Resourceful treatment system for waste incineration fly ash

Abstract

According to the waste incineration fly ash resourceful treatment system, a pretreatment unit decomposes dioxin in fly ash, and dissoluble ions in the fly ash are separated through water washing; the water washing liquid detoxification unit captures heavy metal ions in the fly ash water washing liquid treated by the pretreatment unit; the softening unit is used for removing calcium ions in the fly ash water washing liquid treated by the water washing liquid detoxification unit; the selective electrodialysis unit is used for separating monovalent salt ions and divalent salt ions in the fly ash washing liquid treated by the softening unit; and the salt manufacturing unit is used for evaporating and crystallizing the monovalent salt ions separated by the selective electrodialysis unit to manufacture salt. The device solves the problems of dioxin pollution, excessive heavy metal and low purity of salt produced by fly ash resourceful treatment in fly ash resourceful treatment.

Description

TECHNICAL FIELD

[0001] The utility model relates to a kind of garbage incineration fly ash resource processing system, belong to fly ash processing technical field. BACKGROUND

[0002] Fly ash is solid waste generated in the process of waste incineration, and mainly contains a large amount of calcium and chlorine. Calcium exists in the form of compounds such as CaO and CaCO3, accounting for 20-35% of the total mass of fly ash. Chlorine exists in the form of KCl and NaCl, accounting for up to 15-20% of the total mass of fly ash. In addition, fly ash also contains heavy metals such as Cr and Ni, as well as toxic substances such as dioxins. Improper handling can harm the ecological environment and personal health.

[0003] In the prior art, the fly ash disposal scheme includes cement solidification, cement kiln co-processing, and sintering solidification. Fly ash needs to be landfilled after cement solidification, but landfilling will occupy a large amount of land resources. Unremoved dioxins, heavy metals, and salts will enter the environment with leachate, causing soil and groundwater pollution and posing a long-term potential threat to the environment. Fly ash is also commonly used to make cement or building materials through cement kiln co-processing, but a large amount of chloride ions in fly ash will affect the quality of cement. Water washing pretreatment is the main method for removing dissolved ions in fly ash. Chloride salts in fly ash water washing liquid can be reused through evaporation crystallization, but sulfate in fly ash will affect the quality of the finished salt. Therefore, new fly ash resource processing schemes are urgently needed to address the problems of excessive heavy metal content, dioxin pollution, and low salt purity in the fly ash resource processing process. SUMMARY

[0004] The utility model provides a kind of garbage incineration fly ash resource processing system to solve the problems of dioxin pollution, excessive heavy metal content and low salt purity in fly ash resource processing, in view of the deficiencies of prior art.

[0005] The technical solution of the utility model to solve the above technical problem is as follows: a kind of garbage incineration fly ash resource processing system, including pretreatment unit, water washing liquid detoxification unit, softening unit, selective electrodialysis unit and salt making unit;

[0006] The pretreatment unit is connected to the water washing liquid detoxification unit by a conveying pipeline. The pretreatment unit is used to decompose dioxins in fly ash and separate dissolved ions in fly ash using countercurrent water washing. The water washing liquid detoxification unit is used to fix heavy metal ions in fly ash water washing liquid delivered by the pretreatment unit.

[0007] The water washing liquid detoxification unit is connected to the softening unit through a delivery pipeline, and the softening unit is used to remove calcium ions in the fly ash water washing liquid treated by the water washing liquid detoxification unit;

[0008] The softening unit is connected to the selective electrodialysis unit through a delivery pipeline, and the selective electrodialysis unit is used to separate the monovalent salt ions and divalent salt ions in the fly ash water washing liquid treated by the softening unit;

[0009] The selective electrodialysis unit is connected to the salt-making unit through a delivery pipeline, and the salt-making unit is used to evaporate and crystallize the monovalent salt ions separated by the selective electrodialysis unit to make salt.

[0010] As a preferred solution for the waste incineration fly ash resource processing system, the pretreatment unit includes a low-temperature pyrolysis device, a countercurrent water washing device and a filter press device; the low-temperature pyrolysis device is used to degrade dioxins in the fly ash by oxygen isolation and cool the decomposed fly ash; the countercurrent water washing device is used to remove soluble ions in the fly ash; and the filter press device is used to separate the washed fly ash and the washing liquid.

[0011] As a preferred solution for the waste incineration fly ash resource processing system, the water washing liquid detoxification unit includes a water washing liquid detoxification reaction pool, and the water washing liquid detoxification reaction pool and the pretreatment unit are connected by a conveying pipeline. The water washing liquid detoxification unit captures heavy metal ions in the fly ash water washing liquid treated by the pretreatment unit through the water washing liquid detoxification reaction pool.

[0012] As a preferred solution of the waste incineration fly ash resource treatment system, the softening unit includes a calcium sulfate crystallizer and a softening reaction tank, the calcium sulfate crystallizer is connected to the water wash liquid detoxification reaction tank through a delivery pipeline, and the softening reaction tank is connected to the calcium sulfate crystallizer through a delivery pipeline;

[0013] The selective electrodialysis unit comprises a selective electrodialysis device, the selective electrodialysis device and the softening reaction tank are connected via a delivery pipeline, and the concentrated water side of the selective electrodialysis device is connected to the calcium sulfate crystallizer via a delivery pipeline;

[0014] The calcium sulfate crystallizer is used to react the calcium in the fly ash water washing liquid with the sulfate radicals on the divalent ion concentrated water side of the selective electrodialysis device to crystallize calcium sulfate; the softening reaction tank is used to remove the remaining calcium ions in the fly ash water washing liquid through a sodium carbonate solution, and the softening reaction tank is also used to adjust the pH value of the fly ash water washing liquid.

[0015] As a preferred solution for the waste incineration fly ash resource treatment system, the selective electrodialysis device includes a monovalent selective anion exchange membrane and an anion and cation exchange membrane;

[0016] The fresh water side of the selective electrodialysis device is connected to the pretreatment unit for reuse via a delivery pipeline.

[0017] As a preferred solution for the waste incineration fly ash resource processing system, the salt-making unit includes an evaporation crystallizer, which is connected to the monovalent ion concentrated water side of the selective electrodialysis device through a conveying pipeline. The evaporation crystallizer is used to adjust the evaporation temperature and crystallization concentration using the water-salt phase diagram of sodium chloride and potassium chloride to produce sodium chloride salt and potassium chloride salt.

[0018] The beneficial effects of the present invention are as follows: it has better energy consumption performance, and can effectively degrade dioxins and eliminate the problem of regeneration; countercurrent water washing can effectively reduce the chlorine content in fly ash, and has low water consumption and no dust; the selective electrodialysis device can enrich chloride ions on the monovalent ion concentrated water side and enrich reusable sulfate ions on the divalent ion concentrated water side, and can achieve the concentration and salt separation of high-salt fly ash water washing liquid without the use of additional agents, which can effectively reduce the load of the evaporation crystallizer, and the generated fresh water can also be used as water replenishment for the countercurrent water washing device, reducing the use of additional pure water. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for the embodiments or the description of the prior art. Obviously, the drawings described below are merely exemplary, and those skilled in the art can, without inventive effort, derive other implementation drawings based on the provided drawings.

[0020] The structures, proportions, sizes, etc. illustrated in this specification are intended solely to complement the contents disclosed herein and to facilitate understanding and reading by persons familiar with the art. They are not intended to limit the conditions under which the present invention may be implemented and therefore have no substantive technical significance. Any structural modifications, changes in proportions, or adjustments in size, without affecting the efficacy and objectives of the present invention, shall remain within the scope of the technical contents disclosed herein.

[0021] Figure 1 This is a schematic diagram of a waste incineration fly ash resource processing system provided in an embodiment of the present utility model.

[0022] In the figure, 1. pretreatment unit; 2. water washing liquid detoxification unit; 3. softening unit; 4. selective electrodialysis unit; 5. salt making unit; 6. low-temperature detoxification device; 7. countercurrent water washing device; 8. filter press device; 9. water washing liquid detoxification reaction tank; 10. calcium sulfate crystallizer; 11. softening reaction tank; 12. electrodialysis device; 13. evaporation crystallizer. DETAILED DESCRIPTION

[0023] To make the above-mentioned objects, features, and advantages of the present invention more clearly understood, the following detailed description of specific embodiments of the present invention is provided in conjunction with the accompanying drawings. The following description sets forth many specific details to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways than those described herein, and those skilled in the art may make similar modifications without departing from the scope of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0024] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this invention pertains. The terms used herein in the specification of this invention are intended only to describe specific embodiments and are not intended to limit this invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0025] See also Figure 1 The embodiment of the utility model provides a waste incineration fly ash resource processing system, including a pretreatment unit 1, a water washing liquid detoxification unit 2, a softening unit 3, a selective electrodialysis unit 4 and a salt production unit 5;

[0026] The pretreatment unit 1 is connected to the water washing liquid detoxification unit 2 through a conveying pipeline. The pretreatment unit 1 is used to decompose dioxins in the fly ash and remove soluble ions in the fly ash by countercurrent water washing. The water washing liquid detoxification unit 2 is used to capture heavy metal ions in the fly ash water washing liquid treated by the pretreatment unit 1.

[0027] The water washing liquid detoxification unit 2 is connected to the softening unit 3 through a conveying pipeline, and the softening unit 3 is used to remove calcium ions in the fly ash water washing liquid treated by the water washing liquid detoxification unit 2;

[0028] The softening unit 3 is connected to the selective electrodialysis unit 4 through a transmission pipeline. The selective electrodialysis unit 4 is used to separate the monovalent salt ions and divalent salt ions in the fly ash water washing liquid treated by the softening unit 3;

[0029] The selective electrodialysis unit 4 is connected to the salt-making unit 5 through a delivery pipeline, and the salt-making unit 5 is used to evaporate and crystallize the monovalent salt ions separated by the selective electrodialysis unit 4 to make salt.

[0030] In this embodiment, the pretreatment unit 1 includes a low-temperature pyrolysis device 6, a countercurrent water washing device 7 and a filter press device 8; the low-temperature pyrolysis device 6 is used to degrade dioxins in fly ash by oxygen isolation and to cool the decomposed fly ash; the countercurrent water washing device 7 is used to remove soluble ions in fly ash; and the filter press device 8 is used to separate the washed fly ash and the washing liquid.

[0031] Specifically, after being collected, waste incineration fly ash first enters pretreatment unit 1, which is equipped with a low-temperature detoxification unit 6, a countercurrent water washing unit 7, and a filter press 8. The reaction temperature in the low-temperature detoxification unit 6 is set between 400°C and 500°C, and the reaction time is controlled for 20 to 50 minutes to degrade dioxins in the fly ash. The fly ash after low-temperature pyrolysis is cooled by oxygen isolation to prevent dioxin regeneration, thereby ensuring that the dioxin content in the cooled fly ash remains below the 50ng-TEQ / kg requirement of the "Technical Specification for Pollution Control of Municipal Waste Incineration Fly Ash" (HJ1134-2020). The cooled fly ash enters countercurrent water washing unit 7 to remove soluble chloride salts and heavy metal ions. A three-stage countercurrent water washing process is used to remove soluble ions from the fly ash. The soluble chloride content of the washed product is less than 1%, and the ash-to-water mass ratio during the wash is generally 1:1-5. The washed fly ash passes through filter press 8 to achieve solid-liquid separation. The fly ash after filtration can be used to make cement, building materials, etc.

[0032] In this embodiment, the water washing liquid detoxification unit 2 includes a water washing liquid detoxification reaction tank 9, which is connected to the countercurrent water washing device 7 by a transmission pipeline. The water washing liquid detoxification unit 2 captures and solidifies heavy metal ions in the fly ash water washing liquid treated by the countercurrent water washing device 7 through the water washing liquid detoxification reaction tank 9. The softening unit 3 includes a calcium sulfate crystallizer 10 and a softening reaction tank 11. The calcium sulfate crystallizer 10 is connected to the water washing liquid detoxification reaction tank 9 by a transmission pipeline, and the softening reaction tank 11 is connected to the calcium sulfate crystallizer 10 by a transmission pipeline. The selective electrodialysis device 12 includes a monovalent selective anion exchange membrane and an anion and cation exchange membrane; the fresh water side of the selective electrodialysis device 12 is connected to the countercurrent water washing device 7 in the pretreatment unit 1 through a transmission pipeline. The selective electrodialysis unit 4 includes a selective electrodialysis device 12, which is connected to the softening reaction tank 11 by a transmission pipeline. The concentrated water side of the selective electrodialysis device 12 is connected to the calcium sulfate crystallizer 10 through a transmission pipeline; the calcium sulfate crystallizer 10 is used to react the calcium in the fly ash water washing liquid with the sulfate radicals on the divalent ion concentrated water side of the selective electrodialysis device 12 to crystallize calcium sulfate; the softening reaction tank 11 is used to remove the remaining calcium ions in the fly ash water washing liquid through sodium carbonate solution, and the softening reaction tank 11 is also used to adjust the pH value of the fly ash water washing liquid.

[0033] Specifically, the water washing liquid detoxification unit 2 is provided with a water washing liquid detoxification reaction tank 9, and a heavy metal capture agent is added to the fly ash water washing liquid to form a heavy metal precipitate, thereby removing heavy metal ions in the water washing liquid. The detoxified water washing liquid then enters the softening reaction tank 11, which is provided with a calcium sulfate crystallizer 10 and a softening reaction tank 11. In the calcium sulfate crystallizer 10, the calcium in the water washing liquid reacts with the sulfate radical on the divalent ion concentrated water side of the selective electrodialysis device 12 to crystallize high-purity calcium sulfate, thereby reducing the calcium ion concentration in the water washing liquid. The produced water from the calcium sulfate crystallizer 10 enters the softening reaction tank 11. The softening reaction tank 11 is provided with a sodium carbonate tank, a sodium carbonate dosing pump, a hydrochloric acid tank, and a hydrochloric acid dosing pump. The sodium carbonate solution is transported to the softening reaction tank 11 by the sodium carbonate dosing pump, and further reacts with the calcium ions in the tank to remove the remaining calcium ions. The hydrochloric acid is delivered to the softening reaction tank 11 by a hydrochloric acid dosing pump and is used to adjust the pH value of the water washing liquid to meet the water inlet requirement of the selective electrodialysis device 12 .

[0034] Among them, the selective electrodialysis unit 4 is equipped with a selective electrodialysis device 12, and the selective electrodialysis device 12 includes a monovalent selective anion exchange membrane and a common anion and cation exchange membrane. The selective electrodialysis device 12 can concentrate chloride ions on the monovalent ion concentrated water side and sulfate ions on the divalent ion concentrated water side. After the incoming water passes through the selective electrodialysis device 12, low-salt fresh water is produced. The monovalent ion concentrated water side ensures the high quality of the sodium chloride salt and potassium chloride salt produced by the salt production unit 5. The divalent ion concentrated water side can achieve a sulfate retention rate of more than 99% without the use of additional reagents, and the generated high-concentration sulfate solution can enter the calcium sulfate crystallizer 10 for destabilization crystallization of calcium sulfate. The water produced on the low-salt fresh water side can be used to supplement the water source of the countercurrent water washing device 7 in the pretreatment unit 1.

[0035] In this embodiment, the salt-making unit 5 includes an evaporation crystallizer 13, which is connected to the monovalent ion concentrated water side of the selective electrodialysis device 12 through a conveying pipeline. The evaporation crystallizer 13 is used to adjust the evaporation temperature and crystallization concentration using the water-salt phase diagram of sodium chloride and potassium chloride to produce sodium chloride salt and potassium chloride salt, thereby producing high-quality sodium chloride salt and potassium chloride salt, and the overall output is ultimately free of impurity salt.

[0036] The operation process of this utility model is as follows:

[0037] After collection, waste incineration fly ash first enters pretreatment unit 1, which is equipped with a low-temperature detoxification unit 6, a countercurrent water washing unit 7, and a filter press 8. The low-temperature detoxification unit 6 ensures the removal of dioxins from the fly ash through low-temperature pyrolysis. The reaction temperature of the low-temperature detoxification unit 6 is set at 400°C to 500°C, and the reaction time is controlled for 20 to 50 minutes to degrade dioxins in the fly ash. The fly ash after low-temperature pyrolysis is cooled by oxygen isolation in the low-temperature detoxification unit 6 to prevent dioxin regeneration. The cooled fly ash enters the countercurrent water washing unit 7 to remove soluble salts and heavy metal ions. The countercurrent water washing unit 7 uses a three-stage countercurrent water washing process to remove soluble ions from the fly ash. The soluble chlorine content of the washed product is less than 1%, and the ash-to-water mass ratio is generally 1:1 to 5. The washed fly ash passes through the filter press 8 to achieve solid-liquid separation. The separated solid fly ash can be used to make cement, building materials, and other materials.

[0038] The water wash detoxification unit 2 is equipped with a water wash detoxification reaction tank 9. A heavy metal capture agent is added to the fly ash water wash to form a heavy metal precipitate and remove heavy metal ions from the water wash. The detoxified water wash then enters the softening unit 3, which is equipped with a calcium sulfate crystallizer 10 and a softening reaction tank 12. In the calcium sulfate crystallizer 10, the calcium in the water wash reacts with sulfate radicals on the divalent ion concentrated water side of the selective electrodialysis device 12 to crystallize high-purity calcium sulfate, thereby reducing the calcium ion concentration in the water wash. The water produced by the calcium sulfate crystallizer 10 enters the softening reaction tank 12. The softening reaction tank 12 is equipped with a sodium carbonate tank, a sodium carbonate dosing pump, a hydrochloric acid tank, and a hydrochloric acid dosing pump. The sodium carbonate solution is transported to the softening reaction tank 12 by the sodium carbonate dosing pump, where it further reacts with the calcium ions in the tank to remove the remaining calcium ions. Hydrochloric acid is delivered to the softening reaction tank 12 via a hydrochloric acid dosing pump to adjust the pH of the wash water to meet the inlet requirements of the selective electrodialysis unit 12. The selective electrodialysis unit 4 is equipped with the selective electrodialysis unit 12, which comprises a monovalent selective anion exchange membrane and a conventional anion and cation exchange membrane. The selective electrodialysis unit 12 concentrates chloride ions in the monovalent ion concentrate side and sulfate ions in the divalent ion concentrate side. After the inlet water passes through the selective electrodialysis unit 12, it produces low-salinity fresh water. The monovalent ion concentrate side ensures the high quality of the sodium chloride and potassium chloride salts produced by the salt production unit 5. The divalent ion concentrate side achieves a sulfate rejection rate of over 99% without the use of additional reagents. The resulting high-concentration sulfate solution can be fed into the calcium sulfate crystallizer 10 for destabilization and crystallization of calcium sulfate. The water produced from the low-salinity fresh water side can be used to replenish the countercurrent water washing unit 7 in the pretreatment unit 1. The water produced from the monovalent ion concentrate side enters the salt production unit 5. The evaporation crystallizer 13 in the salt production unit 5 uses the water-salt phase diagram of sodium chloride and potassium chloride to adjust the evaporation temperature and crystallization concentration, thereby producing high-quality sodium chloride salt and potassium chloride salt. The process ultimately produces no impurity salt.

[0039] In summary, the present invention comprises a pretreatment unit 1, a water washing liquid detoxification unit 2, a softening unit 3, a selective electrodialysis unit 4 and a salt making unit 5; the pretreatment unit 1 is connected to the water washing liquid detoxification unit 2 via a delivery pipeline, and the pretreatment unit 1 is used to decompose dioxins in fly ash and separate soluble chlorides in fly ash by using three-stage countercurrent water washing; the pretreatment unit 1 is connected to the water washing liquid detoxification unit 2 via a delivery pipeline, and the water washing liquid detoxification unit 2 is used to capture heavy metal ions in the fly ash water washing liquid treated by the pretreatment unit 1; the water washing The liquid detoxification unit 2 is connected to the softening unit 3 through a conveying pipeline, and the softening unit 3 is used to remove calcium ions in the fly ash water washing liquid treated by the water washing liquid detoxification unit 2; the softening unit 3 is connected to the selective electrodialysis unit 4 through a conveying pipeline, and the selective electrodialysis unit 4 is used to separate the monovalent salt ions and divalent salt ions in the fly ash water washing liquid treated by the softening unit 3; the selective electrodialysis unit 4 is connected to the salt making unit 5 through a conveying pipeline, and the salt making unit 5 is used to evaporate and crystallize the monovalent salt ions separated by the selective electrodialysis unit 4 to make salt. The present invention has better energy consumption performance, and can effectively degrade dioxins and prevent the problem of regeneration; the three-stage countercurrent water washing can effectively reduce the chlorine content in the fly ash, and has low water consumption and no dust; the selective electrodialysis device 12 can enrich chloride ions on the monovalent ion concentrated water side and enrich reusable sulfate ions on the divalent ion concentrated water side, without the need for additional chemicals to achieve the concentration and salt separation of high-salt fly ash water washing liquid, which can effectively reduce the load of the evaporation crystallizer 13, and the generated fresh water can also be used as water supplement for the three-stage countercurrent water washing device, reducing the use of additional pure water.

[0040] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0041] The above-described embodiments merely represent several implementations of the present invention. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the utility model patent. It should be noted that a person skilled in the art would be able to make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements fall within the scope of protection of the present invention. Therefore, the scope of protection of the present utility model patent shall be determined by the appended claims.

Claims

1. A waste incineration fly ash resource processing system, characterized in that: It includes a pretreatment unit (1), a water washing liquid detoxification unit (2), a softening unit (3), a selective electrodialysis unit (4) and a salt production unit (5); The pretreatment unit (1) is connected to the water washing liquid detoxification unit (2) via a conveying pipeline, and the pretreatment unit (1) is used to decompose dioxins in fly ash and to separate soluble ions in fly ash by countercurrent water washing; The water washing liquid detoxification unit (2) is used to fix the heavy metal ions in the fly ash water washing liquid delivered by the pretreatment unit (1); The water washing liquid detoxification unit (2) is connected to the softening unit (3) via a conveying pipeline, and the softening unit (3) is used to remove calcium ions in the fly ash water washing liquid treated by the water washing liquid detoxification unit (2); The softening unit (3) is connected to the selective electrodialysis unit (4) via a conveying pipeline, and the selective electrodialysis unit (4) is used to separate monovalent salt ions and divalent salt ions in the fly ash water washing liquid treated by the softening unit (3); The selective electrodialysis unit (4) is connected to the salt-making unit (5) via a delivery pipeline, and the salt-making unit (5) is used to evaporate and crystallize the monovalent salt ions separated by the selective electrodialysis unit (4) to make salt.

2. A waste incineration fly ash resource processing system according to claim 1, characterized in that: The pretreatment unit (1) comprises a low-temperature pyrolysis device (6), a countercurrent water washing device (7) and a filter press device (8); the low-temperature pyrolysis device (6) is used to degrade dioxins in fly ash by isolating oxygen and to cool the decomposed fly ash; the countercurrent water washing device (7) is used to remove soluble ions in the fly ash; and the filter press device (8) is used to separate the washed fly ash and the washing liquid.

3. A waste incineration fly ash resource processing system according to claim 2, characterized in that: The water washing liquid detoxification unit (2) comprises a water washing liquid detoxification reaction tank (9), the water washing liquid detoxification reaction tank (9) and the pretreatment unit (1) are connected via a delivery pipeline, and the water washing liquid detoxification unit (2) captures heavy metal ions in the fly ash water washing liquid treated by the pretreatment unit (1) via the water washing liquid detoxification reaction tank (9).

4. A waste incineration fly ash resource processing system according to claim 3, characterized in that: The softening unit (3) comprises a calcium sulfate crystallizer (10) and a softening reaction tank (11), wherein the calcium sulfate crystallizer (10) is connected to the water wash liquid detoxification reaction tank (9) via a delivery pipeline, and the softening reaction tank (11) is connected to the calcium sulfate crystallizer (10) via a delivery pipeline; The selective electrodialysis unit (4) includes a selective electrodialysis device (12), the selective electrodialysis device (12) and the softening reaction tank (11) are connected via a delivery pipeline, and the concentrated water side of the selective electrodialysis device (12) is connected to the calcium sulfate crystallizer (10) via a delivery pipeline; The calcium sulfate crystallizer (10) is used to react calcium in the fly ash water wash with sulfate radicals on the divalent ion concentrated water side of the selective electrodialysis device (12) to crystallize calcium sulfate; the softening reaction tank (11) is used to remove residual calcium ions in the fly ash water wash by using a sodium carbonate solution, and the softening reaction tank (11) is also used to adjust the pH value of the fly ash water wash.

5. A waste incineration fly ash resource processing system according to claim 4, characterized in that: The selective electrodialysis device (12) comprises a monovalent selective anion exchange membrane and an anion and cation exchange membrane; The fresh water side of the selective electrodialysis device (12) is connected to the pretreatment unit (1) via a delivery pipeline for reuse.

6. A waste incineration fly ash resource processing system according to claim 5, characterized in that: The salt production unit (5) includes an evaporation crystallizer (13), which is connected to the monovalent ion concentrated water side of the selective electrodialysis device (12) through a transmission pipeline. The evaporation crystallizer (13) is used to adjust the evaporation temperature and crystallization concentration using the water-salt phase diagram of sodium chloride and potassium chloride to produce sodium chloride salt and potassium chloride salt.

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