Reverse osmosis treatment system and method thereof

Abstract

The invention relates to the technical field of mine water concentration treatment, and provides a reverse osmosis treatment system and a method thereof.The reverse osmosis treatment system comprises a control system, a raw water booster pump, a precision filter, a plunger pump, a circulating pump, a plurality of STRO membrane sets arranged in parallel, an internal circulation pressure reducing valve, an energy recovery device and a concentrated liquor outward-discharging pneumatic valve; the raw water booster pump, the precision filter, the plunger pump, the circulating pump and the STRO membrane group are connected in sequence; effluent of each STRO membrane group is divided into a concentrated solution and a permeate, the permeate is discharged through a water production pneumatic valve, one part of the concentrated solution returns to an inlet of the circulating pump, and the other part of the concentrated solution is discharged after passing through the energy recovery device. The yield of the concentrated liquor is reduced by half compared with that of secondary concentrated liquor, a large number of available water resources are saved, meanwhile, the treatment scale of rear-end evaporation crystallization equipment is reduced, the tolerance of a film element is protected, the service life of the film element is prolonged, and energy consumption is greatly reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of mine water concentration treatment, and in particular to a reverse osmosis treatment system and a method thereof. Background Art

[0002] At present, the resource utilization of mine wastewater is the best choice to solve the water shortage in coal mines and the pollution of the environment by mine wastewater, which can achieve the unity of social benefits, environmental benefits and economic benefits. With the development of science and the improvement of people's awareness of environmental protection, the resource utilization of mine water has been widely valued by coal mining enterprises. In order to effectively purify mine wastewater, it is generally necessary to select a suitable mine wastewater purification process according to the type of mine wastewater and the composition of pollutants, and deep treatment membrane concentration is an indispensable part. Membrane concentration usually adopts the "step-by-step collaborative pretreatment + multi-stage coupled membrane concentration" process. Among them, three-stage membrane concentration is less used because the process is not mature enough. The three-stage membrane concentration system can reduce the output of concentrated liquid by multiples, which has very important theoretical significance and practical value for improving the level of scientific management, reducing production costs, and achieving benign operation.

[0003] As an important unit for the resource utilization of mine wastewater, the three-stage membrane concentration system has advanced technology, high desalination rate, and greatly reduced concentrated liquid production. It can become the ultimate membrane concentration treatment method for mine wastewater resource utilization, but it also has the characteristics of high system design difficulty, high operating costs, and complex maintenance. The inlet TDS of the three-stage membrane concentration is about 60,000 mg / L, and the final concentrated brine TDS can reach more than 110,000 mg / L, with a maximum osmotic pressure of up to 12 MPa. It can be seen that the water quality environment of the three-stage concentrated reverse osmosis operation is extremely poor and the energy consumption is extremely high.

[0004] At present, the three-stage membrane concentration system generally adopts an ultra-high pressure reverse osmosis system with an energy recovery device, mainly a scroll RO system and a DTRO system. The scroll RO system is generally more used in the secondary concentration stage. The system uses a turbine energy recovery device. The raw liquid has good water quality and low pressure. When used in the tertiary concentration stage, its process design and performance are difficult to meet production requirements in terms of operating pressure and desalination rate. The ultra-high pressure DTRO system can meet the requirements in terms of operating pressure and desalination rate, but DTRO has the disadvantages of complex structure, high failure rate, high operation and maintenance cost, easy fouling and difficult chemical cleaning.

[0005] The mesh-tube reverse osmosis STRO membrane was originally designed for treating landfill leachate. As an updated product of DTRO, it has other decisive advantages in addition to the advantages of DTRO membrane: the open flow channel has stronger anti-fouling and clogging ability; the filtration area of ​​a single membrane is about three times that of a DTRO membrane element, and the number of membrane elements is reduced by two-thirds under the same processing conditions; the membrane element has low pressure loss and lower energy consumption; maintenance and repair are more convenient and simple. At present, in the field of mine water resource utilization, there is no design plan and use case of 12MPa STRO membrane system in China.

[0006] At present, a common type of high-pressure reverse osmosis energy-saving system is basically based on spiral RO, and the system is designed into a multi-stage (stage) type, generally more than two stages, each stage passes through the membrane once, and no inter-stage circulation is added; the latter stage treats the concentrated liquid of the previous stage, and the booster pump provides osmotic pressure between stages; the energy recovery device absorbs the pressure energy of the concentrated liquid at the end of the reverse osmosis system and raises the quantitative raw liquid to the osmotic pressure. In this way, through the energy exchange method, part of the water flow is shared and energy consumption is reduced. For example, patent documents CN116685391A, CN218784737U, and CN209519609U all disclose related processes, but the above high-pressure reverse osmosis energy-saving systems have the following shortcomings:

[0007] 1. This system is more used in the secondary concentration stage. Due to the limitations of process design, its operating pressure level is 75 bar. If the inlet TDS is around 60,000 mg / L and the concentrate TDS is 110,000 mg / L, its operating pressure cannot reach 120 bar. It cannot be used in the tertiary concentration stage and it is difficult to meet production requirements.

[0008] 2. Each section passes through the membrane once, without inter-section circulation. It is suitable for treating mine wastewater with good water quality. This process is not suitable for treating mine wastewater with poor water quality (high TDS). If this process is used, the membrane filtration flux will far exceed the limit and the system will not be able to operate. Moreover, in this process, the membrane in the latter section treats the concentrated liquid in the former section, which causes the membrane elements in the latter section to be frequently blocked and have a reduced lifespan, making the system operation extremely unstable.

[0009] The second common type is a high-pressure reverse osmosis energy-saving system using a turbine energy recovery device. The system is designed as a single-stage or double-stage system, and each stage passes through the membrane once without inter-stage circulation. The turbine energy recovery device is connected in series in the process route, playing the role of a high-pressure pump or an inter-stage booster pump, absorbing the pressure energy of the concentrated liquid at the end of the reverse osmosis system and raising the original liquid to the designed osmotic pressure. In this way, through energy exchange, part of the water inlet pressure is shared and energy consumption is reduced. For example, patent documents CN101913716A, CN106045098A, and CN111268764A all disclose related processes, but the disadvantage of the above design is that the energy recovery efficiency is low, and the energy utilization rate is only between 60% and 70%, or even lower, resulting in energy waste.

[0010] The third common type of ultra-high pressure reverse osmosis system is the DTRO / STRO system. At present, this system is mainly used in the field of landfill leachate treatment, and rarely involved in the field of zero-emission resource utilization of coal mine wastewater. Although the operating pressure of the system can reach 120Bar, the process treatment methods of the two are completely different, and the process treatment methods need to be redesigned according to the mine wastewater. For example, patent documents CN113173661B and CN110294551A both disclose related processes, but the above design is blank in the application field of three-stage concentration of zero-emission mine wastewater, and there is no process treatment method. The existing system design has no energy recovery and reuse, and has the disadvantages of high energy consumption and low degree of automation. Summary of the invention

[0011] In view of the defects in the prior art, an object of the present invention is to provide a reverse osmosis treatment system and method thereof.

[0012] A reverse osmosis treatment system provided by the present invention includes a control system, a raw water booster pump, a precision filter, a plunger pump, a circulation pump, a plurality of STRO membrane groups arranged in parallel, an internal circulation pressure reducing valve, an energy recovery device, and a concentrated liquid exhaust actuating valve;

[0013] The raw water booster pump, precision filter, plunger pump, circulation pump, and STRO membrane group are connected in sequence;

[0014] The water output from each group of the STRO membrane group is divided into a concentrate and a permeate, and the permeate is discharged through the fourth pipeline and the fifth pipeline in turn through the water production pneumatic valve, a part of the concentrate from the STRO membrane group returns to the inlet of the circulation pump through the internal circulation pressure reducing valve, and the other part of the concentrate passes through the energy recovery device and is discharged through the low-pressure concentrate discharge pipeline and the concentrate discharge pneumatic valve;

[0015] The control system is respectively connected to the raw water booster pump, the plunger pump, the circulation pump, the water production pneumatic valve, the internal circulation pressure reducing valve, and the concentrated liquid exhaust pneumatic valve;

[0016] Instrument components are provided at the outlet of the raw water booster pump, the permeate pipeline of the STRO membrane group, and the concentrated liquid pipeline. The control system can select the actual control speed of each pump and / or the opening of each valve according to the detection parameters received from the instrument components.

[0017] Preferably, the concentrated liquid coming out of the STRO membrane group first enters the concentrated liquid membrane outlet pipeline, the concentrated liquid membrane outlet pipeline is connected to the internal circulation pressure reducing valve via the internal circulation pipeline, the concentrated liquid membrane outlet pipeline is connected to the first inlet of the energy recovery device via the high-pressure concentrated liquid inlet pipeline, the first outlet of the energy recovery device is connected to the low-pressure concentrated liquid discharge pipeline, and the concentrated liquid membrane outlet pipeline is also connected to the low-pressure concentrated liquid discharge pipeline through a pressure regulating valve.

[0018] Preferably, it further comprises a chemical cleaning pipeline, the plunger pump and the circulation pump are connected via a third pipeline, and the chemical cleaning pipeline is connected to the third pipeline via a cleaning high-pressure pneumatic valve;

[0019] A small amount of cleaning liquid coming out of the STRO membrane group enters the cleaning tank through the fifth pipeline and the water production end cleaning liquid return pneumatic valve;

[0020] Most of the cleaning liquid coming out of the STRO membrane module enters the cleaning tank through the concentrated liquid membrane outlet pipeline, the pressure regulating valve, and the concentrated liquid end cleaning liquid reflux pneumatic valve;

[0021] The control system is respectively connected to the cleaning high-pressure pneumatic valve, the water production end cleaning liquid reflux pneumatic valve, and the concentrated liquid end cleaning liquid reflux pneumatic valve.

[0022] Preferably, it further comprises a flushing pneumatic valve, the flushing pneumatic valve is installed on the sixth pipeline, the raw water booster pump is connected to the precision filter through the first pipeline, and the sixth pipeline is connected to the first pipeline;

[0023] The flushing water enters from the sixth pipeline to flush the STRO membrane group, and a small portion of the flushing water after flushing enters the wastewater tank through the fourth pipeline, the fifth pipeline, and the wastewater exhaust pneumatic valve at the water production end;

[0024] Most of the flushing water after flushing is discharged into the wastewater pool through the concentrate outlet pipeline, high-pressure concentrate inlet pipeline, pressure regulating valve, and concentrate end wastewater exhaust pneumatic valve;

[0025] The control system is respectively connected to the flushing pneumatic valve, the waste water exhaust pneumatic valve at the water production end, and the waste water exhaust pneumatic valve at the concentrated liquid end.

[0026] Preferably, the precision filter is connected to the plunger pump through a second pipeline, and part of the low-pressure raw liquid in the second pipeline enters the second inlet of the energy recovery device through the low-pressure raw liquid inlet pipeline, is pressurized, comes out from the second outlet of the energy recovery device, and enters the inlet of the circulation pump after passing through the high-pressure raw liquid outlet pipeline.

[0027] Preferably, the raw water booster pump is connected to the precision filter via a first pipeline, the dosing device is connected to the first pipeline via a dosing pipeline, a water inlet pump rear instrument assembly is also provided on the first pipeline, a water production instrument assembly is provided on the fifth pipeline, and the water inlet pump rear instrument assembly includes at least one of the following detection components:

[0028] Flow meter;

[0029] Conductivity meter;

[0030] Pressure transmitter;

[0031] Pressure gauge;

[0032] Temperature sensor;

[0033] The water production meter assembly includes at least one of the following detection components:

[0034] Flow meter;

[0035] Pressure transmitter;

[0036] Pressure gauge;

[0037] Temperature sensor.

[0038] According to a chemical cleaning method of a reverse osmosis treatment system provided by the present invention, the reverse osmosis treatment system is used, and the steps are as follows:

[0039] Step 1: Open the cleaning high-pressure pneumatic valve, the internal circulation pressure reducing valve, the water production end cleaning liquid reflux pneumatic valve, the pressure regulating valve, and the concentrated liquid end cleaning liquid reflux pneumatic valve;

[0040] Step 2: The chemical cleaning liquid enters the STRO membrane group through the chemical cleaning pipeline and the circulation pump. The cleaning liquid coming out of the STRO membrane group first returns to the inlet of the circulation pump through the internal circulation pipeline and then enters the STRO membrane group again to realize internal circulation cleaning;

[0041] Step 3: After the cleaning reaches the set time, a small amount of cleaning liquid coming out of the STRO membrane group returns to the cleaning tank through the cleaning liquid reflux pneumatic valve, and most of the cleaning liquid coming out of the STRO membrane group returns to the cleaning tank through the concentrated liquid membrane outlet pipeline, the pressure regulating valve, and the concentrated liquid end cleaning liquid reflux pneumatic valve.

[0042] According to a shutdown flushing method of a reverse osmosis treatment system provided by the present invention, the reverse osmosis treatment system is used, and the method comprises the following steps:

[0043] S1: Open the flushing pneumatic valve, the internal circulation pressure reducing valve, the wastewater exhaust pneumatic valve at the water production end, the pressure regulating valve, and the wastewater exhaust pneumatic valve at the concentrate end;

[0044] S2: The flushing water enters the STRO membrane group through the flushing pneumatic valve, precision filter, plunger pump, and circulation pump for flushing. The flushing liquid from the STRO membrane group first returns to the inlet of the circulation pump through the internal circulation pipeline and then enters the STRO membrane group again to realize internal circulation flushing;

[0045] S3: After the cleaning reaches the set time, a small amount of flushing water from the STRO membrane group is discharged into the wastewater pool through the wastewater exhaust pneumatic valve at the water production end; most of the flushing water from the STRO membrane group is discharged into the wastewater pool through the concentrate outlet pipeline, the pressure regulating valve, and the concentrate end wastewater exhaust pneumatic valve.

[0046] According to an energy recovery method of a reverse osmosis treatment system provided by the present invention, the energy recovery method adopts the reverse osmosis treatment system as follows:

[0047] Part of the concentrated liquid that passes through the concentrated liquid outlet pipeline enters the energy recovery device through the high-pressure concentrated liquid inlet pipeline for energy conversion. The high-pressure concentrated liquid can drive the turbine at one end of the energy recovery device to rotate, so that the high-pressure water energy is converted into mechanical energy. The rotating mechanical energy can drive the turbine at the other end of the energy recovery device to rotate and absorb the raw liquid. The raw liquid enters the second inlet of the energy recovery device through the low-pressure raw liquid inlet pipeline and is pressurized, and then comes out from the second outlet of the energy recovery device to complete the energy conversion.

[0048] According to a method for filtering raw liquid of a reverse osmosis treatment system provided by the present invention, the reverse osmosis treatment system is used, and the method comprises the following steps:

[0049] M1: Open the water production pneumatic valve, internal circulation pressure reducing valve, pressure regulating valve, and concentrated liquid exhaust pneumatic valve;

[0050] M2: Start the raw water booster pump to deliver the raw water to the STRO membrane group through the precision filter and the plunger pump via the circulation pump, wherein the amount of water required by the STRO membrane group includes a portion of the concentrated liquid at the outlet of the STRO membrane group that flows back to the inlet of the circulation pump;

[0051] M3: The STRO membrane group separates the raw water under high pressure, and the water output from the STRO membrane group is divided into two parts: concentrated liquid and permeate. The permeate produced by each group of the STRO membrane groups is collected and discharged through the fifth pipeline and the water production pneumatic valve; the concentrated liquid of each group of the STRO membrane groups is collected and discharged through the concentrated liquid membrane outlet pipeline, and one part of the discharged concentrated liquid enters the internal circulation process and returns to the STRO membrane group to participate in production, and the other part enters the energy recovery device to participate in energy conversion and then is discharged.

[0052] Compared with the prior art, the present invention has the following beneficial effects:

[0053] 1. The present invention is suitable for higher TDS filtration and higher operating pressure. The secondary concentrate is further concentrated, and the TDS concentration after concentration reaches more than 110,000 mg / L. The concentrate output is directly reduced by half compared with the secondary concentrate, saving a large amount of available water resources while reducing the processing scale of the back-end evaporation and crystallization equipment. At the same time, the present invention can stably and persistently operate under an ultra-high pressure working environment, increase the internal circulation design to ensure that the filtration flux of the system is within the scientific design range, and protect the tolerance and life of the membrane element; increase the energy recovery design, the energy recovery efficiency is as high as more than 97%, which greatly reduces energy consumption, and improves the ability of automatic control through automatic control.

[0054] 2. The present invention adopts a mesh-tube reverse osmosis membrane, which occupies a small area and has a larger membrane area, thereby increasing the system's anti-pollution ability, reducing energy consumption, and making maintenance and repair more convenient and simple.

[0055] 3. The operating water quality environment of the present invention is extremely poor. The operating flux of the entire system must be controlled at about 10LMH. The single flux of the stock solution through the membrane will seriously exceed the standard and cause the system to collapse. By designing an internal circulation system, the circulation flow rate can be increased to reduce the membrane flux, ensuring stable and long-term operation of the system. At the same time, a single-stage process design is implemented to ensure that the water quality passing through the membrane is basically the same, protecting the tolerance and life of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] Other features, objects and advantages of the present invention will become more apparent from the detailed description of non-limiting embodiments made with reference to the following drawings:

[0057] Figure 1 It is a schematic diagram of the process flow of the present invention.

[0058] The figure shows:

[0059] Raw water booster pump 1;

[0060] Instrument assembly 2 after water inlet pump;

[0061] Precision filter 3;

[0062] Filter post-instrument assembly 4;

[0063] Piston pump 5;

[0064] Safety valve 6;

[0065] High pressure pump rear instrument assembly 7;

[0066] Circulation pump 8;

[0067] Circulation pump rear instrument assembly 9;

[0068] STRO membrane group 10;

[0069] Water production float flowmeter 11;

[0070] Water production meter assembly 12;

[0071] Production water sampling port 13;

[0072] Water production pneumatic valve 14;

[0073] Concentrate out of membrane pipeline 15;

[0074] Internal circulation pipeline 16;

[0075] Internal circulation pressure reducing valve 17;

[0076] High-pressure concentrate inlet pipeline 18;

[0077] Energy recovery device 19;

[0078] High-pressure raw liquid outlet pipeline 20;

[0079] Low-pressure raw liquid inlet pipeline 21;

[0080] Low-pressure concentrated liquid discharge pipeline 22;

[0081] Pressure regulating valve 23;

[0082] Concentrate meter assembly 24;

[0083] Concentrate exhaust actuating valve 25;

[0084] Chemical cleaning pipeline 26;

[0085] Water production end cleaning liquid return pneumatic valve 27; concentrated liquid end cleaning liquid return pneumatic valve 28; flushing pneumatic valve 29;

[0086] A hydraulic valve 30 for exhausting wastewater from the water production end; a hydraulic valve 31 for exhausting wastewater from the concentrated liquid end; and a dosing pipeline 32;

[0087] Cleaning the high pressure pneumatic valve 33;

[0088] Concentrate film outlet instrument component 34;

[0089] Antiscalant dosing point 35;

[0090] A first pipeline 101;

[0091] A second pipeline 102;

[0092] The third pipeline 103;

[0093] Fourth pipeline 104;

[0094] Fifth pipeline 105;

[0095] Sixth pipeline 106;

[0096] Symbols in the instrument components:

[0097] FI float flowmeter, FIT electromagnetic flowmeter, PI pressure gauge, PT pressure transmitter, TIT temperature sensor, NIT conductivity meter, PH meter. DETAILED DESCRIPTION

[0098] The present invention is described in detail below in conjunction with specific embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but are not intended to limit the present invention in any form. It should be noted that, for those of ordinary skill in the art, several changes and improvements can also be made without departing from the concept of the present invention. These all belong to the protection scope of the present invention.

[0099] The present invention is in the field of zero-discharge of mine water resources, especially in the three-stage membrane concentration treatment stage. The present invention is designed for the three-stage concentration process and provides a reverse osmosis treatment system, such as Figure 1 As shown, it includes a control system, a raw water booster pump 1, a precision filter 3, a plunger pump 5, a circulation pump 8, multiple groups of STRO membrane groups 10 arranged in parallel, an internal circulation pressure reducing valve 17, an energy recovery device 19 and a concentrated liquid exhaust actuating valve 25. The raw water booster pump 1, the precision filter 3, the plunger pump 5, the circulation pump 8 and the STRO membrane group 10 are connected in sequence to realize the raw liquid filtration process. Specifically, the raw water booster pump 1 is connected to the precision filter 3, and the precision filter 3 is connected to the plunger. Pump 5, the plunger pump 5 is connected to a circulation pump 8, the circulation pump 8 absorbs the pressurized water from the plunger pump 5, the energy recovery device 19 and the internal circulation pipeline 16 and pumps it to the STRO membrane group 10 for filtration. Multiple groups of STRO membrane groups 10 are used in parallel, and the water output of each group of STRO membrane groups 10 is divided into concentrated liquid and permeate. The permeate is discharged through the fourth pipeline 104 and the fifth pipeline 105 in turn through the water production pneumatic valve 14. The fifth pipeline 105 is provided with a water production sampling port 13, which can be used for sampling and detection.

[0100] Specifically, a part of the concentrated liquid coming out of the STRO membrane group 10 returns to the inlet of the circulation pump 8 through the internal circulation pressure reducing valve 17 to realize the internal circulation process. The internal circulation is designed to adapt to the water quality environment, achieve the concentration multiple, and meet the operating parameters of the system. The equipment involved in the internal circulation process includes the circulation pump 8, the instrument component 9 after the circulation pump, the STRO membrane group 10, the concentrated liquid membrane outlet pipeline 15, the internal circulation pipeline 16, and the internal circulation pressure reducing valve 17. The circulation pump 8 sends the circulating water to the STRO membrane group 10. After the circulation filtration, most of the concentrated liquid passes through the concentrated liquid membrane outlet pipeline 15, the internal circulation pipeline 16, and the internal circulation pressure reducing valve 17 to return to the circulation pump 8 to continue to participate in the production.

[0101] Furthermore, another part of the concentrated liquid is discharged through the low-pressure concentrated liquid discharge pipeline 22 and the concentrated liquid discharge pneumatic valve 25 after completing the energy recovery process through the energy recovery device 19. The pipelines or equipment involved in the energy recovery process include the high-pressure concentrated liquid inlet pipeline 18, the energy recovery device 19, the high-pressure raw liquid outlet pipeline 20, the low-pressure raw liquid inlet pipeline 21, and the low-pressure concentrated liquid discharge pipeline 22. A part of the concentrated liquid that passes through the concentrated liquid membrane outlet pipeline 15 enters the high-pressure concentrated liquid inlet pipeline 18, and the high-pressure concentrated liquid undergoes energy conversion after passing through the energy recovery device 19. The converted low-pressure concentrated liquid is discharged through the low-pressure concentrated liquid discharge pipeline 22 and the concentrated liquid discharge pneumatic valve 25; during the energy conversion process, the low-pressure raw liquid passes through the low-pressure raw liquid inlet pipeline 21, and after pressurization, enters the circulation pump 8 through the high-pressure raw liquid outlet pipeline 20.

[0102] It should be noted that the concentrated liquid coming out of the STRO membrane group 10 first enters the concentrated liquid membrane outlet pipeline 15, the concentrated liquid membrane outlet pipeline 15 is connected to the internal circulation pressure reducing valve 17 via the internal circulation pipeline 16, the concentrated liquid membrane outlet pipeline 15 is connected to the first inlet of the energy recovery device 19 via the high-pressure concentrate inlet pipeline 18, the first outlet of the energy recovery device 19 is connected to the low-pressure concentrate discharge pipeline 22, and the concentrated liquid membrane outlet pipeline 15 is also connected to the low-pressure concentrate discharge pipeline 22 through the pressure regulating valve 23.

[0103] The control system is respectively connected with the raw water booster pump 1, the plunger pump 5, the circulation pump 8, the water production pneumatic valve 14, the internal circulation pressure reducing valve 17, the concentrate exhaust pneumatic valve 25, the water production end cleaning liquid reflux pneumatic valve 27, the concentrate end cleaning liquid reflux pneumatic valve 28, the flushing pneumatic valve 29, the water production end waste water exhaust pneumatic valve 30, the concentrate end waste water exhaust pneumatic valve 31, and the cleaning high pressure pneumatic valve 33. The control system can control the start and stop of each pump and the switch of each valve to meet the needs of the system. Instrument components are arranged at the outlet of the raw water booster pump 1, the permeate pipeline of the STRO membrane group 10, and the concentrate pipeline. The control system can select the actual control speed of each pump and / or the opening of each valve according to the detection parameters of the instrument components received to meet the needs of each control pressure and flow rate and improve the efficiency of water treatment.

[0104] The present invention also includes a chemical cleaning pipeline 26, the plunger pump 5 and the circulation pump 8 are connected through the third pipeline 103, and the chemical cleaning pipeline 26 is connected to the third pipeline 103 through the cleaning high-pressure pneumatic valve 33; a small part of the cleaning liquid coming out of the STRO membrane group 10 passes through the fifth pipeline 105 and enters the cleaning tank through the water production end cleaning liquid return pneumatic valve 27; most of the cleaning liquid coming out of the STRO membrane group 10 enters the cleaning tank through the concentrate film outlet pipeline 15, the pressure regulating valve 23, and the concentrated liquid end cleaning liquid return pneumatic valve 28, and passes through the above The configuration can complete the chemical cleaning process. The chemical cleaning process and the raw liquid filtration process share some pipelines and equipment. The chemical cleaning pipeline 26 is equipped with a cleaning high-pressure pneumatic valve 33, which is then connected to the raw liquid filtration pipeline, through the circulation pump 8, the STRO membrane group 10, the internal circulation pipeline 16, and finally the water production end returns to the cleaning tank through the cleaning liquid reflux pneumatic valve 27, and the concentrate end returns to the cleaning tank through the concentrated liquid membrane outlet pipeline 15, the high-pressure concentrated liquid inlet pipeline 18, the energy recovery device 19, the low-pressure concentrated liquid discharge pipeline 22, and the concentrated liquid end cleaning liquid reflux pneumatic valve 28.

[0105] The present invention also includes a flushing pneumatic valve 29, which is used to complete the shutdown flushing process. The flushing process and the raw liquid filtration process share some pipelines and equipment. The flushing pneumatic valve 29 is installed on the sixth pipeline 106. The raw water booster pump 1 is connected to the precision filter 3 through the first pipeline 101, and the sixth pipeline 106 is connected to the first pipeline 101. After the flushing water enters from the sixth pipeline 106, the STRO membrane group 10 is flushed. A small part of the flushing water after flushing enters the wastewater pool through the fourth pipeline 104, the fifth pipeline 105, and the water production end wastewater exhaust pneumatic valve 30; most of the flushing water after flushing is discharged into the wastewater pool through the concentrate membrane outlet pipeline 15, the high-pressure concentrate inlet pipeline 18, the pressure regulating valve 23, and the concentrate end wastewater exhaust pneumatic valve 31;

[0106] Specifically, the precision filter 3 is connected to the plunger pump 5 through the second pipeline 102. Part of the low-pressure raw liquid in the second pipeline 102 enters the second inlet of the energy recovery device 19 through the low-pressure raw liquid inlet pipeline 21, is pressurized, and then comes out from the second outlet of the energy recovery device 19 and enters the inlet of the circulation pump 8 after passing through the high-pressure raw liquid outlet pipeline 20, thereby realizing energy recovery and utilization.

[0107] The raw water booster pump 1 is connected to the precision filter 3 through the first pipeline 101, and the dosing device is connected to the first pipeline 101 through the dosing pipeline 32. The first pipeline 101 is also provided with a water inlet pump rear instrument assembly 2, and the fifth pipeline 105 is provided with a water production instrument assembly 12. The water inlet pump rear instrument assembly 2 includes multiple detection components, such as a flow meter, a conductivity meter, a pressure transmitter, a pressure gauge, a temperature sensor, etc. The water production instrument assembly 12 includes multiple detection components, such as a flow meter, a pressure transmitter, a pressure gauge, a temperature sensor, etc.

[0108] The present invention also provides a chemical cleaning method for a reverse osmosis treatment system, which uses a reverse osmosis treatment system and includes the following steps:

[0109] Step 1: Open the cleaning high-pressure pneumatic valve 33, the internal circulation pressure reducing valve 17, the water production end cleaning liquid return pneumatic valve 27, the pressure regulating valve 23, and the concentrated liquid end cleaning liquid return pneumatic valve 28;

[0110] Step 2: The chemical cleaning liquid enters the STRO membrane group 10 through the chemical cleaning pipeline 26 and the circulation pump 8. The cleaning liquid from the STRO membrane group 10 first returns to the inlet of the circulation pump 8 through the internal circulation pipeline 16 and then enters the STRO membrane group 10 again to realize internal circulation cleaning;

[0111] Step 3: After the cleaning reaches the set time, a small amount of cleaning liquid coming out of the STRO membrane group 10 returns to the cleaning tank through the cleaning liquid reflux pneumatic valve 27, and most of the cleaning liquid coming out of the STRO membrane group 10 returns to the cleaning tank through the concentrated liquid membrane outlet pipeline 15, the pressure regulating valve 23, and the concentrated liquid end cleaning liquid reflux pneumatic valve 28.

[0112] The present invention also provides a shutdown flushing method for a reverse osmosis treatment system, which uses a reverse osmosis treatment system and includes the following steps:

[0113] S1: Open the flushing pneumatic valve 29, the internal circulation pressure reducing valve 17, the waste water exhaust pneumatic valve 30 at the water production end, the pressure regulating valve 23, and the waste water exhaust pneumatic valve 31 at the concentrate end;

[0114] S2: The flushing water passes through the flushing pneumatic valve 29, the precision filter 3, the plunger pump 5, and the circulation pump 8 to enter the STRO membrane group 10 for flushing. The flushing liquid from the STRO membrane group 10 first returns to the inlet of the circulation pump 8 through the internal circulation pipeline 16 and then enters the STRO membrane group 10 again to realize internal circulation flushing;

[0115] S3: After the cleaning reaches the set time, a small amount of flushing water from the STRO membrane group 10 is discharged into the wastewater pool through the wastewater exhaust pneumatic valve 30 at the water production end; most of the flushing water from the STRO membrane group 10 is discharged into the wastewater pool through the concentrate outlet pipeline 15, the pressure regulating valve 23, and the concentrate end wastewater exhaust pneumatic valve 31.

[0116] The present invention also provides an energy recovery method for a reverse osmosis treatment system, using a reverse osmosis treatment system, the energy recovery method is:

[0117] Part of the concentrated liquid passing through the concentrated liquid membrane outlet pipeline 15 enters the energy recovery device 19 through the high-pressure concentrated liquid inlet pipeline 18 for energy conversion. The high-pressure concentrated liquid can drive the turbine at one end of the energy recovery device 19 to rotate, so that the high-pressure water energy is converted into mechanical energy. The rotating mechanical energy can drive the turbine at the other end of the energy recovery device 19 to rotate and absorb the raw liquid. The raw liquid enters the second inlet of the energy recovery device 19 through the low-pressure raw liquid inlet pipeline 21 and is pressurized, and then comes out from the second outlet of the energy recovery device 19 to complete the energy conversion.

[0118] The present invention also provides a method for filtering raw liquid of a reverse osmosis treatment system, which adopts a reverse osmosis treatment system and comprises the following steps:

[0119] M1: Open the water production pneumatic valve 14, the internal circulation pressure reducing valve 17, the pressure regulating valve 23, and the concentrated liquid exhaust pneumatic valve 25;

[0120] M2: Start the raw water booster pump 1 to deliver the raw water to the STRO membrane group 10 through the precision filter 3, the plunger pump 5 and the circulation pump 8, wherein the amount of water required by the STRO membrane group 10 includes a portion of the concentrated liquid at the outlet of the STRO membrane group 10 that flows back to the inlet of the circulation pump 8;

[0121] M3: The STRO membrane group 10 separates the raw water under high pressure. The water output from the STRO membrane group 10 is divided into two parts: a concentrate and a permeate. The permeate produced by each group of STRO membrane groups 10 is collected and discharged through the fifth pipeline 105 and the water production pneumatic valve 14; the concentrate of each group of STRO membrane groups 10 is collected and discharged through the concentrate outlet pipeline 15. One part of the discharged concentrate enters the internal circulation process and returns to the STRO membrane group 10 to participate in production, and the other part enters the energy recovery device 19 to participate in energy conversion and then is discharged.

[0122] In addition to the above process flows and main components, the present invention also includes a number of instrument components, including an inlet pump rear instrument component 2, a filter rear instrument component 4, a high-pressure pump rear instrument component 7, a circulation pump rear instrument component 9, a water production float flowmeter 11, a water production instrument component 12, a concentrate instrument component 24, a concentrate membrane instrument component 34 and an antiscalant dosing point 35. The plunger pump 5 and the circulation pump 8 are preferably variable frequency pumps. In actual applications, the number of the plunger pump 5 and the STRO membrane group 10 can be increased or decreased according to design requirements.

[0123] like Figure 1 As shown, the process principle of the ultra-high pressure reverse osmosis treatment system in the present invention is as follows:

[0124] Raw liquid filtration process: When the reverse osmosis system starts to operate, the water production pneumatic valve 14, the internal circulation pressure reducing valve 17, the pressure regulating valve 23, and the concentrated liquid exhaust pneumatic valve 25 are opened, and other valves are closed. The raw water booster pump 1 delivers the raw water to the precision filter 3. The raw water booster pump 1 can provide the designed flow rate and a pressure of 3-5 bar. In addition to overcoming the pressure loss of the pipeline and the precision filter 3, this pressure also provides a certain pressure for the rear plunger pump 5; the precision filter 3 can remove fine solid particles in the raw water to avoid mechanical damage to the rear plunger pump 5 and the membrane assembly. A scale inhibitor dosing point 35 is also provided between the raw water booster pump 1 and the precision filter 3 to prevent scaling of the membrane assembly. A group of plunger pumps 5 are connected behind the precision filter 3. The plunger pumps 5 have three functions: one is to provide a stable water inlet flow rate for the system, and the other is to provide the required osmotic pressure for the system water production. Each plunger pump 5 is followed by a safety valve 6 with a set pressure value. For example, the set pressure of the safety valve is 110 bar. The safety valve 6 is used to timely relieve the pressure when the system pressure is too high to protect the system. The number of plunger pumps 5 is determined according to the system design parameters. The plunger pump 5 is controlled by a variable frequency motor. The frequency can be changed according to the actual operating conditions of the system to flexibly control the water inlet flow rate and operating pressure, thereby controlling the water production rate. The raw water after the plunger pump 5 enters the circulation pump 8. The main function of the circulation pump 8 is to directly send the high-pressure and high-flow raw water into the STRO membrane group 10. Since the flow rate provided by the plunger pump 5 does not meet the water volume required by the membrane group, a part of the concentrated liquid at the outlet of the membrane group is returned to the inlet of the circulation pump 8 through the circulation pump 8 to ensure that the membrane surface has sufficient flow and flow rate, achieve a reasonable design flux, and avoid membrane pollution. At the same time, the flow rate of the circulating pump 8 is controlled by the frequency converter to ensure that the system is in the best operating condition, avoiding damage to the membrane caused by excessive pressure and flow rate. The STRO membrane group 10 preferably uses 5 to 6 units in series, and multiple groups are connected in parallel in the process according to the size of the processing volume. The membrane element separates the raw water under high pressure, and the water output of the STRO membrane group 10 is divided into two parts: concentrate and permeate. The water produced by each group of membranes is collected and discharged through the fifth pipeline 105 and the water production pneumatic valve 14. The water production float flowmeter 11 can monitor the water production of each group of membranes, which is convenient for observing the water production and water color difference. The concentrated liquid of each group of membranes is collected and discharged through the concentrated liquid membrane pipeline 15. Part of the discharged concentrated liquid enters the internal circulation process to participate in production, and part enters the energy recovery process to participate in energy conversion.

[0125] Internal circulation process: The internal circulation process is added because the water quality is very poor. The concentration multiple can only be achieved by increasing the number of membrane elements and reducing the design flux. This requires a larger flow rate through the membrane to meet the design parameters. Therefore, most of the concentrated liquid discharged from the concentrated liquid outlet pipeline 15 is sucked into the STRO membrane group 10 through the internal circulation pipeline 16 and the internal circulation pressure reducing valve 17 to continue to participate in production. The main function of the internal circulation pressure reducing valve 17 is to automatically adjust the opening to control the pressure before and after the valve to ensure that the pressure before the internal circulation pressure reducing valve 17 is slightly higher than the pressure after the internal circulation pressure reducing valve 17, that is, the pressure in the high-pressure concentrated liquid inlet pipeline 18 is higher than the pressure in the high-pressure raw liquid outlet pipeline 20. This pressure is generally in the range of 0-0.6bar. This pressure difference is the key to ensure the normal operation of the energy recovery system. When the circulation pump 8 is also started, the pressure regulating valve 23 is gradually closed to hold the system pressure, so that the pressure rises and drives the energy recovery device to operate.

[0126] Energy recovery process: The energy recovery process includes a high-pressure concentrate inlet pipeline 18, an energy recovery device 19, a high-pressure raw liquid outlet pipeline 20, a low-pressure raw liquid inlet pipeline 21, and a low-pressure concentrate discharge pipeline 22. Another part of the concentrated liquid that passes through the concentrated liquid membrane outlet pipeline 15 enters the energy recovery device 19 through the high-pressure concentrate inlet pipeline 18 for energy conversion. The amount of this part of the concentrate is equal to the raw water inlet flow rate minus the designed water production flow rate. The high-pressure concentrated liquid drives the energy recovery device 19 to rotate, and the high-pressure water energy is converted into mechanical energy. The rotating mechanical energy drives the turbine at the other end to inhale the raw liquid. The raw liquid enters the energy recovery device 19 through the low-pressure raw liquid inlet pipeline 21 to continuously increase the pressure of the raw liquid until the designed water inlet pressure. This pressure value is basically equivalent to the pressure after the plunger pump 5, and the energy conversion is also completed. The converted high-pressure raw liquid is sucked into the STRO membrane group 10 by the circulation pump 8 again to participate in the production. It can be seen that there are three groups of circulating liquid entering the circulation pump 8 and the STRO membrane group 10, namely the water from the high-pressure plunger pump 5, the water after energy conversion, and a part of the concentrated liquid after filtration.

[0127] One of the innovative points of the ultra-high pressure reverse osmosis treatment system is energy saving, and the specific energy saving effect is also significant. The concentration multiple of the three-stage concentration process section of mine water is generally 2 times, that is, the water production rate is about 50%. Assuming that the system water intake (after the plunger pump 5) is 2 parts, the water production is 1 part, and the concentrated liquid is 1 part. Since the conversion efficiency of the energy recovery device is above 97%, plus the process loss, the basic conversion efficiency of 1 part of concentrated liquid is about 95%, which is equivalent to 0.95 parts of the 2 parts of the water intake is saved by energy conversion, and 1.05 parts are actually required for the work of the plunger pump 5. It can be seen that the energy-saving process saves 47.5% of energy consumption compared with the non-energy-saving design, and the annual energy saving is considerable.

[0128] The instrument assembly 2 after the water inlet pump is set on the pipeline between the raw water booster pump 1 and the precision filter 3. The flow sensor is used to monitor the water inlet flow, the conductivity meter is used to monitor the water inlet conductivity, the pressure sensor monitors the pressure after the water inlet pump, and the temperature sensor monitors the water inlet temperature in real time. The instrument assembly 4 after the filter is set between the precision filter 3 and the plunger pump 5: the pressure sensor can monitor the pressure before the plunger pump 5 to ensure that the pressure before the pump meets the operating requirements; at the same time, it monitors the pressure difference of the precision filter 3 together with the pressure sensor of the instrument assembly 2 after the water inlet pump. If the pressure difference is too high, it prompts to replace the filter element. The instrument assembly 7 after the high-pressure pump and the instrument assembly 9 after the circulating pump are respectively set after the plunger pump 5 and the circulating pump 8: they are used to monitor the pressure value at the rear end of the water pump. The difference between the two is the membrane pressure difference. According to the pressure difference, it is judged whether the membrane is blocked and whether chemical cleaning is required, which effectively protects the normal operation of the system. A concentrate film discharge instrument assembly 34 is provided in front of the energy recovery device 19. The concentrate film discharge instrument assembly 34 is used to monitor the concentrate film discharge pressure. The pressure difference between the concentrate film discharge instrument assembly 34 and the instrument assembly 7 after the high-pressure pump is controlled between 0-0.6 bar to ensure that the energy recovery process can operate stably. A water production instrument assembly 12 is provided at the water production end. The flow sensor in the water production instrument assembly 12 is used to monitor the water production flow rate, the conductivity meter is used to monitor the water production conductivity, and the pressure sensor monitors the water production pressure. A concentrate instrument assembly 24 is provided on the low-pressure concentrate discharge pipeline 22. The float flowmeter on the concentrate instrument assembly 24 is used to observe the concentrate flow rate, the conductivity meter is used to monitor the concentrate conductivity, the pressure sensor monitors the concentrate discharge pressure, and the temperature sensor monitors the concentrate temperature in real time. The temperature is used for temperature protection of chemical cleaning, and the pH is used for pH control during chemical cleaning.

[0129] Shutdown flushing process: When the system stops running, it is necessary to flush the inside of the system. Industrial water or system produced water can be used as flushing water. The flushing process shares some pipelines and equipment with the stock solution filtration process. During shutdown flushing, the flushing pneumatic valve 29, the internal circulation pressure reducing valve 17, the water production end waste water exhaust pneumatic valve 30, the pressure regulating valve 23, and the concentrated liquid end waste water exhaust pneumatic valve 31 are opened, and other valves are closed. The flushing water passes through the flushing pneumatic valve 29, the precision filter 3, the plunger pump 5, and the circulation pump 8 to enter the STRO membrane group 10 for flushing. Since the osmotic pressure is not increased, only a small amount of produced water is discharged through the water production end waste water exhaust pneumatic valve 30, and most of the flushing water is discharged through the concentrated liquid membrane outlet pipeline 15, the pressure regulating valve 23, and the concentrated liquid end waste water exhaust pneumatic valve 31.

[0130] Chemical cleaning process: The reverse osmosis system needs regular chemical cleaning. The purpose of cleaning is to remove organic matter and inorganic salts inside the system, protect the system for long-term stable operation, and reduce failures and damage. During chemical cleaning, the high-pressure pneumatic valve 33, the internal circulation pressure reducing valve 17, the water production end cleaning liquid reflux pneumatic valve 27, the pressure regulating valve 23, and the concentrated liquid end cleaning liquid reflux pneumatic valve 28 are opened, and other valves are closed. The chemical cleaning process and the raw liquid filtration process share some pipelines and equipment. The chemical cleaning liquid passes through the chemical cleaning pipeline 26, the circulation pump 8 enters the STRO membrane group 10, and then returns to the circulation pump 8 through the internal circulation pipeline 16 and enters the STRO membrane group 10 again, so that the membrane surface is continuously flushed for cleaning. A small part of the water production end returns to the cleaning tank through the cleaning liquid reflux pneumatic valve 27, and most of the cleaning liquid returns to the cleaning tank through the concentrated liquid membrane outlet pipeline 15, the pressure regulating valve 23, and the concentrated liquid end cleaning liquid reflux pneumatic valve 28.

[0131] The present invention is a new mine water treatment process, which is mainly used in the field of zero-discharge of mine water resources, especially in the three-stage membrane concentration treatment stage. The process can halve the concentrated liquid of the coal mine again, greatly reducing the subsequent concentrated liquid processing volume and processing scale, and the corresponding processing equipment and economic investment will also be reduced exponentially, such as evaporation crystallization equipment. The process system is designed for the three-stage concentration process, overcoming the higher TDS water quality and higher operating pressure, and further concentrating the secondary concentrated liquid. The TDS concentration after concentration reaches more than 110,000 mg / L. The concentrated liquid output is directly reduced by more than half compared with the secondary concentrated liquid, saving a large amount of available water resources, which plays an important role in the resource utilization and zero-discharge of mine wastewater.

[0132] The system of the present invention can be applied to the situation of extremely poor water quality environment. The operating flux of the whole system should be controlled at about 10LMH. The flux of the stock solution passing through the membrane system once will seriously exceed the standard and cause the system to collapse. The design of the internal circulation system can increase the circulation flow and reduce the membrane flux, ensuring the stable and long-term operation of the system. At the same time, the single-stage process design is implemented to ensure that the water quality passing through the membrane is basically the same, protecting the tolerance and life of the system. The present invention belongs to the ultra-high pressure treatment process, and its energy consumption is relatively high. If the high energy consumption is only used to exchange for half the concentrated liquid, the economy of the new process cannot be reflected. Therefore, the energy recovery design is added, and the energy recovery efficiency is as high as more than 97%, which greatly reduces the energy consumption; at the same time, the mesh-tube reverse osmosis membrane is adopted to increase the anti-pollution ability of the system, the membrane area is larger, the floor space is small, the energy consumption is lower than that of the DTRO membrane element, and the maintenance and repair are more convenient and simple.

[0133] In the description of the present application, it should be understood that the terms "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0134] The above describes the specific embodiments of the present invention. It should be understood that the present invention is not limited to the above specific embodiments, and those skilled in the art can make various changes or modifications within the scope of the claims, which does not affect the essence of the present invention. In the absence of conflict, the embodiments of the present application and the features in the embodiments can be combined with each other arbitrarily.

Claims

1. A reverse osmosis treatment system, characterized in that: It comprises a control system, a raw water booster pump (1), a precision filter (3), a plunger pump (5), a circulation pump (8), a plurality of STRO membrane groups (10) arranged in parallel, an internal circulation pressure reducing valve (17), an energy recovery device (19) and a concentrated liquid exhaust actuating valve (25); The raw water booster pump (1), precision filter (3), plunger pump (5), circulation pump (8), and STRO membrane group (10) are connected in sequence; The water output from each group of the STRO membrane group (10) is divided into a concentrate and a permeate, the permeate is discharged through the fourth pipeline (104) and the fifth pipeline (105) in sequence through the water production pneumatic valve (14), a part of the concentrate output from the STRO membrane group (10) is returned to the inlet of the circulation pump (8) through the internal circulation pressure reducing valve (17), and the other part of the concentrate is discharged through the energy recovery device (19) through the low-pressure concentrate discharge pipeline (22) and the concentrate discharge pneumatic valve (25); The control system is respectively connected to the raw water booster pump (1), the plunger pump (5), the circulation pump (8), the water production pneumatic valve (14), the internal circulation pressure reducing valve (17), and the concentrated liquid exhaust pneumatic valve (25); Instrument components are provided at the outlet of the raw water booster pump (1), the permeate pipeline of the STRO membrane group (10), and the concentrated liquid pipeline. The control system can select the actual control speed of each pump and / or the opening of each valve according to the detection parameters received from the instrument components.

2. The reverse osmosis treatment system according to claim 1, characterized in that: The concentrated liquid coming out of the STRO membrane group (10) first enters the concentrated liquid membrane outlet pipeline (15), the concentrated liquid membrane outlet pipeline (15) is connected to the internal circulation pressure reducing valve (17) via the internal circulation pipeline (16), the concentrated liquid membrane outlet pipeline (15) is connected to the first inlet of the energy recovery device (19) via the high-pressure concentrated liquid inlet pipeline (18), the first outlet of the energy recovery device (19) is connected to the low-pressure concentrated liquid discharge pipeline (22), and the concentrated liquid membrane outlet pipeline (15) is also connected to the low-pressure concentrated liquid discharge pipeline (22) via the pressure regulating valve (23).

3. The reverse osmosis treatment system according to claim 2, characterized in that: It also includes a chemical cleaning pipeline (26), the plunger pump (5) and the circulation pump (8) are connected via a third pipeline (103), and the chemical cleaning pipeline (26) is connected to the third pipeline (103) via a cleaning high-pressure pneumatic valve (33); A small amount of cleaning liquid coming out of the STRO membrane group (10) passes through the fifth pipeline (105) and the water production end cleaning liquid return pneumatic valve (27) into the cleaning tank; Most of the cleaning liquid coming out of the STRO membrane group (10) enters the cleaning tank through the concentrated liquid membrane outlet pipeline (15), the pressure regulating valve (23), and the concentrated liquid end cleaning liquid return pneumatic valve (28); The control system is respectively connected to the cleaning high-pressure pneumatic valve (33), the water production end cleaning liquid return pneumatic valve (27), and the concentrated liquid end cleaning liquid return pneumatic valve (28).

4. The reverse osmosis treatment system according to claim 2, characterized in that: It also includes a flushing pneumatic valve (29), the flushing pneumatic valve (29) being installed on the sixth pipeline (106), the raw water booster pump (1) being connected to the precision filter (3) via the first pipeline (101), and the sixth pipeline (106) being connected to the first pipeline (101); The flushing water enters from the sixth pipeline (106) to flush the STRO membrane group (10), and a small portion of the flushing water enters the wastewater tank through the fourth pipeline (104), the fifth pipeline (105), and the wastewater exhaust actuation valve (30) at the water production end; Most of the flushing water after flushing is discharged into the wastewater pool through the concentrate outlet pipeline (15), the high-pressure concentrate inlet pipeline (18), the pressure regulating valve (23), and the concentrate end wastewater exhaust actuating valve (31); The control system is respectively connected to the flushing pneumatic valve (29), the waste water exhaust pneumatic valve (30) at the water production end, and the waste water exhaust pneumatic valve (31) at the concentrated liquid end.

5. The reverse osmosis treatment system according to claim 2, characterized in that: The precision filter (3) is connected to the plunger pump (5) via a second pipeline (102); part of the low-pressure raw liquid in the second pipeline (102) enters the second inlet of the energy recovery device (19) through the low-pressure raw liquid inlet pipeline (21), is pressurized, and then comes out from the second outlet of the energy recovery device (19) and enters the inlet of the circulation pump (8) through the high-pressure raw liquid outlet pipeline (20).

6. The reverse osmosis treatment system according to claim 1, characterized in that: The raw water booster pump (1) is connected to the precision filter (3) via a first pipeline (101), the dosing device is connected to the first pipeline (101) via a dosing pipeline (32), a water inlet pump rear instrument assembly (2) is also provided on the first pipeline (101), a water production instrument assembly (12) is provided on the fifth pipeline (105), and the water inlet pump rear instrument assembly (2) includes at least one of the following detection components: Flow meter; Conductivity meter; Pressure transmitter; Pressure gauge; Temperature sensor; The water production meter assembly (12) comprises at least one of the following detection components: Flow meter; Pressure transmitter; Pressure gauge; Temperature sensor.

7. A chemical cleaning method for a reverse osmosis treatment system, characterized in that: The reverse osmosis treatment system described in claim 3 comprises the following steps: Step 1: Open the cleaning high-pressure pneumatic valve (33), the internal circulation pressure reducing valve (17), the water production end cleaning liquid return pneumatic valve (27), the pressure regulating valve (23), and the concentrated liquid end cleaning liquid return pneumatic valve (28); Step 2: The chemical cleaning liquid enters the STRO membrane group (10) through the chemical cleaning pipeline (26) via the circulation pump (8), and the cleaning liquid coming out of the STRO membrane group (10) first returns to the inlet of the circulation pump (8) via the internal circulation pipeline (16) and then enters the STRO membrane group (10) again to realize internal circulation cleaning; Step 3: After the cleaning reaches the set time, a small portion of the cleaning liquid coming out of the STRO membrane group (10) returns to the cleaning tank through the cleaning liquid reflux pneumatic valve (27), and most of the cleaning liquid coming out of the STRO membrane group (10) returns to the cleaning tank through the concentrated liquid membrane outlet pipeline (15), the pressure regulating valve (23), and the concentrated liquid end cleaning liquid reflux pneumatic valve (28).

8. A method for flushing a reverse osmosis treatment system, characterized in that: The reverse osmosis treatment system described in claim 4 comprises the following steps: S1: Open the flushing pneumatic valve (29), the internal circulation pressure reducing valve (17), the waste water exhaust pneumatic valve (30) at the water production end, the pressure regulating valve (23), and the waste water exhaust pneumatic valve (31) at the concentrate end; S2: flushing water passes through the flushing pneumatic valve (29), the precision filter (3), the plunger pump (5), and the circulation pump (8) into the STRO membrane group (10) for flushing. The flushing liquid from the STRO membrane group (10) first returns to the inlet of the circulation pump (8) through the internal circulation pipeline (16) and then enters the STRO membrane group (10) again to realize internal circulation flushing. S3: After the cleaning reaches the set time, a small portion of the flushing water from the STRO membrane group (10) is discharged to the wastewater pool through the water production end wastewater exhaust actuating valve (30); most of the flushing water from the STRO membrane group (10) is discharged to the wastewater pool through the concentrate outlet pipeline (15, the pressure regulating valve (23), and the concentrate end wastewater exhaust actuating valve (31).

9. An energy recovery method for a reverse osmosis treatment system, characterized in that: Using the reverse osmosis treatment system described in claim 5, the energy recovery method is: Part of the concentrated liquid that passes through the concentrated liquid membrane outlet pipeline (15) enters the energy recovery device (19) through the high-pressure concentrated liquid inlet pipeline (18) and undergoes energy conversion. The high-pressure concentrated liquid can drive the turbine at one end of the energy recovery device (19) to rotate so that the high-pressure water energy is converted into mechanical energy. The rotating mechanical energy can drive the turbine at the other end of the energy recovery device (19) to rotate and absorb the raw liquid. The raw liquid enters the second inlet of the energy recovery device (19) through the low-pressure raw liquid inlet pipeline (21) and is pressurized before exiting from the second outlet of the energy recovery device (19) to complete the energy conversion.

10. A method for filtering raw liquid of a reverse osmosis treatment system, characterized in that: The reverse osmosis treatment system described in claim 1 comprises the following steps: M1: Open the water production pneumatic valve (14), the internal circulation pressure reducing valve (17), the pressure regulating valve (23), and the concentrated liquid exhaust pneumatic valve (25); M2: Start the raw water booster pump (1) to deliver the raw water to the STRO membrane group (10) through the precision filter (3), the plunger pump (5) and the circulation pump (8), wherein the amount of water required by the STRO membrane group (10) includes a portion of the concentrated liquid at the outlet of the STRO membrane group (10) that flows back to the inlet of the circulation pump (8); M3: The STRO membrane group (10) separates the raw water under high pressure. The water output from the STRO membrane group (10) is divided into two parts: concentrated liquid and permeate. The permeate produced by each group of the STRO membrane groups (10) is discharged through the fifth pipeline (105) and the water production pneumatic valve (14). The concentrated liquid of each group of the STRO membrane groups (10) is collected and discharged through the concentrated liquid membrane outlet pipeline (15). Part of the discharged concentrated liquid enters the internal circulation process and returns to the STRO membrane group (10) to participate in production, and the other part enters the energy recovery device (19) to participate in energy conversion before being discharged.

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