practicality and economy of the seawater desalination unit. 4. A water control valve is installed at the end of the seawater infiltration pipe away from the seawater delivery device. The water control valve is used to control the water flow and create a pressure difference in the seawater infiltration pipe. The opening of the water control valve can be controlled according to the amount of seawater input from the seawater delivery device. When the water volume is sufficient, the water control valve can be opened wider, and when the seawater input is small, the opening of the water control valve can be closed smaller, so that the pressure in the seawater infiltration pipe remains constant and the fresh water is continuously and stably produced. 5. When the kinetic energy of the waves is sufficient, the water control valve can be fully opened to clean and discharge impurities in the seawater infiltration pipe, thereby facilitating the self-cleaning of the seawater treatment components and extending their service life. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the overall structure of an embodiment of this application; Figure 2 This is a schematic diagram of the internal structure of an embodiment of this application; Figure 3 This is a schematic diagram of the seawater conveying device according to an embodiment of this application; Figure 4This is a schematic diagram of the seawater filtration zone structure according to an embodiment of this application; Figure 5 This is a schematic diagram of the seawater permeation pipe structure according to an embodiment of this application; Figure 6 This is an embodiment of the present application. Figure 5 A magnified view of the structure at point A in the middle; Figure 7 This is a schematic diagram of the cotton wadding locking component structure in an embodiment of this application; Figure 8 This is a schematic diagram of the piston block structure according to an embodiment of this application; Figure 9 This is a schematic diagram of the sealing and locking component structure in an embodiment of this application.

[0018] In the diagram, 1. Base; 2. Seawater storage tank; 21. Seawater filtration zone; 22. Coarse filtration zone; 23. Adsorption zone; 24. Ultrafiltration zone; 3. Seawater conveying device; 31. Water intake cylinder; 32. Piston block; 321. Piston cylinder; 322. Positioning groove; 323. Sealing ring; 324. Locking strip; 325. Side hole; 326. Sealing and locking component; 3261. Upper clamping plate; 3262. Lower clamping plate; 3263. Limiting ring; 3264. Limiting groove; 33. Traction rod; 34. Torque rod; 35. Water conveying support frame; 36. Float; 37. Counterweight; 38. Inlet check valve; 39. Outlet check valve; 310. 1. Inlet pipe; 3. Outlet pipe; 4. Freshwater storage tank; 4. Pipe support frame; 5. Seawater treatment components; 5. Seawater collection tank; 5. Seawater permeation pipe; 5. Cotton layer; 5. RO reverse osmosis layer; 5. Support structure; 5. sintered PE layer; 5. woven protective layer; 5. Wool locking component; 5. First threaded cylinder; 5. Expansion sleeve; 5. Support threaded pipe; 5. Limiting protrusion; 5. Locking limiting groove; 5. Torsion groove; 5. Water control valve; 6. Booster pump; 6. Pumping pipe; 6. Water delivery pipe; 7. Freshwater delivery pipe. Detailed Implementation

[0019] The following is in conjunction with the appendix Figure 1 -Appendix Figure 9 This application will be described in further detail below.

[0020] Reference Figure 1 , Figure 2 , Figure 3This application proposes a seawater desalination device, including a base 1, a seawater storage tank 2 for storing seawater disposed below the base 1, a seawater conveying device 3 fixed on the base 1, a freshwater storage tank 4 disposed on one side of the seawater storage tank 2, and a seawater treatment component 5 disposed between the seawater storage tank 2 and the freshwater storage tank 4. The seawater treatment component 5 includes a seawater collection tank 51, on which multiple seawater permeation pipes 52 are installed. The seawater permeation pipes 52 are S-shaped and placed in the freshwater storage tank 4. The seawater permeation pipes 52 are used to extract freshwater from seawater. A water control valve 53 is disposed at the end of the seawater permeation pipe 52 away from the seawater conveying device 3. The water control valve 53 is used to control the water flow, so as to generate a pressure difference in the seawater permeation pipe 52 and discharge the high-concentration brine after the freshwater is extracted. A freshwater conveying pipe 7 is installed on the freshwater storage tank 4.

[0021] This embodiment provides a seawater desalination device that is structurally integrated, energy-efficient, space-efficient, and stable in operation. Its core lies in constructing a passive differential pressure generation mechanism based on the synergistic effect of gravitational potential energy and throttling control, and enhancing the permeation mass transfer process through geometric configuration optimization. The entire device relies on a base 1 for modular support and functional integration. The components are arranged according to material flow direction and functional logic hierarchy: seawater undergoes temporary storage, transportation, aggregation, selective permeation, freshwater collection, and concentrate separation, forming a closed-loop, controllable desalination path. Among them, the seawater storage tank 2 serves as a front-end buffer unit, providing a foundation for subsequent stable liquid supply; the seawater conveying device 3 undertakes the power input function, continuously feeding seawater into the seawater collection tank 51, increasing the internal pressure of the seawater collection tank 51; the seawater treatment component 5 is the core desalination unit, with its internal seawater collection tank 51 serving as a pressure distribution chamber, evenly distributing the pressure to each seawater permeation pipe 52; the S-shaped curved arrangement of the seawater permeation pipe 52 not only prolongs the residence time of seawater at the permeation interface, but also suppresses concentration polarization through the local velocity gradient induced by curvature and boundary layer disturbance; the water control valve 53 is set at the far end of the seawater permeation pipe 52, forming a terminal throttling point, so that the entire seawater permeation pipe 52 forms a continuous pressure gradient from high pressure inside to low pressure outside, thereby driving water molecules to continuously permeate across the membrane without the need for an additional high-pressure pump; the freshwater storage tank 4 has the dual function of receiving permeate and accommodating the space of the permeation pipes; and the freshwater conveying pipe 7 realizes the directional export of permeate.

[0022] The base 1 is a rigid load-bearing structure, with an overall rectangular frame shape and leveling feet at the bottom to adapt to uneven tidal flats or deck mounting surfaces; the surface is treated with epoxy zinc-rich anti-corrosion coating. This base not only supports all the upper components but also constrains the relative displacement between the seawater conveying device 3 and the seawater treatment component 5 through structural rigidity, ensuring connection sealing and synchronized movement. The seawater storage tank 2 is located directly below the base 1 and is a semi-buried rectangular concrete reservoir, with approximately 60% of its volume buried in the sand to utilize geothermal heat to stabilize the seawater temperature and reduce evaporation loss; the side wall of the tank, closer to the sea, has an inlet that connects to the seawater filtration zone 21; this structure allows the seawater storage tank 2 to perform temporary storage, flow stabilization, and preliminary sedimentation functions.

[0023] The seawater conveying device 3 is fixed to the base 1, and its function is to stably transport seawater from the seawater storage tank 2 to the seawater collection tank 51. This device does not rely on electric power, but utilizes the energy of sea surface waves—the float 36 rises and falls with the waves, and is converted into the reciprocating motion of the piston block 32 within the water intake cylinder 31 via the torque rod 34 and the traction rod 33, achieving volumetric suction and pressure delivery. This mechanical energy conversion structure significantly reduces dependence on the power grid or generator.

[0024] The freshwater storage tank 4 is located on one side of the seawater storage tank 2, and is arranged horizontally alongside the two. The tank body is a sealed stainless steel box, and the top is equipped with a maintenance manhole and a liquid level sensor interface. In addition to holding freshwater, its inner cavity also provides a submersible installation space for the seawater infiltration pipe 52.

[0025] This layout maintains a near-constant static pressure on the freshwater side, which is beneficial for maintaining a stable osmotic pressure difference. In an alternative embodiment, the freshwater storage tank 4 can be designed as a multi-stage stepped partitioned chamber, with each stage connected by an overflow weir, to achieve gravity-fed graded storage of produced water and homogenization of water quality; or it can be made of transparent acrylic material to create an observation window structure, which facilitates real-time monitoring of the scaling status on the surface of the seawater infiltration pipe 52.

[0026] The seawater treatment component 5 is the core functional module for realizing the seawater-freshwater phase change, consisting of a seawater collection tank 51 and multiple seawater infiltration pipes 52. The seawater collection tank 51 is a pressure-resistant stainless steel cavity with a main inlet and multiple branch interfaces; its function is to rectify the unsteady water flow from the seawater conveying device 3 into a uniform, low-pulsation distribution flow, ensuring that the inlet pressure of each seawater infiltration pipe 52 is consistent.

[0027] Seawater infiltration pipe 52 is installed at the branch interface of seawater collection tank 51, and is arranged in an S-shape within freshwater storage tank 4. This S-shape configuration refers to a single pipe having at least two reverse curvature segments (i.e., a sinusoidal half-wave or Euler spiral segment) in the horizontal plane. This arrangement maximizes the effective membrane area within the limited tank space, while simultaneously generating Dean vortices in the curved sections, enhancing membrane surface shear and delaying pollutant deposition.

[0028] The water control valve 53 is located at the end of the seawater permeation pipe 52 furthest from the seawater delivery device 3, i.e., the tail end of the pipe inside the freshwater storage tank 4. This valve is a manual precision throttling valve with a ceramic hard-seal structure for the valve core, providing a locking and positioning function. Its core function is to precisely limit the outlet flow area, establishing and maintaining a pressure drop along the entire seawater permeation pipe 52. The inlet pressure is provided by the static pressure head of the seawater collection tank 51 and the delivery kinetic energy, and the outlet pressure approaches the static pressure of the liquid surface in the freshwater storage tank 4. This creates an effective net driving pressure (NDP) on both sides of the RO reverse osmosis layer 522, driving water molecules to selectively permeate.

[0029] In an alternative embodiment, the water control valve 53 can be replaced with an electric proportional regulating valve, which is connected to a PLC control system and dynamically adjusts the opening based on feedback from an online conductivity meter to achieve constant control of concentrate salinity; or a fixed orifice plate flow limiter can be used in conjunction with replaceable orifice gaskets to achieve graded adjustment.

[0030] The freshwater delivery pipe 7 is installed on the upper side wall of the freshwater storage tank 4, with the pipe opening below the liquid level. It is made of stainless steel corrugated pipe, and the end can be connected to the user's water terminal or a secondary booster pump. Its position design ensures that only the surface low-salinity freshwater is extracted, avoiding disturbance to the trace concentrated water settling zone that may exist at the bottom.

[0031] The aforementioned components are tightly coupled through physical positional relationships and fluid communication: the seawater storage tank 2 supplies liquid to the intake cylinder 31 via the inlet pipe 310; the intake cylinder 31 sends pressurized seawater into the seawater collection tank 51 via the outlet pipe 311; the seawater collection tank 51 supplies water evenly to each seawater permeation pipe 52 via branch interfaces; the seawater permeation pipe 52 forms a pressure difference under the throttling action of the control valve 53, driving freshwater through the membrane layer into the freshwater storage tank 4; concentrated brine is collected along the inner wall of the seawater permeation pipe 52 towards the control valve 53 and discharged. The S-shaped curved structure allows the same seawater permeation pipe 52 to occupy a larger three-dimensional space in the freshwater storage tank 4, avoiding pipe shading and ensuring that each section of the curved pipe is in a different flow field environment, thus improving the overall mass transfer uniformity; the end setting of the control valve 53 ensures that the pressure gradient direction is consistent with the permeation direction (from inside the pipe to outside, from the high-salt side to the low-salt side), which conforms to the basic mass transfer law of reverse osmosis and significantly improves the permeate flux per unit membrane area.

[0032] Through the above technical solutions, this application achieves the following: a stable osmotic pressure differential is constructed by utilizing the mechanical energy of sea surface fluctuations and terminal throttling without configuring a main high-pressure pump; the effective utilization area and anti-fouling capability of the RO reverse osmosis layer 522 are improved through the spatial extension and flow field enhancement of the S-shaped seawater permeation pipe 52; and a gravity-driven natural flow and compact footprint are achieved based on the horizontal parallel layout of the base 1—seawater storage tank 2—freshwater storage tank 4. The continuous pressure drop formed by terminal throttling solves the problem of intensified local concentration polarization on the membrane surface under traditional constant pressure liquid supply; the enhanced turbulent mixing due to the S-shaped bend alleviates the decrease in permeate flux caused by the velocity decay at the end of the straight pipe; and the integrated layout of the base 1 avoids the pipeline redundancy and sealing failure risks caused by the dispersed installation of multiple devices—thus effectively solving the common problems mentioned in the background technology, such as high energy consumption, complex structure, and inconvenient maintenance, achieving the technical effects of low power consumption, high stability, and easy deployment.

[0033] Refer to Figure 2. Figure 3 The piston block 32 is a plunger-type component adapted to the inner cavity of the water intake cylinder 31. Its outer circumference is equipped with an elastic sealing structure to maintain the airtightness and liquid tightness of the cylinder during reciprocating motion. The traction rod 33 is a straight, rigid connecting rod made of aluminum alloy or glass fiber reinforced plastic (GFRP). One end is hinged to the piston block 32 via a pin, and the other end is hinged to the torque rod 34 via a pin. The length of the traction rod 33 is designed according to the lever ratio, so that the slight vertical displacement of the float 36 can be converted into the effective stroke of the piston block 32. The torque rod 34 is an equal-arm or unequal-arm lever structure made of high-strength carbon steel or titanium alloy. Its middle part is hinged to the top fulcrum of the water supply support frame 35 via a pin, forming a swing mechanism with this fulcrum as the center of rotation. The end closer to the water intake cylinder 31 is connected to the traction rod 33, and the end farther from the water intake cylinder 31 is connected to the float 36. The lever arm ratio of the torque rod 34 can be adjusted according to the tidal range characteristics: when the average wave height is less than 0.5... When the wave height is m, a long lever arm and short resistance arm design is adopted to amplify the displacement; when the wave height is greater than 0.8 m, an equal arm design can be adopted to suppress overshoot.

[0034] The water conveyance support frame 35 is a portal or A-shaped rigid support, fixed to the upper surface of the base 1. Its top is equipped with a hinge seat with a self-lubricating bearing to support the rotational movement of the torque rod 34. The support column can be embedded inside the base 1 or reinforced by reinforcing ribs to resist the alternating bending moment generated by the swaying of the float. As an optional structure, the bottom of the water conveyance support frame 35 can be equipped with leveling feet to adapt to uneven installation foundations.

[0035] Float 36 is a hollow, sealed float in the shape of a sphere, ellipsoid, or truncated cone. It is made of HDPE (high-density polyethylene) or polyurethane foam. Its total volume is designed according to Archimedes' principle, so that even when fully loaded with counterweight 37, 1 / 3 to 1 / 2 of its volume remains above the water surface, ensuring sensitive response to waves and resistance to capsizing. Float 36 is hinged to the end of torque rod 34 by a pin or universal joint to adapt to the impact of oblique waves.

[0036] The counterweight 37 is a high-density metal block made of lead or cast iron, fixed to both ends of the float 36. It is used to adjust the overall center of gravity, suppress high-frequency shaking, and prolong the low-frequency resonance period, so that the float 36 can effectively capture the energy of the waves. The counterweight 37 is installed by threaded embedding or riveting. As an adjustable implementation method, the counterweight 37 can be designed as a modular combination structure, and the dynamic counterweight adjustment on site can be achieved by adding or removing sub-modules.

[0037] Both the inlet check valve 38 and the outlet check valve 39 are spring-loaded check valves with EPDM rubber-coated 304 stainless steel skeletons as valve cores. The inlet check valve 38 is installed at the bottom of the water intake cylinder 31, controlling the unidirectional flow of seawater from the inlet pipe 310 into the cylinder. The outlet check valve 39 is installed at the bottom of the side wall of the water intake cylinder 31, controlling the unidirectional output of seawater from the cylinder through the outlet pipe 311. The opening and closing sequence of the two valves is determined by the position of the piston block 32: when the piston moves downward, the pressure inside the cylinder increases, the inlet check valve 38 closes, and the outlet check valve 39 opens; when the piston moves upward, a negative pressure is formed inside the cylinder, the inlet check valve 38 opens, and the outlet check valve 39 closes. As an alternative, the two check valves can also be replaced with reed valves or diaphragm valves to adapt to nearshore seawater conditions with high sediment content.

[0038] Both the inlet pipe 310 and the outlet pipe 311 are pressure-resistant rigid pipes with inner diameters matching the corresponding one-way valves. The lower end of the inlet pipe 310 extends to the lower part of the seawater storage tank 2, avoiding surface scum and bottom sediment. The end of the outlet pipe 311 extends below the liquid surface of the seawater collection tank 51 to prevent gas from entering and affecting subsequent permeation efficiency. Both pipes are equipped with detachable quick-connect fittings for easy maintenance and replacement.

[0039] The aforementioned components work in concert: when the waves rise the float 36, the torque rod 34 rotates counterclockwise around the fulcrum of the water supply support frame 35, pulling the traction rod 33 upward, causing the piston block 32 to move upward. This increases the volume of the water intake cylinder 31, creating negative pressure. The inlet check valve 38 opens, and the outlet check valve 39 closes, allowing seawater to be drawn into the cylinder through the inlet pipe 310. When the waves recede, the float 36 descends, the torque rod 34 rotates clockwise, and the traction rod 33 pushes down the piston block 32. The seawater in the water intake cylinder 31 is pressurized, the inlet check valve 38 closes, and the outlet check valve 39 opens, allowing seawater to be forced into the seawater collection tank 51 through the outlet pipe 311. This process repeats continuously with the waves, achieving automatic water supply without human intervention.

[0040] Through the above technical solution, this application achieves the following: using natural sea surface fluctuations as the driving force, the small-amplitude, low-frequency, and irregular wave motion is amplified and directionally converted into a large-stroke, quasi-periodic linear motion of the piston block 32 through the lever of the torque rod 34; in conjunction with the timing switching of the inlet check valve 38 and the outlet check valve 39, the seawater is ensured to be pumped unidirectionally and pulsatingly to the seawater collection tank 51; thereby solving the common problems of high equipment cost, high energy consumption, high operation and maintenance difficulty, and poor environmental adaptability of seawater conveying devices that rely on external power supply or complex hydraulic / pneumatic systems in the background technology, and achieving the technical effects of energy saving and environmental protection, reliable structure, flexible deployment, and long-term maintenance-free operation; As seawater is continuously injected into the seawater collection tank 51, the pressure inside the seawater collection tank 51 gradually increases, so that the seawater entering the seawater infiltration pipe 52 has sufficient pressure, and under the action of the water control valve 53, a pressure difference is generated, and fresh water can seep out of the seawater infiltration pipe 52.

[0041] The output seawater is intermittent, the pressure inside the seawater infiltration tube 52 changes periodically, and the water flow inside the seawater infiltration tube 52 is sometimes fast and sometimes slow, forming a pulsed water flow, which can effectively prevent substances in the seawater from forming sediments inside the seawater infiltration tube 52.

[0042] Water intake cylinders 31 are symmetrically arranged on both sides of water conveyance support frame 35, and torque rods 34 control a pair of traction rods 33 to move up and down.

[0043] This embodiment arranges the water intake cylinders 31 in a centrally symmetrical manner on both sides of the water conveying support frame 35, and drives a pair of traction rods 33 to move up and down in opposite directions synchronously by the same torque rod 34, forming a double-cylinder alternating mechanical water intake structure. Its core lies in using the lever principle to achieve mechanical coupling and action coordination between the left and right water intake units, thereby improving the overall stability, flow continuity and structural durability of the seawater conveying device 3.

[0044] The water intake cylinders 31 are symmetrically arranged on both sides of the water conveying support frame 35. This means that two or more sets of water intake cylinders 31 are symmetrically distributed along the longitudinal center plane of the water conveying support frame 35, with parallel axes, equal spacing, and consistent installation height. This symmetrical layout allows the lateral moments generated by the water intake cylinders 31 on the left and right sides to cancel each other out when subjected to force, preventing the base 1 from torsion or local stress concentration due to unilateral load. As an optional implementation, the number of water intake cylinders 31 is even, and they are arranged in a mirror symmetrical manner with the water conveying support frame 35 as the reference, in order to adapt to the effective suction head requirements under different tidal level fluctuations.

[0045] The torque rod 34 controls the up-and-down movement of a pair of traction rods 33. The torque rod 34 acts as a rigid lever component, with its middle part hinged to the water conveyance support frame 35 to form a fulcrum, and its two ends hinged to the traction rods 33 on the left and right sides respectively. When the float 36 moves with the rise and fall of the sea surface, it causes the torque rod 34 to rotate around the fulcrum, and its two ends generate vertical displacements in opposite directions with equal displacement amplitudes, thereby synchronously driving the traction rods 33 on both sides to move in opposite linear directions. This linkage mechanism ensures that the piston blocks 32 in the left and right water intake cylinders 31 alternately complete the water intake and discharge strokes, which significantly reduces the pulsation of the seawater flow output by the one-way valve 39. As an optional implementation, the torque bar 34 is made of hollow aluminum alloy profile with a rectangular or I-shaped cross section to balance rigidity and lightweight; its fulcrum position is adjustable, for example by setting multiple sets of hinge holes on the water conveying support frame 35, thereby fine-tuning the lever arm length ratio and optimizing force transmission efficiency and response sensitivity.

[0046] There are defined mechanical transmission relationships between the components: the vertical displacement of the float 36 is converted into the angular displacement of the torque rod 34 after being stabilized by the counterweight 37; the linear displacement at both ends of the torque rod 34 is directly transmitted to the traction rod 33 through the hinge structure, and then the traction rod 33 drives the piston block 32 to reciprocate within the water intake cylinder 31; the inlet check valve 38 and the outlet check valve 39 automatically open and close according to the direction of piston movement, jointly ensuring the reliability of the unidirectional fluid transport path. This structure does not rely on an external power source, but is driven entirely by tidal energy, and has inherent safety and low operation and maintenance costs.

[0047] Through the above technical solution, this application achieves the following: under the condition of no external energy input, the float 36 is driven to rise and fall by natural tidal fluctuations. Through the lever amplification and direction conversion effect of the torque rod 34, the symmetrically arranged water intake cylinders 31 form an alternating working mode with consistent pace and opposite phase. Since the water intake cylinders 31 are symmetrically arranged on both sides of the water conveyance support frame 35, the lateral resultant force of the system approaches zero, which significantly suppresses the shaking of the base 1 and the fatigue of the connecting parts. Since the torque rod 34 synchronously controls the up and down movement of a pair of traction rods 33, the suction and discharge processes of the left and right water intake cylinders 31 compensate for each other, making the seawater flow rate entering the seawater collection tank 51 more stable, reducing the osmotic pressure fluctuation caused by the instantaneous flow impact of the subsequent seawater treatment components 5, thereby alleviating the concentration polarization phenomenon of the RO reverse osmosis layer 522, extending the service life of the seawater permeation pipe 52, and improving the stability of freshwater production.

[0048] Reference Figure 2 , Figure 3 A booster pump 6 is installed on the base 1. The booster pump 6 is equipped with a water pumping pipe 61 and a water delivery pipe 62. The water pumping pipe 61 is connected to the seawater collection tank 51, and the water delivery pipe 62 is connected to the seawater collection tank 51.

[0049] The core of the technical solution involved in this embodiment lies in constructing a closed-loop pressure enhancement circuit by integrating a booster pump 6 on the base 1 to compensate for the decrease in reverse osmosis flux caused by insufficient natural driving pressure difference. This solution does not change the raw water flow path or water quality treatment logic, but only applies controllable and adjustable additional hydrostatic pressure within the system, thereby increasing the effective transmembrane pressure difference across the seawater permeation pipe 52 and enhancing freshwater production efficiency. Its technical effects are manifested in the following ways: even when the output of the wave-driven seawater delivery device 3 is unstable or the tide level is low, it can still maintain a stable working pressure within the seawater collection tank 51; at the same time, since both the pumping pipe 61 and the delivery pipe 62 are connected to the same seawater collection tank 51, a self-circulating pressurization structure is formed, avoiding the introduction of external water sources or the discharge of diluent, ensuring the system's closedness and consistency with the raw water concentration.

[0050] The booster pump 6 is a vertical multistage centrifugal pump equipped with a frequency converter to achieve coordinated pressure and flow regulation. This pump is not used to directly pump seawater into the seawater permeation pipes 52, but rather to repeatedly pump, pressurize, and reinject the seawater temporarily stored in the seawater collection tank 51, thereby raising the overall liquid pressure within the tank and evenly distributing it to the inlet ends of each seawater permeation pipe 52. This design avoids the risks of localized turbulence, membrane erosion, or seal failure that might occur if pressurization is applied only at the inlet end of the seawater permeation pipe 52, thus improving the system's operational reliability.

[0051] The suction pipe 61 and the delivery pipe 62 are connected to the pre-set interfaces on the side wall of the seawater collection tank 51. The interfaces are equipped with sealing rings and metal back rings to ensure no leakage. The suction inlet of the suction pipe 61 is located in the lower middle part of the seawater collection tank 51, at a certain distance from the bottom of the tank, to avoid deposited impurities; the outlet of the delivery pipe 62 is arranged in the upper part of the tank, so that the pressurized water is injected tangentially, creating slight disturbance to inhibit local salt enrichment, while preventing air bubbles from being carried into the seawater infiltration pipe 52.

[0052] The connection between the booster pump 6 and the seawater collection tank 51 forms a single-point bidirectional flow channel structure: that is, the pumping pipe 61 and the delivery pipe 62 are independently connected to the tank, and the two are not physically connected inside the tank, nor do they share the same opening. This layout allows the booster pump 6 to simultaneously perform the "pumping low-pressure zone - high-pressure zone" action during operation, creating a weak but stable vertical pressure gradient inside the tank, which is beneficial for seawater to continuously converge towards the bottom inlet section of the seawater permeation pipe 52 under the assistance of gravity. As an optional implementation, the booster pump 6 can also be replaced with a plunger-type positive displacement pump, which has higher displacement accuracy and is suitable for RO membrane modules that are sensitive to pressure fluctuations. The synergistic effect between the components is manifested as follows: the start-up, shutdown, and operating parameters of the booster pump 6 are controlled by the pressure sensor and PLC controller built into the seawater collection tank 51; when the pressure inside the tank is detected to be lower than a set threshold, such as 0.45 MPa, the controller starts the booster pump 6, which draws seawater from the tank through the pumping pipe 61, pressurizes it, and then reinjects it through the water supply pipe 62; the pump automatically stops after the pressure rises back to the target range. This closed-loop control logic ensures that the pressurization action fully responds to the intrinsic pressure state of the system, without relying on external tidal cycles or manual intervention, significantly improving the level of automation and environmental adaptability.

[0053] Reference Figure 3 , Figure 4 Through the above technical solution, this application achieves the following: without changing the basic structure and process flow direction, by simply adding a booster pump 6 to the base 1 and connecting its pumping pipe 61 and water delivery pipe 62 to the seawater collection tank 51, a compact, fast-responding, and energy-controllable auxiliary pressurization mechanism is constructed. Since the booster pump 6 implements internal circulation pressurization of the seawater collection tank 51, rather than directly boosting the external seawater or pressurizing the end of the seawater permeation pipe 52, it avoids additional water intake energy consumption and pipeline complexity, and ensures that the net pressure difference borne by the RO reverse osmosis layer 522 is always within the safe design range. Thus, even when the natural pressure difference fluctuates or is insufficient, the water production flux of the seawater permeation pipe 52 can still be stably maintained, solving the technical problem in the background technology that the desalination efficiency drops sharply and the water production is intermittently interrupted due to unstable driving energy, and achieving a low-power, easily integrated seawater desalination system pressure control effect.

[0054] Reference Figure 1 , Figure 4 The lower part of the seawater storage tank 2 is buried in the sand. The seawater storage tank 2 has a seawater filtration zone 21 on the side closest to the sea. The seawater filtration zone 21 has a coarse filtration zone 22, an adsorption zone 23 and an ultrafiltration zone 24 arranged sequentially from the outside to the inside. The coarse filtration zone 22 is used to filter plankton in the seawater. The adsorption zone 23 is filled with activated carbon to adsorb organic matter in the seawater. The ultrafiltration zone 24 is equipped with an ultrafiltration membrane to filter fine impurities in the seawater.

[0055] Seawater storage tank 2 adopts a semi-buried structure design, with its lower part entirely submerged in the natural sand layer, and its upper edge slightly higher than or level with the sand surface; this balances the natural infiltration efficiency of the sand layer, structural stability, and resistance to tidal erosion. The sand, as a natural porous medium, forms the first-level physical barrier, effectively trapping large particles of silt, algal aggregates, and some suspended debris, and utilizing the adsorption effect of the sand particles to initially reduce turbidity and the amount of microorganisms attached. Simultaneously, the buried structure provides the tank with good thermal inertia, reducing the impact of diurnal temperature differences on the flux stability of the subsequent infiltration process and preventing fluctuations in RO membrane permeate rate due to sudden changes in water temperature.

[0056] The seawater filtration zone 21 is a modular, embedded structure arranged perpendicularly to the seaward side wall of the seawater storage tank 2 in the direction of coastal water inflow. It has a rectangular cross-section, with a width equal to the corresponding side wall of the seawater storage tank 2, and a height covering the inlet elevation range of the tank. Its front opening directly faces the sea, and its rear end connects to the interior of the seawater storage tank 2. This filtration zone is divided into three functional sections from the outside in: a coarse filtration zone 22, an adsorption zone 23, and an ultrafiltration zone 24. These three sections are separated by microporous stainless steel partitions to ensure unidirectional, laminar, and uniform water flow through each functional section, avoiding short-circuiting or channeling.

[0057] The coarse filtration zone 22 is composed of multiple layers of stacked stainless steel grid mesh with an inclination angle of 15°–30°, tilting downwards towards the inside of the pool. This allows trapped plankton, aquatic plant fragments, and plastic particles to automatically slide down to the bottom sludge collection tank under gravity, requiring regular manual cleaning. This structure can also be replaced with a honeycomb coarse filter plate made of polypropylene (PP) injection molding, with hexagonal pores, which is corrosion-resistant and maintenance-free.

[0058] The adsorption zone 23 is a packed cavity filled with columnar activated carbon granules. The activated carbon is made of wood or coconut shell and is used to adsorb dissolved organic matter (such as humic acid and fulvic acid), residual chlorine, algal toxins and odor-causing substances (such as geosmin and dimethylisoborneol). This adsorption unit can be replaced with modified zeolite particles or mesoporous carbon materials loaded with iron oxides, which can enhance the synergistic removal of trace inorganic pollutants such as arsenic and fluorine while retaining the adsorption capacity of organic matter.

[0059] The ultrafiltration zone 24 houses a hollow fiber ultrafiltration membrane module made of polyvinylidene fluoride (PVDF) or polyethersulfone (PES) and operates in a cross-flow manner. The ultrafiltration membrane housing is made of UPVC and has independent backwashing and chemical cleaning interfaces. This structure can also be replaced with a flat-plate ceramic ultrafiltration membrane or an immersed polyvinyl chloride (PVC) curtain membrane to suit different installation spaces and maintenance conditions.

[0060] The functional zones are linearly connected: seawater naturally infiltrates from the beach and first enters the coarse filtration zone 22 for large particle solid phase separation; then it passes through the evenly distributed baffle channels into the adsorption zone 23 to achieve targeted enrichment of dissolved organic pollutants; finally, it flows into the ultrafiltration zone 24, where colloids, bacteria, viruses, and nano-sized particles are intercepted through a dual mechanism of sieving and surface adsorption. The three zones work together to form a gradient purification chain of "coarse interception - fine adsorption - fine interception," improving the quality of the seawater taken.

[0061] Through the above technical solutions, this application achieves the following: before seawater enters the core desalination unit, it completes physical-chemical-physical multi-mechanism pretreatment by relying on the coupling effect of the beach body and the three-stage filtration zone; because the seawater storage tank 2 is buried in the beach, it utilizes the natural pores of the sand layer to achieve primary filtration and temperature stabilization, reducing the adaptation pressure of subsequent equipment to high turbidity and high biological activity raw water; because the seawater filtration zone 21 is arranged from the outside to the inside in the order of coarse filtration-adsorption-ultrafiltration, it ensures the balanced load of each layer of filter media and avoids premature saturation of activated carbon or rapid fouling of ultrafiltration membrane; because the coarse filtration zone 22 adopts a cleanable grid structure, the adsorption zone 23 adopts high iodine value activated carbon, and the ultrafiltration zone 24 adopts a low-pressure hollow fiber membrane, the parameters of the three are matched and the redundancy design is reasonable, which together solves the technical problems in the background technology that the complex pollution of suspended solids, organic matter and microorganisms in seawater causes the seawater permeation pipe 52 to be easily blocked, the RO membrane life to be shortened, and the system to be frequently shut down for cleaning, thereby significantly extending the continuous operation cycle of the seawater permeation pipe 52 and the entire seawater treatment component 5, and reducing the frequency of operation and maintenance and the cost of consumable replacement.

[0062] Reference Figure 2 A pipe support frame 41 is installed in the freshwater storage tank 4. The pipe support frame 41 is used to support the seawater infiltration pipe 52, so that the seawater infiltration pipe 52 is placed in the freshwater storage tank 4 in an S-shape.

[0063] In this embodiment, a dedicated pipe support frame 41 is installed inside the freshwater storage tank 4 to achieve spatial positioning and morphological constraint of multiple seawater permeation pipes 52, ensuring their stable S-shaped bending layout and thus guaranteeing the hydrodynamic stability of the permeation process and the effective working area of ​​the membrane surface. This support structure does not participate in hydraulic transport or pressure regulation, but only undertakes mechanical support functions. It is a passive structural reinforcement method with the characteristics of simple structure, maintenance-free, corrosion resistance, and strong adaptability.

[0064] The pipe support frame 41 is a rigid support made of stainless steel or engineering plastic. It has a grid-like or segmented arc-shaped arrangement structure and is spaced along the length of the freshwater storage tank 4. Each support unit is equipped with an arc-shaped support groove that matches the outer diameter of the seawater infiltration pipe 52. The groove opening faces upward and has a limiting flange to prevent the pipe from sliding laterally. The bottom of the pipe support frame 41 is fixedly connected to the bottom or side wall of the freshwater storage tank 4 by bolts or pre-embedded anchors to ensure the overall resistance to water flow disturbance.

[0065] Reference Figure 2 As an optional implementation, the pipe support frame 41 can also be a flexible polymer elastic support with a built-in shape memory alloy skeleton in its support part. When affected by the weight of the seawater permeation pipe 52 and slight thermal expansion and contraction, it can generate adaptive micro-deformation and still maintain fluctuation within the S-shaped curvature radius, avoiding stress concentration that could lead to wrinkling failure of the RO reverse osmosis layer 522. This variant is particularly suitable for nearshore marine conditions with significant temperature differences.

[0066] The pipe support frame 41 and the seawater permeation pipe 52 have a non-rigid contact relationship. The inner surface of the support groove is covered with a silicone buffer layer, which reduces scratch damage to the braided protective layer 525 during installation and allows the seawater permeation pipe 52 to undergo slight axial expansion and contraction under pressure differential to release the accumulated stress of internal osmotic pressure. As another optional implementation, the support groove of the pipe support frame 41 can be replaced with an adjustable clamping assembly, including a pair of symmetrically arranged elastic clamp arms and a knob-type tension adjustment mechanism. The operator can change the clamp opening degree through an external adjustment knob to adapt to different batches of seawater permeation pipes 52, improving device compatibility and on-site assembly efficiency.

[0067] "Placing the seawater infiltration pipe 52 in an S-shape within the freshwater storage tank 4" means that each seawater infiltration pipe 52 has a continuous double-bend shape along its longitudinal direction within the freshwater storage tank 4, i.e., it has two arc-shaped bends with opposite directions, each with a bend center angle of 90°–120°. The two bends are connected by a straight transition section, and the overall projected outline is a standard S-shape. This S-shaped layout increases the total length of the seawater infiltration pipe 52 that can be accommodated per unit volume of the freshwater storage tank 4, while also forming a natural turbulence channel to delay the occurrence of concentration polarization on the freshwater side. As an optional implementation, the S-shape can also be replaced by a W-shape or a multi-wave arrangement, as long as the number of bends is ≥2, the adjacent bends are in opposite directions, and all bends are constrained by the corresponding support points of the pipe support frame 41, it falls within the protection scope of this embodiment.

[0068] The synergistic effect of various technical features is reflected in the following: the structural form, material selection, installation position and support method of the pipe support frame 41 jointly determine the spatial configuration stability of the seawater infiltration pipe 52; while the S-shaped placement form in turn constrains the mechanical load distribution path of the pipe support frame 41. The two form a closed-loop adaptation relationship of "form-structure": the pipe support frame 41 provides discrete support points, and the seawater infiltration pipe 52 hangs down and is shaped naturally between the support points according to its bending stiffness, without the need for additional binding or welding; this matching method avoids the end suspension and collapse caused by the traditional straight pipe arrangement, and also avoids the cleaning difficulties and biofilm growth risks brought about by the fully enclosed conduit trench.

[0069] Through the above technical solution, this application achieves the following: within the limited space of the freshwater storage tank 4, multi-point, flexible, and adaptive support is provided for the seawater permeation pipe 52 in a low-intervention, highly robust manner, ensuring its reliable maintenance of the S-shaped spatial layout. Due to the presence of the pipe support frame 41, the seawater permeation pipe 52 is less prone to local buckling, tangling, or wall adhesion during operation, thus ensuring the effective participation of the RO reverse osmosis layer 522 in the permeation process throughout its entire circumference. The S-shaped arrangement extends the permeation path and enhances the disturbance of the freshwater side flow field, slowing down the rate of salt accumulation on the membrane surface. Simultaneously, the regularized support structure facilitates the segmented disassembly and replacement of the seawater permeation pipe 52 during later maintenance, significantly improving the overall maintainability of the system. All of these effects are determined by the pipe support frame 41 and its direct interaction with the S-shaped placement, without relying on the coordinated intervention of other components such as the booster pump 6, water control valve 53, or float 36.

[0070] Reference Figure 5 , Figure 6 , Figure 7 The seawater permeation pipe 52 includes a cotton wadding layer 521, an RO reverse osmosis layer 522 is provided on the outside of the cotton wadding layer 521, a support structure 523 is provided on the outside of the RO reverse osmosis layer 522, the support structure 523 is used to make the RO reverse osmosis layer 522 into a pleated structure, a sintered PE layer 524 is provided on the outside of the support structure 523, and a braided protective layer 525 is provided on the outside of the sintered PE layer 524; the cotton wadding layer 521 is used to adsorb impurities and salt in seawater and protect the RO reverse osmosis layer 522.

[0071] In this embodiment, the seawater infiltration pipe 52 adopts a multi-composite structure design from the inside out, with an overall flexible tubular shape. It extends axially and is arranged in an S-shape within the freshwater storage tank 4. Its core lies in achieving a synergistic effect of pretreatment, main desalination, structural reinforcement, and physical protection through functional stratification. This structure not only ensures the stability and flux maintenance capacity of the RO reverse osmosis layer 522 during long-term operation but also significantly extends the service life of the entire pipe, making it particularly suitable for nearshore seawater conditions with fluctuating water pressure, high turbidity, or a high content of suspended solids.

[0072] The innermost filter medium, cotton wadding layer 521, is made of natural or modified cellulose fibers through hot pressing or needle punching. It possesses a hydrophilic surface and cation exchange groups, enabling efficient adsorption of colloidal particles, algal debris, some divalent metal ions, and free chlorine byproducts. Its physical form is a loose, porous mesh structure, allowing seawater to enter with low resistance while retaining precursors that can easily cause RO membrane fouling. As a replaceable primary filter element, cotton wadding layer 521 can be replaced with a polypropylene melt-blown filter layer, modified chitosan sponge, or nanocellulose aerogel layer, adapting to different water quality characteristics while ensuring adsorption capacity.

[0073] The RO reverse osmosis layer 522 is the core of the desalination function. It adopts an aromatic polyamide composite membrane with an asymmetric structure on its surface: the dense desalination surface faces inward into the tube, while the porous support surface faces outward and is attached to the support structure 523. This layer does not bear pressure alone; its mechanical stability depends entirely on the gap support and deformation buffer space provided by the pleated configuration formed by the external support structure 523, thereby preventing membrane collapse or peeling under periodic pressure difference changes.

[0074] Among them, the support structure 523 is located between the RO reverse osmosis layer 522 and the sintered PE layer 524. Its core function is to enable the RO reverse osmosis layer 522 to form a stable, uniform and repeatedly expandable / contractable axial fold structure. The structure is not limited to the sheet spring form defined in Specific Embodiment 8, but can also be a spirally wound elastic alloy wire mesh, circumferentially spaced annular elastic ribs, or a shape memory alloy corrugated skeleton formed by laser micromachining; to ensure that the RO layer expands its wrinkles to increase the effective filtration area when under pressure, and automatically rebounds and resets when pressure is released, preventing wrinkles from sticking together or permanent deformation.

[0075] Among them, the sintered PE layer 524 is a rigid reinforcement layer, which is made of high-density polyethylene (HDPE) powder through a molding and sintering process. The sintered PE layer 524 has both microfiltration function and mechanical load-bearing capacity. On the one hand, it can intercept submicron-sized particles that penetrate the cotton layer 521. On the other hand, it provides a flat and rigid attachment substrate for the outer woven protective layer 525 and evenly disperses the external bending stress to the entire circumference of the pipe wall, avoiding local stress concentration that could damage the inner RO membrane.

[0076] Among them, the braided protective layer 525 is the outermost physical barrier, which is made of high-strength polyester (PET) or ultra-high molecular weight polyethylene (UHMWPE) monofilaments woven in plain or twill weave. The surface is treated with silane coupling agent to improve the interfacial bonding strength with the sintered PE layer 524. It mainly resists the contact wear of the pipe support frame 41 in the freshwater storage tank 4, the scratching during manual maintenance, and the repeated flexural fatigue under S-shaped bending conditions. This layer can be replaced with a thermoplastic polyurethane (TPU) extrusion coating or a glass fiber reinforced epoxy resin coating to meet the requirements of higher mechanical strength or chemical corrosion resistance.

[0077] The layers are bonded together by gradient hot melt bonding or by applying a two-component polyurethane adhesive after plasma surface activation to achieve a void-free composite.

[0078] A detachable interface is provided between the cotton layer 521 and the RO reverse osmosis layer 522, such as a snap-on annular pressure ring or a magnetic positioning ring structure, which facilitates the periodic replacement of the cotton layer 521 without replacing the entire seawater permeation pipe 52, thus reducing operation and maintenance costs.

[0079] Through the above technical solution, this application achieves the following: when saline seawater enters the inner cavity of the seawater permeation pipe 52 at a controllable flow rate under the regulation of the water control valve 53, it first completes primary solid-liquid separation and ion adsorption through the cotton layer 521, which greatly reduces the fouling rate of the subsequent RO reverse osmosis layer 522; subsequently, under the pressure difference drive, water molecules selectively permeate through the RO reverse osmosis layer 522, while salt and large molecular solutes are intercepted and discharged along the pipe axis with the concentrate; the support structure 523 maintains the RO layer in a continuously pleated unfolded state, increasing the effective desalination area per unit length of the pipe body, thereby increasing the permeate flux under the same outer diameter constraint; the sintered PE layer 524 and the braided protective layer 525 jointly bear the external load, avoiding the reduction of the flow cross section or the instability of the RO layer pleats caused by local flattening under the S-shaped bending installation state. Therefore, this embodiment solves the technical problems of easy clogging, rapid flux decay, poor bending resistance and high maintenance cost of traditional single-layer RO pipes in nearshore seawater desalination, and achieves the technical effects of improving filtration accuracy, extending membrane life, enhancing structural robustness and reducing the cost of operation and maintenance throughout the entire cycle.

[0080] Reference Figure 2 , Figure 7 The cotton wadding locking component 526 includes a first threaded cylinder 5261 sleeved on the outside of the braided protective layer 525, an expansion sleeve 5262 detachably installed inside the first threaded cylinder 5261, a support threaded tube 5263 threadedly installed inside the expansion sleeve 5262, a limiting protrusion 5264 provided on the outside of the expansion sleeve 5262, a locking limiting groove 5265 that cooperates with the limiting protrusion 5264 provided on the inside of the first threaded cylinder 5261, and the first threaded cylinder 5261 connected to the seawater collection tank 51; an internal threaded sleeve is installed on the seawater collection tank 51, the first threaded cylinder 5261 is connected to the internal threaded sleeve, a sealing ring that abuts against the first threaded cylinder 5261 is provided on the inside of the internal threaded sleeve, and a torsion groove 5266 is provided at the end of the support threaded tube 5263; The expansion sleeve 5262 includes a central support section and expansion sections symmetrically arranged on both sides of the support section; the support threaded tube 5263 is arranged at both ends of the expansion sleeve 5262.

[0081] The support threaded tube 5263 supports both ends of the expansion sleeve 5262, so that both ends of the cotton wadding locking part 526 are locking structures. This prevents the cotton wadding layer 521 from being not securely locked due to one end of the cotton wadding locking part 526 being a locking structure and the other end being a loose structure, which would cause it to fall off during use.

[0082] This embodiment provides a mechanical locking structure for scenarios where the cotton layer 521 and the RO reverse osmosis layer 522 in the RO reverse osmosis seawater permeation pipe 52 can be detachably connected. Its core lies in generating radial tightening force through axial rotation, achieving reliable clamping, anti-detachment fixation, and interface sealing under high-pressure conditions for the multi-layer pipe assembly. This structure balances quick assembly / disassembly, reusability, and operational sealing, making it suitable for desalination scenarios with high requirements for ease of maintenance and environmental adaptability, such as islands, ships, or emergency water supply.

[0083] The first threaded cylinder 5261 is a hollow cylindrical metal cylinder, which can be made of stainless steel 304 or anodized aluminum alloy. The outer wall is provided with a standard metric external thread for screwing into the internal threaded sleeve on the seawater collection tank 51. The inner wall is machined with an annular locking and limiting groove 5265. The groove width and depth are adapted to the size of the limiting protrusion 5264 to ensure circumferential positioning accuracy. The first threaded cylinder 5261 is sleeved on the outside of the braided protective layer 525 and does not directly contact the internal functional layers. It only serves as an external load-bearing and guiding shell.

[0084] The expansion sleeve 5262 is an elastic thin-walled metal sleeve with a C-shaped or slit spiral cross-section. It is made of beryllium bronze or nickel-titanium shape memory alloy and has high elastic modulus and seawater corrosion resistance. Multiple limiting protrusions 5264 are evenly distributed around its outer wall in the circumferential direction. The protrusion cross-section is trapezoidal or arc-shaped. The expansion sleeve 5262 and the locking limiting groove 5265 on the inner wall of the first threaded cylinder 5261 form a sliding-anti-rotation fit. The expansion sleeve 5262 is inserted into the inner cavity of the first threaded cylinder 5261 in a clearance fit manner and can be freely installed and removed along the axial direction without relying on adhesive or welding. As an optional embodiment, the expansion sleeve 5262 can also be made of high-resilience silicone composite material with an internally embedded annular steel wire reinforcing skeleton to balance the elastic deformation and structural stiffness.

[0085] The support threaded tube 5263 is a solid or hollow cylindrical rod with a precision fine-tooth internal thread on its outer surface, which matches the thread on the inner wall of the expansion sleeve 5262. Its end is machined with a torsion groove 5266, which is a slotted groove, a cross groove, or a hexagonal recess, to facilitate the application of rotational torque by a general-purpose screwdriver, an Allen wrench, or a special torque tool. When the support threaded tube 5263 is screwed into the expansion sleeve 5262, its front conical or stepped surface pushes the expansion sleeve 5262 to expand radially outward, forcing the limiting protrusion 5264 to press into the locking limiting groove 5265. At the same time, the inner wall of the first threaded cylinder 5261 is compressed and contracts towards the center, thereby clamping the outer circle of the braided protective layer 525, achieving axial positioning and radial locking of the entire seawater permeation pipe 52. As an optional embodiment, the support threaded tube 5263 can also be replaced with a ratchet push rod with self-locking helical teeth, which achieves irreversible expansion and tightening through unidirectional rotation, suitable for long-term maintenance-free operation.

[0086] The internal threaded sleeve is fixed at the pipe flange or side wall interface of the seawater collection tank 51. Its internal thread specification is consistent with the external thread of the first threaded sleeve 5261, and its axis is coaxial with the installation direction of the seawater infiltration pipe 52. The sealing ring is an O-ring fluororubber ring (FKM) or perfluoroether rubber (FFKM) sealing ring, which is installed in the annular groove on the inner end face of the internal threaded sleeve. When the first threaded sleeve 5261 is screwed into place, its end face presses against the sealing ring to form a static sealing interface, preventing the high-pressure original seawater in the seawater collection tank 51 from leaking out along the interface gap. The synergistic relationship of the components is as follows: the rotational motion of the supporting threaded tube 5263 is converted into axial feed through the threaded pair, pushing the expansion sleeve 5262 to undergo controllable elastic deformation. Its limiting protrusion 5264 slides within the locking limiting groove 5265 and is finally locked, constraining the relative circumferential rotation. Simultaneously, the first threaded cylinder 5261, under the action of radial tightening force, tightly adheres to the outer surface of the braided protective layer 525, forming a mechanical engagement. The screwing action of the first threaded cylinder 5261 and the internal threaded sleeve completes the axial positioning and interface sealing of the overall structure. The sealing ring undergoes elastic filling under pre-tightening force, eliminating the microscopic gaps at the metal contact surface. The entire process requires no additional fasteners, adhesives, or thermal assembly processes, and all actions can be completed by a single person using hand tools at normal temperature and pressure.

[0087] Through the above technical solution, this application achieves the following: at the connection node between the seawater permeation pipe 52 and the seawater collection tank 51, a quick-release interface structure integrating mechanical locking, anti-detachment fixation, and dynamic sealing is constructed. Because the supporting threaded pipe 5263 receives external torque input through the torsion groove 5266, the expansion sleeve 5262 generates radial expansion force, thus firmly clamping the multi-layer composite pipe body and preventing the cotton layer 521 and the RO reverse osmosis layer 522 from axial movement or interlayer peeling under water flow impact or vibration; because the limiting protrusion 5264 and the locking limiting groove 5265 cooperate to limit relative rotation, the first threaded cylinder 5261 is prevented from loosening due to vibration during long-term operation; because a sealing ring is set between the first threaded cylinder 5261 and the inner threaded sleeve to form a surface pressure seal, the leakage of high-pressure raw seawater from the interface is effectively blocked, ensuring the system stability and freshwater production purity of the seawater treatment component 5 under the condition of pressure differential adjustment by the water control valve 53.

[0088] Reference Figure 8 , Figure 9The piston block 32 includes a piston cylinder 321. Multiple positioning grooves 322 are formed on the piston cylinder 321. A sealing ring 323 is fitted onto each positioning groove 322. A locking strip 324 is provided inside the sealing ring 323. A side hole 325 is formed on the piston cylinder 321. The locking strip 324 passes through the side hole 325 and is connected together by a sealing locking member 326. The sealing locking member 326 includes an upper clamping plate 3261 and a lower clamping plate 3262. The upper clamping plate 3261 and the lower clamping plate 3262 are connected together by bolts. A limiting ring 3263 is installed on the upper clamping plate 3261. A rubber strip limiting groove 3264 is formed on the limiting ring 3263 for the locking strip 324 to pass through. The lower clamping plate 3262 is installed inside the limiting ring 3263.

[0089] This embodiment provides an adjustable modular piston sealing structure. Its core lies in a three-level collaborative constraint mechanism—positioning groove, locking strip, and clamping plate—that achieves dynamic fit, uniform force distribution, and convenient replacement of the sealing ring during piston movement. This structure does not rely on integral interference fit or non-removable bonding; instead, it establishes sealing preload in a mechanically reversible manner, balancing high sealing performance, long service life, and on-site maintainability.

[0090] The piston cylinder 321 is a hollow cylindrical load-bearing body made of seawater-resistant 316L stainless steel or reinforced polypropylene PP-R. Its outer diameter matches the inner cavity of the water intake cylinder 31 to ensure smooth axial sliding without radial wobbling. The cylinder wall is evenly distributed with annular positioning grooves 322 along the axial direction. Each set of positioning grooves is a rectangular cross-section groove, which is used to accurately embed and limit the base part of the sealing ring 323 to prevent it from axial movement or torsional displacement during reciprocating motion.

[0091] The sealing ring 323 is an elastic component made of fluororubber (FKM) or hydrogenated nitrile rubber (HNBR), with a D-shaped or O-shaped cross section. Its outer edge forms a surface contact seal with the inner wall of the water intake cylinder 31. A locking strip 324 is integrally formed or embedded on its inner side. The locking strip 324 is continuously arranged along the inner circumference of the sealing ring 323, with lap allowance reserved at both ends. Its function is to convert the external clamping force into a uniform radial pressing force on the sealing ring.

[0092] The side hole 325 is a through hole that penetrates the wall of the piston cylinder 321. It is located in the middle section of the cylinder wall at the axial position of the positioning groove 322, and the hole axis is perpendicular to the cylinder axis. Its function is to provide a path for the locking strip 324 to extend from the inside of the sealing ring 323 into the inside of the piston cylinder 321, thereby entering the working area of ​​the sealing locking element 326.

[0093] The sealing and locking component 326 consists of an upper clamping plate 3261, a lower clamping plate 3262, and connecting bolts. The upper clamping plate 3261 and the lower clamping plate 3262 are stacked to form a clamping cavity, the size of which matches the cross-section of the locking strip 324. The two are connected by two sets of internal hexagonal head bolts 3265 to ensure stable clamping force and prevent plastic deformation of the locking strip. This structure is different from the traditional integral pressure cap and realizes the regional and quantifiable application of clamping force.

[0094] The limiting ring 3263 is an annular boss structure, integrally cast or welded to the upper clamping plate 3261. Its inner diameter is slightly larger than the outer diameter of the piston cylinder 321. The rubber strip limiting groove 3264 opened on it is a U-shaped through groove that runs axially through the ring. It is used to guide and constrain the direction of the locking strip 324 to prevent it from buckling laterally or stacking locally during clamping. In another embodiment, the rubber strip limiting groove 3264 can be replaced with a double-row parallel guide groove, which, together with the flange structure on both sides of the locking strip 324, further improves the guiding stability.

[0095] The lower clamping plate 3262 is installed inside the limiting ring 3263, that is, its end face facing the piston cylinder 321 is flush with or slightly recessed with the inner end face of the limiting ring 3263, ensuring that the lower clamping plate 3262 first contacts the locking strip 324 and forms initial support when clamped, avoiding the upper clamping plate 3261 being subjected to unilateral cantilever force; this installation relationship is naturally achieved through the geometric constraints of the limiting ring 3263, without the need for additional positioning pins or screws, simplifying the assembly process.

[0096] The collaborative relationship between the components is as follows: the positioning groove 322 first performs axial and circumferential initial positioning of the sealing ring 323; the locking strip 324 anchors the inner edge of the sealing ring 323; the sealing locking element 326 applies a compressive force perpendicular to the cylinder wall to the locking strip 324 through the upper clamping plate 3261 and the lower clamping plate 3262. This force is transmitted to the inner side of the sealing ring 323 through the locking strip 324, forcing the outer edge of the sealing ring 323 to expand elastically and fit tightly against the inner wall of the water intake cylinder 31; the limiting ring 3263 and its rubber strip limiting groove 3264 constrain the straightness and positional stability of the locking strip 324 throughout the process, ensuring that the clamping force is evenly distributed.

[0097] Reference Figure 3 , Figure 8 , Figure 9Through the above technical solution, this application achieves the following: when the float 36 swings with the wave of the sea surface, the torque rod 34 swings, and the traction rod 33 drives the piston block 32 to make reciprocating linear motion in the water intake cylinder 31; during this process, the sealing locking element 326 continuously provides controllable clamping force, so that the locking strip 324 always applies a stable radial compression component to the sealing ring 323, overcoming the rebound attenuation of the sealing ring caused by seawater sand, temperature changes and long-term wear; once the sealing performance deteriorates, only the bolts need to be loosened to remove the sealing locking element 326 and the locking strip 324 as a whole, and then the old sealing ring 323 can be pulled out from the positioning groove 322 and replaced with a new one, without disassembling the water intake cylinder 31 or the piston cylinder 321 body throughout the process. By setting a positioning groove 322 to axially limit the sealing ring 323, the problem of axial displacement and local leakage caused by traditional piston sealing rings is solved. By introducing a locking strip 324 and an adjustable sealing locking element 326, the problem of uncontrollable sealing preload and inability to adapt to different wear stages is solved. By configuring a limiting ring 3263 and a rubber strip limiting groove 3264 to guide and constrain the locking strip 324, the problem of bending and instability of the locking strip during clamping and uneven force on the sealing ring is solved. Ultimately, the technical effects of high sealing reliability, fast maintenance response and long service life are achieved.

[0098] The embodiments described in this specific implementation are preferred embodiments of this application and are not intended to limit the scope of protection of this application. Identical components are represented by the same reference numerals. Therefore, all equivalent changes made to the structure, shape, and principle of this application should be covered within the scope of protection of this application.

Claims

1. A seawater desalination treatment device, characterized in that, The system includes a base (1), a seawater storage tank (2) for storing seawater is provided below the base (1), a seawater conveying device (3) is fixed on the base (1), a freshwater storage tank (4) is provided on one side of the seawater storage tank (2), and a seawater treatment component (5) is provided between the seawater storage tank (2) and the freshwater storage tank (4). The seawater treatment component (5) includes a seawater collection tank (51), a plurality of seawater permeation pipes (52) are installed on the seawater collection tank (51), the seawater permeation pipes (52) are placed in the freshwater storage tank (4) in an S-shape, the seawater permeation pipes (52) are used to extract freshwater from seawater, and a water control valve (53) is provided at the end of the seawater permeation pipe (52) away from the seawater conveying device (3). The water control valve (53) is used to control the water flow, so that a pressure difference is generated in the seawater permeation pipe (52) and the high-concentration brine after the freshwater is extracted is discharged. A freshwater conveying pipe (7) is installed on the freshwater storage tank (4).

2. The seawater desalination treatment device according to claim 1, characterized in that, The seawater conveying device (3) includes multiple water intake cylinders (31) fixed on a base (1). A piston block (32) is installed inside the water intake cylinder (31). A traction rod (33) is installed on the piston block (32). A torque rod (34) is hinged to the traction rod (33). A water conveying support frame (35) is fixed on the base (1). The water conveying support frame (35) is hinged to the torque rod (34). A float (36) is hinged to the end of the torque rod (34) away from the water intake cylinder (31). A counterweight (37) is fixed on the float (36), and the float (36) floats on the sea surface; an inlet check valve (38) is fixed at the lower end of the water intake tube (31), and an outlet check valve (39) is fixed on the side of the water intake tube (31). An inlet pipe (310) is installed on the inlet check valve (38), and the inlet pipe (310) is inserted into the seawater storage tank (2). An outlet pipe (311) is installed on the outlet check valve (39), and the outlet pipe (311) is connected to the seawater collection tank (51).

3. The seawater desalination device according to claim 2, characterized in that, The water intake cylinder (31) is symmetrically arranged on both sides of the water conveyance support frame (35), and the torque rod (34) controls a pair of traction rods (33) to move up and down.

4. The seawater desalination treatment device according to claim 1, characterized in that, A booster pump (6) is installed on the base (1). The booster pump (6) is equipped with a water pumping pipe (61) and a water delivery pipe (62). The water pumping pipe (61) is connected to the seawater collection tank (51), and the water delivery pipe (62) is connected to the seawater collection tank (51).

5. A seawater desalination treatment device according to claim 1, characterized in that, The seawater storage tank (2) is buried in the sand. A seawater filtration zone (21) is set on the side of the seawater storage tank (2) that is close to the sea. The seawater filtration zone (21) is arranged from the outside to the inside as a coarse filtration zone (22), an adsorption zone (23) and an ultrafiltration zone (24). The coarse filtration zone (22) is used to filter plankton in the seawater. The adsorption zone (23) is filled with activated carbon to adsorb organic matter in the seawater. The ultrafiltration zone (24) is equipped with an ultrafiltration membrane to filter fine impurities in the seawater.

6. The seawater desalination treatment device according to claim 1, characterized in that, A pipe support frame (41) is provided in the freshwater storage tank (4). The pipe support frame (41) is used to support the seawater infiltration pipe (52) so that the seawater infiltration pipe (52) is placed in the freshwater storage tank (4) in an S-shape.

7. A seawater desalination treatment device according to claim 1, characterized in that, The seawater permeation pipe (52) includes a cotton wadding layer (521), an RO reverse osmosis layer (522) is provided on the outside of the cotton wadding layer (521), a support structure (523) is provided on the outside of the RO reverse osmosis layer (522), the support structure (523) is used to make the RO reverse osmosis layer (522) into a pleated structure, a sintered PE layer (524) is provided on the outside of the support structure (523), and a braided protective layer (525) is provided on the outside of the sintered PE layer (524); the cotton wadding layer (521) is used to adsorb impurities and salt in seawater and protect the RO reverse osmosis layer (522).

8. A seawater desalination treatment device according to claim 7, characterized in that, The support structure (523) is a spring, and the spring is a sheet structure; the cotton layer (521) and the RO reverse osmosis layer (522) are detachably connected, and a cotton locking component (526) is installed in the seawater permeation pipe (52).

9. A seawater desalination treatment device according to claim 8, characterized in that, The cotton wadding locking component (526) includes a first threaded cylinder (5261) sleeved on the outside of the braided protective layer (525), an expansion sleeve (5262) ​​detachably installed inside the first threaded cylinder (5261), a support threaded tube (5263) threadedly installed inside the expansion sleeve (5262), a limiting protrusion (5264) provided on the outside of the expansion sleeve (5262), a locking limiting groove (5265) cooperating with the limiting protrusion (5264) provided on the inside of the first threaded cylinder (5261), and the first threaded cylinder (5261) connected to the seawater collection tank (51); an internal threaded sleeve is installed on the seawater collection tank (51), the first threaded cylinder (5261) is connected to the internal threaded sleeve, a sealing ring abutting against the first threaded cylinder (5261) is provided inside the internal threaded sleeve, and a torsion groove (5266) is provided at the end of the support threaded tube (5263). The expansion sleeve (5262) ​​includes a middle support section and expansion sections symmetrically arranged on both sides of the support section; the support threaded pipe (5263) is arranged at both ends of the expansion sleeve (5262).

10. A seawater desalination treatment device according to claim 3, characterized in that, The piston block (32) includes a piston cylinder (321), on which a plurality of positioning grooves (322) are provided. A sealing ring (323) is fitted on the positioning groove (322). A locking strip (324) is provided inside the sealing ring (323). A side hole (325) is provided on the piston cylinder (321). The locking strip (324) passes through the side hole (325). The locking strip (324) is connected together by a sealing locking member (326). The locking fastener (326) includes an upper clamping plate (3261) and a lower clamping plate (3262), which are connected together by bolts; a limiting ring (3263) is installed on the upper clamping plate (3261), and a rubber strip limiting groove (3264) is provided on the limiting ring (3263), which is used for the locking strip (324) to pass through; the lower clamping plate (3262) is installed inside the limiting ring (3263).

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