High-rate concentration method and system for strong brine and readable storage medium

Abstract

The invention provides a high-magnification concentration method and system for strong brine and a readable storage medium, and the method comprises the following steps: firstly, carrying out primary membrane concentration treatment on the strong brine to obtain primary concentrated water; and conveying the first-stage concentrated water to a hollow fiber membrane concentration unit for second-stage membrane concentration treatment to obtain second-stage concentrated water. According to the high-magnification concentration method and system for strong brine and the readable storage medium, the osmotic pressure difference between the two sides of the membrane can be reduced through the hollow fiber membrane concentration unit, and the pressure needed in the membrane treatment process is reduced, so that the system operation energy consumption and the system operation cost can be reduced, and the energy consumption is reduced. High-power concentration of the strong brine under a low-pressure condition can be realized, and the TDS value of the strong brine can be effectively improved. In addition, produced water obtained after the first-stage concentrated water is subjected to second-stage membrane concentration treatment through the hollow fiber membrane concentration unit and part of refluxed second-stage concentrated water are in cross flow in the membrane assembly, and enrichment of pollutants on the membrane surface can be reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of water treatment, and in particular to a high-rate concentration method and system for concentrated brine, and a readable storage medium. Background Art

[0002] In zero wastewater discharge projects, nanofiltration water has a low salt content (generally less than 40,000 mg / L) and usually needs to be concentrated before entering the evaporation and crystallization system. Currently, common concentration methods include reverse osmosis, nanofiltration, electrodialysis, and evaporation concentration. The main methods for concentrating nanofiltration water are spiral reverse osmosis and electrodialysis.

[0003] Electrodialysis offers a high concentration factor, with the TDS of the concentrate reaching approximately 200,000 mg / L. However, practical applications present numerous challenges. These include the inability to remove organic matter and bacteria from the water, high energy consumption, poor desalination rates, complex cleaning, and easy wear and tear on the membrane elements. Furthermore, after electrodialysis concentrates the nanofiltration water, the salinity on the product side is typically over 10,000 mg / L, failing to meet the quality requirements for high-quality reclaimed water. This typically requires further treatment using reverse osmosis or recirculation to the front-end for further treatment. However, this latter treatment can lead to the accumulation of contaminants.

[0004] Currently, the most widely used concentration method for nanofiltration water production concentration is spiral reverse osmosis. Traditional spiral reverse osmosis systems operate at a pressure of around 40 bar, and the brine TDS can only reach 40,000-50,000 mg / L. Seawater reverse osmosis (SWRO) systems increase the operating pressure to 60-70 bar, but the brine TDS can only reach around 70,000 mg / L. High-pressure reverse osmosis (HPRO) systems increase the operating pressure to 110-120 bar, but the brine TDS can only reach around 120,000 mg / L.

[0005] Therefore, how to achieve high concentration of nanofiltration water under low pressure conditions and reduce system operating costs has become one of the technical problems that technicians in this field urgently need to solve. Summary of the Invention

[0006] The object of the present invention is to provide a high-rate concentration method, system and readable storage medium for brine to solve one or more problems existing in the prior art, such as the difficulty in achieving high-rate concentration of nanofiltration water under low-pressure conditions, high system operating costs, and pollutant enrichment.

[0007] To achieve the above object, the present invention is implemented through the following technical solutions: A high-rate concentration method for concentrated brine, comprising:

[0008] Performing a primary membrane concentration treatment on the concentrated brine to obtain primary concentrated water;

[0009] The primary concentrated water is transported to a hollow fiber membrane concentration unit for secondary membrane concentration treatment to obtain secondary concentrated water.

[0010] Optionally, the brine is subjected to a primary membrane concentration treatment to obtain primary concentrated water, including: storing the brine in a regulating tank, filtering the brine in the regulating tank to obtain a first effluent, and controlling the silt density index of the first effluent to be lower than a preset value; conveying the first effluent to a disc-tube reverse osmosis component for pre-concentration treatment, and controlling the operating pressure of the disc-tube reverse osmosis component to be within a first preset pressure range to obtain the primary concentrated water.

[0011] Optionally, the hollow fiber membrane concentration unit includes several hollow fiber reverse osmosis membrane assemblies connected in series, each of the hollow fiber reverse osmosis membrane assemblies having a concentrate inlet, a concentrate outlet, a reflux port and a produced water outlet, the concentrate outlet between two adjacent hollow fiber reverse osmosis membrane assemblies is connected to the concentrate inlet, and the reflux port between two adjacent hollow fiber reverse osmosis membrane assemblies is connected to the produced water outlet; the primary concentrate is transported to the hollow fiber membrane concentration unit for secondary membrane concentration treatment to obtain secondary concentrate, comprising: transporting the primary concentrate to the concentrate inlet of the hollow fiber reverse osmosis membrane assembly at the treatment front end in the hollow fiber membrane concentration unit and performing secondary membrane concentration treatment, outputting the secondary concentrate from the concentrate outlet of the hollow fiber reverse osmosis membrane assembly at the treatment end in the hollow fiber membrane concentration unit; transporting a portion of the secondary concentrate to the reflux port of the hollow fiber reverse osmosis membrane assembly at the treatment end, and outputting the produced water from the produced water outlet of the hollow fiber reverse osmosis membrane assembly at the treatment front end to the regulating tank.

[0012] Optionally, the concentration method further includes: before conveying the primary concentrated water to the hollow fiber membrane concentration unit, conveying the primary concentrated water to a pressure stabilizing tank and a high-pressure pump in sequence, so that the water inlet pressure of the hollow fiber membrane concentration unit is controlled within a second preset pressure range.

[0013] To achieve the above-mentioned purpose, the present invention also provides a high-rate concentration system for concentrated brine, the concentration system comprising a primary membrane concentration unit and a hollow fiber membrane concentration unit arranged in sequence; the primary membrane concentration unit is configured to perform a primary membrane concentration treatment on the concentrated brine to obtain primary concentrated water; the hollow fiber membrane concentration unit is configured to perform a secondary membrane concentration treatment on the primary concentrated water to obtain secondary concentrated water.

[0014] Optionally, the first-stage membrane concentration unit includes a regulating tank, a water inlet pump, a safety filter and a disc-tube reverse osmosis assembly arranged in sequence; the regulating tank is used to store the concentrated brine; the water inlet pump is used to transport the concentrated brine in the regulating tank to the safety filter; the safety filter is configured to: filter the concentrated brine to obtain a first effluent, and control the silt density index of the first effluent to be lower than a preset value; the disc-tube reverse osmosis assembly is configured to: pre-concentrate the first effluent, and control the operating pressure of the disc-tube reverse osmosis assembly within a first preset pressure range to obtain the first-stage concentrated water.

[0015] Optionally, the hollow fiber membrane concentration unit includes several hollow fiber reverse osmosis membrane assemblies connected in series, each of the hollow fiber reverse osmosis membrane assemblies having a concentrate inlet, a concentrate outlet, a reflux port and a produced water outlet, the concentrate outlet between two adjacent hollow fiber reverse osmosis membrane assemblies is connected to the concentrate inlet, and the reflux port between two adjacent hollow fiber reverse osmosis membrane assemblies is connected to the produced water outlet; the concentrate inlet of the hollow fiber reverse osmosis membrane assembly located at the front end of the treatment is connected to the concentrate output end of the disc-tube reverse osmosis assembly to receive the primary concentrate; the concentrate outlet of the hollow fiber reverse osmosis assembly located at the end of the treatment is used to discharge the secondary concentrate obtained after the secondary membrane concentration treatment, and is used to communicate with the reflux port of the hollow fiber reverse osmosis assembly located at the end of the treatment so that a portion of the secondary concentrate flows back to the reflux port of the hollow fiber reverse osmosis membrane assembly located at the end of the treatment; the produced water outlet of the hollow fiber reverse osmosis membrane assembly located at the front end of the treatment is connected to the regulating tank to output the produced water to the regulating tank.

[0016] Optionally, the reverse osmosis membrane of the hollow fiber reverse osmosis membrane assembly includes a hollow fiber membrane made of triacetyl cellulose.

[0017] Optionally, the concentration system further includes a pressure stabilizing tank and a high-pressure pump connected between the primary membrane concentration unit and the hollow fiber membrane concentration unit and arranged in sequence, so that the water inlet pressure of the hollow fiber membrane concentration unit is controlled within a second preset pressure range.

[0018] To achieve the above object, the present invention further provides a readable storage medium, wherein the readable storage medium stores a computer program, and when the computer program is executed by a processor, the high-rate concentration method of brine described in any one of the above items is implemented.

[0019] Compared with the prior art, the high-rate concentration method, system, and readable storage medium of brine provided by the present invention have the following beneficial effects:

[0020] The high-rate concentration method for concentrated brine provided by the present invention first performs a primary membrane concentration treatment on the concentrated brine to obtain primary concentrated water, which can initially increase the salt content of the concentrated brine; the primary concentrated water is then transported to a hollow fiber membrane concentration unit for secondary membrane concentration treatment to obtain secondary concentrated water. The hollow fiber membrane concentration unit can reduce the osmotic pressure difference between the two sides of the membrane, reducing the pressure required for the membrane treatment process, thereby not only reducing the system operating energy consumption and system operating costs, but also achieving high-rate concentration of concentrated brine under low-pressure conditions, which can effectively increase the TDS value of the concentrated brine. In addition, the produced water obtained after the primary concentrated water is subjected to secondary membrane concentration treatment by the hollow fiber membrane concentration unit and a portion of the refluxed secondary concentrated water present a cross-flow in the membrane assembly, which can reduce the enrichment of pollutants on the membrane surface.

[0021] Furthermore, the concentrated brine is subjected to a primary membrane concentration treatment to obtain a primary concentrated water, comprising: storing the concentrated brine in a regulating tank, filtering the concentrated brine in the regulating tank to obtain a first effluent, and controlling the silt density index of the first effluent to be lower than a preset value; conveying the first effluent to a disc-tube reverse osmosis component for pre-concentration treatment, and controlling the operating pressure of the disc-tube reverse osmosis component to be within a first preset pressure range to obtain the primary concentrated water. Thus, the high-rate concentration method for concentrated brine provided by the present invention can avoid clogging of subsequent disc-tube reverse osmosis components by filtering the concentrated brine and controlling the silt density index of the filtered first effluent to be lower than a preset value. By pre-concentrating the first effluent through the disc-tube reverse osmosis component and controlling the operating pressure of the disc-tube reverse osmosis component to be within a first preset pressure range, not only can impurities such as suspended matter in the first effluent be efficiently removed, laying a good foundation for improving the TDS value of concentrated water, but also the disc-tube reverse osmosis component is easy to maintain and simple to clean.

[0022] Since the high-rate concentration system for concentrated brine provided by the present invention and the readable storage medium provided by the present invention belong to the same inventive concept as the high-rate concentration method for concentrated brine provided by the present invention, the high-rate concentration system for concentrated brine provided by the present invention and the readable storage medium provided by the present invention have at least all the advantages of the high-rate concentration method for concentrated brine provided by the present invention. For the advantages of the high-rate concentration system for concentrated brine provided by the present invention and the readable storage medium provided by the present invention, please refer to the relevant description of the beneficial effects of the high-rate concentration method for concentrated brine provided by the present invention, which will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 A schematic diagram of the overall steps of a high-rate concentration method for concentrated brine provided in Example 1 of the present invention;

[0024] Figure 2A schematic diagram of a specific process of a high-rate concentration method for concentrated brine provided in Example 1 of the present invention;

[0025] Figure 3 This is a structural block diagram of a high-rate concentration system for concentrated brine provided in Example 2 of the present invention;

[0026] Figure 4 A process flow chart of a high-rate concentration system for concentrated brine provided in Example 2 of the present invention;

[0027] Figure 5 for Figure 4 Schematic diagram of the structure of the hollow fiber reverse osmosis membrane module;

[0028] Figure 6 A diagram showing a specific example of a hollow fiber membrane concentration unit provided in the second embodiment of the present invention;

[0029] Figure 7 A diagram showing the conductivity concentration effect of a hollow fiber membrane concentration unit provided in Example 2 of the present invention;

[0030] The following are the descriptions of the reference numerals:

[0031] 1-first-stage membrane concentration unit, 11-regulating tank, 12-water inlet pump, 13-security filter, 14-disc-tube reverse osmosis assembly, 2-hollow fiber membrane concentration unit, 21-hollow fiber reverse osmosis membrane assembly, 211-concentrated water inlet, 212-concentrated water outlet, 213-reflux port, 214-product water outlet, 3-pressure stabilizing tank, 4-high-pressure pump. DETAILED DESCRIPTION

[0032] The following is a detailed description of the high-rate brine concentration method, system, and readable storage medium proposed by the present invention, in conjunction with the accompanying drawings and specific embodiments. The advantages and features of the present invention will become more apparent from the following description. It should be noted that the drawings are in a very simplified form and are not to exact scale, and are only used to facilitate and clearly illustrate the purpose of the embodiments of the present invention. To make the purposes, features, and advantages of the present invention more readily apparent, please refer to the accompanying drawings. It should be noted that the structures, proportions, and sizes illustrated in the drawings of this specification are intended solely to facilitate understanding and reading by those skilled in the art, and are not intended to limit the implementation of the present invention. Any structural modifications, changes in proportions, or adjustments in size, provided that they produce the same or similar effects and achieve the same objectives as the present invention, shall still fall within the scope of the technical content disclosed herein. The specific design features of the present invention disclosed herein, including, for example, specific dimensions, orientations, positions, and shapes, will be determined in part by the specific application and use environment. Furthermore, in the embodiments described below, the same reference numerals may be used across different drawings to represent the same parts or parts having the same functions, and their repeated descriptions may be omitted.

[0033] Example 1

[0034] This embodiment provides a high-rate concentration method for concentrated brine. Figure 1 , Figure 1 The schematic diagram of the overall steps of the high-rate concentration method of concentrated brine provided in this embodiment. Figure 1 It can be seen that the concentration method comprises:

[0035] S100: performing a primary membrane concentration treatment on the concentrated brine to obtain primary concentrated water;

[0036] S200: The primary concentrated water is transported to the hollow fiber membrane concentration unit 2 for secondary membrane concentration treatment to obtain secondary concentrated water.

[0037] Therefore, the high-rate concentration method for concentrated brine provided in this embodiment first performs a primary membrane concentration treatment on the concentrated brine to obtain primary concentrated water, which can initially increase the salt content of the concentrated brine; the primary concentrated water is then transported to the hollow fiber membrane concentration unit 2 for secondary membrane concentration treatment to obtain secondary concentrated water. The hollow fiber membrane concentration unit 2 can reduce the osmotic pressure difference on both sides of the membrane and reduce the pressure required for the membrane treatment process, thereby not only reducing the system operating energy consumption and reducing the system operating cost, but also achieving high-rate concentration of concentrated brine under low pressure conditions, which can effectively increase the TDS value of the concentrated brine. In addition, the produced water obtained after the primary concentrated water is subjected to secondary membrane concentration treatment by the hollow fiber membrane concentration unit 2 and a portion of the refluxed secondary concentrated water present a cross-flow in the membrane assembly, which can reduce the enrichment of pollutants on the membrane surface.

[0038] It should be noted that the present invention does not impose any particular restrictions on the specific type of brine, which may be, but is not limited to, nanofiltration water. For example, in some exemplary embodiments, the brine has the following water quality characteristics: pH between 6 and 8, inlet temperature between 30°C and 40°C, COD less than 50 mg / L, residual chlorine content less than 2 mg / L, conductivity between 14,000 μS / cm and 43,000 μS / cm, and silt density index less than 4.

[0039] For example, see Figure 2 , Figure 2 The specific flow diagram of the high-rate concentration method of concentrated brine provided in this embodiment is as follows: Figure 2 As can be seen, in step S100, the concentrated brine is subjected to a primary membrane concentration process to obtain primary concentrated water, including: storing the concentrated brine in a regulating tank 11, filtering the concentrated brine in the regulating tank 11 to obtain a first effluent, and controlling the silt density index of the first effluent to be below a preset value; and conveying the first effluent to a disc-tube reverse osmosis module 14 for primary membrane concentration, and controlling the operating pressure of the disc-tube reverse osmosis module 14 to be within a first preset pressure range, to obtain the primary concentrated water. Thus, by filtering the concentrated brine and controlling the silt density index of the filtered first effluent to be below a preset value, clogging of the subsequent disc-tube reverse osmosis module 14 can be avoided. Pre-concentrating the first effluent through the disc-tube reverse osmosis module 14 and controlling the operating pressure of the disc-tube reverse osmosis module 14 within the first preset pressure range not only effectively removes suspended matter and other impurities from the first effluent, laying a good foundation for improving the TDS value of the concentrated water, but also makes the disc-tube reverse osmosis module 14 easy to maintain and simple to clean.

[0040] It should be noted that the present invention does not impose any particular restrictions on the preset value; it only requires that the first effluent after filtration does not cause clogging of the subsequent disc-tube reverse osmosis assembly 14. For example, in some exemplary embodiments, the preset value may be 4; in other embodiments, the preset value may also be 3.

[0041] It should be noted that the present invention does not impose any particular limitations on the value of the first preset pressure range. For example, in some embodiments, the first preset pressure range may be 75 bar to 120 bar, such that the conductivity of the primary concentrate obtained after the primary membrane concentration process is between 102,000 μS / cm and 150,000 μS / cm.

[0042] Preferably, the material of the disc-tube reverse osmosis membrane in the disc-tube reverse osmosis assembly 14 is polyvinylidene fluoride, and the pore size of the disc-tube reverse osmosis membrane is between 0.03 μm and 1.0 μm.

[0043] For example, please see Figure 2 ,from Figure 2 It can be seen that the hollow fiber membrane concentration unit 2 includes a plurality of hollow fiber reverse osmosis membrane assemblies 21 connected in series, each of the hollow fiber reverse osmosis membrane assemblies 21 having a concentrated water inlet 211, a concentrated water outlet 212, a reflux port 213 and a produced water outlet 214. The concentrated water outlet 212 between two adjacent hollow fiber reverse osmosis membrane assemblies 21 is connected to the concentrated water inlet 211, and the reflux port 213 between two adjacent hollow fiber reverse osmosis membrane assemblies 21 is connected to the produced water outlet 214. In step S200, the primary concentrated water is transported to the hollow fiber membrane concentration unit 2 for The secondary membrane concentration process, which produces secondary brine, includes: transporting the primary brine to the brine inlet 211 of the hollow fiber reverse osmosis membrane assembly 21 at the front end of the hollow fiber membrane concentration unit 2 for secondary membrane concentration, and outputting the secondary brine from the brine outlet 212 of the hollow fiber reverse osmosis membrane assembly 21 at the end of the treatment process in the hollow fiber membrane concentration unit 2; transporting a portion of the secondary brine to the reflux port 213 of the hollow fiber reverse osmosis membrane assembly 21 at the end of the treatment process, and outputting the produced water from the produced water outlet 214 of the hollow fiber reverse osmosis membrane assembly 21 at the front end of the treatment process to the regulating tank 11. Thus, by performing secondary membrane concentration on the primary brine through multiple hollow fiber reverse osmosis membrane assemblies 21 connected in series, high-fold concentration of the brine can be achieved, effectively increasing the TDS value of the brine. Furthermore, by transporting a portion of the secondary concentrated water to the reflux port 213 of the hollow fiber reverse osmosis membrane assembly 21 at the end of the treatment, and outputting the produced water from the produced water outlet 214 of the hollow fiber reverse osmosis membrane assembly 21 at the front end of the treatment to the regulating tank 11, the salt content of the produced water in the hollow fiber membrane concentration unit 2 can be increased, the osmotic pressure difference on both sides of the membrane can be reduced, and the pressure required for the membrane treatment process can be reduced, thereby achieving high-fold concentration of the concentrated brine under low-pressure conditions, and reducing the system operating energy consumption and system operating costs.

[0044] It should be noted that the number of hollow fiber reverse osmosis membrane modules 21 in the hollow fiber membrane concentration unit 2 can be set according to the concentration multiple requirement. For example, in some exemplary embodiments, 3-10 hollow fiber reverse osmosis membrane modules 21 are connected in series in the hollow fiber membrane concentration unit 2.

[0045] Please continue to see Figure 1 and Figure 2 ,from Figure 1 and Figure 2It can be seen that the concentration method further comprises:

[0046] S300: Before delivering the primary concentrated water to the hollow fiber membrane concentration unit 2, the primary concentrated water is delivered to the pressure stabilizing tank 3 and the high-pressure pump 4 in sequence, so that the water inlet pressure of the hollow fiber membrane concentration unit 2 is controlled within a second preset pressure range.

[0047] Therefore, by setting up a high-pressure pump 4, the water inlet pressure of the hollow fiber membrane concentration unit 2 can be controlled within the second preset pressure range, laying a good foundation for achieving high-fold concentration of concentrated brine under low-pressure conditions; by setting up a pressure-stabilizing tank 3, the start-stop frequency of the high-pressure pump 4 can be reduced, and the system pressure can be stabilized.

[0048] It should be noted that the present invention does not impose any particular limitations on the second preset pressure range. For example, in some embodiments, the second preset pressure range may be 60 bar to 75 bar, such that the conductivity of the secondary concentrate obtained after the secondary membrane concentration process is between 180,000 μS / cm and 260,000 μS / cm.

[0049] Example 2

[0050] This embodiment provides a high-rate concentration system for concentrated brine. Figure 3 , Figure 3 The structural block diagram of the high-rate concentration system of concentrated brine provided in this embodiment. Figure 3 It can be seen that the concentration system includes a primary membrane concentration unit 1 and a hollow fiber membrane concentration unit 2 arranged in sequence; the primary membrane concentration unit 1 is configured to perform a primary membrane concentration treatment on the concentrated brine to obtain primary concentrated water; the hollow fiber membrane concentration unit 2 is configured to perform a secondary membrane concentration treatment on the primary concentrated water to obtain secondary concentrated water.

[0051] For example, see Figure 4 , Figure 4 The process flow chart of the high-rate concentration system of concentrated brine provided in this embodiment. Figure 4As can be seen, the primary membrane concentration unit 1 comprises a regulating tank 11, an inlet pump 12, a safety filter 13, and a disc-tube reverse osmosis module 14, arranged in this order. The regulating tank 11 is used to store the concentrated brine. The inlet pump 12 is used to transport the concentrated brine from the regulating tank 11 to the safety filter 13. The safety filter 13 is configured to filter the concentrated brine to produce a first effluent, and to control the silt density index of the first effluent to be below a preset value. The disc-tube reverse osmosis module 14 is configured to pre-concentrate the first effluent and control the operating pressure of the disc-tube reverse osmosis module 14 within a first preset pressure range to produce the primary concentrated brine. Thus, the concentrated brine collected in the regulating tank 11 is transported by the inlet pump 12 to the safety filter 13 for filtration before entering the subsequent disc-tube reverse osmosis module 14. The silt density index of the first effluent is controlled to be below a preset value, thereby preventing clogging of the disc-tube reverse osmosis module 14.

[0052] For example, please see Figure 4 as well as Figure 5 and Figure 6 ,in, Figure 5 for Figure 4 Schematic diagram of the structure of the hollow fiber reverse osmosis membrane module; Figure 6 This is a specific example diagram of the hollow fiber membrane concentration unit provided in this embodiment. Figures 4 to 6 It can be seen that the hollow fiber membrane concentration unit 2 includes a plurality of hollow fiber reverse osmosis membrane assemblies 21 connected in series, each of the hollow fiber reverse osmosis membrane assemblies 21 having a concentrated water inlet 211, a concentrated water outlet 212, a reflux port 213 and a produced water outlet 214. The concentrated water outlet 212 between two adjacent hollow fiber reverse osmosis membrane assemblies 21 is connected to the concentrated water inlet 211, and the reflux port 213 between two adjacent hollow fiber reverse osmosis membrane assemblies 21 is connected to the produced water outlet 214. The concentrated water inlet of the hollow fiber reverse osmosis membrane assembly 21 located at the front end of the treatment is connected to the disc The concentrated water output end of the tubular reverse osmosis component 14 is connected to receive the primary concentrated water; the concentrated water outlet 212 of the hollow fiber reverse osmosis component located at the treatment end is used to discharge the secondary concentrated water obtained after the secondary membrane concentration treatment, and is used to communicate with the reflux port 213 of the hollow fiber reverse osmosis component located at the treatment end so that a portion of the secondary concentrated water flows back to the reflux port 213 of the hollow fiber reverse osmosis membrane component 21 located at the treatment end; the produced water outlet 214 of the hollow fiber reverse osmosis membrane component 21 located at the treatment front end is connected to the regulating tank 11 to output the produced water to the regulating tank 11.

[0053] Preferably, the reverse osmosis membrane of the hollow fiber reverse osmosis membrane assembly 21 includes a hollow fiber membrane made of triacetyl cellulose.

[0054] Furthermore, the concentration system also includes a pressure stabilizing tank 3 and a high-pressure pump 4 connected between the primary membrane concentration unit 1 and the hollow fiber membrane concentration unit 2 and arranged in sequence, so that the water inlet pressure of the hollow fiber membrane concentration unit 2 is controlled within a second preset pressure range.

[0055] Since the high-rate concentration system for concentrated brine provided in this embodiment and the high-rate concentration method for concentrated brine provided in any of the above-mentioned embodiments belong to the same inventive concept, the high-rate concentration system for concentrated brine provided in this embodiment has at least all the advantages of the high-rate concentration method for concentrated brine provided in the above-mentioned embodiments. For the advantages of the high-rate concentration system for concentrated brine provided in this embodiment, please refer to the relevant description of the beneficial effects of the high-rate concentration method for concentrated brine provided in the above-mentioned embodiments, which will not be repeated here.

[0056] In order to make the present invention more understandable, the following is exemplary Figure 3-Figure 7 The process of concentrating nanofiltration water using the high-rate concentration system for concentrated brine provided by the present invention is described; wherein, Figure 7 The conductivity concentration effect diagram of the hollow fiber membrane concentration unit 2 provided in this embodiment illustrates the concentration effect of four hollow fiber reverse osmosis membrane modules 21. The water quality characteristics of the nanofiltration product are: inlet temperature of 30°C-40°C, COD <30 mg / L, conductivity of 35,000 μS / cm-43,000 μS / cm, silt density index <4, and chloride ion concentration of 9,000 mg / L-10,000 mg / L. The number of hollow fiber reverse osmosis membrane modules 21 in the concentration system is four.

[0057] First, the nanofiltration concentrate from the regulating tank 11 is transferred via the inlet pump 12 to the safety filter 13 for filtration. The silt density index of the effluent from the safety filter 13 is controlled to be below 4, producing a primary effluent. The primary effluent is then transferred to the disc-tube reverse osmosis module 14 for pre-concentration, operating at a pressure of 100 bar. This produces a primary concentrate with a conductivity between 122,000 μS / cm and 127,000 μS / cm. This primary concentrate then enters the surge tank 3 and is transferred via the high-pressure pump 4 to the concentrate inlet of the hollow fiber reverse osmosis membrane module 21 at the front end of the treatment process. The outlet pressure of the high-pressure pump 4 is controlled between 60 bar and 75 bar. Finally, after concentration by the four hollow fiber reverse osmosis membrane modules 21 in the hollow fiber membrane concentration unit 2, the conductivity of the nanofiltration concentrate reaches 240,000 μS / cm, achieving a concentration factor of 1.97.

[0058] Depend on Figure 7As can be seen, the conductivity curve always has a maximum point. This is because as the solution concentration increases, the number of ions per unit volume increases, and the conductivity also increases accordingly. However, after the solution concentration reaches a certain value, the conductivity actually decreases due to the enhanced interaction between ions or the reduced degree of electrolyte dissociation. Therefore, the conductivity concentration factor shows a trend of gradually decreasing with increasing salt concentration.

[0059] Example 3

[0060] This embodiment provides a readable storage medium, in which a computer program is stored. When the computer program is executed by a processor, the high-rate concentration method of brine described in any of the above embodiments is implemented.

[0061] Since the readable storage medium provided in this embodiment and the high-rate concentration method for concentrated brine provided in any of the above-mentioned embodiments belong to the same inventive concept, the readable storage medium provided in this embodiment has at least all the advantages of the high-rate concentration method for concentrated brine provided in the above-mentioned embodiments. For the advantages of the readable storage medium provided in this embodiment, please refer to the relevant description of the beneficial effects of the high-rate concentration method for concentrated brine provided in the above-mentioned embodiments, which will not be repeated here.

[0062] In summary, the high-rate concentration method, system and readable storage medium of brine provided by the present invention have the following advantages: the high-rate concentration method of brine provided by the present invention first performs a primary membrane concentration treatment on the brine to obtain primary concentrated water, which can preliminarily increase the salt content of the brine; the primary concentrated water is then transported to the hollow fiber membrane concentration unit for secondary membrane concentration treatment to obtain secondary concentrated water. The hollow fiber membrane concentration unit can reduce the osmotic pressure difference on both sides of the membrane and reduce the pressure required for the membrane treatment process, thereby not only reducing the system operating energy consumption and reducing the system operating cost, but also achieving high-rate concentration of brine under low pressure conditions, which can effectively increase the TDS value of brine. In addition, the produced water obtained after the primary concentrated water is subjected to secondary membrane concentration treatment by the hollow fiber membrane concentration unit and a portion of the refluxed secondary concentrated water present a cross-flow in the membrane assembly, which can reduce the enrichment of pollutants on the membrane surface.

[0063] Furthermore, the concentrated brine is subjected to a primary membrane concentration treatment to obtain a primary concentrated water, comprising: storing the concentrated brine in a regulating tank, filtering the concentrated brine in the regulating tank to obtain a first effluent, and controlling the silt density index of the first effluent to be lower than a preset value; conveying the first effluent to a disc-tube reverse osmosis component for pre-concentration treatment, and controlling the operating pressure of the disc-tube reverse osmosis component to be within a first preset pressure range to obtain the primary concentrated water. Thus, the high-rate concentration method for concentrated brine provided by the present invention can avoid clogging of subsequent disc-tube reverse osmosis components by filtering the concentrated brine and controlling the silt density index of the filtered first effluent to be lower than a preset value. By pre-concentrating the first effluent through the disc-tube reverse osmosis component and controlling the operating pressure of the disc-tube reverse osmosis component to be within a first preset pressure range, not only can impurities such as suspended matter in the first effluent be efficiently removed, laying a good foundation for improving the TDS value of concentrated water, but also the disc-tube reverse osmosis component is easy to maintain and simple to clean.

[0064] Since the high-rate concentration system for concentrated brine provided by the present invention and the readable storage medium provided by the present invention belong to the same inventive concept as the high-rate concentration method for concentrated brine provided by the present invention, the high-rate concentration system for concentrated brine provided by the present invention and the readable storage medium provided by the present invention have at least all the advantages of the high-rate concentration method for concentrated brine provided by the present invention. For the advantages of the high-rate concentration system for concentrated brine provided by the present invention and the readable storage medium provided by the present invention, please refer to the relevant description of the beneficial effects of the high-rate concentration method for concentrated brine provided by the present invention, which will not be repeated here.

[0065] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not limiting. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention.

Claims

1. A high-rate concentration method for concentrated brine, characterized in that: The concentration method comprises: Performing a primary membrane concentration treatment on the concentrated brine to obtain primary concentrated water; The primary concentrated water is transported to a hollow fiber membrane concentration unit for secondary membrane concentration treatment to obtain secondary concentrated water.

2. The high-rate concentration method for concentrated brine according to claim 1, wherein: The concentrated brine is subjected to a primary membrane concentration process to obtain primary concentrated water, comprising: storing the concentrated brine in a regulating tank, filtering the concentrated brine in the regulating tank to obtain a first effluent, and controlling the silt density index of the first effluent to be lower than a preset value; The first effluent is transported to a disc-tube reverse osmosis assembly for pre-concentration treatment, and the operating pressure of the disc-tube reverse osmosis assembly is controlled within a first preset pressure range to obtain the primary concentrated water.

3. The high-rate concentration method for concentrated brine according to claim 2, wherein: The hollow fiber membrane concentration unit includes a plurality of hollow fiber reverse osmosis membrane modules connected in series, each of the hollow fiber reverse osmosis membrane modules having a concentrated water inlet, a concentrated water outlet, a reflux port, and a produced water outlet. The concentrated water outlet between two adjacent hollow fiber reverse osmosis membrane modules is connected to the concentrated water inlet, and the reflux port between two adjacent hollow fiber reverse osmosis membrane modules is connected to the produced water outlet. The step of transporting the primary concentrated water to a hollow fiber membrane concentration unit for secondary membrane concentration treatment to obtain secondary concentrated water comprises: The primary concentrated water is transported to the concentrated water inlet of the hollow fiber reverse osmosis membrane module at the treatment front end of the hollow fiber membrane concentration unit and subjected to secondary membrane concentration treatment, and the secondary concentrated water is output from the concentrated water outlet of the hollow fiber reverse osmosis membrane module at the treatment end of the hollow fiber membrane concentration unit; A portion of the secondary concentrated water is transported to the reflux port of the hollow fiber reverse osmosis membrane assembly at the treatment end, and the produced water is output from the produced water outlet of the hollow fiber reverse osmosis membrane assembly at the treatment front end to the regulating tank.

4. The high-rate concentration method for concentrated brine according to claim 2, wherein: The concentration method further comprises: Before the primary concentrated water is transported to the hollow fiber membrane concentration unit, the primary concentrated water is sequentially transported to a pressure stabilizing tank and a high-pressure pump, so that the water inlet pressure of the hollow fiber membrane concentration unit is controlled within a second preset pressure range.

5. A high-rate concentration system for concentrated brine, characterized in that: The concentration system comprises a primary membrane concentration unit and a hollow fiber membrane concentration unit arranged in sequence; The primary membrane concentration unit is configured to perform a primary membrane concentration process on the concentrated brine to obtain primary concentrated water; The hollow fiber membrane concentration unit is configured to perform a secondary membrane concentration process on the primary concentrated water to obtain secondary concentrated water.

6. The high-rate concentration system for concentrated brine according to claim 5, characterized in that: The first-level membrane concentration unit includes a regulating tank, a water inlet pump, a safety filter and a disc-tube reverse osmosis component arranged in sequence; The regulating tank is used to store the concentrated brine; The water inlet pump is used to transport the concentrated brine in the regulating tank to the safety filter; The security filter is configured to: filter the concentrated brine to obtain a first effluent, and control the silt density index of the first effluent to be lower than a preset value; The disc-tube reverse osmosis module is configured to perform pre-concentration treatment on the first effluent and control the operating pressure of the disc-tube reverse osmosis module within a first preset pressure range to obtain the primary concentrated water.

7. The high-rate concentration system for concentrated brine according to claim 6, characterized in that: The hollow fiber membrane concentration unit includes a plurality of hollow fiber reverse osmosis membrane modules connected in series, each of the hollow fiber reverse osmosis membrane modules having a concentrated water inlet, a concentrated water outlet, a reflux port, and a produced water outlet. The concentrated water outlet between two adjacent hollow fiber reverse osmosis membrane modules is connected to the concentrated water inlet, and the reflux port between two adjacent hollow fiber reverse osmosis membrane modules is connected to the produced water outlet. The concentrate inlet of the hollow fiber reverse osmosis membrane assembly at the front end of the treatment process is connected to the concentrate output end of the disc-tube reverse osmosis assembly to receive the primary concentrate; the concentrate outlet of the hollow fiber reverse osmosis assembly at the end of the treatment process is used to discharge the secondary concentrate obtained after the secondary membrane concentration treatment, and is used to communicate with the reflux port of the hollow fiber reverse osmosis assembly at the end of the treatment process so that a portion of the secondary concentrate flows back to the reflux port of the hollow fiber reverse osmosis membrane assembly at the end of the treatment process; The produced water outlet of the hollow fiber reverse osmosis membrane assembly located at the front end of the treatment is connected to the regulating tank to output the produced water to the regulating tank.

8. The high-rate concentration system for concentrated brine according to claim 7, characterized in that: The reverse osmosis membrane of the hollow fiber reverse osmosis membrane module includes a hollow fiber membrane made of triacetyl cellulose.

9. The high-rate concentration system for concentrated brine according to claim 5, characterized in that: The concentration system further includes a pressure stabilizing tank and a high-pressure pump connected between the primary membrane concentration unit and the hollow fiber membrane concentration unit and arranged in sequence, so that the water inlet pressure of the hollow fiber membrane concentration unit is controlled within a second preset pressure range.

10. A readable storage medium, characterized in that: The readable storage medium stores a computer program, and when the computer program is executed by a processor, the high-rate concentration method of the concentrated brine according to any one of claims 1 to 4 is implemented.

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