Secondary high-pressure pump, reverse osmosis mechanism and system for preparing edible salt from seawater

Abstract

According to the two-stage high-pressure pump, the reverse osmosis mechanism and the system for preparing the edible salt from the seawater, the two-stage high-pressure pump is provided with the plunger, namely the displacement pump, has the advantages of being large and stable in flow, high in energy utilization efficiency, compact in structure and the like, and is driven by the servo motor; compared with a traditional asynchronous motor and the like, the servo motor is small in size and capable of achieving high-precision control, the size of the pump is smaller, and response can be made more rapidly and accurately when the working condition of the system changes. Moreover, the middle part of the plunger is provided with a stress surface, and the fluid end is provided with a high-pressure backflow channel communicated with the high-pressure water outlet flow channel and the rear cavity body of the plunger movable cavity, so that the output water pressure can act on the stress surface, and the input water pressure borne by the front end of the plunger is balanced; the axial force required by the plunger of the second-stage high-pressure pump is greatly reduced, so that further pressurization of concentrated seawater can be realized with obviously lower energy consumption, and the second-stage high-pressure pump can be used for realizing a low-energy-consumption multi-stage reverse osmosis module.

Description

TECHNICAL FIELD

[0001] The utility model belongs to high pressure liquid pump technical field, concretely relates to a two-stage high pressure pump, reverse osmosis mechanism and seawater edible salt system. BACKGROUND

[0002] Traditionally, the way of making salt from seawater includes boiling salt method, sunning method, spray evaporation method and the like, these methods have respective defects, among them, the boiling salt method not only consumes a great deal of electricity, but also can only make industrial salt usually; The sunning method needs a large area and a large amount of manpower to carry out salt drying, and the production cycle is long and the output is unstable; The spray evaporation method also needs a large area and high energy consumption. Therefore, these traditional methods cannot make edible salt efficiently and energy-savingly.

[0003] There is a kind of membrane method for making fresh water system in the prior art, and the corresponding making method mainly includes collecting raw water, filtering and reverse osmosis treatment to seawater, after passing through the reverse osmosis membrane, the seawater is separated into fresh water and concentrated waste water, since the system is added with cleaning agent to avoid equipment blockage, therefore the concentrated waste water cannot be used for making edible salt. The inventor improves the above-mentioned membrane method for making fresh water system to form an efficient and energy-saving seawater edible salt system. In the new system, a plurality of reverse osmosis modules are adopted, and the concentrated salt water with higher salt content is output step by step, so that the time of subsequent salt drying and the like can be reduced, and the efficiency of making edible salt can be improved. The reverse osmosis module usually includes a high pressure pump and a reverse osmosis membrane, in the above-mentioned new system, some existing high pressure liquid pumps cannot be applied to the second and subsequent reverse osmosis modules, therefore a new two-stage high pressure pump is needed, mainly for the following reasons:

[0004] Using the existing high pressure pump, only a multi-stage reverse osmosis module with a traditional structure can be formed, in the traditional structure, a temporary storage tank is arranged between the two adjacent reverse osmosis modules, the concentrated salt water treated by the first stage reverse osmosis is first stored in the tank, and then is extracted by the high pressure pump of the second stage reverse osmosis module and passes through the second stage reverse osmosis membrane. That is, the high pressure pump of each stage needs to pressurize the seawater / concentrated salt water from the normal pressure to the high pressure, therefore the energy consumption is very high, which leads to that the scheme does not have practical application value.

[0005] In addition, the secondary high-pressure pump used in the new system also faces other challenges. On the one hand, the new system needs to run for a long time or even all day long, and the secondary high-pressure pump circulates the concentrated brine for a long time, so that the components of the secondary high-pressure pump are corroded by the concentrated brine, and under the action of high pressure, the salt and other components in the concentrated brine are precipitated in the form of microcrystals, which causes wear to the components of the secondary high-pressure pump, resulting in high maintenance costs. On the other hand, the inventor hopes to integrate the new system in a limited space, for example, in the space of a container, so the secondary high-pressure pump needs to be relatively small in size, and the noise and vibration generated by the secondary high-pressure pump need to be reduced. However, the existing high-pressure pumps of this type use asynchronous or variable frequency motors, which occupy a large space, and the high motor speed leads to high noise and vibration, and small pumps are difficult to meet the flow demand. Utility model content

[0006] The utility model discloses to solve at least one of above-mentioned problems, and the purpose is to provide a kind of secondary high-pressure pump with large flow, lower energy consumption and more miniaturization, reverse osmosis mechanism using the secondary high-pressure pump and the seawater edible salt system comprising the reverse osmosis mechanism, the utility model has adopted following technical scheme:

[0007] The utility model provides a kind of secondary high-pressure pump, it is arranged in the at least second level reverse osmosis module of seawater edible salt system, for further pressurization to the concentrated seawater that passes through the reverse osmosis module of previous level, it has such technical features, the secondary high-pressure pump includes: hydraulic end, for the pressurization of the concentrated seawater;Power end, for the power end of the hydraulic end is provided with power;Reduction gearbox is connected with the power end;And servo motor is connected with the reduction gearbox, wherein the hydraulic end includes: hydraulic end valve box, with the high-pressure water outlet flow channel for outputting the concentrated seawater after further pressurization, plunger movable cavity and high-pressure backflow passage;And plunger, reciprocatingly set in the plunger movable cavity, with the rear force surface of middle part towards the power end, wherein the high-pressure backflow passage is communicated with the high-pressure water outlet flow channel, the plunger movable cavity respectively, so that the pressure of the concentrated seawater after further pressurization acts on the rear force surface.

[0008] The utility model provides a kind of secondary high-pressure pump, it is arranged in the at least second level reverse osmosis module of seawater edible salt system, for further pressurization to the concentrated seawater that passes through the reverse osmosis module of previous level, it has such technical features, the secondary high-pressure pump includes: hydraulic end, for the pressurization of the concentrated seawater;Power end, for the power end of the hydraulic end is provided with power;Reduction gearbox is connected with the power end;And servo motor is connected with the reduction gearbox, wherein the hydraulic end includes: hydraulic end valve box, with the high-pressure water outlet flow channel for outputting the concentrated seawater after further pressurization, plunger movable cavity and high-pressure backflow passage;And plunger, reciprocatingly set in the plunger movable cavity, with the rear force surface of middle part towards the power end, wherein the high-pressure backflow passage is communicated with the high-pressure water outlet flow channel, the plunger movable cavity respectively, so that the pressure of the concentrated seawater after further pressurization acts on the rear force surface. 2 ~1200mm 2 , preferably 850mm 2 ~900mm 2The wall thickness of the liquid end valve box is 3-12 mm, preferably 5-10 mm; and the rotation speed of the servo motor is 1000 r / min, and the reduction ratio of the reduction box is 2.5-3.5.

[0009] The two-stage high-pressure pump further has the following technical features: the power end has a power output component moving along the reciprocating direction; the liquid end further comprises a floating connection assembly, which comprises: a connection component, one end of which is fixed to the power output component, and the other end of which has a receiving groove, the middle part of the bottom surface of the receiving groove being a spherical surface, used for abutting against one end of the plunger when the power output component moves towards the plunger, so that the thrust output by the power output component is kept acting on the central shaft of the plunger; a positioning component, which is sleeved on the end of the plunger having the flange and the connection component; and a sealing limiting component, which is fixed at the slot opening of the receiving groove, used for limiting the end of the plunger having the flange, and used for sealing between the connection component and the plunger.

[0010] The two-stage high-pressure pump further has the following technical features: the plunger comprises a plunger cylinder made of ceramic material; the liquid end valve box has independent seawater and fresh water channels; the seawater channel comprises the high-pressure water outlet flow channel, the high-pressure return flow channel and the plunger movable cavity; the liquid end further comprises: a flow guide component, which is sleeved on the plunger and is closer to the power end relative to the stress surface, has a flow guide channel communicating with the fresh water channel, and is used for guiding fresh water from the fresh water channel to the outer circumferential surface of the plunger, so as to lubricate and cool the plunger; and flow guide sealing assemblies, which are respectively arranged on the two sides of the flow guide component, and respectively seal between the two sides of the flow guide component and the plunger.

[0011] The two-stage high-pressure pump further has the following technical features: the power end comprises a power end valve box; the reduction box is arranged on one side of the power end valve box; the servo motor is horizontally arranged on one side of the reduction box, and its output end is connected to the input end of the reduction box through a shaft coupling; the liquid end valve box further has a plurality of detection component mounting holes communicating with the high-pressure water outlet flow channel, respectively used for mounting an accumulator, an electronic pressure gauge and a mechanical pressure gauge; the accumulator is used for stabilizing water outlet pressure, and has an inner cavity communicating with the high-pressure water outlet flow channel, which is filled with gas.

[0012] The two-stage high-pressure pump provided by the utility model also can have such technical features, wherein, the plunger comprises a plunger cylinder, the plunger cylinder is made of ceramic material, the liquid end valve box has independent seawater channel and fresh water channel, the seawater channel comprises the high-pressure water outlet flow channel, the high-pressure return flow channel and the plunger movable cavity, the liquid end further comprises: flow guide component, the flow guide component is sleeved on the plunger, and the flow guide component is closer to the power end relative to the stress surface, the flow guide component has flow guide channel that communicates with the fresh water channel, and the flow guide channel is used for guiding fresh water from the fresh water channel to the outer circumferential surface of the plunger, thereby lubricating and cooling the plunger, and flow guide sealing assembly is arranged on both sides of the flow guide component respectively, and both sides of the flow guide component and the plunger are sealed respectively.

[0013] The two-stage high-pressure pump provided by the utility model also can have such technical features, wherein, the liquid end further has high-pressure water inlet flow channel that communicates with the plunger movable cavity, the liquid end further comprises a plurality of one-way valves, the one-way valves comprise water inlet valve and water outlet valve, and the water inlet valve and the water outlet valve are arranged in the high-pressure water inlet flow channel and the high-pressure water outlet flow channel respectively, the one-way valve comprises valve body, titanium alloy valve core arranged in the valve body and reset component used for resetting the valve core, the valve core has: valve core main body, movably arranged in the valve body inner cavity, and rear guide part, formed at one end of the valve core main body located upstream of the concentrated seawater flow direction, used for guiding the concentrated seawater, so that the pressure generated by the concentrated seawater acts uniformly on the surface of the valve core main body.

[0014] The two-stage high-pressure pump provided by the utility model also can have such technical features, wherein, the liquid end valve box comprises box main part, a plurality of cover pieces and a plurality of cover sealing pieces, the plunger is a plurality of, the water inlet valve and the water outlet valve are a plurality of groups, and the water inlet valve and the water outlet valve are arranged respectively corresponding to each plunger, the box main part has: water inlet valve maintenance opening, communicating with the high-pressure water inlet flow channel, and the diameter of the water inlet valve maintenance opening corresponds to the diameter of the water inlet valve, and water outlet valve maintenance opening, communicating with the high-pressure water outlet flow channel, and the diameter of the water outlet valve maintenance opening corresponds to the diameter of the water outlet valve, a plurality of cover pieces and a plurality of cover sealing pieces are detachably installed at the water inlet valve maintenance opening and the water outlet valve maintenance opening.

[0015] The utility model provides a kind of reverse osmosis mechanism, it has such technical features, the reverse osmosis mechanism comprises: multistage reverse osmosis module, wherein, at least second stage the reverse osmosis module comprises: two-stage high-pressure pump, for the concentrated seawater of the reverse osmosis module of previous stage pressurization further pressurization;And reverse osmosis part, for the concentrated seawater after further pressurization is handled by reverse osmosis, to separate out further concentrated concentrated seawater from the concentrated seawater. Wherein, two-stage high-pressure pump is the two-stage high-pressure pump described above.

[0016] The utility model provides a kind of seawater edible salt system, it has such technical features, the system includes: reverse osmosis mechanism, for the reverse osmosis treatment to seawater, to separate out concentrated brine from the seawater. Among them, reverse osmosis mechanism is the reverse osmosis mechanism described above.

[0017] Practical new effect and advantage

[0018] According to the two-stage high-pressure pump, the reverse osmosis mechanism and the seawater edible salt system provided by the utility model, the liquid end of the two-stage high-pressure pump has a plunger, and the plunger is driven to move by a servo motor and a speed reducer, i.e., the pump is a positive displacement pump, which has the advantages of large and stable flow, high energy utilization efficiency, compact structure, etc., and the servo motor is smaller in size than a conventional asynchronous motor and can achieve high-precision control. Therefore, the two-stage high-pressure pump is significantly smaller in size while maintaining ideal flow, and can achieve rapid and accurate response when the system operating conditions change, so that the concentrated seawater output by the reverse osmosis module is stable in quality, which is conducive to the stable and efficient production of edible salt.

[0019] Further, the plunger has a stress surface facing the power end, and the liquid end has a high-pressure return channel in communication with the high-pressure water outlet flow channel and the rear cavity of the plunger movable cavity, respectively. Therefore, the pressure of the concentrated seawater further pressurized by the two-stage high-pressure pump (i.e., the output water pressure) can act on the stress surface, partially offsetting or completely balancing the input water pressure received by the front end of the plunger. In this way, for the same output water pressure, the axial force required by the plunger of the two-stage high-pressure pump is greatly reduced, so that the concentrated seawater can be further pressurized with significantly lower energy consumption, and a multi-stage reverse osmosis module with low energy consumption can be realized using the two-stage high-pressure pump. In the seawater edible salt system, multi-stage reverse osmosis is realized, high-concentration concentrated seawater is output, the time required for subsequent salt drying and other processes is shortened, and the yield and output efficiency of edible salt are improved. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 is a perspective view of the two-stage high-pressure pump in the embodiment of the utility model;

[0021] Figure 2 is a sectional view of the two-stage high-pressure pump in the embodiment of the utility model;

[0022] Figure 3 is Figure 2 is an enlarged view of the inner part of the middle frame A;

[0023] Figure 4 is a sectional view of the liquid end valve box in the embodiment of the utility model;

[0024] Figure 5 is a perspective view of the one-way valve in the embodiment of the utility model;

[0025] Figure 6 is a structure exploded view of the one-way valve in the embodiment of the utility model;

[0026] Figure 7 is Figure 2 the enlarged view of the inner part of the middle frame B;

[0027] Figure 8 is the perspective view of the flow guide component in the embodiment of the utility model;

[0028] Figure 9 is the perspective view of the two-stage high-pressure pump in the embodiment of the utility model Figure 1 .

[0029] Figure 10 is the perspective view of the two-stage high-pressure pump in the embodiment of the utility model Figure 2 .

[0030] Reference signs:

[0031] two-stage high-pressure pump 72; fixed base 721; support leg 7211; hydraulic end 722; hydraulic end valve box 7221; first main body component 7221A; second main body component 7221B; box connecting component 7221C; cover 7221D; cover sealing assembly 7221E; high-pressure water inlet flow channel 72211; high-pressure water inlet 72211a; high-pressure water outlet flow channel 72212; high-pressure water outlet 72212a; pressurized flow channel 72213; water outlet valve maintenance opening 72213a; water inlet valve maintenance opening 72213b; plunger movable cavity 72214; front cavity 72214a; rear cavity 72214b;

[0032] fresh water inlet flow channel 72215; fresh water inlet 72215a; drainage air flow channel 72216; drainage air outlet 72216a; high-pressure backflow channel 72217; air flow channel 72218; plunger 7122; plunger barrel 71221; plunger fixing part 71222; plunger base part 71223; flange 71223a; rear end stress surface 7222A; front end stress surface

[0033] 7222B; one-way valve 7223; water inlet valve 7223A; water outlet valve 7223B; valve cover 72231; matching protrusion 72231a; water outlet hole 72231b; water passing hole 72231c; valve seat 72232; water inlet hole 72232a; valve core

[0034] 72233; valve core body 72233A; flow guide part 72233B; plate-shaped part 72234; floating connection assembly 7224; connection part 72241; accommodating groove 72241b; mounting groove 72241c; positioning part 72242; air hole 72242a; spherical part 72243; first driving part 72244; second driving part 72245; front end high pressure sealing assembly 72251; front end low pressure sealing assembly 72252; rear end high pressure sealing assembly 72253; rear end low pressure sealing assembly 72254; flow guide part 7226; outer circumferential ring groove 72261; inner circumferential ring groove 72262; flow guide hole 72263; power end 723; power end valve box 7231; crankshaft 7232; connecting rod 7233; pump driving mechanism 724; servo motor 7241; speed reducer 7242; coupling 7243; coupling housing 7244; accumulator 7251; electronic pressure gauge 7252; mechanical pressure gauge 7253. DETAILED DESCRIPTION

[0035] In order to make the technical means, creative features, purposes and effects of the utility model easy to understand, the following will make a specific description of the two-stage high-pressure pump, reverse osmosis mechanism and seawater edible salt system of the utility model in combination with embodiments and drawings.

[0036] <EMBODIMENT>

[0037] The embodiment provides a two-stage high-pressure pump arranged in a seawater edible salt system. The system is arranged in a container and comprises a clean seawater obtaining device and a concentrated brine obtaining device.

[0038] The clean seawater obtaining device is used for performing pre-treatment such as filtration on input raw seawater, so that the raw seawater becomes clean seawater with basically unchanged salt content but lower turbidity, and the clean seawater is supplied to the concentrated brine obtaining device.

[0039] The concentrated brine obtaining device comprises a reverse osmosis mechanism and a concentrated brine output mechanism. The reverse osmosis mechanism comprises at least two stages of reverse osmosis modules, each stage of reverse osmosis module comprises a high-pressure pump and a reverse osmosis part (reverse osmosis membrane), and the high-pressure pump is used for pressurizing seawater to be input into the reverse osmosis membrane, so that the membrane structure of the reverse osmosis membrane and the pressure difference between the two sides thereof are used to separate water molecules from salt and other impurities, and separated fresh water and concentrated seawater (also referred to as concentrated brine) are obtained. The high-pressure pump in the first stage of reverse osmosis module can adopt the structure in the prior art, and the high-pressure pump in the second stage of reverse osmosis module is the two-stage high-pressure pump provided in the embodiment. When there are more stages of reverse osmosis modules, the high-pressure pumps in the third stage and above of reverse osmosis modules can select the two-stage high-pressure pump of the embodiment.

[0040] The structure of the two-stage high-pressure pump will be described in detail below.

[0041] Figure 1 is a perspective view of the secondary high-pressure pump in the embodiment, Figure 2 is a sectional view of the secondary high-pressure pump in the embodiment.

[0042] As shown in Figure 1 and Figure 2 , the secondary high-pressure pump 72 comprises a fixed base 721, a hydraulic end 722, a power end 723, and a pump driving mechanism 724.

[0043] The fixed base 721 is a square frame structure, and the hydraulic end 722, the power end 723, the reduction box 724, and the servo motor 725 are all fixed on the fixed base 721. The bottom of the fixed base 721 has a plurality of support feet 7211, which can be made of elastic material and have a certain damping effect.

[0044] Figure 3 is Figure 2 an enlarged view of the inner part of the middle frame A.

[0045] As shown in Figure 2 and Figure 3 , the hydraulic end 722 is used to input seawater, increase the pressure of the seawater, and output the pressurized seawater to a reverse osmosis part (for example, a reverse osmosis membrane). The hydraulic end 722 comprises a hydraulic end valve box 7221, a plurality of plungers 7222, a plurality of one-way valves 7223, a plurality of floating connection assemblies 7224, a plurality of plunger sealing assemblies 7225, and a plurality of flow guide components 7226.

[0046] The hydraulic end valve box 7221 comprises a first body component 7221A, a second body component 7221B, a box connecting component 7221C, a plurality of cover pieces 7221D, and a plurality of cover sealing assemblies 7221E.

[0047] The first body component 7221A and the second body component 7221B are both roughly cuboid in shape, and the box connecting component 7221C is roughly trapezoidal in shape. The length of the second body component 7221B is the same as that of the first body component 7221A, and the width and height of the second body component 7221B are smaller than those of the first body component 7221A. The width and height of the box connecting component 7221C are smaller than those of the second body component 7221B. The box connecting component 7221C, the second body component 7221B, and the first body component 7221A are sequentially installed at the front end of the power end 723, and are fixed by a plurality of long screws. The plurality of cover pieces 7221D and the plurality of cover sealing assemblies 7221E are respectively arranged at a plurality of openings on the first body component 7221A, and are used to seal and shield the openings.

[0048] Figure 4 is a sectional view of the hydraulic end valve box in the embodiment.

[0049] AsFigures 2 to 4 As shown, the hydraulic end valve box 7221 is internally formed with a seawater passage, a fresh water passage, a plunger cavity and a high-pressure return passage. The seawater passage and the fresh water passage are independent of each other.

[0050] The seawater passage includes a high-pressure water inlet flow channel 72211, a high-pressure water outlet flow channel 72212 and a plurality of pressurizing flow channels 72213.

[0051] The high-pressure water inlet flow channel 72211 extends along the length direction of the hydraulic end valve box 7221 and penetrates through the hydraulic end valve box 7221, and is located at the lower part of the hydraulic end valve box 7221. The cross section of the high-pressure water inlet flow channel 72211 is circular, and both ends of the high-pressure water inlet flow channel 72211 are two high-pressure water inlet openings 72211a located at the lower part of both sides of the hydraulic end valve box 7221.

[0052] The high-pressure water outlet flow channel 72212 extends along the length direction of the first main body part 7221A and penetrates through the first main body part 7221A, and is located at the upper part of the hydraulic end valve box 7221. The cross section of the high-pressure water outlet flow channel 72212 is circular, and both ends of the high-pressure water outlet flow channel 72212 are two high-pressure water outlet openings 72212a located at the upper part of both sides of the hydraulic end valve box 7221. The diameter of the high-pressure water outlet opening 72212a is smaller than the diameter of the high-pressure water inlet opening 72211a. The high-pressure water outlet opening 72212a can be connected to the water inlet opening of the reverse osmosis membrane of the present stage through a corresponding pipeline.

[0053] The plurality of pressurizing flow channels 72213 are respectively used for cooperating with corresponding plungers and one-way valves to realize pressurization of seawater. Each pressurizing flow channel 72213 is substantially in the shape of a “N” character. The upper end of each pressurizing flow channel 72213 is in communication with the high-pressure water outlet flow channel 72212, one end of the lower part of each pressurizing flow channel 72213 is in communication with the high-pressure water inlet flow channel 72211, and the upper end of each pressurizing flow channel 72213 is in communication with the outside. A circular water outlet valve maintenance opening 72213a is formed on the upper surface of the hydraulic end valve box 7221, and the other end of the lower part of each pressurizing flow channel 72213 is also in communication with the outside. A circular water inlet valve maintenance opening 72213b is formed on the front end surface of the hydraulic end valve box 7221.

[0054] The plunger cavity 72214 is used for arranging a plunger and extends along the width direction of the hydraulic end valve box 7221. The first main body part 7221A and the second main body part 7221B each have a part of the plunger cavity 72214. The cross section of the plunger cavity 72214 is circular, one end of the plunger cavity 72214 is in communication with the middle part of the corresponding pressurizing flow channel 72213, and the other end of the plunger cavity 72214 is in communication with the outside. The other end of the plunger cavity 72214 has a multi-stage stepped structure.

[0055] The fresh water passage is used for cooperating with a flow guide part to realize fresh water lubrication and cooling of the plunger, and includes a plurality of fresh water inlet flow channels 72215 and a plurality of drainage air flow channels 72216.

[0056] The fresh water inlet passage 72215 extends along the length direction of the first main body part 7221A, from the hydraulic end valve box 7221 side to the vicinity of the plunger movable cavity 72214, and has a fresh water inlet port 72215a at the hydraulic end valve box 7221 side. The cross section of the fresh water inlet passage 72215 is circular, and the diameter is significantly smaller than the diameter of the seawater passage.

[0057] The drainage air passage 72216 extends along the height direction of the second main body part 7221B, from the upper surface of the hydraulic end valve box 7221 to the vicinity of the plunger movable cavity 72214. The cross section of the drainage air passage 72216 is circular, and the diameter is close to the diameter of the fresh water inlet passage 72215, and has a drainage air port 72216a at the upper surface of the hydraulic end valve box 7221.

[0058] The high pressure return passage 72217 is used to provide water pressure further increased to the rear part of the plunger 7222, and the structure of the high pressure return passage 72217 will be described in detail below in combination with the structure of the plunger 7222.

[0059] Since a large amount of fresh water is also obtained through the reverse osmosis treatment in the seawater desalination system, the fresh water can be used for lubrication and cooling of the plunger. For example, the system can include a fresh water tank for storing fresh water, the fresh water inlet port 72215a is connected to the outlet of the fresh water tank through a pipeline, the drainage air port 72216a is connected to a drainage tank through a pipeline, and the like.

[0060] The plunger 7222 is generally cylindrical in whole, and is arranged in the plunger movable cavity 72214 in a reciprocating manner. The plunger 7222 includes a plunger barrel 72221, a plunger fixing part 72222, and a plunger base part 72223.

[0061] The plunger barrel 72221 is hollow cylindrical, has an axial through mounting hole in the middle part, the outer diameter of the front half of the plunger barrel 72221 is larger than the outer diameter of the rear half, a step structure is formed in the axial middle part of the plunger barrel 72221, and a ring of rear end stress surfaces 7222A is formed in the axial middle part. The rear end stress surfaces 7222A are uniform in width and coaxial with the plunger 7222, i.e. the circular ring surface is perpendicular to the axial direction of the plunger 7222. The outer diameter of the front half of the plunger barrel 72221 is close to the inner diameter of the plunger movable cavity, and the outer diameter of the rear half is significantly smaller than the inner diameter of the plunger movable cavity, so that an annular gap is formed between the rear half and the plunger movable cavity.

[0062] In the alternative, the plunger barrel 72221 can also adopt other structures, such as a middle part with a wider annular groove, one side wall of the annular groove forming a circular annular rear end stress surface 7222A, or the plunger barrel 72221 rear end having other structures, as long as it does not affect the middle part having an exposed annular rear end stress surface 7222A, and the rear end stress surface 7222A has a space behind it (corresponding to the plunger stroke).

[0063] The plunger base 72223 is connected to the power output component of the power end 723 by a floating connection assembly 7224. One end of the plunger base 72223 has a thicker flange 72223a, and the other end is stepped and has a threaded hole in the middle.

[0064] The plunger fixing member 72222 is a fixed bolt, which is threaded in the plunger barrel 72221, and the screw rod end is threaded with the plunger base 72223, and the nut is located outside one end of the plunger barrel 72221 and abuts against the outer end face of the one end of the plunger barrel 72221, thereby fixing the plunger barrel 72221. The outer end face of the plunger base 72223 is a plane, and the plane is perpendicular to the axial direction of the plunger 7222. In this embodiment, the other end of the plunger fixing member 72222 opposite to the nut has a flange, and the plunger barrel 72221 is clamped between the nut and the flange.

[0065] The front end of the plunger 7222 has a front end stress surface 7222B, which is opposite to the direction of the rear end stress surface 7222A. The front end stress surface 7222B includes the circular annular face of the front end of the plunger barrel 72221 and the plane of the front end (nut end) of the plunger fixing member 72222. The area of the front end stress surface 7222B is substantially equal to the cross-sectional area of the front half of the plunger 7222.

[0066] In this embodiment, the plunger 7222 is three, and the pressurizing flow channel 72213 and the plunger movable cavity 72214 are also three respectively. The three plungers 7222 are arranged at equal intervals along the length direction of the first main body component 7221A. In operation, the three plungers 7222 alternately reciprocate.

[0067] Figure 5 is a perspective view of the one-way valve in this embodiment, Figure 6 is a structural exploded view of the one-way valve in this embodiment.

[0068] As shown in Figure 5 and Figure 6 , the one-way valve 7223 includes a valve cover 72231, a valve seat 72232, a valve core 72233, and a reset spring (not shown in the figure).

[0069] The valve cover 72231 is substantially in the shape of a cylindrical cap, with an open bottom and a circular annular mating protrusion 72231a at the top for mating with the cap sealing assembly to seal the end periphery. A water outlet hole 72231b is formed in the middle of the top. The side of the valve cover 72231 has a plurality of water passing holes 72231c evenly distributed along the circumference, which are strip-shaped holes with circular ends, with the length direction of the strip-shaped holes consistent with the axial direction of the valve cover 72231. A flow guide protrusion 72231d is formed on the inner surface of the valve cover 72231 between two adjacent water passing holes 72231c, protruding towards the central axis. The lower end of the inner surface of the valve cover 72231 has internal threads.

[0070] The valve seat 72232 is substantially in the shape of a cylinder, with a smaller outer diameter at the upper end and external threads for threaded connection with the valve cover 72231. The outer diameter of the middle section is substantially the same as that of the lower section of the valve cover 72231, and the lower end has a ring groove for mounting a sealing ring. The upper end of the valve seat 72232 has an inclined annular sealing surface on the inner periphery. The middle of the valve seat 72232 has a water inlet hole 72232a.

[0071] The valve core 72233 is an asymmetrically structured special-shaped part, including a valve core body 72233A and a flow guide part 72233B formed integrally. The valve core body 72233A is substantially in the shape of a disc, with an inclined annular surface at one end edge matching the annular sealing surface of the valve seat 72232. The flow guide part 72233B extends from the one end of the valve core body 72233A for guiding seawater. The flow guide part 72233B includes three plate-shaped parts 72234, each substantially in the shape of a rectangular plate with the face direction parallel to the axial direction of the valve core 72233, and the corner portions are rounded. One edge of the three plate-shaped parts 72234 is connected, and the three plate-shaped parts 72234 are spaced 120 degrees apart. The other end of the valve core body 72233A has a protrusion for limiting the spring.

[0072] One end of the reset spring is sleeved on the protrusion at one end of the valve core 72233, and the other end is embedded in the circular groove in the valve cover 72231, for pushing the valve core 72233 towards the valve seat 72232. When the valve core 72233 is pressed against the valve seat 72232, the water inlet hole 72232a and the water outlet hole 72231b are blocked. When the valve core 72233 moves a small distance against the spring force, an annular channel is formed between the valve core 72233 and the valve seat 72232, and the water inlet hole 72232a and the water outlet hole 72231b are connected.

[0073] As Figure 2As shown, part of the one-way valve 7223 is arranged as the water inlet valve 7223A at one end of the pressurized flow channel 72213 close to the high-pressure water inlet flow channel 72211, the axial direction of the water inlet valve 7223A is consistent with the length direction of the first body part 7221A, the valve seat 72232 thereof faces the high-pressure water inlet flow channel 72211, and one end of the valve cover 72231 faces the water inlet valve maintenance opening 72213b.

[0074] The other one-way valve 7223 is arranged as the water outlet valve 7223B at one end of the pressurized flow channel 72213 close to the high-pressure water outlet flow channel 72212, the axial direction of the water outlet valve 7223B is consistent with the height direction of the first body part 7221A, the valve seat 72232 thereof faces the middle of the pressurized flow channel 72213, and one end of the valve cover 72231 faces the water outlet valve maintenance opening 72213a.

[0075] The plunger sealing assembly is used to seal between the plunger 7222 and the plunger movable cavity 72214 to prevent seawater from entering the power end 723 along the cavity. The plunger sealing assembly includes a front-end high-pressure sealing assembly 72251, a front-end low-pressure sealing assembly 72252, a rear-end high-pressure sealing assembly 72253, and a rear-end low-pressure sealing assembly 72254. Among them, the front-end high-pressure sealing assembly 72251 and the front-end low-pressure sealing assembly 72252 are arranged between the front half of the plunger 7222 (i.e. the larger outer diameter section) and the plunger movable cavity 72214, and the rear-end high-pressure sealing assembly 72253 and the rear-end low-pressure sealing assembly 72254 are arranged between the rear half of the plunger 7222 and the plunger movable cavity 72214.

[0076] The plunger sealing assembly divides the plunger movable cavity 72214 into multiple cavities, including a front cavity 72214a located in front of the front-end high-pressure sealing assembly 72251, and a rear cavity 72214b located between the front-end low-pressure sealing assembly 72252 and the rear-end high-pressure sealing assembly 72253.

[0077] Figure 7 is Figure 2 An enlarged view of the inner part of the middle frame B.

[0078] As Figure 2 and Figure 7 As shown, the floating connection assembly 7224 includes a connecting part 72241, a positioning part 72242, a spherical part 72243, and a driving assembly.

[0079] The connecting part 72241 is generally cylindrical in shape, with a smaller outer diameter at one end of its axial direction, and the other end of its axial direction has a receiving groove 72241b with a circular cross section. The groove bottom of the receiving groove 72241b has a further recessed mounting groove 72241c with a circular cross section. The inner wall of the receiving groove 72241b is provided with an internal thread.

[0080] The spherical member 72243 is generally in the shape of a flat cylinder, with a spherical surface at one axial end and a flat surface perpendicular to the axial direction at the other axial end. The spherical member 72243 is fitted into the installation groove 72241c, with the spherical surface facing the plunger.

[0081] The positioning member 72242 is generally in the shape of a cylinder, with a smaller outer diameter at both ends than the middle portion. One end of the positioning member 72242 is fitted into one end of the plunger movable cavity 72214, with the low-pressure sealing assembly 72252 disposed between the one end and the plunger. The other end of the positioning member 72242 is fitted into the cavity of one end of the power end 723. The positioning member 72242 has a movable cavity formed therein, and the inner wall has multiple annular protrusions. The positioning member 72242 is sleeved on one end of the plunger 7222 and the connecting member 72241, and there is a gap between the outer wall of the connecting member 72241 and the inner wall of the positioning member 72242. The corresponding annular protrusions guide the plunger 7222 and the connecting member 72241 to maintain coaxiality. The upper end of the positioning member 72242 has a circular through hole 72242a extending along the height direction of the first main body member 7221A. The box connecting member 7221C has a through hole corresponding to the through hole 72242a, which can form an air flow channel 72218 in combination with the through hole 72242a.

[0082] The driving assembly includes a first driving member 72244 and a second driving member 72245 that cooperate with each other. The first driving member 72244 is in the shape of a ring, with external threads on the outer periphery and a step formed on the inner periphery. The first driving member 72244 is threadedly connected to one end of the positioning member 72242 and sleeved on the plunger base member 72223. The second driving member 72245 is in the shape of a ring and smaller in size than the first driving member 72244. The second driving member 72245 is sleeved on the plunger base member 72223 and located beside a flange 72223a of the plunger base member 72223.

[0083] When the power output member of the power end 723 moves towards the plunger 7222, the positioning member 72242 fixedly connected thereto moves, and the positioning member 72242 pushes the spherical member 72243, which abuts against the bottom surface of the plunger and pushes the plunger 7222 to move. Through the spherical surface, the force provided by the power output member is always maintained on the central axis of the plunger 7222.

[0084] When the power output member moves in the opposite direction, the positioning member 72242 fixedly connected thereto and the driving assembly move, and the second driving member 72245 abuts against the flange of the plunger base member 72223 and pulls the plunger 7222 in the opposite direction.

[0085] The positioning component 72242 has an air cavity. When the plunger 7222 moves, the air in the cavity can be discharged to the outside through the airflow channel 72218 or drawn in from the outside, thereby maintaining air pressure balance.

[0086] The flow guiding component 7226 is used to guide fresh water to the outer peripheral surface of the plunger cylinder 72221, thereby using fresh water to lubricate and cool the plunger cylinder 72221.

[0087] Figure 8 This is a perspective view of the flow guiding component in this embodiment.

[0088] like Figure 8 As shown, the flow guiding component 7226 is generally annular, with an annular groove on its outer circumference and an inner circumference, namely an outer annular groove 72261 and an inner annular groove 72262. The cross-section of each groove is a flattened rectangle along the circumference of the flow guiding component 7226. The flow guiding component 7226 also has multiple radially extending and penetrating flow guiding holes 72263, that is, the flow guiding holes 72263 connect the outer annular groove 72261 and the inner annular groove 72262. The cross-section of the flow guiding holes is circular, and the multiple flow guiding holes 72263 are evenly distributed along the circumference of the flow guiding component 7226. In this embodiment, there are six flow guiding holes 72263.

[0089] like Figure 3 As shown, the flow guiding component 7226 is fitted onto the plunger cylinder 72221, with its inner circumferential edge roughly in contact with the surface of the plunger cylinder 72221. An inner circumferential groove 72262 forms a flow channel with the plunger cylinder 72221, and the outer circumferential groove 72261 communicates with the inlet freshwater flow channel 72215 and the outlet airflow channel 72216, respectively. The flow guiding component 7226 contacts and is sealed by the rear high-pressure sealing assembly 72253 and the rear low-pressure sealing assembly 72254 on both axial sides, respectively. Furthermore, as the plunger 7222 reciprocates, different positions on the outer circumferential surface of the plunger cylinder 72221 are located at the flow guiding component 7226. Therefore, fresh water enters through the fresh water inlet 72215a, passes sequentially through the fresh water inlet channel 72215, the outer circumferential groove 72261, and the guide hole 72263 into the inner circumferential groove 72262, and contacts the outer circumferential surface of the plunger cylinder 72221, thereby lubricating and cooling the plunger cylinder 72221. Then, the fresh water passes sequentially through the guide hole 72263, the outer circumferential groove 72261, and the drain gas flow channel 72216, and is discharged from the drain gas flow channel 72216. The drain gas flow channel 72216 opens vertically upwards, so that even if air bubbles are present in the fresh water, the air in the bubbles can be discharged through the drain gas flow channel 72216.

[0090] like Figure 2As shown, the power end 723 mainly comprises a power end valve box 7231 and a plurality of crank connecting rods arranged inside the valve box. The crank connecting rod comprises a crankshaft 7232, a connecting rod 7233 (a power output component), a crosshead and the like, wherein one end of the connecting rod 7233 is threadedly connected with the connecting component 72241. The crankshaft 7232 rotates to drive the connecting rod 7233 to reciprocate along the axial direction, thereby driving the plunger 7222 to reciprocate through the floating connection assembly 7224.

[0091] The structure of the power end 723 is known in the art, and thus will not be described in detail.

[0092] The pump driving mechanism 724 comprises a servo motor 7241, a speed reducer box 7242, a shaft coupling 7243 and a shaft coupling housing 7244.

[0093] The speed reducer box 7242 is fixed on one side of the power end 723, and a transmission shaft in the speed reducer box 7242 is directly connected with the rotating shaft of the crankshaft in the power end 723, and the shaft coupling is externally arranged, so that the speed reducer box 7242 is greatly miniaturized.

[0094] The servo motor 7241 is horizontally arranged beside one side of the speed reducer box 7242, and the output shaft thereof is connected with the transmission shaft of the speed reducer box 7242 through the shaft coupling. Such an arrangement makes the overall height of the two-stage high-pressure pump 72 very small, and is a horizontal high-pressure pump.

[0095] The shaft coupling housing 7244 is in the form of a curved plate, and is arranged outside the shaft coupling 7243 and surrounds the shaft coupling 7243.

[0096] In an alternative, a conventional speed reducer box can also be used when the space allows, or according to the size requirement of the space in the container, a conventional speed reducer box can also be used, and the servo motor is vertically arranged above the speed reducer box, thereby reducing the lateral size of the two-stage high-pressure pump and making it a vertical high-pressure pump.

[0097] In operation, the servo motor 7241 drives the crankshaft 7233 to rotate through the speed reducer box 7242, drives the connecting rod 7232 to reciprocate along the horizontal direction, and further drives the plunger 7222 to reciprocate.

[0098] When the plunger 7222 moves backward (towards the power end 723), the seawater pressure in the pressurized flow passage 72213 decreases, the valve core 72233 of the outlet valve 7223B still remains pressed on the valve seat 72232, and the valve core 72233 of the inlet valve 7223A is moved away from the valve seat under the action of the pressure difference, so as to realize the extraction of concentrated seawater from the high-pressure inlet 72211a.

[0099] When the plunger 7222 moves forward (towards the pressurizing flow channel 72213), the pressure of the seawater in the pressurizing flow channel 72213 increases, the valve core 72233 of the inlet valve 7223A is pressed against the valve seat 72232, a high-pressure area is formed in the pressurizing flow channel 72213, when the seawater pressure reaches the predetermined use pressure, the valve core 72233 of the outlet valve 7223B is separated from the valve seat under the action of the pressure difference, and the high-pressure concentrated seawater with the specified water pressure is pumped to the high-pressure outlet 72211b.

[0100] In addition, an overflow safety valve (not shown in the figure) is arranged in communication with the high-pressure outlet flow channel 72212, when the water pressure in the high-pressure outlet flow channel 72212 exceeds the predetermined safety pressure, part of the flow can be released to the outside by the overflow safety valve, so that the secondary high-pressure pump 72 can operate safely and stably.

[0101] As shown in FIGS. Figure 3 and Figure 4 The high-pressure return channel 72217 in the fluid end 722 is L-shaped, one end of which is in communication with the upper end of the pressurizing flow channel 72213, that is, in communication with the high-pressure outlet flow channel 72212 through the water passage hole 72231c in the upper part of the outlet valve 7223B. The other end of the high-pressure return channel 72217 is in communication with the rear cavity 72214b of the plunger movable cavity 72214. The cross section of the high-pressure return channel 72217 is circular, and from the above-mentioned one end to the other end, the high-pressure return channel 72217 first extends along the width direction of the first main part 7221A, and then extends along the height direction of the first main part 7221A. The inner diameter of the channel part extending along the width direction of the first main part 7221A is relatively larger.

[0102] The concentrated seawater after further pressurization can be returned to the rear cavity 72214b through the high-pressure return channel 72217, so that the high pressure of the pressurized concentrated seawater acts on the rear end stress surface 7222A of the plunger 7222, thereby balancing the high pressure received by the front end stress surface 7222B of the plunger 7222, and further enabling the secondary high-pressure pump 72 to pressurize the concentrated seawater to the ideal pressure with smaller power.

[0103] Specifically, when the plunger 7222 starts to move forward (towards the corresponding pressurizing flow channel 72213) to extrude the liquid in the cavity, the water pressure at the front end stress surface 7222B of the plunger 7222 (that is, the water pressure of the seawater in the pressurizing flow channel 72213 and the front cavity 72214a) is the input water pressure P 供水 of the concentrated seawater entering from the high-pressure inlet 72211a. The rear cavity 72214b is in communication with the high-pressure outlet flow channel 72212 through the high-pressure return channel 72217, so the water pressure at the rear end stress surface 7222A of the plunger 7222 is the output water pressure P 出水 . The area S前 The area S of the rear bearing surface 7222A 后 The proportions make the following equation true:

[0104] F = S 前 ×P 供水 =S 后 ×P 出水

[0105] Taking an input water pressure P of 5 MPa and an output water pressure P of 10 MPa as an example, to make the above formula true, the area S of the rear bearing surface 7222A (annular surface) is half the area S of the front bearing surface 7222B. After satisfying the above formula, the plunger 7222 only needs to bear an additional force along the required pressure difference (i.e., 10 MPa - 5 MPa = 5 MPa) in the axial direction, thereby achieving energy saving, theoretically saving nearly 50% of energy.

[0106] When the input water pressure and output water pressure are different, the areas of the rear bearing surface 7222A and the front bearing surface 7222B can be adjusted accordingly according to the above formula.

[0107] Figure 9 This is a three-dimensional representation of the maintenance status of the secondary high-pressure pump in this embodiment. Figure 1 .

[0108] like Figure 1 and Figure 9 As shown, multiple inlet valve access openings 72213b are located on the front face of the hydraulic valve box 7221. Each inlet valve access opening 72213b is sealed by a cover sealing assembly 7221D and is fitted with a rectangular plate-shaped cover 7221C by multiple fasteners (bolts). After removing the cover 7221C and the cover sealing assembly 7221D, the inlet valve access opening 72213b is exposed. The diameter of the inlet valve access opening 72213b and the inlet valve access opening 72213b at one end is compatible with the inlet valve 7223A. Therefore, each inlet valve 7223A can be easily removed through the inlet valve access opening 72213b for inspection and replacement. The outlet valve 7223B is handled similarly.

[0109] Figure 10 This is a three-dimensional representation of the maintenance status of the secondary high-pressure pump in this embodiment. Figure 2 .

[0110] like Figure 1 and Figure 10As shown, after the plurality of long bolts used to fix the first body part 7221A are removed, the first body part 7221A (including the one-way valve therein) can be removed as a whole, and the plurality of plungers 7222 can be exposed. Then, by rotating and removing the plunger fixing part 72222 together with the plunger cylinder 72221, the plunger cylinder 72221 can be repaired or replaced.

[0111] In addition, as shown in Figure 1 and Figure 2 The secondary high-pressure pump 72 further includes an accumulator 7251, an electronic pressure gauge 7252, and a mechanical pressure gauge 7253 (pressure meter).

[0112] The cover part 7221D installed at the outlet valve maintenance opening 72213a and the corresponding cover sealing assembly 7221E further have a through hole in communication with the high-pressure outlet flow channel 72212, which can be used to install the accumulator and the pressure gauges.

[0113] The accumulator 7251 has a tubular lower part installed on one of the cover parts 7221D and a spherical upper part. An accumulator cavity in communication with the outlet flow channel 72212 is formed inside the accumulator 7251, which is filled with gas, preferably inert gas, such as nitrogen. In use, part of the concentrated seawater will enter the inside of the accumulator cavity under pressure, with the liquid surface located at about the middle of the accumulator cavity, and the compressed gas at the top of the accumulator cavity.

[0114] The accumulator 7251 can stabilize the output water pressure. When the water pressure in the high-pressure outlet flow channel 72212 fluctuates, for example, increases, more concentrated seawater will enter the inside of the accumulator cavity, further compressing the gas in the cavity, and accordingly, the water volume in the high-pressure outlet flow channel 72212 will slightly decrease, thereby slightly reducing the output water pressure. When the output water pressure decreases, part of the concentrated seawater will be discharged from the accumulator cavity under the pressure of the compressed gas in the cavity, and accordingly, the water volume in the high-pressure outlet flow channel 72212 will slightly increase, thereby slightly increasing the output water pressure, achieving the stabilization of the output water pressure.

[0115] The electronic pressure gauge 7252 and the mechanical pressure gauge 7253 are used to detect the pressure of the seawater in the outlet flow channel 72212, i.e., the pressure of the seawater output by the secondary high-pressure pump 72. The electronic pressure gauge 7252 can provide more accurate pressure values, and in the event of a failure of the electronic pressure gauge 7252, the mechanical pressure gauge 7253 can still provide pressure values. Since the water pressure output by the secondary high-pressure pump 72 directly affects the reverse osmosis effect, it is necessary to monitor the output water pressure, and therefore, such a redundant design is very advantageous.

[0116] In the embodiment, the plunger barrel 72221 of the plunger 7222 is made of ceramic material, the plunger fixing member 72222 and the plunger base member 72223 are made of stainless steel, for example, 17-4PH stainless steel. The valve cover 72231 and the valve core 72232 of the one-way valve 7223 are made of titanium alloy, for example, TC4 titanium alloy, and the valve seat 72233 can be made of titanium alloy or stainless steel, for example, TC4 titanium alloy or 2507 stainless steel. In the hydraulic end valve box 7221, the first main body member 7221A, the second main body member 7221B and other seawater flow members are made of 2507 stainless steel, the cover member 7221D and other auxiliary non-seawater flow members such as the fixing member thereof can be made of 316L stainless steel, the power transmission members (connecting members 72241, positioning members 72242, spherical members 72243, etc.) of the plunger can be made of 2Cr13 stainless steel, the first driving member 72244 and the second driving member 72245 are made of a material with certain elasticity, for example, polyurethane (PU).

[0117] In the embodiment, the pressure of the concentrated seawater output by the first reverse osmosis module is 5Mpa-7Mpa, that is, the pressure of the high-pressure concentrated seawater input into the second high-pressure pump 72 is 5Mpa-7Mpa, the pressure of the high-pressure concentrated seawater output by the second high-pressure pump 72 is 10Mpa-12Mpa, and the flow rate requirement is 42L / min. Correspondingly, the cross-sectional area of the first half (the larger outer diameter part) of the plunger 7222 is 700mm 2 -1200mm 2 , preferably 800mm 2 -950mm 2 , and the number of plungers 7222 is 3-7; the rotating speed of the servo motor 7241 is 1000r / min, the reduction ratio of the reduction box 7242 is 2.5-3.5, that is, the rotating speed output by the reduction box 7242 is 285r / min-400r / min, and in the embodiment, the reduction ratio is 2.94. In addition, since the water pressure that the second high-pressure pump 72 needs to withstand is lower than 16Mpa, the wall thickness of the hydraulic end valve box 7221 can be maintained at 3mm-12mm, preferably 5mm-10mm, and more preferably 8mm-10mm. The overall volume of the hydraulic end valve box 7221 is 18L-40L.

[0118] Effects of the embodiment

[0119] The secondary high-pressure pump, the reverse osmosis mechanism and the seawater edible salt system provided by the embodiment have a plunger in the liquid end of the secondary high-pressure pump, and the plunger is driven to move by a servo motor and a speed reducer, that is, the pump is a displacement pump, has the advantages of large and stable flow, high energy utilization efficiency, compact structure and the like, and the servo motor is small in size and capable of achieving high-precision control compared with a traditional asynchronous motor, so that the primary high-pressure pump is significantly smaller in size under the premise of maintaining ideal flow, and is capable of achieving fast and accurate response when the system working condition changes, so that the concentrated seawater output by the reverse osmosis module is stable in quality, and is beneficial to stably and efficiently producing edible salt.

[0120] Further, the plunger has a force receiving surface towards the power end in the middle part, and the liquid end has a high-pressure return channel in communication with the high-pressure outlet water flow channel and the rear cavity of the plunger movable cavity respectively, so that the pressure (i.e. output water pressure) of the concentrated seawater further pressurized by the secondary high-pressure pump acts on the force receiving surface, partially offsets or completely balances the input water pressure received by the front end of the plunger, so that for the same output water pressure, the axial force required by the plunger of the secondary high-pressure pump is greatly reduced, so that the concentrated seawater is further pressurized with significantly lower energy consumption, and a multi-stage reverse osmosis module with low energy consumption can be realized by using the secondary high-pressure pump, multi-stage reverse osmosis is realized in the seawater edible salt system, high-concentration concentrated seawater is output, the time required for subsequent salting and other processes is shortened, and the yield and output efficiency of edible salt are improved.

[0121] In the embodiment, the rear end force receiving surface of the plunger is annular, and the area of the rear end force receiving surface and the front end force receiving surface is designed to keep the liquid pressure at the front end of the plunger and the liquid pressure at the annular surface at the rear end in force balance, so that the plunger only needs the axial force required to lift the pressure difference, and theoretically, energy saving is nearly 50% compared with the scheme without the high-pressure return channel. And the area ratio of the front end force receiving surface and the rear end force receiving surface can be adjusted to adapt to different input water pressures and output water pressures.

[0122] The pump driving mechanism includes a servo motor and a speed reducer, and the servo motor is small in size and capable of achieving high-precision control compared with an asynchronous motor, so that the secondary high-pressure pump is significantly smaller in size under the premise of maintaining ideal flow, and is capable of achieving fast and accurate response when the system working condition changes, so that the concentrated seawater output by the reverse osmosis module is stable in quality, and is beneficial to stably and efficiently producing edible salt.

[0123] Further, the cross-sectional area of the plunger is designed to be large, and the reduction gear box is designed with a corresponding reduction ratio, so that the frequency of the reciprocating motion of the plunger can be reduced while maintaining the flow rate, that is, the rotational speed of the motor and the reducer output can be reduced, thereby effectively reducing noise and vibration, and achieving energy saving effect. Since the seawater edible salt system needs to be operated for a long time or even all day, the saved electric energy will be quite significant. Moreover, according to the required output water pressure, the wall thickness of the hydraulic end valve box does not need to increase with the cross-sectional area of the plunger, which is also beneficial to the miniaturization of the two-stage high-pressure pump and the reduction of equipment cost.

[0124] Further, the reduction gear box is fixed on the power end side, and the transmission shaft of the reduction gear box is directly connected with the rotating shaft of the power end crankshaft, and the coupling is externally provided, so that the size of the reduction gear box is greatly reduced. In addition, the servo motor is horizontally arranged on one side of the reduction gear box, so that the overall height of the two-stage high-pressure pump is small, which can meet the assembly requirements in the limited space of the container.

[0125] Further, the plunger is further sleeved with a flow guide component, which can guide the fresh water to the outer peripheral surface of the plunger through the flow guide channel, so that the plunger can be lubricated and cooled by the fresh water, avoiding the problem of microcrystalline particles when using seawater, causing wear of the plunger and other components, and further improving the service life of the plunger and other components, reducing the frequency of maintenance and repair by workers. Moreover, since the primary high-pressure pump is used in the seawater edible salt system, a large amount of fresh water will also be produced after reverse osmosis treatment, so it is very convenient to introduce fresh water into the primary high-pressure pump, and no additional fresh water treatment equipment needs to be added in the system, which is a clever design of reasonable and effective use of system resources.

[0126] In the embodiment, the flow guide component has an outer peripheral ring groove, an inner peripheral ring groove and a plurality of flow guide holes, which can supply fresh water to the inner peripheral ring groove through the plurality of flow guide holes and contact the outer peripheral surface of the plunger barrel, so that the plunger barrel can be relatively more uniformly lubricated and cooled. The fresh water inlet channel cooperated with the flow guide component horizontally supplies fresh water from one side, and the water drainage gas passage vertically extends upward to the top of the valve box, so that air can be automatically discharged through the water drainage gas passage, avoiding the accumulation of air in the valve box to affect the normal operation of the plunger.

[0127] Further, the plunger and the connecting rod of the crankshaft are connected through a floating connection assembly. When the connecting rod moves forward, the outer end surface of the spherical push plunger base is pushed, and due to the dimensional tolerance of each component, it is difficult to ensure that the connecting rod of the crankshaft and the plunger are always coaxial. Using a conventional fixed connection method, the dimensional tolerance will cause a certain eccentricity, which will further cause greater vibration and wear of the plunger. In the embodiment, the plunger is pushed by the spherical surface, so that the force of the connecting rod of the crankshaft always acts on the central axis of the plunger, further reducing vibration and improving the service life of the plunger.

[0128] Further, the plunger barrel of the plunger is made of ceramic material, and the valve core of the one-way valve is made of titanium alloy, so that the components can be prevented from being corroded by seawater, and the wear of the components subjected to high-frequency movement can be reduced, thereby reducing the frequency of maintenance and repair. In the hydraulic end, the seawater flow components are made of 2507 stainless steel, and the auxiliary flow components are made of 316L stainless steel, so that the system can be stably operated for a longer time, and the overall cost of the secondary high-pressure pump is kept low.

[0129] Further, one side of the water inlet valve and the water outlet valve is respectively provided with a corresponding maintenance opening, and the maintenance opening is exposed by removing the corresponding cover and cover sealing assembly, and then the water inlet valve and the water outlet valve can be conveniently inspected or replaced through the maintenance opening. In addition, the first main body part can be completely removed, so that at least the front end of the plunger is exposed, and then the plunger barrel can be conveniently inspected or replaced. These designs make the one-way valve, plunger barrel and other components subjected to high-frequency movement and relatively more prone to wear can be conveniently maintained and replaced, thereby reducing the frequency of overall repair of the secondary high-pressure pump.

[0130] Further, the accumulator filled with inert gas is arranged on the hydraulic end and communicates with the water outlet flow channel of the hydraulic end, so that the water outlet pressure can be self-adaptively adjusted by using compressed gas, so that the water outlet pressure is kept more stable, thereby being beneficial to keeping the quality of the concentrated seawater produced stable, and the adjustment of the water outlet pressure can be realized by simple principle and structure, and the adjustment effect is good and complex electric control design is not needed.

[0131] Further, the electronic pressure gauge and the mechanical pressure gauge are arranged on the hydraulic end and communicate with the water outlet flow channel of the hydraulic end, the electronic pressure gauge can provide more accurate water outlet pressure values, and when the electronic pressure gauge fails, the mechanical pressure gauge can provide relatively accurate water outlet pressure values. Through such a redundant design, the situation that the water outlet pressure cannot be obtained due to failure can be avoided, real-time monitoring of the water outlet pressure is kept, so that the effect of multi-stage reverse osmosis filtration can be guaranteed.

[0132] The above embodiments are only used for illustrating the specific implementation mode of the utility model, and the utility model is not limited to the description range of the above embodiments, and the person skilled in the art should understand that the utility model is not limited by the above embodiments, and the above embodiments and the description in the specification only illustrate the principle of the utility model, under the premise of not departing from the spirit and range of the utility model, the utility model will have various changes and improvements, and these changes and improvements all fall within the scope of the utility model claimed. The protection scope of the utility model is defined by the appended claims and their equivalents.

Claims

1. A two-stage high-pressure pump, installed in at least the second-stage reverse osmosis module of a seawater-to-salt production system, for further pressurizing concentrated seawater that has been pressurized by the previous stage reverse osmosis module, characterized in that, include: The hydraulic end is used to pressurize the concentrated seawater; The power end is used to provide power to the hydraulic end; The gearbox is connected to the power end; as well as The servo motor is connected to the gearbox. The hydraulic end includes: The hydraulic end valve box has a high-pressure outlet channel for outputting the further pressurized concentrated seawater, a plunger movement chamber, and a high-pressure return channel; and A plunger is reciprocally disposed in the plunger's movable cavity, the middle of which has a rear-end force-receiving surface facing the power end. The high-pressure return channel is connected to the high-pressure water outlet channel and the plunger movable cavity, so that the pressure of the concentrated seawater after further pressurization acts on the rear force-bearing surface.

2. The two-stage high-pressure pump according to claim 1, characterized in that: in, The end face of one axial end of the plunger is the front force-bearing surface, which is set in the opposite direction to the rear force-bearing surface. The plunger has a stepped middle section and a ring-shaped rear force-bearing surface. The ratio of the area of ​​the rear bearing surface to the area of ​​the front bearing surface corresponds to the ratio of the pressure of the concentrated seawater to the pressure of the further pressurized concentrated seawater. The area of ​​the front-end force-bearing surface is 700 mm². 2 ~1200mm 2 , The wall thickness of the hydraulic end valve box is 3mm to 12mm.

3. The two-stage high-pressure pump according to claim 1, Its features are: The power end has a power output component that moves along the reciprocating motion direction. The hydraulic end also includes a floating connection assembly, which comprises: A connecting component, one end of which is fixed to the power output component, and the other end of which has a receiving groove. The middle part of the bottom surface of the receiving groove is spherical, which is used to abut against one end of the plunger when the power output component moves toward the plunger, so that the thrust output by the power output component is kept acting on the central axis of the plunger. A positioning component is fitted onto the flanged end of the plunger and the connecting component; and A sealing and limiting component is fixed at the opening of the receiving groove to limit the end of the plunger with the flange and to seal the connection component and the plunger.

4. The two-stage high-pressure pump according to claim 1, Its features are: The plunger includes a plunger cylinder made of ceramic material. The hydraulic valve box has independent seawater and freshwater channels. The seawater channel includes the high-pressure outlet channel, the high-pressure return channel, and the plunger movement chamber. The hydraulic end also includes: A flow guiding component, sleeved on the plunger and closer to the power end relative to the force-bearing surface, has a flow guiding channel communicating with the freshwater channel for guiding freshwater from the freshwater channel to the outer circumferential surface of the plunger, thereby lubricating and cooling the plunger; and A flow guiding and sealing assembly is disposed on both sides of the flow guiding component to seal the two sides of the flow guiding component with the plunger.

5. The two-stage high-pressure pump according to claim 1, characterized in that: in, The power end includes a power end valve box. The gearbox is located on one side of the power-end valve box. The servo motor is horizontally mounted on one side of the gearbox, and its output end is connected to the input end of the gearbox via a coupling. The hydraulic valve box also has multiple mounting holes for detection components that communicate with the high-pressure water outlet channel, for mounting accumulators, electronic pressure gauges, and mechanical pressure gauges, respectively. The accumulator is used to stabilize the outlet water pressure and has an inner cavity that communicates with the high-pressure outlet water channel and is filled with gas.

6. The two-stage high-pressure pump according to claim 1, Its features are: The plunger includes a plunger cylinder made of ceramic material. The hydraulic valve box has independent seawater and freshwater channels. The seawater channel includes the high-pressure outlet channel, the high-pressure return channel, and the plunger movement chamber. The hydraulic end also includes: A flow guiding component, sleeved on the plunger and closer to the power end relative to the force-bearing surface, has a flow guiding channel communicating with the freshwater channel for guiding freshwater from the freshwater channel to the outer circumferential surface of the plunger, thereby lubricating and cooling the plunger; and A flow guiding and sealing assembly is disposed on both sides of the flow guiding component to seal the two sides of the flow guiding component with the plunger.

7. The two-stage high-pressure pump according to claim 1, characterized in that: in, The hydraulic end also has a high-pressure water inlet channel communicating with the plunger's movable chamber. The hydraulic end also includes multiple check valves. The one-way valve includes an inlet valve and an outlet valve, which are respectively disposed in the high-pressure inlet channel and the high-pressure outlet channel. The one-way valve includes a valve body, a titanium alloy valve core disposed in the valve body, and a reset component for resetting the valve core. The valve core has: The valve core body is movably disposed within the internal cavity of the valve body; and A rear guide portion is formed at one end of the valve core body located upstream of the concentrated seawater flow direction, for guiding the concentrated seawater so that the pressure generated by it acts evenly on the surface of the valve core body.

8. The two-stage high-pressure pump according to claim 7, characterized in that: in, The hydraulic end valve box includes a main body component, multiple cover components, and multiple cover seals. There are multiple plungers, and multiple sets of inlet and outlet valves, each corresponding to one of the plungers. The main body component of the box has: The inlet valve access opening is connected to the high-pressure inlet channel, and its diameter corresponds to the diameter of the inlet valve; and The access opening for the outlet valve is connected to the high-pressure water outlet channel, and its diameter corresponds to the diameter of the outlet valve. Multiple covers and multiple cover seals are detachably installed at the access openings of the inlet valve and the outlet valve, respectively.

9. A reverse osmosis mechanism, installed in a seawater-to-salt production system, characterized in that, include: Multi-stage reverse osmosis module, The reverse osmosis module at least in the second stage includes: A secondary high-pressure pump is used to further pressurize the concentrated seawater pressurized by the previous stage reverse osmosis module; and The reverse osmosis section is used to perform reverse osmosis treatment on the further pressurized concentrated seawater, thereby separating further concentrated concentrated seawater from the concentrated seawater. The secondary high-pressure pump is the secondary high-pressure pump according to any one of claims 1-8.

10. A system for producing edible salt from seawater, characterized in that, include: A reverse osmosis unit is used to treat seawater by reverse osmosis, thereby separating concentrated brine from the seawater. The reverse osmosis mechanism is the reverse osmosis mechanism as described in claim 9.

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