Boiler make-up water treatment system and method based on modified reverse osmosis membrane

Abstract

The invention discloses a boiler make-up water treatment system and method based on a modified reverse osmosis membrane, and belongs to the technical field of water treatment systems. The treatment system comprises a pretreatment unit, a reverse osmosis unit, a resin unit, a TOC online detection unit, an early warning unit, a reverse osmosis membrane modification unit and a modified reverse osmosis membrane regeneration unit. The treatment method comprises the following steps: S1, pretreatment; s2, primary reverse osmosis; s3, secondary reverse osmosis; s4, resin adsorption; s5, carrying out TOC (Total Organic Carbon) online analysis; and S6, regeneration treatment. Different reverse osmosis membrane modifications are carried out on primary reverse osmosis and secondary reverse osmosis, so that membrane surface characteristics of the two stages of reverse osmosis are respectively changed, and organic matters with different electrification characteristics in raw water are treated; the reverse osmosis membrane is modified, so that the density of a reverse osmosis membrane separation layer is increased, and the separation effect on organic matters is improved. The modified effluent effect and water quality are monitored in real time through the early warning system, the performance change of the modified reverse osmosis membrane is found in time, and the modified reverse osmosis membrane is regenerated.

Description

Technical Field

[0001] The invention belongs to the technical field of water treatment systems, and in particular relates to a boiler feed water treatment system and method based on a modified reverse osmosis membrane. Background Art

[0002] Boilers play a key role in thermal power generation. After a long period of theoretical and practical experience, people have come to realize that the quality of boiler feed water is a key factor in ensuring its safe and economical operation. Boilers usually use two water sources: one is untreated natural water, such as groundwater, mountain spring water or reservoir water; the other is wastewater treated by industrial reuse water stations. Although the latter has been treated, it still contains a high concentration of salt, especially chloride ions, sodium ions, ammonium ions, a certain amount of organic matter, and a small amount of calcium ions and magnesium ions. At the same time, untreated natural water contains a variety of impurities, such as salt and microorganisms. Poor water quality for boilers will lead to widespread scaling and corrosion problems on the heating surface. If the salt content of treated water is still high, it may cause steam to carry water and steam-water co-boiling, which will not only increase the amount of sewage discharged, but also affect the safe and economical operation of the boiler. Therefore, it is of great practical significance and urgency to effectively treat the boiler water quality to ensure that it meets the appropriate standards.

[0003] Traditional boiler feed water treatment processes mainly include coagulation, sedimentation, ultrafiltration pretreatment units, and reverse osmosis and ion exchange resin desalination units. The purpose of pretreatment is to remove large particulate matter, suspended matter and some dissolved solids in the water to protect subsequent equipment. Reverse osmosis treatment, which is a highly efficient desalination technology, separates salt and other dissolved substances in the water by applying pressure to force water molecules through a semipermeable membrane. Reverse osmosis can significantly reduce the total dissolved solids (TDS) and total organic carbon (TOC) of water and improve water quality. Finally, resin treatment, also known as ion exchange, is used to remove remaining hardness ions (such as calcium and magnesium) in the water, as well as some dissolved salts. The resin bed can adsorb these ions, thereby softening the water and reducing the risk of boiler scaling. The entire treatment process requires precise control to ensure that the final feed water meets the safe and economical operation requirements of the boiler.

[0004] The traditional boiler feed water treatment process of thermal power plants can ensure that its salt content meets the national standard requirements. However, as organic pollution in water sources becomes increasingly serious, the performance of reverse osmosis membranes is reduced due to excessive cleaning times. Traditional boiler feed water treatment processes often have problems with excessive organic concentration in effluent water. After organic matter enters the boiler, it changes under high temperature and high pressure, producing some substances that can cause corrosion of metal materials in boilers and steam turbine units.

[0005] The removal of organic matter in traditional boiler feed water treatment processes mainly relies on the removal effect of reverse osmosis membranes. Generally, reverse osmosis membranes have a relatively high removal rate for organic matter, but the general reverse osmosis membrane has a poor removal ability for small molecular organic matter. Usually, organic matter that cannot be removed by the first-stage reverse osmosis cannot be removed by the second or even more stages of reverse osmosis, and eventually enters the reverse osmosis water production side.

[0006] Therefore, as the concentration of organic matter in the influent increases, the complexity of the pollutant composition often results in the effluent TOC failing to meet the standards. Summary of the invention

[0007] The present invention aims at the following phenomena: the conventional boiler feed water treatment process has poor ability to remove small molecule organic matter by reverse osmosis, and the two-stage or even multi-stage reverse osmosis has no differentiated removal of organic matter, resulting in failure to remove organic matter of certain characteristics. Thus, a boiler feed water treatment system and method based on a modified reverse osmosis membrane is provided to solve the problem of excessive TOC concentration in effluent from the conventional boiler feed water treatment process.

[0008] The technical solution adopted by the present invention is:

[0009] A boiler feed water treatment system based on modified reverse osmosis membrane, comprising

[0010] A pretreatment unit, connected to the reverse osmosis unit, for pretreating the raw water to be treated;

[0011] A reverse osmosis unit, connected to the resin unit, for performing reverse osmosis treatment on the raw water to be treated;

[0012] The resin units are respectively connected to the desalination water tanks and used for mixed-bed resin treatment of the reverse osmosis water;

[0013] TOC online detection unit, used for online TOC analysis of desalinated water;

[0014] The early warning unit is connected to the TOC online detection unit.

[0015] A reverse osmosis membrane modification unit is connected to the reverse osmosis unit and is controlled by the early warning unit, and is used to modify the reverse osmosis membrane in the reverse osmosis unit;

[0016] The modified reverse osmosis membrane regeneration unit is connected to the reverse osmosis unit and is controlled by the early warning unit, and is used for regenerating the modified reverse osmosis membrane in the reverse osmosis unit.

[0017] A method for treating boiler feed water based on a modified reverse osmosis membrane comprises the following steps:

[0018] S1. Pretreatment: remove suspended solid particles including colloids in raw water to obtain pretreated effluent;

[0019] S2. Primary reverse osmosis: The pretreated effluent is subjected to primary reverse osmosis treatment based on a modified reverse osmosis membrane to obtain primary reverse osmosis treated water;

[0020] S3. Secondary reverse osmosis: The primary reverse osmosis product water is subjected to secondary reverse osmosis treatment based on a second type modified reverse osmosis membrane to obtain reverse osmosis product water;

[0021] S4. Resin adsorption: The reverse osmosis water is treated with mixed bed resin to obtain desalinated water;

[0022] S5.TOC online analysis: Perform TOC online analysis on the desalination water. If (TOCt1-TOCt0) / TOCt0>25%, enter S6, otherwise the desalination water enters the desalination water tank, where t0 is the initial time of the system, t1 is the current time, TOCt0 is the TOC of the water at the initial time of the system, and TOCt1 is the TOC of the water at the current time;

[0023] S6. Regeneration treatment: regenerating the first type modified reverse osmosis membrane and the second type modified reverse osmosis membrane.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] 1. The present invention makes different modifications to the reverse osmosis membranes of the first-stage reverse osmosis and the second-stage reverse osmosis, so that the surface characteristics of the membranes of the two stages are changed respectively, and they have different surface charge characteristics, respectively, and treat organic matter with different charge characteristics in the raw water; by modifying the reverse osmosis membrane, the density of the separation layer of the reverse osmosis membrane is increased, and the separation effect of the organic matter is increased.

[0026] 2. The present invention monitors the water quality of the modified effluent in real time through an early warning system, promptly discovers changes in the performance of the modified reverse osmosis membrane, and regenerates the modified reverse osmosis membrane. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic diagram of the structure of the processing system of the present invention;

[0028] Figure 2 is a flow chart of the processing method of the present invention;

[0029] Figure 3 This is a flow chart of a modified reverse osmosis membrane modification method of the present invention;

[0030] Figure 4 It is a flow chart of the modification method of the second type of modified reverse osmosis membrane of the present invention;

[0031] Figure 5 This is a flow chart of the regeneration process of the modified reverse osmosis membrane of the present invention;

[0032] Among them: 1. Pretreatment unit; 2. Reverse osmosis unit; 3. Reverse osmosis membrane modification unit; 4. Resin unit; 5. TOC online detection unit; 6. Early warning unit; 7. Modified reverse osmosis membrane regeneration unit; 201. Primary reverse osmosis module; 202. Secondary reverse osmosis module. DETAILED DESCRIPTION

[0033] In order to better understand the purpose, structure and function of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings.

[0034] The present invention is based on reverse osmosis treatment. The reverse osmosis membrane is modified to increase the density of the reverse osmosis membrane separation layer and improve the separation effect of organic matter. Two-stage or multi-stage reverse osmosis uses different modification methods to change the membrane surface characteristics to treat organic matter with different charged characteristics in raw water. At the same time, the effluent water quality is monitored in real time through an early warning system to timely discover changes in the performance of the modified reverse osmosis membrane and regenerate the modified reverse osmosis membrane, so that the TOC of the system effluent meets the index.

[0035] like Figure 1 As shown, the present invention provides a boiler feed water treatment system based on a modified reverse osmosis membrane, comprising

[0036] A pretreatment unit 1, connected to the reverse osmosis unit 2, for pretreating the raw water to be treated;

[0037] The reverse osmosis unit 2 is connected to the resin unit 4 and is used to perform reverse osmosis treatment on the raw water to be treated;

[0038] The resin units 4 are respectively connected to the desalination water tanks and are used for mixed bed resin treatment of the reverse osmosis water;

[0039] TOC online detection unit 5, used for online TOC analysis of desalinated water; its installation location is determined according to the actual situation of the factory, as long as it can detect desalinated water;

[0040] The early warning unit 6 is connected to the TOC online detection unit 5.

[0041] The reverse osmosis membrane modification unit 3 is connected to the reverse osmosis unit 2 and is controlled by the early warning unit 6, and is used to modify the reverse osmosis membrane in the reverse osmosis unit 2;

[0042] The modified reverse osmosis membrane regeneration unit 7 is connected to the reverse osmosis unit 2 and is controlled by the early warning unit 6 , and is used for regenerating the modified reverse osmosis membrane in the reverse osmosis unit 2 .

[0043] The pretreatment unit 1 includes a coagulation system, a sedimentation system, and a filtration system, wherein the coagulation system includes a fast mixing module and a slow mixing module, and the filtration system includes sand filtration and ultrafiltration.

[0044] The pretreatment unit 1 also includes a softening module before the coagulation system.

[0045] The reverse osmosis membrane modification unit 3 includes a first module, a second module, and a third module; the first modification agent box water outlet of the first module, the second modification agent box water outlet of the second module, and the third modification agent box water outlet of the third module are connected, and the water outlets are all provided with switching valves;

[0046] The first module includes a first modified reagent tank and a first reagent dosing pump connected to the first modified reagent tank, the second module includes a second modified reagent tank and a second reagent dosing pump connected to the second modified reagent tank, and the third module includes a third modified reagent tank and a third reagent dosing pump connected to the third modified reagent tank.

[0047] like Figure 1 As shown, the reverse osmosis unit 2 includes a primary reverse osmosis module 201 and a secondary reverse osmosis module 202; the raw water to be treated passes through the pretreatment unit 1, the primary reverse osmosis module 201, the secondary reverse osmosis module 202 and the resin unit 4 in sequence; the primary reverse osmosis module 201 is composed of a primary reverse osmosis membrane, and the secondary reverse osmosis module 202 is composed of a secondary reverse osmosis membrane;

[0048] The water inlet of the primary reverse osmosis module 201 is connected to the water outlet of the pretreatment unit 1, the first module water outlet of the reverse osmosis membrane modification unit 3, and the second module water outlet of the reverse osmosis membrane modification unit 3, respectively.

[0049] The water inlet of the secondary reverse osmosis module 202 is respectively connected to the water outlet of the primary reverse osmosis module 201, the first module water outlet of the reverse osmosis membrane modification unit 3, and the third module water outlet of the reverse osmosis membrane modification unit 3;

[0050] The water inlet of the primary reverse osmosis module 201 is connected to the modified reverse osmosis membrane regeneration unit 7;

[0051] The water outlets of the secondary reverse osmosis module 202 are respectively connected to the modified reverse osmosis membrane regeneration unit 7; the water outlets of the secondary reverse osmosis module 202 are connected to the resin unit 4;

[0052] The reverse osmosis unit 2 can be increased by multiple stages of reverse osmosis;

[0053] The material of the pipeline connected to the reverse osmosis membrane modification unit 3 is one of PVC-U, PE pipe and sanitary stainless steel.

[0054] The modified reverse osmosis membrane regeneration module includes a regeneration agent box and a regeneration agent dosing pump connected to the regeneration agent box; the regeneration agent box is connected to the water inlet of the primary reverse osmosis module 201 and the water outlet of the secondary reverse osmosis module 202. The regeneration agent is a NaOH solution, which enters the water inlet of the primary reverse osmosis module 201, exits from the primary concentrated water outlet, then enters the water inlet of the secondary reverse osmosis module 202, exits from the secondary concentrated water outlet, and finally returns to the regeneration agent box.

[0055] The early warning unit 6 includes a signal collection module, a data processing module and a signal output module; the signal collection module is used to collect or manually enter TOC detection data, the data processing module is used to process the signal collection module to obtain a processing result, and the signal output module is used to output the processing result of the signal processing module.

[0056] like Figure 2 As shown, a method for treating boiler feed water based on a modified reverse osmosis membrane comprises the following steps:

[0057] S1. Pretreatment: Pre-treat the raw water to remove suspended solid particles including colloids in the raw water to obtain pre-treated effluent;

[0058] S2. Primary reverse osmosis: The pretreated effluent is subjected to primary reverse osmosis treatment based on a modified reverse osmosis membrane to obtain primary reverse osmosis treated water;

[0059] S3. Secondary reverse osmosis: the primary reverse osmosis product water is subjected to secondary reverse osmosis treatment based on a second type modified reverse osmosis membrane to obtain reverse osmosis product water;

[0060] S4. Resin adsorption: The reverse osmosis water is treated with mixed bed resin to obtain desalinated water;

[0061] S5.TOC online analysis: Perform TOC online analysis on desalination water.

[0062] If (TOCt1-TOCt0) / TOCt0>25%, enter S6, otherwise the desalinated water enters the desalinated water tank, where t0 is the initial time of the system, t1 is the current time, TOCt0 is the TOC of the water at the initial time of the system, and TOCt1 is the TOC of the water at the current time;

[0063] S6. Regeneration treatment: regenerating the first type modified reverse osmosis membrane and the second type modified reverse osmosis membrane.

[0064] like Figure 3 As shown, in S2, a type of modified reverse osmosis membrane is obtained by modifying a type of reverse osmosis membrane, and the modification method comprises the following steps:

[0065] S21. The primary reverse osmosis membrane is positively flushed with clean water and produced water to flush away the residual protective liquid on the surface of the initial primary reverse osmosis membrane;

[0066] S22. The modified agent is used for a cyclic treatment of a primary reverse osmosis membrane. The produced water and the concentrated water are circulated in a modified agent water tank by a pump body, and the average produced water flux is controlled to be 25-50LMH;

[0067] S23. The primary reverse osmosis membrane is circulated using the modified agent 2. The produced water and the concentrated water are circulated in the modified agent 2 water tank controlled by the pump body, and the average produced water flux is controlled to be 25-50LMH.

[0068] like Figure 4 As shown, in S3, the second type modified reverse osmosis membrane is formed by modifying the second type reverse osmosis membrane, and the modification method comprises the following steps:

[0069] S31. The secondary reverse osmosis membrane is positively flushed with clean water and produced water to flush away the residual protective liquid on the surface of the initial secondary reverse osmosis membrane;

[0070] S32. The modified agent is used for a two-stage reverse osmosis membrane cycle treatment. The produced water and the concentrated water are controlled by the pump body to circulate in a modified agent water tank, and the average produced water flux is controlled to be 25-50LMH;

[0071] S33. Using modified agent three to carry out circulation treatment on the secondary reverse osmosis membrane, the produced water and concentrated water are controlled by the pump body to circulate in the modified agent three water tank, and the average produced water flux is controlled to be 25-50LMH.

[0072] The modifying agent is one or more of sulfobetaine, carboxybetaine, polyvinyl alcohol and alanine;

[0073] The second modifying agent is one or more of polyacrylic acid, anionic polyacrylamide, polystyrene sulfonic acid, maleic acid-acrylic acid copolymer, salicylic acid, and tannic acid;

[0074] The third modification agent is one or more of polyimide, polyethyleneimine, polyaniline, polylysine salicylic acid, and tannic acid.

[0075] like Figure 5 As shown, in S6, the regeneration process includes the following steps:

[0076] S61. The reverse osmosis membrane was modified by alkaline washing and soaking at pH 12, the water temperature was 25-35 degrees Celsius, the first cycle was rinsed for 0.5 hours, followed by a soaking time of 6-12 hours, and finally a cycle was rinsed for 0.5-1 hours;

[0077] S62. Performing first-class reverse osmosis membrane modification and second-class reverse osmosis membrane modification on the first-class reverse osmosis and the second-class reverse osmosis, respectively, to obtain regenerated first-class modified reverse osmosis membrane and second-class modified reverse osmosis membrane.

[0078] Example 1

[0079] In this embodiment, the primary reverse osmosis module 201 uses a 6-core pressure vessel arranged in a ratio of 4:2, and the secondary reverse osmosis module 202 uses a 6-core pressure vessel arranged in a ratio of 3:1. The primary reverse osmosis membrane and the secondary reverse osmosis membrane are modified respectively.

[0080] 1. Modify the primary reverse osmosis membrane. Perform positive flushing with clean water and produced water flushing with a water intake of 30 cubic meters per hour to flush away the residual protective liquid on the surface of the initial primary reverse osmosis membrane. Rinse continuously for 1 hour. Modified agent 1 uses 500ppm sulfobetaine to circulate the primary reverse osmosis membrane, and the produced water and concentrated water are circulated to the modified agent 1 water tank, and the average produced water flux is controlled to be 30LMH. Modified agent 2 uses 500ppm polyacrylic acid with a molecular weight of 3000 to circulate the primary reverse osmosis membrane, and the produced water and concentrated water are circulated to the modified agent 2 water tank, and the average produced water flux is controlled to be 30LMH.

[0081] 2. Modify the secondary reverse osmosis membrane. Perform positive flushing with clean water and produced water flushing with a water intake of 15 cubic meters per hour to flush away the residual protective liquid on the surface of the initial secondary reverse osmosis membrane, and flush continuously for 1 hour. Modification agent 1 uses 500ppm sulfobetaine to circulate the secondary reverse osmosis membrane, and the produced water and concentrated water are circulated to the modified agent 1 water tank, and the average produced water flux is controlled to be 30LMH. Modification agent 3 uses 500ppm polyethyleneimine with a molecular weight of 2500 to circulate the secondary reverse osmosis membrane, and the produced water and concentrated water are circulated to the modified agent 3 water tank, and the average produced water flux is controlled to be 30LMH.

[0082] The method provided by the present invention is used to treat boiler feed water. This embodiment provides the treatment method and effect of boiler feed water disclosed in the present invention. The raw water volume of boiler feed water is 50t / h, and the main water quality is shown in Table 1.

[0083] project Detection value TOC(mg / L) 23 Turbidity (NTU) 1.58 Total hardness (mg / L, in CaCO3) 43.5 pH 7.30

[0084] After pretreatment, primary reverse osmosis and secondary reverse osmosis, and resin adsorption treatment, the pretreatment includes coagulation clarification, multi-media filtration, and sand filtration. The treatment effect is shown in Table 2. The final effluent TOC content is less than 0.2 mg / L, meeting the effluent standard.

[0085]

[0086] It is to be understood that the present invention is described by some embodiments, and it is known to those skilled in the art that various changes or equivalent substitutions may be made to these features and embodiments without departing from the spirit and scope of the present invention. In addition, under the teachings of the present invention, these features and embodiments may be modified to adapt to specific circumstances and materials without departing from the spirit and scope of the present invention. Therefore, the present invention is not limited by the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this application are within the scope of protection of the present invention.

Claims

1. A boiler feed water treatment system based on modified reverse osmosis membrane, characterized in that: include A pretreatment unit (1) is connected to the reverse osmosis unit (2) and is used to pretreat the raw water to be treated; A reverse osmosis unit (2) is connected to the resin unit (4) and is used to perform reverse osmosis treatment on the raw water to be treated; The resin units (4) are respectively connected to the desalination water tanks and are used for mixed bed resin treatment of the reverse osmosis water; A TOC online detection unit (5) is used to perform TOC online analysis on the desalinated water; The early warning unit (6) is connected to the TOC online detection unit (5). A reverse osmosis membrane modification unit (3), connected to the reverse osmosis unit (2) and controlled by the early warning unit (6), for modifying the reverse osmosis membrane in the reverse osmosis unit (2); The modified reverse osmosis membrane regeneration unit (7) is connected to the reverse osmosis unit (2) and is controlled by the early warning unit (6) and is used for regenerating the modified reverse osmosis membrane in the reverse osmosis unit (2).

2. A boiler feed water treatment system based on a modified reverse osmosis membrane according to claim 1, characterized in that: The reverse osmosis membrane modification unit (3) comprises a first module, a second module, and a third module; the first module water outlet, the second module water outlet, and the third module water outlet are connected, and the water outlets are all provided with switching valves; The first module includes a first modified reagent tank and a first reagent dosing pump connected to the first modified reagent tank, the second module includes a second modified reagent tank and a second reagent dosing pump connected to the second modified reagent tank, and the third module includes a third modified reagent tank and a third reagent dosing pump connected to the third modified reagent tank.

3. A boiler feed water treatment system based on a modified reverse osmosis membrane according to claim 2, characterized in that: The reverse osmosis unit (2) comprises a primary reverse osmosis module (201) and a secondary reverse osmosis module (202); the primary reverse osmosis module (201) is composed of a primary reverse osmosis membrane, and the secondary reverse osmosis module (202) is composed of a secondary reverse osmosis membrane; The water inlet of the primary reverse osmosis module (201) is respectively connected to the water outlet of the pretreatment unit (1), the first module water outlet of the reverse osmosis membrane modification unit (3), and the second module water outlet of the reverse osmosis membrane modification unit (3). The water inlet of the secondary reverse osmosis module (202) is respectively connected to the water outlet of the primary reverse osmosis module (201), the first module water outlet of the reverse osmosis membrane modification unit (3), and the third module water outlet of the reverse osmosis membrane modification unit (3); The water inlet of the primary reverse osmosis module (201) is connected to the modified reverse osmosis membrane regeneration unit (7), and the water outlet of the secondary reverse osmosis module (202) is connected to the modified reverse osmosis membrane regeneration unit (7); The water outlet of the secondary reverse osmosis module (202) is connected to the resin unit (4).

4. A boiler feed water treatment system based on a modified reverse osmosis membrane according to claim 3, characterized in that: The modified reverse osmosis membrane regeneration module comprises a regeneration agent box and a regeneration agent dosing pump connected to the regeneration agent box; the regeneration agent box is connected to the water inlet of the primary reverse osmosis module (201) and the water outlet of the secondary reverse osmosis module (202).

5. The boiler feed water treatment system based on modified reverse osmosis membrane according to claim 1, characterized in that: The early warning unit (6) comprises a signal collection module, a data processing module and a signal output module; the signal collection module is used to collect or manually input TOC detection data, the data processing module is used to process the signal collection module to obtain a processing result, and the signal output module is used to output the processing result of the signal processing module.

6. A method for treating boiler feed water using a modified reverse osmosis membrane-based treatment system according to any one of claims 1 to 5, characterized in that: The following steps are involved: S1. Pretreatment: remove suspended solid particles including colloids in raw water to obtain pretreated effluent; S2. Primary reverse osmosis: The pretreated effluent is subjected to primary reverse osmosis treatment based on a modified reverse osmosis membrane to obtain primary reverse osmosis treated water; S3. Secondary reverse osmosis: The primary reverse osmosis product water is subjected to secondary reverse osmosis treatment based on a second type modified reverse osmosis membrane to obtain reverse osmosis product water; S4. Resin adsorption: The reverse osmosis water is treated with mixed bed resin to obtain desalinated water; S5.TOC online analysis: Perform TOC online analysis on the desalination water. If (TOCt1-TOCt0) / TOCt0>25%, enter S6, otherwise the desalination water enters the desalination water tank, where t0 is the initial time of the system, t1 is the current time, TOCt0 is the TOC of the water at the initial time of the system, and TOCt1 is the TOC of the water at the current time; S6. Regeneration treatment: regenerating the first type modified reverse osmosis membrane and the second type modified reverse osmosis membrane.

7. A method for treating boiler feed water based on a modified reverse osmosis membrane according to claim 6, characterized in that: In S2, a type of modified reverse osmosis membrane is obtained by modifying a type of reverse osmosis membrane, and the modification method comprises the following steps: S21. The primary reverse osmosis membrane is positively flushed with clean water and produced water to flush away the residual protective liquid on the surface of the initial primary reverse osmosis membrane; S22. The modified agent is used for a cyclic treatment of a primary reverse osmosis membrane. The produced water and the concentrated water are circulated in a modified agent water tank by a pump body, and the average produced water flux is controlled to be 25-50LMH; S23. The primary reverse osmosis membrane is circulated using the modified agent 2. The produced water and the concentrated water are circulated in the modified agent 2 water tank controlled by the pump body, and the average produced water flux is controlled to be 25-50LMH.

8. The method for treating boiler feed water based on a modified reverse osmosis membrane according to claim 7, characterized in that: In S3, the second type modified reverse osmosis membrane is obtained by modifying the second type reverse osmosis membrane, and the modification method comprises the following steps: S31. The secondary reverse osmosis membrane is positively flushed with clean water and produced water to flush away the residual protective liquid on the surface of the initial secondary reverse osmosis membrane; S32. The modified agent is used for a two-stage reverse osmosis membrane cycle treatment. The produced water and the concentrated water are circulated in a modified agent tank by a pump body, and the average produced water flux is controlled to be 25-50LMH; S33. Using modified agent three to carry out circulation treatment on the secondary reverse osmosis membrane, the produced water and concentrated water are controlled by the pump body to circulate in the modified agent three water tank, and the average produced water flux is controlled to be 25-50LMH.

9. The method for treating boiler feed water based on a modified reverse osmosis membrane according to claim 8, characterized in that: The modifying agent is one or more of sulfobetaine, carboxybetaine, polyvinyl alcohol and alanine; The second modifying agent is one or more of polyacrylic acid, anionic polyacrylamide, polystyrene sulfonic acid, maleic acid-acrylic acid copolymer, salicylic acid, and tannic acid; The third modification agent is one or more of polyimide, polyethyleneimine, polyaniline, polylysine salicylic acid, and tannic acid.

10. The method for treating boiler feed water based on a modified reverse osmosis membrane according to claim 6, characterized in that: In S6, the regeneration process comprises the following steps: S61. The reverse osmosis membrane was modified by alkaline washing and soaking at pH 12, the water temperature was 25-35 degrees Celsius, the first cycle was rinsed for 0.5 hours, followed by a soaking time of 6-12 hours, and finally a cycle was rinsed for 0.5-1 hours; S62. Performing first-class reverse osmosis membrane modification and second-class reverse osmosis membrane modification on the first-class reverse osmosis and the second-class reverse osmosis, respectively, to obtain regenerated first-class modified reverse osmosis membrane and second-class modified reverse osmosis membrane.

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