A high-salt wastewater treatment system and method

Abstract

The present invention relates to the technical field of wastewater treatment, and particularly to a high-salt wastewater disposal system and method. The high-salt wastewater treatment system provided by the present invention includes: a primary wet acid removal tower, a secondary wet acid removal tower, a high-salt water crystallization mother tank, a high-salt water crystallization sub-tank, a quench water tank, a quench tower, and a two-fluid spray gun; the high-salt wastewater discharge outlets of the primary wet acid removal tower and the secondary wet acid removal tower lead to the high-salt water crystallization mother tank; the supernatant outlet of the high-salt water crystallization mother tank leads to the high-salt water crystallization sub-tank or the primary wet acid removal tower; the high-salt water outlet in the high-salt water crystallization sub-tank leads to the quench water tank, and the liquid outlet in the quench water tank leads to the two-fluid spray gun; the two-fluid spray gun leads to the quench tower. The implementation of the present invention can reduce costs, effectively avoid salt crystallization in the quench tower and gun blockage, and achieve stable operation of the equipment.

Description

Technical Field

[0001] The present invention relates to the technical field of wastewater treatment, and particularly to a high-salt wastewater disposal system and method. Background Art

[0002] Incineration disposal is the fastest and most effective technology for the reduction, resource utilization, and harmless treatment of hazardous waste. A large amount of high-salt wastewater is generated during the wet flue gas desulfurization process involved in the basic process of hazardous waste incineration disposal.

[0003] Currently, there are two disposal processes for high-salt wastewater: one is the evaporation crystallization process, which uses a double-effect or single-effect or triple-effect evaporator to evaporate and crystallize high-salt water. Due to large equipment investment, consumption of a large amount of steam, and complex operating conditions, the operating cost is high and the operation is unstable; the other is the method of spraying high-salt water back into the quench tower for treatment. In this method, if no salt inhibitor is added, the spray gun is prone to blockage and the quench tower wall is prone to salt deposition, seriously affecting the normal operation of the incineration system, thus greatly increasing the operating cost; if a salt inhibitor is added, due to the high price of the salt inhibitor, nearly 100,000 yuan per ton, the operating cost is high.

[0004] In summary, the current disposal processes for high-salt wastewater all have the defects of high operating cost and unstable operation. Summary of the Invention

[0005] Regarding the defects existing in the prior art, the present invention aims to propose a new process and operation plan for spraying high-salt wastewater back into the quench tower without adding a salt inhibitor, and reasonably transform the quench tower to ensure low-cost and long-term stable operation.

[0006] The high-salt wastewater treatment system provided by the present invention is characterized in that: the system includes: a primary wet desulfurization tower, a secondary wet desulfurization tower, a high-salt water crystallization mother tank, a high-salt water crystallization sub-tank, a quench water tank, a quench tower, and a two-fluid spray gun; the high-salt wastewater discharge outlets of the primary wet desulfurization tower and the secondary wet desulfurization tower lead to the high-salt water crystallization mother tank; the supernatant outlet of the high-salt water crystallization mother tank leads to the high-salt water crystallization sub-tank or the primary wet desulfurization tower; the high-salt water outlet in the high-salt water crystallization sub-tank leads to the quench water tank, and the liquid outlet in the quench water tank leads to the two-fluid spray gun; the two-fluid spray gun leads to the quench tower.

[0007] Specifically, the high-salt wastewater discharge outlets of the primary wet desulfurization tower and the secondary wet desulfurization tower are connected to the high-salt water crystallization mother tank through a water pump and a pipeline; the supernatant outlet of the high-salt water crystallization mother tank is connected to the high-salt water crystallization sub-tank or the primary wet desulfurization tower through a pipeline; the high-salt water outlet in the high-salt water crystallization sub-tank is connected to the quench water tank through a water pump and a pipeline, and the liquid outlet in the quench water tank is connected to the two-fluid spray gun through a water pump and a pipeline; each device is provided with a switch valve.

[0008] Specifically, the primary wet desulfurization tower is connected to a primary tower circulation pump, and the secondary wet desulfurization tower is connected to a secondary tower circulation pump.

[0009] Specifically, the primary wet desulfurization tower, the secondary wet desulfurization tower, and the quench tower are all provided with a flue gas inlet and a flue gas outlet; the flue gas outlet of the primary wet desulfurization tower leads to the flue gas inlet of the secondary wet desulfurization tower.

[0010] Further, a filter is provided in front of the water pump between the high-salt water outlet in the high-salt water crystallization sub-tank and the quench water tank.

[0011] Further, a filter is provided in front of the water pump between the liquid outlet in the quench water tank and the two-fluid spray gun.

[0012] Further, the high-salt wastewater treatment system provided by the present invention further includes a fluid pressure stabilizing system, and the fluid pressure stabilizing system is connected to the two-fluid spray gun to ensure that the atomized droplet diameter and the running track of the two-fluid spray gun reach the design indexes.

[0013] Specifically, the fluid pressure stabilizing system includes a quench water pressure stabilizing tank, a compressed air pressure stabilizing tank, and a protective air pressure stabilizing pipe.

[0014] Specifically, a thin film material for preventing salt crystallization and water infiltration expansion is sprayed inside the quench tower. A hopper and an ash outlet are provided at the bottom of the quench tower, and the diameter of the ash outlet is 800-1000 mm; an air outlet is provided on the quench tower, and the position of the air outlet is set at the entrance of the hopper.

[0015] Further, the high-salt wastewater treatment system provided by the present invention further includes a salt box and an ash box. The bottom of the high-salt water crystallization mother tank is connected to the salt box, and the ash outlet of the quench tower is connected to the ash box.

[0016] Meanwhile, the present invention also provides a method for treating high-salt wastewater, including the following steps:

[0017] The high-salt wastewater enters the high-salt water crystallization mother tank from the primary wet desulfurization tower and the secondary wet desulfurization tower;

[0018] The supernatant of the high-salt water crystallization mother tank overflows into the high-salt water crystallization sub-tank or overflows into the primary wet desulfurization tower; the crystal salt, concentrated brine, and sediment are discharged from the bottom of the high-salt water crystallization mother tank;

[0019] The high-salt wastewater enters the quench water tank from the high-salt water crystallization sub-tank. After being mixed with other wastewater or industrial makeup water in the quench water tank, it is atomized by a two-fluid spray gun and sprayed into the quench tower;

[0020] In the quench tower, the flue gas and the high-salt water mist perform rapid heat exchange in the quench tower. The high-salt water mist is completely evaporated and incorporated into the flue gas, and the evaporated salt and solid particles in the flue gas are discharged from the bottom of the quench tower.

[0021] Specifically, in the quench tower, high-temperature flue gas above 500 °C and high-salt water mist undergo rapid heat exchange in the quench tower. The high-temperature flue gas is cooled to below 200 °C within 1 s. The high-salt water mist completely evaporates and merges into the flue gas. The evaporated salts and solid particles in the flue gas are discharged from the bottom of the quench tower.

[0022] Furthermore, the conductivity of the secondary wet desulfurization tower is controlled within a set range. When the conductivity exceeds the upper limit, the circulating spray liquid of the secondary wet desulfurization tower is discharged into the primary wet desulfurization tower through the secondary tower circulating pump, and stops when it is lower than the lower limit of the conductivity value; the conductivity of the primary wet desulfurization tower is controlled within a set range. When the conductivity exceeds the upper limit, the high-salt wastewater is discharged from the primary wet desulfurization tower into the high-salt wastewater crystallization mother tank, and stops when it is lower than the lower limit.

[0023] Specifically, in the above method, the conductivity of the secondary wet desulfurization tower is controlled at 20 - 60 ms / cm. When the conductivity exceeds the upper limit, the circulating spray liquid of the secondary wet desulfurization tower is discharged into the primary wet desulfurization tower through the secondary tower circulating pump, and stops when it is lower than the lower limit of the conductivity value; the conductivity of the primary wet desulfurization tower is controlled at 80 - 120 ms / cm. When the conductivity exceeds the upper limit, the high-salt wastewater is discharged from the primary wet desulfurization tower into the high-salt water crystallization mother tank, and stops when it is lower than the lower limit.

[0024] Furthermore, in the above method, the conductivity of the wastewater discharged from the primary wet desulfurization tower is increased to 160 - 200 ms / cm.

[0025] Specifically, for the fluid pressure stabilizing system connected to the two-fluid spray gun, the atomized droplet size and operation trajectory of the two-fluid spray gun are determined according to the design specifications.

[0026] Specifically, the liquid atomized by the two-fluid spray gun is sprayed into the quench tower in the form of droplets with a maximum particle size less than 80 μm and an average particle size less than 50 μm.

[0027] The present invention has the following beneficial effects:

[0028] 1. Low investment cost. There is no investment in the evaporator system or salt inhibitor system, significantly reducing the investment cost.

[0029] 2. Low operating cost. The evaporation crystallization process requires consumption of steam (at least 0.6 tons of steam per ton of high-salt water), chemicals, electricity, labor and maintenance costs. The process of adding salt inhibitor and backspray quenching requires consumption of 0.2% - 2% of high-price salt inhibitor, while the present invention has almost no additional operating cost.

[0030] 3. It operates reliably. Due to the complex quality and high harmful component content of high-salt water, the evaporation crystallization process has a high failure rate, and the inner wall of the tube bundle is prone to scaling; in the process of adding a salt inhibitor and backspraying for rapid cooling, it is difficult to adjust the addition amount of the salt inhibitor in a timely manner, resulting in frequent occurrences of gun jams and salt caking on the wall. However, the present invention adopts an external tower circulation salt crystallization mode, realizes the circulation of high-salt water between the high-salt water crystallization mother tank and the wet tower, and realizes partial crystallization and precipitation of high-salt water in the high-salt water crystallization mother tank, thereby greatly reducing the salt crystallization cost of part of the high-salt water and effectively avoiding gun jams, which is beneficial to the treatment of high-salinity high-salt water.

[0031] 4. Due to the stable fluid and reasonable control parameters, the dual-fluid spray gun in the rapid cooling tower can ensure no dripping at the tower bottom; in addition, the inner wall of the rapid cooling tower is treated to prevent salt crystallization and the ash hopper discharges ash smoothly, so there is no "salt accumulation and caking" phenomenon on the inner wall of the rapid cooling tower; the solution of the present invention operates reliably and can achieve long-term stable operation.

[0032] 5. It can handle a large amount of wastewater. It not only realizes the full backspray of high-salt water into the rapid cooling tower, that is, zero discharge of high-salt water; but also part of the initial rainwater and other wastewater can be backsprayed into the rapid cooling tower. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is a schematic structural diagram of a high-salt wastewater treatment system in a specific embodiment of the present invention;

[0034] Figure 2 It is a schematic flow diagram of the high-salt wastewater disposal method provided by the present invention;

[0035] Figure 3 It is a photo of the salt crystallization situation in the high-salt water crystallization mother tank taken in a specific implementation of the present invention;

[0036] Figure 4 Photos of the salt crystallization on the wall of the rapid cooling tower and the ash discharge from the ash hopper taken before the implementation of the technical solution of the present invention;

[0037] Figure 5 Photos of the salt crystallization on the wall of the rapid cooling tower and the ash discharge from the ash hopper taken after applying the technical solution of the present invention.

[0038] Reference numerals: 1 secondary wet desulfurization tower; 2 secondary tower circulation pump; 3 primary wet desulfurization tower; 4 primary tower circulation pump; 5 water pump; 6 high-salt water crystallization mother tank; 7 high-salt water crystallization sub-tank; 8 salt box; 9 water pump; 10 rapid cooling water tank; 11 water pump; 12 compressed air pressure stabilizing tank; 13 protection air pressure stabilizing pipe; 14 rapid cooling water pressure stabilizing tank; 15 fluid pressure stabilizing system; 16 dual-fluid spray gun; 17 rapid cooling tower; 18 ash box. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0039] To make the objectives, features, and advantages of the present invention more apparent and understandable, the following provides a detailed description of the specific embodiments of the present invention with reference to the accompanying drawings. Specific details are set forth in the following description to facilitate a thorough understanding of the present invention. Those skilled in the art can make similar improvements without departing from the concept of the present invention. Therefore, the protection scope of the present invention is not limited by the specific embodiments disclosed below.

[0040] As Figure 1 shown, in a specific embodiment provided by the present invention, the high-salt wastewater treatment system includes: a primary wet desulfurization tower 3, a secondary wet desulfurization tower 1, a high-salt water crystallization mother tank 6, a high-salt water crystallization sub-tank 7, a quench water tank 10, a quench tower 17, and a two-fluid spray gun 16; the high-salt wastewater discharge outlets of the primary wet desulfurization tower 3 and the secondary wet desulfurization tower 1 lead to the high-salt water crystallization mother tank 6; the supernatant outlet of the high-salt water crystallization mother tank 6 leads to the high-salt water crystallization sub-tank 7 or the primary wet desulfurization tower 3; the high-salt water outlet in the high-salt water crystallization sub-tank 7 leads to the quench water tank 10, and the liquid outlet in the quench water tank 10 leads to the two-fluid spray gun 16; the two-fluid spray gun 16 leads to the quench tower 17. The high-salt wastewater discharge outlets of the primary wet desulfurization tower 3 and the secondary wet desulfurization tower 1 are connected to the high-salt water crystallization mother tank 6 through a high-salt water pump 5 and a pipeline; the supernatant outlet of the high-salt water crystallization mother tank 6 is connected to the high-salt water crystallization sub-tank 7 or the primary wet desulfurization tower 3 through a pipeline; the high-salt water outlet in the high-salt water crystallization sub-tank 7 is connected to the quench water tank 10 through a high-salt water pump 9 and a pipeline, and the liquid outlet in the quench water tank 10 is connected to the two-fluid spray gun 16 through a water pump 11 and a pipeline; each device is provided with a switch valve (not shown).

[0041] In a specific embodiment, the primary wet desulfurization tower 3 of the high-salt wastewater treatment system is connected to a primary tower circulation pump 4, and the secondary wet desulfurization tower 1 is connected to a secondary tower circulation pump 2.

[0042] In a specific embodiment, the primary wet desulfurization tower 3, the secondary wet desulfurization tower 1, and the quench tower 17 of the high-salt wastewater treatment system are all provided with a flue gas inlet and a flue gas outlet; the flue gas outlet of the primary wet desulfurization tower 3 leads to the flue gas inlet of the secondary wet desulfurization tower 1.

[0043] In a specific embodiment, a filter is provided in front of the water pump 9 between the high-salt water outlet in the high-salt water crystallization sub-tank 7 of the high-salt wastewater treatment system and the quench water tank 10.

[0044] In a specific embodiment, a filter is provided in front of the water pump 11 between the liquid outlet in the quench water tank 10 of the high-salt wastewater treatment system and the two-fluid spray gun 16.

[0045] In a specific embodiment, the high-salt wastewater treatment system further includes a fluid pressure stabilizing system 15. The fluid pressure stabilizing system 15 is connected to a dual-fluid spray gun 16. The fluid pressure stabilizing system 15 includes a quench water pressure stabilizing tank 12, a compressed air pressure stabilizing tank 13, and a protective air pressure stabilizing pipe 14.

[0046] In a specific embodiment, a thin film material for preventing salt deposition and water infiltration expansion is sprayed inside the quench tower 17 of the high-salt wastewater treatment system. A dust hopper and an ash discharge port are provided at the bottom of the quench tower 17, and the diameter of the ash discharge port is selected to be 800 - 1000 mm; an air outlet is provided on the quench tower 17, and the position of the air outlet is set at the entrance of the dust hopper.

[0047] In a specific embodiment, the high-salt wastewater treatment system further includes a salt tank 8 and an ash box 18. The bottom of the high-salt water crystallization mother tank 6 is connected to the salt tank 8, and the ash discharge port of the quench tower 17 is connected to the ash box 18.

[0048] In specific implementation, a high-temperature nano-functional thin film material is sprayed on the inner wall of the quench tower 17. The coating has antioxidant, anti-corrosion, anti-coking, anti-adhesion properties, and a smooth surface, which can effectively inhibit "salt and water infiltration expansion"; the diameter of the ash discharge port at the bottom ash hopper of the quench tower 17 is enlarged from 400 mm to 900 mm (the preferred size of the diameter is 800 - 1000 mm), and the position of the air outlet is moved up to the upper opening of the dust hopper to ensure smooth ash discharge and flue gas, thus completely solving the problems of salt deposition on the tower wall and bottom, ash discharge, and poor ventilation; a fluid pressure stabilizing system 15 is provided in front of the dual-fluid spray gun; a quench water pressure stabilizing tank 12, a compressed air pressure stabilizing tank 13, and a protective air pressure stabilizing pipe 14 are provided to ensure stable and reliable pressures of the compressed air, high-salt water, and protective air of the spray gun; furthermore, it is ensured that the water mist particles formed by the dual-fluid spray gun are less than 80 um and run according to the designed trajectory.

[0049] As Figure 2 shown, the present invention also provides a method for treating high-salt wastewater. The following steps are adopted in specific implementation:

[0050] The high-salt wastewater enters the high-salt water crystallization mother tank 6 from the primary wet desulfurization tower 3 and the secondary wet desulfurization tower 1;

[0051] The supernatant of the high-salt water crystallization mother tank 6 overflows into the high-salt water crystallization sub-tank 7, or overflows into the primary wet desulfurization tower 3; the crystal salts or concentrated brines and precipitates are discharged from the bottom of the high-salt water crystallization mother tank 7;

[0052] The high-salt wastewater enters the quench water tank 10 from the high-salt water crystallization sub-tank 7. After being mixed with other wastewater or industrial makeup water in the quench water tank 10, it is atomized and sprayed into the quench tower 17 through the dual-fluid spray gun 16;

[0053] In the quench tower 17, the flue gas and the high-salt water mist perform rapid heat exchange in the quench tower 17. The high-salt water mist completely evaporates and merges into the flue gas, and the evaporated salts and solid particles in the flue gas are discharged from the bottom of the quench tower.

[0054] During the implementation of the high-salt wastewater treatment method, better effects can be achieved through optimized settings.

[0055] In a specific embodiment, the high-salt wastewater is pumped from the high-salt water crystallization sub-tank 7 into the quench water tank 10 through the high-salt water pump 9. After being mixed with other wastewater or industrial makeup water in the quench water tank 10, it is atomized into droplets with a maximum particle size less than 80 μm and an average particle size less than 50 μm by a pump and a two-fluid spray gun and sprayed into the quench tower; a fluid pressure stabilizing system is arranged in front of the two-fluid spray gun, which can ensure that the atomized droplet particle size and the running track of the two-fluid spray gun reach the design indexes; thus ensuring dry ash discharge at the bottom of the quench tower, no wet wall, and no dripping at the bottom of the tower.

[0056] In a specific embodiment, in the quench tower, in the quench tower 17, the high-temperature flue gas above 500 °C and the high-salt water mist perform rapid heat exchange in the quench tower. The high-temperature flue gas is reduced to below 200 °C within 1 s. The high-salt water mist completely evaporates and merges into the flue gas, and the evaporated salts and solid particles in the flue gas are discharged from the ash hopper at the bottom of the quench tower 17. A small part of the lighter particles reach the dust collector and are collected together with the fly ash.

[0057] In a specific embodiment, the conductivity of the secondary wet desulfurization tower 1 is controlled at 20 - 60 ms / cm. When the upper limit of the conductivity value is exceeded, a part of the circulating spray liquid of the secondary wet desulfurization tower 1 is discharged into the primary wet desulfurization tower 3 through the secondary tower circulating pump 2, and it stops when it is lower than the lower limit of the conductivity value; the conductivity of the primary wet desulfurization tower 3 is controlled at 80 - 120 ms / cm. When the upper limit of the conductivity value is exceeded, the high-salt wastewater is discharged from the primary wet desulfurization tower 3 into the high-salt water crystallization mother tank 6, and it stops when it is lower than the lower limit of the conductivity value.

[0058] When it is necessary to increase the salt crystallization amount in the high-salt water crystallization mother tank or when the liquid level of the high-salt water crystallization mother tank is high and the water is difficult to be discharged in time, the water circulation between the high-salt water crystallization mother tank 6 and the primary wet desulfurization tower 3 can be appropriately increased or the upper and lower limits of the conductivity of the primary wet desulfurization tower 3 can be appropriately increased to 160 - 200 ms / cm.

[0059] Figure 3 It can be seen that in the specific implementation of the present invention, after treating 5000 tons of wastewater and operating for two months, the salt crystallization situation in the high-salt water crystallization mother tank shows that the high-salt wastewater realizes salt crystallization in the high-salt water crystallization mother tank, verifying the success of "out-of-tower cyclic salt crystallization" and avoiding equipment failures caused by salt crystallization in subsequent equipment pipelines.

[0060] To compare the effects before and after the implementation of the technical solution of the present invention, photos of salt deposition on the quench tower wall and ash discharge from the ash hopper before and after the implementation were taken. It can be seen that after the implementation of the technical solution provided by the present invention, the phenomenon of salt deposition on the quench tower wall has been completely improved.

[0061] Figure 4 It is the condition inside the quench tower for treating 3,000 tons of high-salt wastewater before implementation. At the same time, the ash discharge port of the ash hopper is blocked and there is serious dripping; the operating resistance of the system increases and the operating load is reduced by more than 30%. Figure 5 It is the condition inside the quench tower for treating 16,000 tons of high-salt wastewater after implementation. There is no "salt accumulation and caking" inside the tower, and there is only a thin layer of floating ash on the tower wall, and the system operates normally.

Claims

1. A method for treating high-salt wastewater, characterized in that: It is carried out by using a high-salt wastewater treatment system, and the high-salt wastewater treatment system includes: a primary wet desulfurization tower, a secondary wet desulfurization tower, a high-salt water crystallization mother tank, a high-salt water crystallization sub-tank, a quench water tank, a quench tower, and a two-fluid spray gun; a thin film material for preventing salt deposition and water infiltration expansion is sprayed inside the quench tower; the high-salt wastewater discharge outlets of the primary wet desulfurization tower and the secondary wet desulfurization tower lead to the high-salt water crystallization mother tank; the supernatant outlet of the high-salt water crystallization mother tank leads to the high-salt water crystallization sub-tank or the primary wet desulfurization tower; the high-salt water outlet in the high-salt water crystallization sub-tank leads to the quench water tank, and the liquid outlet in the quench water tank leads to the two-fluid spray gun; the two-fluid spray gun leads to the quench tower; the treatment method includes the following steps: The high-salt wastewater enters the high-salt water crystallization mother tank from the primary wet desulfurization tower and the secondary wet desulfurization tower; the supernatant of the high-salt water crystallization mother tank overflows into the high-salt water crystallization sub-tank or overflows into the primary wet desulfurization tower; the crystal salts, concentrated brine and precipitates are discharged from the bottom of the high-salt water crystallization mother tank; the high-salt wastewater enters the quench water tank from the high-salt water crystallization sub-tank, and after being mixed with other wastewater or industrial makeup water in the quench water tank, it is atomized and sprayed into the quench tower through the two-fluid spray gun; the fluid pressure stabilizing system connected to the two-fluid spray gun determines the atomized droplet size and running trajectory of the two-fluid spray gun according to the design index, and the liquid atomized by the two-fluid spray gun is sprayed into the quench tower as droplets with a maximum particle size less than 80 μm and an average particle size less than 50 μm; in the quench tower, the flue gas and the high-salt water mist perform rapid heat exchange in the quench tower, the high-salt water mist is completely evaporated and incorporated into the flue gas, and the evaporated salts and solid particles in the flue gas are discharged from the bottom of the quench tower.

2. The high-salt wastewater treatment method according to claim 1, characterized in that: The high-salt wastewater discharge outlets of the primary wet desulfurization tower and the secondary wet desulfurization tower are connected to the high-salt water crystallization mother tank through a water pump and a pipeline; the supernatant outlet of the high-salt water crystallization mother tank is connected to the high-salt water crystallization sub-tank or the primary wet desulfurization tower through a pipeline; the high-salt water outlet in the high-salt water crystallization sub-tank is connected to the quench water tank through a water pump and a pipeline, and the liquid outlet in the quench water tank is connected to the two-fluid spray gun through a water pump and a pipeline; each device is provided with a switch valve.

3. The high-salt wastewater treatment method according to claim 1 or 2, characterized in that: The primary wet desulfurization tower is connected to a primary tower circulation pump, and the secondary wet desulfurization tower is connected to a secondary tower circulation pump.

4. The high-salt wastewater treatment method according to claim 3, characterized in that: The primary wet desulfurization tower, the secondary wet desulfurization tower, and the quench tower are all provided with a flue gas inlet and a flue gas outlet; the flue gas outlet of the primary wet desulfurization tower leads to the flue gas inlet of the secondary wet desulfurization tower.

5. The high-salt wastewater treatment method according to claim 3, characterized in that: Filters are provided in front of the water pump between the high-salt water outlet in the high-salt water crystallization sub-tank and the quench water tank; filters are provided in front of the water pump between the liquid outlet in the quench water tank and the two-fluid spray gun.

6. The high-salt wastewater treatment method according to claim 5, wherein: It also includes a fluid pressure stabilizing system, and the fluid pressure stabilizing system is connected to the two-fluid spray gun. The fluid pressure stabilizing system includes a quench water pressure stabilizing tank, a compressed air pressure stabilizing tank, and a protective air pressure stabilizing pipe.

7. The high-salt wastewater treatment method according to claim 6, characterized in that: A hopper and an ash discharge port are provided at the bottom of the quench tower, and the diameter of the ash discharge port is 800 - 1000 mm; an air outlet is provided on the quench tower, and the position of the air outlet is set at the entrance of the hopper.

8. The high-salt wastewater treatment method according to claim 1, characterized in that: The system also includes a salt box and an ash box. The bottom of the high-salt water crystallization mother tank is connected to the salt box, and the ash discharge port of the quench tower is connected to the ash box.

9. The high-salt wastewater treatment method according to claim 1, wherein: In the quench tower, high-temperature flue gas above 500 °C undergoes rapid heat exchange with high-salt water mist. The high-temperature flue gas is cooled to below 200 °C within 1 s. The high-salt water mist completely evaporates and merges into the flue gas. The evaporated salts and solid particles in the flue gas are discharged from the bottom of the quench tower.

10. The high-salt wastewater treatment method according to claim 1, characterized in that: Control the conductivity of the secondary wet desulfurization tower within the set range. When the conductivity exceeds the upper limit, the circulating spray liquid of the secondary wet desulfurization tower is discharged into the primary wet desulfurization tower through the secondary tower circulation pump and stops when it is below the lower limit of the conductivity value; control the conductivity of the primary wet desulfurization tower within the set range. When the conductivity exceeds the upper limit, the high-salt wastewater is discharged from the primary wet desulfurization tower into the high-salt water crystallization mother tank and stops when it is below the lower limit.

11. The high-salt wastewater treatment method according to claim 10, characterized in that: Control the conductivity of the secondary wet desulfurization tower at 20 - 60 ms / cm. When the conductivity exceeds the upper limit, the circulating spray liquid of the secondary wet desulfurization tower is discharged into the primary wet desulfurization tower through the secondary tower circulation pump and stops when it is below the lower limit of the conductivity value; control the conductivity of the primary wet desulfurization tower at 80 - 120 ms / cm. When the conductivity exceeds the upper limit, the high-salt wastewater is discharged from the primary wet desulfurization tower into the high-salt water crystallization mother tank and stops when it is below the lower limit.

12. The high-salt wastewater treatment method according to claim 11, wherein: Increase the conductivity of the wastewater discharged from the primary wet desulfurization tower to 160 - 200 ms / cm.

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