Reverse osmosis water production pipe, multi-stage reverse osmosis system and low-energy-consumption high-power concentration process

Abstract

The invention relates to the field of water treatment, and particularly discloses a reverse osmosis water production pipe, a multi-stage reverse osmosis system and a low-energy-consumption high-power concentration process, the reverse osmosis water production pipe comprises a water production pipe body, a central pipe, a reverse osmosis membrane element, a plugging piece and a water production net; the other end of the water production pipe body is connected with a discharge pipe; the central pipe penetrates through the water producing pipe body, a communicating hole communicating the inner side and the outer side of the central pipe is formed in the pipe wall of the central pipe, and the central pipe is used for providing a produced water outflow channel; the reverse osmosis membrane element is wound on the central pipe and is used for carrying out reverse osmosis separation on introduced wastewater to form produced water and concentrated water; the plugging piece is arranged in the central pipe and used for dividing the central pipe into a plurality of first water producing sections and second water producing sections which are not communicated with one another, the first water producing sections are used for discharging produced water, and the second water producing sections are communicated with the low-pressure pump; the water producing net is tightly attached to the outer wall of the central pipe, covers the communicating holes and is connected with different water producing sections blocked by the blocking pieces. The reverse osmosis membrane has the effects of improving the reverse osmosis efficiency and reducing the reverse osmosis cost.

Description

Technical Field

[0001] The present application relates to the technical field of water treatment, and in particular to a reverse osmosis water production pipe, a multi-stage reverse osmosis system and a low-energy consumption high-multiple concentration process. Background Art

[0002] A large amount of industrial wastewater is generated in the process of steel production, coal mining, chemical production, petroleum smelting and other industrial production. These industrial wastewaters contain a large amount of monovalent salts, divalent salts and non-degradable organic matter. If they are directly discharged, they will cause a lot of pollution to the environment. Therefore, after the industrial wastewater is generated, it needs to be treated to meet the discharge standards before it can be discharged.

[0003] Common ways to treat industrial wastewater include physical treatment, chemical treatment, biological treatment, membrane separation technology treatment, advanced oxidation technology treatment, etc. Among the membrane separation technology treatment methods, reverse osmosis treatment is a commonly used method to remove salt and residual organic matter from industrial wastewater.

[0004] The existing reverse osmosis treatment method is to pass industrial wastewater through the water production pipe, and then divide the industrial wastewater into concentrated water and relatively pure produced water after passing through the reverse osmosis membrane assembly on the water production pipe. The existing reverse osmosis technology has the problem that when industrial wastewater is reverse osmosis treated, the osmotic pressure difference on both sides of the reverse osmosis membrane is too large, resulting in high energy consumption, reduced reverse osmosis efficiency, and high reverse osmosis cost. Summary of the invention

[0005] In order to improve the reverse osmosis efficiency and reduce the reverse osmosis cost, the present application provides a reverse osmosis water production pipe, a multi-stage reverse osmosis system and a low-energy consumption high-multiple concentration process.

[0006] To achieve the above objectives, this application adopts the following technical solutions: On one hand, the present application provides a reverse osmosis water production pipe, comprising: The water production pipe body has a water inlet pipe connected to one end and a discharge pipe connected to the other end; A central tube is inserted into the water production tube body, a connecting hole is provided on the wall of the central tube to connect the inner and outer sides of the central tube, and the central tube is used to provide a channel for the water production to flow out; A reverse osmosis membrane element is wound around the central tube and is used to reversely osmosis separate the introduced wastewater into produced water and concentrated water; A plugging member is arranged inside the central tube, and is used to divide the central tube into a plurality of first water production sections and second water production sections which are not connected to each other, wherein the first water production sections are used to discharge produced water, and the second water production sections are connected to a low-pressure pump, and the low-pressure pump is used to transport high-concentration produced water; A water production network is closely attached to the outer wall of the central tube and covers the connecting hole, and the water production network connects the first water production section and the second water production section blocked by the plugging member.

[0007] By adopting the above technical scheme, when industrial wastewater is treated, the industrial wastewater is input from the water inlet pipe, so that the industrial wastewater passes through the reverse osmosis membrane element inside the water production pipe body to form product water and concentrated water. The product water passes through the water production network and enters the first water production section of the central pipe through the connecting hole outside the central pipe for discharge. At this time, the low-pressure pump transports high-concentration product water to the second water production section. Under the action of the plugging component, the high-concentration product water flows out from the connecting hole through the water production network into the first water production section, thereby increasing the concentration of the product water in the first water production section, thereby reducing the osmotic pressure difference on both sides of the reverse osmosis membrane element, facilitating the product water to pass through the reverse osmosis membrane element, accelerating the reverse osmosis efficiency, and reducing the reverse osmosis cost.

[0008] Optionally, a reverse osmosis water production pipe further includes a flow guide, which is rotatably arranged in the reverse osmosis membrane element, and is used to guide the water flow in the reverse osmosis membrane element to flow around the central tube in a rotational manner.

[0009] By adopting the above technical solution, when industrial wastewater passes through the osmotic membrane element, the guide member guides the water flow in the reverse osmosis membrane element to rotate around the central tube, so that the impurities in the water flow in the reverse osmosis membrane element move away from the central tube due to the centripetal force, thereby reducing the water flow concentration in the direction close to the central tube, reducing the osmotic pressure difference on both sides of the industrial wastewater during reverse osmosis, facilitating the reverse osmosis of industrial wastewater, and accelerating the reverse osmosis efficiency.

[0010] Optionally, the guide member is composed of a plurality of rotationally arranged guide plates, and different guide plates are arranged in parallel.

[0011] By adopting the above technical solution, the rotatably arranged guide plates guide the water flow to move along the guide plates, so that the water flow rotates around the direction of the central tube. At the same time, by arranging a number of guide plates, the water flow is divided into a number of small flows, which facilitates the guidance of the flow direction of the water flow.

[0012] Optionally, the reverse osmosis membrane element includes a fresh water barrier and a concentrated water barrier, and the fresh water barrier and the concentrated water barrier are alternately wound around the central tube.

[0013] By adopting the above technical solution, the reverse osmosis membrane elements are arranged alternately through the fresh water barrier and the concentrated water barrier, thereby increasing the reverse osmosis area, accelerating the reverse osmosis rate and making the water flow separation more thorough.

[0014] Optionally, the concentrated water barrier includes a filter membrane and a concentrated water separator, and the filter membrane is folded in half and clamps the concentrated water separator.

[0015] By adopting the above technical solution, the stability of the concentrated water barrier is increased, the probability of sticking between the filter membranes is reduced, and the filter membranes are separated by the concentrated water separator, so that the incoming water is evenly distributed between the filter membranes, thereby improving the filtration efficiency of the concentrated water barrier.

[0016] A second aspect of the present application provides a multi-stage reverse osmosis system, which is composed of a plurality of reverse osmosis water production pipes connected in sequence, wherein the discharge pipe of the preceding reverse osmosis water production pipe is connected to the inlet pipe of the succeeding reverse osmosis water production pipe.

[0017] By adopting the above technical solution, the multi-stage reverse osmosis system can perform multi-stage reverse osmosis on industrial wastewater, thereby reducing the loss of water resources in the reverse osmosis process.

[0018] The third aspect of the present application provides a low-energy consumption high-multiple concentration process comprising the following steps: S1, pre-treating wastewater to obtain a pre-treated liquid; S2, sending the pre-treated liquid into a multi-stage reverse osmosis system for preliminary reverse osmosis treatment to obtain initial concentrated water and initial produced water discharged from the central tube; S3, sending the initial concentrated water into the nanofiltration system to obtain nanofiltration product water and nanofiltration concentrated water; S4, mixing the nanofiltration produced water and the initial produced water from the central tube to obtain intermediate produced water; S5. The intermediate produced water is subjected to reverse osmosis treatment through a reverse osmosis water production pipe outside the multi-stage reverse osmosis system to obtain final produced water.

[0019] By adopting the above technical scheme, when industrial wastewater is subjected to reverse osmosis treatment, initial concentrated water and initial produced water are obtained through preliminary reverse osmosis treatment, and the initial concentrated water is subjected to nanofiltration to obtain nanofiltration concentrated water and nanofiltration produced water. Since the concentration of nanofiltration produced water is higher than that of initial produced water, the concentration of intermediate produced water obtained by mixing nanofiltration produced water and initial produced water is increased compared to the concentration of initial produced water, thereby reducing the osmotic pressure difference of the preliminary reverse osmosis, accelerating the reverse osmosis rate, and reducing the reverse osmosis cost.

[0020] Optionally, step S4 includes: S41, the nanofiltration produced water is sent to the second water production section of the last stage reverse osmosis water production pipe of the multi-stage reverse osmosis system through a low-pressure pump; S42, the nanofiltration produced water passes through the water production network outside the central tube, bypasses the plugging component, and moves step by step to the first water production section where the initial water production is located and mixes with the initial water production.

[0021] By adopting the above technical solution, the nanofiltration produced water is mixed with the initial produced water through the water production network, thereby achieving the effect of reducing the osmotic pressure difference in the reverse osmosis process.

[0022] Optionally, step S5 includes: S51, the intermediate product water is used as the inlet water of the reverse osmosis water production pipe outside the multi-stage reverse osmosis system to undergo reverse osmosis treatment to obtain final product water and osmotic concentrated water; S52, sending the osmotic concentrate mixed with the pre-treated liquid into the first-stage water inlet pipe of the multi-stage reverse osmosis system for reverse osmosis treatment.

[0023] By adopting the above technical solution, the osmotic concentrate is mixed with the pretreatment liquid to achieve repeated reverse osmosis of the osmotic concentrate, thereby reducing the water resource loss during the reverse osmosis process and achieving high-fold concentration.

[0024] Optionally, step S1 includes: performing organic matter removal treatment and denitrification treatment on the wastewater, and performing oxidation treatment on the treated wastewater again.

[0025] By adopting the above technical scheme, the organic matter removal and denitrification treatment of the wastewater reduces the pollutancy of the wastewater, and then the wastewater is oxidized to further improve the water quality of the wastewater, making it convenient to use it as recycled water for industrial production after the wastewater is recycled.

[0026] Compared with the prior art, the present invention has at least one of the following beneficial technical effects:

[0027] 1. When treating industrial wastewater, the industrial wastewater is input from the water inlet pipe. After passing through the osmotic membrane element, the industrial wastewater forms preliminary concentrated water and preliminary produced water. The preliminary produced water enters the first produced water section of the central pipe, and the low-pressure pump transports high-concentration produced water to the second produced water section. The high-concentration produced water passes through the connecting hole and the produced water net and crosses the plugging part to mix with the initial produced water, thereby reducing the osmotic pressure difference, ultimately accelerating the reverse osmosis efficiency and reducing the reverse osmosis cost.

[0028] 2. The guide piece guides the industrial wastewater to flow around the central tube, so that the impurities in the industrial wastewater are affected by the centripetal force generated by the water flow, and the impurities gather at a position far away from the central tube, thereby reducing the reverse osmosis pressure difference near the central tube and improving the efficiency of reverse osmosis.

[0029] 3. A multi-stage reverse osmosis system formed by connecting several reverse osmosis water production pipe bodies in series can further increase the number of reverse osmosis, thereby achieving high concentration of industrial wastewater and reducing the loss of water resources in the reverse osmosis process of industrial wastewater.

[0030] 4. Through low-energy high-concentration technology, the osmotic pressure difference in the multi-stage osmosis system is reduced, so that the reverse osmosis effect can be achieved at a lower energy consumption, and by recycling the osmotic concentrated water, the concentrated water can be repeatedly reverse osmosis to achieve a high-concentration effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a schematic diagram of the external structure of the water production pipe body in the embodiment of the present application.

[0032] Figure 2 It is a schematic diagram of the external structure of the central tube of an embodiment of the present application.

[0033] Figure 3 It is a cross-sectional view of the internal structure of the central tube of an embodiment of the present application.

[0034] Figure 4 It is a schematic diagram of the internal structure of the concentrated water barrier in the embodiment of the present application.

[0035] Figure 5 It is a schematic diagram of the structure of a multi-stage reverse osmosis system in an embodiment of the present application.

[0036] Figure 6 It is a schematic diagram of the structure of the equipment used in the high-concentration process in the embodiment of the present application.

[0037] Figure 7 This is a flow chart of a low-energy consumption, high-multiple concentration process in an embodiment of the present application.

[0038] In the figure: 1. water production pipe body; 2. water inlet pipe; 3. discharge pipe; 4. center pipe; 41. connecting hole; 42. first water production section; 43. second water production section; 5. reverse osmosis membrane element; 51. fresh water barrier; 52. concentrated water barrier; 521. filter membrane; 522. concentrated water screen; 6. plugging part; 7. low-pressure pump; 8. water production net; 9. guide part; 91. guide plate; 10. multi-stage reverse osmosis system; 101. nanofiltration system. DETAILED DESCRIPTION

[0039] The following is combined with Figure 1-Figure 7 This application is described in further detail.

[0040] The embodiments of the present application disclose a reverse osmosis water production pipe, a multi-stage reverse osmosis system and a low-energy consumption high-multiple concentration process.

[0041] Reference Figure 1 , Figure 2 and Figure 3 A reverse osmosis water pipe includes a water production pipe body 1, a central pipe 4, a reverse osmosis membrane element 5, a plugging piece 6 and a water production network 8.

[0042] One end of the water production pipe body 1 is connected to the water inlet pipe 2, and the other end of the water production pipe body 1 is connected to the discharge pipe 3. The central pipe 4 is inserted into the water production pipe body 1. A connecting hole 41 connecting the inner and outer sides of the central pipe 4 is opened on the pipe wall of the central pipe 4. The water production network 8 covers the outer wall of the central pipe 4 and covers the connecting hole 41. The reverse osmosis membrane element 5 is wrapped around the central pipe 4 and is located outside the water production network 8. The plugging member 6 is arranged in the central pipe 4, and the peripheral wall of the plugging member 6 is fixedly connected to the inner wall of the central pipe 4.

[0043] When industrial wastewater is treated, the industrial wastewater is input through the water inlet pipe 2, and the industrial wastewater is reverse osmotic through the reverse osmosis membrane element 5 inside the water production pipe body 1 to produce initial produced water and initial concentrated water. The initial concentrated water will be discharged through the discharge pipe 3, and the initial produced water passes through the water production network 8 and enters the first water production section 42 of the central pipe 4 via the connecting hole 41. At this time, the low-pressure pump 7 inputs high-concentration produced water to the second water production section 43, and the high-concentration produced water enters the water production network 8 through the connecting hole 41, and enters the first water production section 42 from the water production network 8 through the connecting hole 41 to mix with the initial produced water, thereby increasing the concentration of the produced water in the first water production section 42, reducing the osmotic pressure difference, facilitating the produced water to pass through the reverse osmosis membrane element 5, accelerating the reverse osmosis efficiency, and reducing the reverse osmosis cost.

[0044] Reference Figure 2 and Figure 4 A flow guide 9 is arranged inside the reverse osmosis membrane element 5 . The flow guide 9 is composed of a plurality of flow guide plates 91 arranged in parallel. The flow guide plates 91 are arranged in a rotational manner around the central tube 4 .

[0045] A flow guide 9 is arranged inside the reverse osmosis membrane element 5. The flow guide 9 guides the water flow entering the reverse osmosis membrane element 5 through parallel guide plates 91, so that the water flow rotates and flows around the direction of the central tube 4, thereby generating centripetal force when the water flow flows. Impurities in the water flow are gathered in the direction away from the central tube 4 due to the centripetal force, thereby reducing the osmotic pressure difference on both sides of the reverse osmosis membrane element 5 close to the central tube 4, facilitating the output of produced water into the central tube 4, thereby accelerating the reverse osmosis efficiency.

[0046] Reference Figure 2 and Figure 4 The reverse osmosis membrane element 5 is composed of a fresh water barrier 51 and a concentrated water barrier 52. The fresh water barrier 51 and the concentrated water barrier 52 are alternately wound around the central tube 4 and are located outside the water production network 8. A reverse osmosis layer of the water production network 8 - fresh water barrier 51 - concentrated water barrier 52 - fresh water barrier 51 is formed outside the central tube 4.

[0047] By forming a reverse osmosis layer, the water flow is separated for reverse osmosis, which increases the reverse osmosis area and facilitates the separation of produced water from industrial wastewater.

[0048] The concentrated water barrier 52 comprises a concentrated water separation net 522, and filter membranes 521 are arranged on both sides of the concentrated water separation net 522. The filter membranes 521 on both sides of the concentrated water separation net 522 are formed by folding the same filter membrane 521. The fresh water barrier 51 is arranged as a fresh water separation net.

[0049] The stability of the concentrated water barrier 52 is increased, and the filter membranes 521 are separated by the concentrated water separation net 522, which reduces the probability of adhesion between the filter membranes 521, so that the filter membranes 521 are evenly distributed with water, thereby improving the filtering efficiency of the concentrated water barrier 52.

[0050] The implementation principle of a reverse osmosis water production pipe in an embodiment of the present application is as follows: when treating industrial wastewater, the water inlet pipe 2 inputs industrial wastewater, so that the industrial wastewater contacts the reverse osmosis membrane element 5 and performs reverse osmosis, thereby forming initial produced water and initial concentrated water. The initial concentrated water is discharged from the discharge pipe 3, and the initial produced water passes through the water production network 8 and enters the first water production section 42 of the central tube 4 from the connecting hole 41. At the same time, the low-pressure pump 7 inputs high-concentration produced water (the high-concentration produced water is nanofiltration produced water) to the second water production section 43. The high-concentration produced water passes through the connecting hole 41 and the water production network 8 and crosses the sealing member 6 to enter the first water production section 42 and mix with the initial produced water, thereby reducing the osmotic pressure difference on both sides of the reverse osmosis membrane element 5, facilitating the initial produced water to pass through the reverse osmosis membrane element 5 and enter the central tube 4, thereby accelerating the reverse osmosis efficiency and reducing the reverse osmosis cost.

[0051] A multi-stage reverse osmosis system, referring to Figure 2 , Figure 3 and Figure 5 A multi-stage reverse osmosis system 10 is formed by connecting a plurality of reverse osmosis water production pipes in sequence, and the number of the reverse osmosis water production pipes is preferably 2, 3, or 4. The discharge pipe 3 of the previous reverse osmosis water production pipe is connected to the water inlet pipe 2 of the next reverse osmosis water production pipe.

[0052] The multi-stage reverse osmosis system 10 can perform multi-stage reverse osmosis on industrial wastewater, thereby reducing the loss of water resources during the reverse osmosis treatment process.

[0053] A low energy consumption high concentration process, refer to Figure 6 and Figure 7 , including the following steps: S1, pre-treating wastewater to obtain a pre-treated liquid; In the process of pre-treating the wastewater, the wastewater is subjected to organic matter removal treatment and denitrification treatment, and the wastewater after the organic matter removal treatment and denitrification treatment is subjected to oxidation treatment; Organic matter removal can be done by adding flocculants; S2, sending the pre-treated liquid to the multi-stage reverse osmosis system 10 for preliminary reverse osmosis treatment to obtain initial concentrated water and initial produced water discharged from the central tube; When performing the preliminary reverse osmosis treatment, the flow guide 9 in the multi-stage reverse osmosis system 10 can guide the flow of water and promote the separation of the initial produced water and the initial concentrated water, and the initial concentrated water is discharged through the discharge pipe 3; S3, sending the initial concentrated water into the nanofiltration system 101 to obtain nanofiltration product water and nanofiltration concentrated water; After the initial concentrated water enters the nanofiltration system 101, the organic matter is separated again, and the monovalent salt and the divalent salt are separated to form nanofiltration concentrated water and nanofiltration produced water with a concentration higher than that of the initial produced water; S4, mixing the nanofiltration produced water and the initial produced water from the central tube 4 to obtain intermediate produced water; S41, the nanofiltration produced water is sent to the second water production section 43 of the last stage reverse osmosis water production pipe of the multi-stage reverse osmosis system 10 through the low-pressure pump 7; S42, the nanofiltration produced water passes through the water production net 8 outside the central tube 4, bypasses the plugging member 6 and moves step by step to the first water production section 42 where the initial produced water is located, and mixes with the initial produced water to form intermediate produced water; The nanofiltration produced water and the initial produced water are mixed to obtain the intermediate produced water with higher concentration, thereby reducing the osmotic pressure difference on both sides of the reverse osmosis membrane element 5, accelerating the reverse osmosis efficiency, and reducing the energy consumption in the reverse osmosis process; S5, the intermediate produced water is subjected to reverse osmosis treatment through the reverse osmosis produced water pipe outside the multi-stage reverse osmosis system 10 to obtain final produced water; S51, the intermediate product water is used as the inlet water of the reverse osmosis water production pipe outside the multi-stage reverse osmosis system 10 to undergo reverse osmosis treatment to obtain final product water and osmotic concentrated water; S52, sending the osmotic concentrate mixed with the pre-treated liquid into the first-stage water inlet pipe 2 of the multi-stage reverse osmosis system 10 for reverse osmosis treatment.

[0054] The osmotic pressure difference between the intermediate water and the final water is much smaller than the osmotic pressure difference between the industrial wastewater and the final water. Compared with the conventional technical means of directly obtaining the final water from industrial wastewater, the energy consumption required in the reverse osmosis process is reduced, and at the same time, the impurities in the industrial wastewater are highly concentrated.

[0055] In a specific embodiment, wastewater (sodium chloride salt content 70g / L) is pretreated and pressurized to 66bar (6.6MPa) by a low-pressure pump 7 and pumped into the water inlet pipe 2 of the multi-stage reverse osmosis system 10. After concentration, wastewater (sodium chloride salt content 120g / L) is obtained. The wastewater is discharged from the discharge pipe 3 and enters the nanofiltration system 101. After entering the nanofiltration system 101, the organic matter is separated again, and the divalent salt and the monovalent salt are separated at the same time, to produce nanofiltration water (sodium chloride salt content 115g / L) and nanofiltration concentrated water (sodium chloride salt content 130g / L); the nanofiltration concentrated water is used as the final The concentrated water is discharged, and the nanofiltration water is used as the inlet water of the multi-stage reverse osmosis system 10; the nanofiltration water (sodium chloride salt content 115g / L) passes through the multi-stage reverse osmosis system 10 in sequence, and the concentration decreases from high to low, and finally forms intermediate water (sodium chloride salt content is 33g / L) and is discharged from the first water production section 42. The discharged intermediate water is then reverse osmosis filtered through the reverse osmosis water production pipe outside the multi-stage reverse osmosis system 10 to obtain osmotic concentrated water (sodium chloride salt content 70g / L) and final produced water (sodium chloride salt content 1g / L), and the osmotic concentrated water is then returned to the inlet pipe 2 of the multi-stage reverse osmosis system 10 for repeated reverse osmosis.

[0056] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. A reverse osmosis water production pipe, characterized in that: include: A water production pipe body (1) having one end connected to a water inlet pipe (2) and the other end connected to a discharge pipe (3); A central tube (4) is inserted into the water production tube body (1), a tube wall of the central tube (4) is provided with a connecting hole (41) connecting the inner and outer sides of the central tube (4), and the central tube (4) is used to provide a channel for the water production to flow out; A reverse osmosis membrane element (5) is wound around the central tube (4) and is used to reversely separate the introduced wastewater into produced water and concentrated water; a plugging member (6) disposed inside the central tube (4) and used to separate the central tube (4) into a plurality of first water production sections (42) and second water production sections (43) which are not connected to each other, wherein the first water production sections (42) are used to discharge produced water, and the second water production sections (43) are connected to a low-pressure pump (7), and the low-pressure pump (7) is used to transport high-concentration produced water; A water production network (8) is closely attached to the outer wall of the central tube (4) and covers the connecting hole (41); the water production network (8) connects the first water production section (42) and the second water production section (43) blocked by the blocking member (6).

2. A reverse osmosis water production pipe according to claim 1, characterized in that: It also comprises a flow guide (9), the flow guide (9) being rotatably arranged in the reverse osmosis membrane element (5), the flow guide (9) being used to guide the water flow in the reverse osmosis membrane element (5) to flow around the central tube (4) in a rotatable manner.

3. A reverse osmosis water production pipe according to claim 2, characterized in that: The flow guide member (9) is composed of a plurality of flow guide plates (91) arranged in a rotational manner, and different flow guide plates (91) are arranged in parallel.

4. The reverse osmosis water production pipe according to claim 1, characterized in that: The reverse osmosis membrane element (5) comprises a fresh water barrier (51) and a concentrated water barrier (52), wherein the fresh water barrier (51) and the concentrated water barrier (52) are alternately wound around the central tube (4).

5. A reverse osmosis water production pipe according to claim 4, characterized in that: The concentrated water blocker (52) comprises a filter membrane (521) and a concentrated water separation net (522); the filter membrane (521) is folded in half and arranged to clamp the concentrated water separation net (522).

6. A multi-stage reverse osmosis system, characterized in that: It is composed of a plurality of reverse osmosis water production pipes as described in any one of claims 1 to 5 connected in sequence, wherein the discharge pipe (3) of the previous reverse osmosis water production pipe is connected to the water inlet pipe (2) of the next reverse osmosis water production pipe.

7. A low energy consumption high multiple concentration process, characterized in that: The following steps are involved: S1, pre-treating wastewater to obtain a pre-treated liquid; S2, sending the pre-treated liquid into a multi-stage reverse osmosis system (10) for preliminary reverse osmosis treatment to obtain initial concentrated water and initial produced water discharged from the central tube (4); S3, sending the initial concentrated water into the nanofiltration system (101) to obtain nanofiltration product water and nanofiltration concentrated water; S4, mixing the nanofiltration produced water and the initial produced water from the central tube (4) to obtain intermediate produced water; S5, the intermediate water is subjected to reverse osmosis treatment through a reverse osmosis water production pipe outside the multi-stage reverse osmosis system (10) to obtain final water production.

8. A low energy consumption high concentration process according to claim 7, characterized in that: Step S4 includes: S41, the nanofiltration produced water is sent to the second water production section (43) of the last stage reverse osmosis water production pipe of the multi-stage reverse osmosis system (10) through a low-pressure pump (7); S42, the nanofiltration produced water passes through the water production net (8) outside the central tube (4), bypasses the plugging member (6), moves step by step to the first water production section (42) where the initial produced water is located, and mixes with the initial produced water to form intermediate produced water.

9. A low energy consumption high concentration process according to claim 7, characterized in that: Step S5 includes: S51, the intermediate product water is used as the inlet water of the reverse osmosis water production pipe outside the multi-stage reverse osmosis system (10) for reverse osmosis treatment to obtain final product water and osmotic concentrate; S52, sending the osmotic concentrate mixed with the pre-treated liquid into the first-stage water inlet pipe (2) of the multi-stage reverse osmosis system (10) for reverse osmosis treatment.

10. A low energy consumption high concentration process according to claim 7, characterized in that: Step S1 includes: performing organic matter removal treatment and denitrification treatment on the wastewater, and performing oxidation treatment on the treated wastewater again.

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