Full-quantitative resourceful treatment process and system for salt-containing water

Abstract

The invention provides a full-quantitative resourceful treatment process and system for salt-containing water. The process comprises the following steps: sequentially carrying out first softening treatment, filtering treatment and first RO treatment on to-be-treated salt-containing water to obtain concentrated water; sequentially carrying out second softening treatment, filtering treatment and salt separation treatment on the concentrated water to obtain monovalent salt liquid and divalent salt liquid; sequentially performing filtration treatment, third RO treatment and salt crystallization treatment on the monovalent salt liquid to obtain monovalent salt; sequentially carrying out filtering treatment, second RO treatment and salt crystallization treatment on the divalent salt liquid to obtain divalent salt; drying the mother liquor after the monovalent salt crystallization treatment and the divalent salt crystallization treatment to obtain mixed salt, sequentially carrying out drying treatment, heat treatment and crushing treatment on the obtained mixed salt, adding the crushed mixed salt into the concentrated water after the first RO treatment for dissolving, and carrying out circulating treatment; the salt resources in the mine water are effectively recycled, and the pollution of organic matters to the environment is reduced.

Description

Technical Field

[0001] The present invention belongs to the technical field of salt water treatment, and specifically relates to a fully quantitative resource treatment process and system for salt water. Background Art

[0002] While the development of the chemical industry has brought huge benefits to mankind, it also poses a potential huge environmental risk. The production of chemicals such as non-ferrous metal smelting, power battery production and recycling, coal chemical industry, and chemical raw material synthesis will produce a large amount of industrial by-product high-salt water. During industrial water treatment, the acid and alkali reagents added to the industrial wastewater to be treated will eventually be converted into salt, and then industrial water treatment will also produce industrial by-product high-salt water. When these industrial by-product high-salt waters are conventionally treated, the industrial by-product high-salt water is generally concentrated and crystallized. While obtaining industrial by-product salts, miscellaneous salts with a total salt content of about 10% will also be produced. In terms of environmental supervision, these miscellaneous salts are usually classified as hazardous wastes, and companies usually need to pay high fees to treat these miscellaneous salts, which seriously reduces the profitability of the company.

[0003] my country is rich in coal resources, and coal mining is often accompanied by the generation of a large amount of mine water. Every ton of coal mined produces about 2 tons of mine water. In 2022, my country's raw coal output was 4.56 billion tons, and the amount of mine water generated in my country in 2022 was about 9.12 billion tons. Since 2013, the country has successively introduced a series of policies to promote the development and utilization of mine water resources. However, a large amount of mixed salts are generated in the process of mine water development and utilization. There is no way to utilize these mixed salts as resources. In this context, how to effectively recover salt resources in mine water and reduce the pollution of organic matter to the environment has become an urgent problem for mining companies. At the same time, sodium chloride and sodium sulfate, as basic chemical raw materials, have a wide market demand in many industries such as chemical, glass, and papermaking. At present, in the process of sodium chloride and sodium sulfate, the recycled wastewater is not further treated, resulting in a large amount of salt substances in the recycled wastewater, which is directly discarded and causes serious pollution to the environment. Summary of the invention

[0004] In order to solve the problem of mixed salts generated in the existing saline wastewater treatment technology, the present invention provides a fully quantitative resource treatment process and method for salt water containing water that further treats the crystallization mother liquor during the treatment of saline wastewater. In the process, the crystallization mother liquor is dried to obtain mixed salts, which are further dried and heat-treated to eliminate COD and then redissolved, and then the corresponding single salt products are obtained by salt separation, thereby eliminating the generation of mixed salts during the treatment of salt water containing water and avoiding the potential pollution of the environment by mixed salts.

[0005] In order to achieve the above object, the present invention provides the following technical solution: a fully quantitative resource treatment process of salt water, comprising:

[0006] The salt water to be treated is subjected to a first softening treatment, a filtration treatment and a first RO treatment in sequence to obtain concentrated water and fresh water;

[0007] The concentrated water obtained by the first RO treatment is subjected to a second softening treatment, a filtration treatment and a salt separation treatment in sequence to obtain a monovalent salt liquid and a divalent salt liquid;

[0008] The monovalent salt liquid obtained by the salt separation treatment is subjected to filtering treatment, third RO treatment and salt crystallization treatment in sequence to obtain monovalent salt and monovalent salt crystal mother liquor;

[0009] The divalent salt liquid obtained by the salt separation treatment is subjected to filtering treatment, second RO treatment and salt crystallization treatment in sequence to obtain divalent salt and divalent salt crystal mother liquor;

[0010] The monovalent salt crystallization mother liquor and the divalent salt crystallization mother liquor are concentrated and dried to obtain a mixed salt, which is sequentially dried, heat treated and crushed, and then added to the concentrated water obtained from the first RO treatment to be dissolved and circulated.

[0011] Preferably, the crushed mixed salt is added to the concentrated water obtained by the first RO to be fully dissolved, and the second softening treatment is performed after the mixed salt is fully dissolved in the concentrated water.

[0012] Preferably, tail gas treatment is performed on the tail gas generated when the mixed salt is subjected to heat treatment.

[0013] Preferably, the fresh water obtained by the third RO treatment of the monovalent salt liquid and the fresh water obtained by the second RO treatment of the divalent salt liquid are stored together.

[0014] Preferably, the salt separation treatment method is a nanofiltration membrane salt separation method, the liquid passing through the nanofiltration membrane is a monovalent salt liquid, and the liquid retained by the nanofiltration membrane is a divalent salt liquid.

[0015] Preferably, the mixed salt is heat treated by pyrolysis, wherein the pyrolysis temperature is 450-600°C, the residence time is 1-30 minutes, and the pyrolysis atmosphere includes nitrogen (95%-30%), air, and water vapor.

[0016] A fully quantitative resource processing system for salt water, comprising a primary fresh water recovery unit, a salt separation unit, a monovalent concentration crystallization unit, a divalent concentration crystallization unit and a mixed salt processing unit;

[0017] The concentrated water obtained after the salt water to be treated is recovered by the primary fresh water recovery unit enters the salt separation unit for salt separation treatment, the monovalent salt liquid after the treatment in the salt separation unit enters the monovalent concentration crystallization unit for crystallization to obtain a monovalent salt product, and the divalent salt liquid enters the divalent concentration crystallization unit for crystallization to obtain a divalent salt product; the mother liquor obtained from the monovalent concentration crystallization unit and the divalent concentration crystallization unit is subjected to mother liquor drying / spray drying to obtain mixed salt, the mixed salt enters the mixed salt treatment unit for treatment, and the treated mixed salt is dissolved in the concentrated water obtained by the primary fresh water recovery unit and then re-enters the salt separation unit.

[0018] Preferably, the primary fresh water recovery unit includes a first softening device, a first security filter device, a first RO device, a first water production storage device and a concentrated water storage device; the water inlet of the first softening device is connected to the salt water pipeline to be treated, the water outlet of the first softening device is connected to the water inlet of the first security filter device, the water outlet of the first security filter device is connected to the water inlet of the first RO device, the concentrated water outlet of the first RO device is connected to the concentrated water storage device, the fresh water outlet of the first RO device is connected to the first water production storage device, and the concentrated water storage device is connected to the salt separation unit.

[0019] Preferably, the salt separation unit comprises a mixed salt dissolving device, a second softening device, a second safety filtering device, a salt separation device, a monovalent salt water phase storage device and a divalent salt water phase storage device; the water inlet of the mixed salt dissolving device is connected to the water outlet of the concentrated water storage device, and the mixed salt dissolving device receives the crushed mixed salt; the water outlet of the mixed salt dissolving device is connected to the water inlet of the second softening device, the water outlet of the second softening device is connected to the water inlet of the second safety filtering device, the water outlet of the second safety filtering device is connected to the water inlet of the salt separation device, the monovalent salt water phase outlet of the salt separation device is connected to the water inlet of the monovalent salt water phase storage device, and the divalent salt water phase outlet is connected to the water inlet of the divalent salt water phase storage device;

[0020] The monovalent concentrated crystallization unit includes a fourth security filter device, a third RO device, a monovalent salt crystallization device and a monovalent salt product storage device; the water outlet of the monovalent salt water phase storage device is connected to the water inlet of the fourth security filter device, the water outlet of the fourth security filter device is connected to the water inlet of the third RO device, the concentrated water outlet of the third RO device is connected to the water inlet of the monovalent salt crystallization device, and the product crystallized by the monovalent salt crystallization device enters the monovalent salt product storage device for storage;

[0021] The divalent salt concentration crystallization unit includes a third security filter device, a second RO device, a divalent salt crystallization device and a divalent salt product storage device; the water outlet of the divalent salt water phase storage device is connected to the water inlet of the third security filter device, the water outlet of the third security filter device is connected to the water inlet of the second RO device, the concentrated water outlet of the second RO device is connected to the divalent salt crystallization device, and the product crystallized by the divalent salt crystallization device enters the divalent salt product storage device for storage;

[0022] Fresh water outlets of the third RO device and the second RO device are both connected to the second produced water storage device;

[0023] The water outlets of the monovalent salt crystallization device and the divalent salt crystallization device are connected to the mixed salt treatment unit.

[0024] Preferably, the mixed salt treatment unit includes a crystallization mother liquor storage device, a mixed salt drying device, a mixed salt drying device, a mixed salt heat treatment device, an exhaust gas treatment device, and a mixed salt crushing device; the water outlet of the crystallization mother liquor storage device is connected to the water inlet of the mixed salt drying device, the solid phase mixed salt obtained by the mixed salt drying device is dehydrated by the mixed salt drying device to obtain dehydrated mixed salt, the dehydrated mixed salt is treated by the mixed salt heat treatment device to obtain heat-treated mixed salt and heat-treated gas, the gas outlet of the mixed salt heat treatment device is connected to the exhaust gas treatment device, the heat-treated mixed salt outlet of the mixed salt heat treatment device is connected to the mixed salt crushing device, and the crushed mixed salt enters the mixed salt dissolution device.

[0025] The fully quantitative resource treatment process of salt water provided by the present invention has the following beneficial effects:

[0026] The treatment process provided by the present invention can fully recycle water resources in salt water, avoid wasting water resources, and at the same time, after heat treatment, the generated mixed salt enters the salt separation treatment unit for circulation treatment during water treatment, ensuring that the generated mixed salt is not discharged to the outside, eliminating the cost of separately reprocessing the generated mixed salt in the later stage, reducing the treatment cost, and at the same time, due to the circulation treatment of the mixed salt, it has a protective effect on the environment, and the obtained monovalent salt (sodium chloride) and divalent salt (sodium sulfate) meet the recycling standards, thereby increasing economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the embodiment of the present invention and its design scheme, the following briefly introduces the drawings required for this embodiment. The drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0028] Figure 1 This is a flow chart of the fully quantitative resource processing method of salt water in the present invention;

[0029] Figure 2 It is a block diagram of the fully quantitative resource processing system of salt water in the present invention. DETAILED DESCRIPTION

[0030] In order to enable those skilled in the art to better understand the technical solution of the present invention and implement it, the present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and cannot be used to limit the scope of protection of the present invention.

[0031] like Figure 1 The embodiment shown provides a fully quantitative resource processing process for salt water, including:

[0032] The salt water is first subjected to a first softening treatment, and the softened salt water is subjected to a first security filtration treatment, and the salt water subjected to the first security filtration treatment is subjected to a first RO treatment to obtain fresh water and concentrated water, and the fresh water and concentrated water subjected to the first RO treatment are stored respectively;

[0033] The concentrated water stored after the first RO treatment is subjected to a second softening treatment, and the concentrated water after the second softening treatment is subjected to a second security filtration. The liquid after the second security filtration is subjected to a salt separation treatment. The salt separation treatment method adopted in this embodiment is a nanofiltration membrane salt separation method. When the salt separation treatment is performed, the liquid enters the nanofiltration membrane salt separation device after the second security filtration. The liquid passing through the nanofiltration membrane is a monovalent salt liquid, and the liquid retained by the nanofiltration membrane is a divalent salt liquid.

[0034] The monovalent salt liquid phase and the divalent salt liquid phase produced after the salt separation treatment are stored separately to complete the salt separation treatment. In this embodiment, the monovalent salt water phase after the salt separation treatment is sodium chloride liquid, and the divalent salt water phase is sodium sulfate liquid.

[0035] After the separation of monovalent salt and divalent salt is completed, the stored monovalent salt liquid is subjected to the fourth security filtration and the third RO treatment, and the divalent salt liquid is subjected to the third security filtration and the second RO treatment. The monovalent salt liquid and the divalent salt liquid are uniformly stored after the RO treatment of the produced water, and the treated liquids are respectively subjected to salt crystallization treatment to obtain monovalent salt products and divalent salt products; the method used for the crystallization treatment in this embodiment can be a natural evaporation crystallization method or a heating evaporation crystallization method, and the mother liquor after crystallization is stored to complete the crystallization of monovalent salt and the crystallization treatment of divalent salt. At this time, the monovalent salt product and the divalent salt product in the salt water are effectively separated, and the effective recovery of salt resources in the salt water is achieved, and the salt water is prevented from causing environmental pollution. However, the crystallization mother liquor generated at this time still contains a considerable amount of salts (potassium salts, ammonium salts, magnesium salts, sodium salts, calcium salts, etc.) and organic matter has not been fully extracted, and direct discharge will still cause serious pollution to the environment. In view of this, the crystallization mother liquor after crystallization in this embodiment needs to be further treated.

[0036] The mother liquor is dried to obtain mixed salt. The drying method in this embodiment can be spray drying, etc. The obtained mixed salt is dried, heat treated and crushed in sequence, and then added to the concentrated water after the first RO treatment for dissolution and then recycled to avoid discharging the mixed salt into the environment. At the same time, during the heat treatment process, the pollutants contained in the generated tail gas (such as nitrogen dioxide, ammonia, etc.) are treated to avoid air pollution.

[0037] All softening treatments, security filtration treatments and RO treatments in this embodiment are carried out by conventional means in the technical field, and the specific methods are not described in detail. When the mixed salt is dried, one of the conventional drum drying or fluidized drying in the technical field is adopted. When the mixed salt is heat treated, the COD contained in the mixed salt is decomposed into gas and coke, and the gas is discharged after being treated by the tail gas treatment device to meet the standards. The coke can be mined as slag when the mixed salt is dissolved. The heat treatment method adopted in this embodiment is pyrolysis. When pyrolysis is carried out, the pyrolysis temperature is 450-600°C, the residence time is 1-30min, and the pyrolysis atmosphere includes a mixture of one or more of the following atmospheres: nitrogen atmosphere, air atmosphere, and water vapor atmosphere. When only nitrogen atmosphere is used, nitrogen can be obtained by an air separation system, and the nitrogen content can be 30%-95%.

[0038] In one embodiment, Figure 2 The invention provides a fully quantitative resource processing system for salt water, including a primary fresh water recovery unit, a salt separation unit, a monovalent concentration crystallization unit, a divalent concentration crystallization unit and a mixed salt processing unit;

[0039] The primary fresh water recovery unit comprises a first softening device 1, a first security filter device 2, a first RO device 3, a concentrated water storage device 4 and a first produced water storage device 5; the water inlet of the first softening device 1 is connected to the salt water pipeline to be treated, the water outlet of the first softening device 1 is connected to the water inlet of the first security filter device 2, the water outlet of the first security filter device 2 is connected to the water inlet of the first RO device 3, the concentrated water outlet of the first RO device 3 is connected to the water inlet of the concentrated water storage device 4, and the produced water outlet of the first RO device 3 is connected to the water inlet of the concentrated water storage device 4. It is connected with the water inlet of the first produced water storage device 5, and the water outlet of the concentrated water storage device 4 is connected with the water inlet of the salt separation unit. Specifically, during operation, the salt water enters the first softening device 1 through the pipeline for softening treatment, the salt water after softening treatment enters the first security filter device 2 for filtration treatment, the filtered salt water enters the first RO device 3 for reverse osmosis treatment, and the first produced water (fresh water) obtained enters the first produced water storage device 5 for storage, and the treated concentrated water is stored through the concentrated water storage device 4.

[0040] The salt separation unit comprises a mixed salt dissolving device 6, a second softening device 7, a second security filtering device 8, a salt separation device 9, a monovalent salt water phase storage device 10 and a divalent salt water phase storage device 11; the water inlet of the mixed salt dissolving device 6 is respectively connected with the water outlet of the concentrated water storage device 4, and the mixed salt crushed by the mixed salt processing unit enters into the mixed salt dissolving device 6, the water outlet of the mixed salt dissolving device 6 is connected with the water inlet of the second softening device 7, the water outlet of the second softening device 7 is connected with the water inlet of the second security filtering device 8, the water outlet of the second security filtering device 8 is connected with the water inlet of the salt separation device 9, the monovalent salt water phase outlet of the salt separation device 9 is connected with the water inlet of the monovalent salt water phase storage device 10, and the divalent salt water phase outlet is connected with the water inlet of the divalent salt water phase storage device 11; specifically, during the salt separation process, the salt water entering into the mixed salt dissolving device 6 is connected to the water outlet of the second softening device 7. The concentrated water and the mixed salt are fully dissolved, wherein the concentrated water comes from the concentrated water stored in the concentrated water storage device 4, and the mixed salt comes from the mixed salt treatment unit; after being fully dissolved, it enters the second softening device 7 for softening treatment, and the liquid after softening treatment is filtered through the second security filter device 8 to remove insoluble impurities in the liquid to protect the nanofiltration membrane, such as coke mixed in the mixed salt, and the filtered liquid enters the salt separation device 9 for salt separation treatment. The salt separation device used in this embodiment is a nanofiltration membrane salt separation device. When the liquid entering the nanofiltration membrane salt separation device is salted, the liquid that passes through the nanofiltration membrane is a monovalent salt liquid, and the liquid retained by the nanofiltration membrane is a divalent salt liquid. The monovalent salt liquid is stored in the monovalent salt water phase storage device 10, and the divalent salt liquid is stored in the divalent salt water phase storage device 11, in preparation for the crystallization of the monovalent salt and the divalent salt.

[0041] The monovalent salt concentration crystallization unit includes a fourth security filter device 12, a third RO device 13, a monovalent salt crystallization device 14 and a monovalent salt product storage device 15; the water outlet of the monovalent salt water phase storage device 10 is connected to the water inlet 12 of the fourth security filter device, the water outlet of the fourth security filter device 12 is connected to the water inlet of the third RO device 13, the concentrated water outlet of the third RO device 13 is connected to the water inlet of the monovalent salt crystallization device 14, and the product crystallized by the monovalent salt crystallization device 14 enters the monovalent salt product storage device 15 for storage;

[0042] Before the monovalent salt is crystallized, the monovalent salt liquid is subjected to security filtration through the fourth security filter device 12 to ensure the normal operation of the third RO device 13. The monovalent salt liquid that has passed through the fourth security filter device 12 enters the third RO device 13 for reverse osmosis treatment. When the monovalent salt liquid is subjected to reverse osmosis treatment through the third RO device 13, the reverse osmosis concentrated water enters the monovalent salt crystallization device 14 for monovalent salt crystallization treatment, and the reverse osmosis produced water enters the second produced water storage device 20 for storage and reuse; the monovalent salt product after crystallization treatment is stored through the monovalent salt product storage device 15, and the crystallization mother liquor enters the crystallization mother liquor storage device 21 for storage.

[0043] The divalent salt concentration crystallization unit includes a third security filter device 16, a second RO device 17, a divalent salt crystallization device 18 and a divalent salt product storage device 19; the water outlet of the divalent salt water phase storage device 11 is connected to the water inlet of the third security filter device 16, the water outlet of the third security filter device 16 is connected to the water inlet of the second RO device 17, the concentrated water outlet of the second RO device 17 is connected to the water inlet of the divalent salt crystallization device 18, and the product crystallized by the divalent salt crystallization device 18 enters the divalent salt product storage device 19 for storage;

[0044] When the divalent salt is crystallizing, the divalent salt liquid is security filtered through the third security filter device 16 to ensure the normal operation of the second RO device 17. The filtered divalent salt liquid enters the second RO device 17 for reverse osmosis treatment. After reverse osmosis treatment, the reverse osmosis concentrated water enters the divalent salt crystallization device 18 for divalent salt crystallization treatment. The reverse osmosis produced water enters the second produced water storage device 20 for storage. The divalent salt product after crystallization treatment is stored in the divalent salt product storage device 19, and the crystallization mother liquor enters the crystallization mother liquor storage device 21 for storage.

[0045] The mixed salt treatment unit includes a crystallization mother liquid storage device 21, a mixed salt drying device 22, a mixed salt drying device 23, a mixed salt heat treatment device 24, a tail gas treatment device 25, and a mixed salt crushing device 26; the water outlet of the crystallization mother liquid storage device 21 is connected to the water inlet of the mixed salt drying device 22, the solid phase mixed salt obtained by the mixed salt drying device 22 is dehydrated by the mixed salt drying device 23 to obtain dehydrated mixed salt, the dehydrated mixed salt is treated by the mixed salt heat treatment device 24 to obtain heat-treated mixed salt and heat-treated gas, the gas outlet of the mixed salt heat treatment device 24 is connected to the tail gas treatment device 25, the heat-treated mixed salt outlet of the mixed salt heat treatment device 24 is connected to the mixed salt crushing device 26, and the crushed mixed salt enters the mixed salt dissolving device 6.

[0046] The mother liquor in the crystallization mother liquor storage device 21 enters the mixed salt drying device 22 for drying treatment to obtain a solid phase mixed salt. At this time, the obtained mixed salt is further placed in the mixed salt drying device 23 for drying treatment to further reduce the moisture content of the mixed salt. The dried mixed salt is placed in the mixed salt heat treatment device 24 for heat treatment. The heat treatment device used in this embodiment is a pyrolysis heat treatment device. When the pyrolysis is performed, the pyrolysis temperature of the pyrolysis heat treatment device is 450-600°C, the residence time is 1-30min, and the pyrolysis atmosphere includes nitrogen, air, and water vapor. When the mixed salt is pyrolyzed, the gas generated by the pyrolysis enters the tail gas treatment device 25 for tail gas treatment. After the tail gas is treated, it meets the emission standards, thereby avoiding air pollution caused by the gas generated by the pyrolysis. The mixed salt after pyrolysis enters the mixed salt crushing device 26 for crushing treatment, and then the crushed mixed salt is added to the mixed salt dissolving device 6 for dissolution and repeated recycling.

[0047] The treatment process provided in this embodiment can fully recycle the water resources in the salt water, avoid wasting water resources, and at the same time, after heat treatment, the mixed salt generated during water treatment enters the salt separation treatment unit for circulation treatment, ensuring that the generated mixed salt is not discharged to the outside, eliminating the cost of reprocessing the generated mixed salt separately at a later time, reducing the treatment cost, and at the same time, due to the circulation treatment of the mixed salt, it has a protective effect on the environment, and the obtained monovalent salt (sodium chloride) and divalent salt (sodium sulfate) meet the recycling standards, thereby increasing economic benefits.

[0048] It should be noted that the above specific implementation methods can enable those skilled in the art to more fully understand the invention, but do not limit the invention in any way. Therefore, although the present specification and embodiments have described the invention in detail, those skilled in the art should understand that the invention can still be modified or replaced by equivalents; and all technical solutions and improvements that do not deviate from the spirit and scope of the invention are included in the protection scope of the patent for the invention. Any figure mark in the claims should not be regarded as limiting the claims involved.

Claims

1. A fully quantitative resource treatment process for salt water, characterized in that: include: The salt water to be treated is subjected to a first softening treatment, a filtration treatment and a first RO treatment in sequence to obtain concentrated water and fresh water; The concentrated water obtained by the first RO treatment is subjected to a second softening treatment, a filtration treatment and a salt separation treatment in sequence to obtain a monovalent salt liquid and a divalent salt liquid; The monovalent salt liquid obtained by the salt separation treatment is subjected to filtering treatment, third RO treatment and salt crystallization treatment in sequence to obtain monovalent salt and monovalent salt crystal mother liquor; The divalent salt liquid obtained by the salt separation treatment is subjected to filtering treatment, second RO treatment and salt crystallization treatment in sequence to obtain divalent salt and divalent salt crystal mother liquor; The monovalent salt crystallization mother liquor and the divalent salt crystallization mother liquor are concentrated and dried to obtain a mixed salt, which is sequentially dried, heat treated and crushed, and then added to the concentrated water obtained from the first RO treatment to be dissolved and circulated.

2. The fully quantitative resource treatment process of salt water according to claim 1 is characterized in that: The crushed mixed salt is added to the concentrated water obtained from the first RO treatment to be fully dissolved before the second softening treatment.

3. The fully quantitative resource treatment process of salt water according to claim 1 is characterized in that: The tail gas generated when the mixed salt is subjected to heat treatment is subjected to tail gas treatment.

4. The fully quantitative resource treatment process of salt water according to claim 2 is characterized in that: The salt separation treatment method is the nanofiltration membrane salt separation method. The liquid passing through the nanofiltration membrane is a monovalent salt liquid, and the liquid retained by the nanofiltration membrane is a divalent salt liquid.

5. The fully quantitative resource treatment process of salt water according to claim 1 is characterized in that: The fresh water obtained by treating the monovalent salt liquid through the third RO and the fresh water obtained by treating the divalent salt liquid through the second RO are stored together.

6. The fully quantitative resource treatment process of salt water according to claim 1 is characterized in that: The method for heat treatment of the mixed salt is pyrolysis, wherein the pyrolysis temperature is 450-600°C, the residence time is 1-30 minutes, and the pyrolysis atmosphere includes nitrogen, air, and water vapor.

7. A fully quantitative resource processing system for salt water, characterized in that: Including, primary fresh water recovery unit, salt separation unit, monovalent concentration crystallization unit, divalent concentration crystallization unit and mixed salt treatment unit; The concentrated water obtained after the salt water to be treated is recovered by the primary fresh water recovery unit enters the salt separation unit for salt separation treatment, the monovalent salt liquid after the treatment in the salt separation unit enters the monovalent concentration crystallization unit for crystallization to obtain a monovalent salt product, and the divalent salt liquid enters the divalent concentration crystallization unit for crystallization to obtain a divalent salt product; the mother liquor obtained from the monovalent concentration crystallization unit and the divalent concentration crystallization unit is subjected to mother liquor drying / spray drying to obtain mixed salt, the mixed salt enters the mixed salt treatment unit for treatment, and the treated mixed salt is dissolved in the concentrated water obtained by the primary fresh water recovery unit and then re-enters the salt separation unit.

8. A fully quantitative resource processing system for salt water according to claim 7, characterized in that: The primary fresh water recovery unit includes a first softening device, a first security filter device, a first RO device, a first water production storage device and a concentrated water storage device; the water inlet of the first softening device is connected to the salt water pipeline to be treated, the water outlet of the first softening device is connected to the water inlet of the first security filter device, the water outlet of the first security filter device is connected to the water inlet of the first RO device, the concentrated water outlet of the first RO device is connected to the concentrated water storage device, the fresh water outlet of the first RO device is connected to the first water production storage device, and the concentrated water storage device is connected to the salt separation unit.

9. A fully quantitative resource processing system for salt water according to claim 8, characterized in that: The salt separation unit includes a mixed salt dissolving device, a second softening device, a second safety filtering device, a salt separation device, a monovalent salt water phase storage device and a divalent salt water phase storage device; the water inlet of the mixed salt dissolving device is connected to the water outlet of the concentrated water storage device, and the mixed salt dissolving device receives the crushed mixed salt, the water outlet of the mixed salt dissolving device is connected to the water inlet of the second softening device, the water outlet of the second softening device is connected to the water inlet of the second safety filtering device, the water outlet of the second safety filtering device is connected to the water inlet of the salt separation device, the monovalent salt water phase outlet of the salt separation device is connected to the water inlet of the monovalent salt water phase storage device, and the divalent salt water phase outlet is connected to the water inlet of the divalent salt water phase storage device; The monovalent concentrated crystallization unit includes a fourth security filter device, a third RO device, a monovalent salt crystallization device and a monovalent salt product storage device; the water outlet of the monovalent salt water phase storage device is connected to the water inlet of the fourth security filter device, the water outlet of the fourth security filter device is connected to the water inlet of the third RO device, the concentrated water outlet of the third RO device is connected to the water inlet of the monovalent salt crystallization device, and the product crystallized by the monovalent salt crystallization device enters the monovalent salt product storage device for storage; The divalent salt concentration crystallization unit includes a third security filter device, a second RO device, a divalent salt crystallization device and a divalent salt product storage device; the water outlet of the divalent salt water phase storage device is connected to the water inlet of the third security filter device, the water outlet of the third security filter device is connected to the water inlet of the second RO device, the concentrated water outlet of the second RO device is connected to the divalent salt crystallization device, and the product crystallized by the divalent salt crystallization device enters the divalent salt product storage device for storage; Fresh water outlets of the third RO device and the second RO device are both connected to the second produced water storage device; The water outlets of the monovalent salt crystallization device and the divalent salt crystallization device are connected to the mixed salt treatment unit.

10. A fully quantitative resource processing system for salt water according to claim 9, characterized in that: The mixed salt treatment unit includes a crystallization mother liquor storage device, a mixed salt drying device, a mixed salt drying device, a mixed salt heat treatment device, an exhaust gas treatment device, and a mixed salt crushing device; the water outlet of the crystallization mother liquor storage device is connected with the water inlet of the mixed salt drying device, the solid phase mixed salt obtained by the mixed salt drying device is dehydrated by the mixed salt drying device to obtain dehydrated mixed salt, the dehydrated mixed salt is treated by the mixed salt heat treatment device to obtain heat-treated mixed salt and heat-treated gas, the gas outlet of the mixed salt heat treatment device is connected with the exhaust gas treatment device, the heat-treated mixed salt outlet of the mixed salt heat treatment device is connected with the mixed salt crushing device, and the crushed mixed salt enters the mixed salt dissolution device.

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