Open-type evaporation sewage purification device for ammonia distillation waste liquid and sodium carbonate production system by ammonia-soda process

Abstract

The utility model relates to the field of wastewater treatment, and provides an open type evaporation sewage purification device for ammonia distillation waste liquid and an ammonia-alkali process sodium carbonate production system. The open type evaporation sewage purification device for the distilled ammonia waste liquid comprises a solar pond, a heat regenerator, a generation tower, an absorption tower, a fan, a recooler and a gas-liquid separator, the solar pond is communicated with a liquid inlet in the upper part of the generation tower, a gas outlet in the top of the generation tower is communicated with a gas inlet in the bottom of the absorption tower through a pipeline, and a gas outlet in the top of the absorption tower is communicated with the gas inlet in the bottom of the generation tower through a pipeline sequentially passing through the recooler and the gas-liquid separator; a circulating waste liquid outlet is formed in the lower part of the generation tower and is communicated with a liquid inlet in the upper part of the generation tower through a pipeline passing through the heat regenerator; a circulating purified water outlet is formed in the lower part of the absorption tower and is communicated with a liquid inlet in the upper part of the absorption tower through a pipeline passing through the heat regenerator. According to the sewage purification device, a large amount of purified water can be recycled from the ammonia distillation waste liquid, so that zero discharge of wastewater is realized.

Description

Technical Field

[0001] The utility model relates to the field of wastewater treatment, in particular to an open evaporation sewage purification device for ammonia waste liquid and an ammonia-soda process soda ash production system. Background Art

[0002] The ammonia-soda process involves a large amount of solid, liquid and gaseous waste in the production of soda ash, especially the production of waste liquid and waste residue, which is also very harmful to the environment and human body. 3 The ammonia waste liquid contains about 350kg of solid waste residue, and 0.5m 3 The waste sludge contains about 100kg of solid waste residue. The waste liquid discharged from ammonia evaporation is a suspension with a pH value of about 12, which contains 3% to 5% solid matter, and the solid particles are fine. The liquid phase contains a large amount of soluble salts, making solid-liquid separation difficult.

[0003] Soda ash is a bulk industrial product with a large production scale, so the amount of waste liquid discharged during production is also relatively large. Considering the cost and convenience of discharging waste liquid and alkali slag, many large ammonia-soda plants in China are built on the seaside. The slag yard is mainly built by building earth and stone dams and dikes, and the waste liquid is sent into the dam to be naturally clarified and naturally desalinated. The pH value and turbidity of the clear liquid are qualified before being discharged into the sea. The solid waste slag can be deposited in the dam body, which is relatively large in volume. At the same time, after being fully deposited, it will not dry up for many years, which will occupy a large amount of land and waste huge time and financial resources.

[0004] In view of this, this application is hereby filed. Utility Model Content

[0005] The purpose of the utility model is to provide an open evaporation wastewater purification device for ammonia evaporation wastewater and an ammonia-soda process soda ash production system. In view of the problems mentioned in the background technology, the utility model provides a new idea for the treatment of ammonia-soda process wastewater. The open evaporation wastewater purification device for ammonia evaporation wastewater provided by the application can realize the concentration of wastewater and the recovery of clean water; while solving the environmental pollution problem, it improves the use value of resources, turns waste into treasure, and promotes the common development of multiple industries such as industry and environmental ecology.

[0006] The embodiment of the utility model is achieved as follows:

[0007] In a first aspect, the utility model provides an open evaporative sewage purification device for ammonia waste liquid, comprising a solar pool, a regenerator, a generating tower, an absorption tower, a fan, a recooler, a gas-liquid separator, a dosing box, a clarification barrel and a filter press;

[0008] The solar pool is connected to the liquid inlet at the top of the generating tower, the gas outlet at the top of the generating tower is connected to the gas inlet at the bottom of the absorbing tower through a pipeline, and the gas outlet at the top of the absorbing tower is connected to the gas inlet at the bottom of the generating tower through a pipeline that passes through a recooler and a gas-liquid separator in sequence;

[0009] The lower part of the generating tower is provided with a circulating waste liquid outlet, which is connected to the liquid inlet at the upper part of the generating tower through a pipeline passing through the regenerator, and the circulating waste liquid passing through the regenerator provides a cold source for the regenerator;

[0010] The lower part of the absorption tower is provided with a circulating clean water outlet, which is connected to the liquid inlet at the upper part of the absorption tower through a pipeline passing through the regenerator, and the circulating clean water passing through the regenerator provides a heat source for the regenerator;

[0011] The fan is arranged on the pipeline between the air outlet at the top of the generating tower and the air inlet at the bottom of the absorbing tower;

[0012] The drug discharge port of the drug adding box is communicated with the opening of the clarification barrel, the waste residue discharge port at the bottom of the clarification barrel is communicated with the filter press, and the middle part of the clarification barrel is communicated with the solar pond.

[0013] In an optional embodiment, a cooler is further provided between the regenerator and the liquid inlet at the upper portion of the absorption tower.

[0014] In an optional embodiment, a clean water discharge pipe is connected to the pipeline between the cooler and the regenerator.

[0015] In an optional embodiment, the open evaporative absorption wastewater purification device also includes a liquid storage tank, which is arranged on a pipe connecting the liquid inlet of the generating tower and the circulating waste liquid outlet, and the liquid storage tank is located between the liquid inlet of the generating tower and the regenerator. At the same time, the liquid storage tank is also located on the pipe between the solar pool and the liquid inlet on the upper part of the generating tower.

[0016] In an optional embodiment, a first nozzle for downward spraying connected to a liquid inlet of the generating tower is provided at the top of the generating tower, and a first demister is also provided between the first nozzle and the gas outlet of the generating tower.

[0017] In an optional embodiment, a second nozzle for downward spraying connected to the liquid inlet of the absorption tower is provided at the top of the absorption tower, and a second demister is also provided between the second nozzle and the gas outlet of the absorption tower.

[0018] In an optional embodiment, the open evaporation absorption sewage purification device further includes an agitator, the waste residue discharge port at the bottom of the clarification barrel is connected to the agitator, and the agitator is connected to the filter press;

[0019] A waste residue discharge port is arranged at the bottom of the generating tower, and the waste residue discharge port is communicated with the agitator.

[0020] In a second aspect, the utility model provides an ammonia-soda process soda ash production system, comprising an open evaporation absorption wastewater purification device as described in any of the aforementioned embodiments.

[0021] The beneficial effects of the embodiments of the utility model are:

[0022] The open evaporation sewage purification device for ammonia waste liquid provided by the utility model can realize the recovery of a large amount of pure water from the ammonia waste liquid due to the specific arrangement of the solar pool, the regenerator, the generating tower, the absorption tower, the fan, the recooler and the gas-liquid separator, thereby realizing zero discharge of waste water; the waste liquid is heated by heating the cooling water or the process water after being supplemented with heat by the solar pool, thereby realizing the recovery and utilization of industrial waste heat. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions of the embodiments of the utility model, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the utility model and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying creative work.

[0024] Figure 1 A schematic structural diagram of an open evaporative sewage purification device for ammonia waste liquid provided in an embodiment of the utility model.

[0025] Icons: 101-solar pool; 102-regenerator; 103-generator tower; 104-absorption tower; 105-fan; 106-recooler; 107-gas-liquid separator; 108-cooler; 109-clean water discharge pipe; 110-liquid storage tank; 111-first nozzle; 112-first demister; 113-second nozzle; 114-second demister; 115-dosage box; 116-clarification barrel; 117-filter press; 118-mixer; 120-waste residue pool. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical scheme and advantages of the embodiments of the utility model clearer, the technical scheme in the embodiments of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiments of the utility model. Obviously, the described embodiments are part of the embodiments of the utility model, not all of the embodiments. Generally, the components of the embodiments of the utility model described and shown in the drawings here can be arranged and designed in various different configurations.

[0027] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the present invention to be protected, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0029] In the description of the present utility model, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. indicate the orientation or position relationship based on the orientation or position relationship shown in the accompanying drawings, or the orientation or position relationship in which the utility model product is usually placed when in use, which is only for the convenience of describing the utility model and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present utility model. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0030] In addition, the terms "horizontal", "vertical" and the like do not mean that the components are required to be absolutely horizontal or suspended, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0031] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0032] like Figure 1 As shown, an open evaporation sewage purification device for ammonia waste liquid provided by an embodiment of the utility model includes a solar pool 101, a heat regenerator 102, a generating tower 103, an absorption tower 104, a fan 105, a recooler 106, a gas-liquid separator 107, a dosing box 115, a clarification tank 116 and a filter press 117.

[0033] The solar pool 101 is filled with wastewater, and sunlight is used to heat the wastewater in the pool; the generator 103 is used to concentrate the heated wastewater entering; the absorption tower 104 is used to condense the hot and humid air discharged from the generator tower 103 to produce clean water; the regenerator 102 is used to heat the circulating wastewater of the generator tower 103 and cool the circulating clean water of the absorption tower 104; the fan 105 is used to realize the gas flow in the system; the recooler 106 is used to cool the gas discharged from the absorption tower 104 again; the gas-liquid separator 107 is used to separate the clean water and air obtained after cooling by the recooler 106.

[0034] The solar pond 101 is connected to the liquid inlet at the top of the generating tower 103, the air outlet at the top of the generating tower 103 is connected to the air inlet at the bottom of the absorbing tower 104 through a pipeline, and the air outlet at the top of the absorbing tower 104 is connected to the air inlet at the bottom of the generating tower 103 through a pipeline that passes through the subcooler 106 and the gas-liquid separator 107 in sequence.

[0035] The wastewater heated in the solar pond 101 enters the generating tower 103 from the liquid inlet of the generating tower 103 and contacts with the dry cold air entering from the bottom of the generating tower 103 in countercurrent. After the dry cold air is fully mixed with the hot wastewater, the moist hot air is discharged from the top of the generating tower 103. The moist hot air enters the absorption tower 104 from the bottom of the absorption tower 104 and mixes with the cooling clean water sprayed downward from the top of the absorption tower 104 in countercurrent. After the moist hot air is cooled, the water vapor carried therein condenses into water and stays in the absorption tower 104. The dehumidified air is discharged from the air outlet on the top of the absorption tower 104. After being cooled and dehumidified again by the recooler 106, the condensed clean water and air are separated under the action of the gas-liquid separator 107, the clean water is discharged, and the dehumidified dry cold air is circulated again and passed into the lower part of the generating tower 103.

[0036] The lower part of the generating tower 103 is provided with a circulating waste liquid outlet, which is connected to the liquid inlet at the upper part of the generating tower 103 through a pipeline passing through the regenerator 102. The circulating waste liquid passing through the regenerator 102 provides a cold source for the regenerator 102.

[0037] The lower part of the absorption tower 104 is provided with a circulating clean water outlet, which is connected to the liquid inlet at the upper part of the absorption tower 104 through a pipeline passing through the regenerator 102 . The circulating clean water passing through the regenerator 102 provides a heat source for the regenerator 102 .

[0038] The regenerator 102 is used to make the circulating clean water provide heat for the circulating waste liquid, thereby achieving the purpose of lowering the temperature of the circulating clean water and heating the circulating waste liquid, so that the heat is reasonably utilized.

[0039] Optionally, a waste liquid circulation pump is provided on the pipeline connecting the circulating waste liquid outlet with the liquid inlet at the upper part of the generating tower 103, and the waste liquid at the bottom of the tower is circulated to the top of the tower through the waste liquid circulation pump.

[0040] Optionally, a clean water circulation pump is provided on the pipeline connecting the circulating clean water outlet with the liquid inlet at the top of the absorption tower 104, and the clean water at the bottom of the tower is circulated to the top of the tower through the clean water circulation pump.

[0041] The fan 105 is arranged on the pipeline between the gas outlet at the top of the generating tower 103 and the gas inlet at the bottom of the absorbing tower 104. The arrangement of the fan 105 enables the gas in the system to circulate.

[0042] Optionally, a cooler 108 is further provided between the regenerator 102 and the liquid inlet at the upper portion of the absorption tower 104 .

[0043] The circulating purified water cooled by the regenerator 102 may still have a relatively high heat content. The cooler 108 is provided to cool the circulating purified water again, so that the circulating purified water entering the absorption tower 104 again can have a more efficient condensation effect on the hot and humid air.

[0044] Optionally, a clean water discharge pipe 109 is connected to the pipeline between the cooler 108 and the regenerator 102 .

[0045] Since the condensed clean water all comes from the wastewater entering the generating tower 103, the clean water in the system is constantly increasing. By discharging part of the clean water from the clean water discharge pipe 109, the clean water in the system is maintained within an appropriate content range.

[0046] Optionally, the open evaporative absorption wastewater purification device also includes a liquid storage tank 110, which is arranged on a pipe connecting the liquid inlet of the generating tower 103 and the circulating waste liquid outlet, and the liquid storage tank 110 is located between the liquid inlet of the generating tower 103 and the regenerator 102. At the same time, the liquid storage tank 110 is also located on the pipe between the solar pool 101 and the liquid inlet at the top of the generating tower 103.

[0047] The liquid storage tank 110 is used to store the wastewater heated by the solar pond 101 and the wastewater heated by the regenerator 102 , and continuously input the wastewater into the generating tower 103 .

[0048] Optionally, a first nozzle 111 for downward spraying connected to a liquid inlet of the generating tower 103 is provided at the top of the generating tower 103 , and a first demister 112 is further provided between the first nozzle 111 and a gas outlet of the generating tower 103 .

[0049] The first nozzle 111 is used to spray the wastewater entering the generating tower 103 from top to bottom, thereby improving the heat transfer effect between the wastewater and the incoming air. The first demister 112 is mainly composed of plates and supporting devices, which belong to the prior art and will not be described in detail here. The purpose of setting the first demister 112 is to capture large particle droplets during the spraying process to prevent wastewater droplets from entering the gas pipeline and causing pipeline corrosion and other problems.

[0050] Optionally, a second nozzle 113 for downward spraying connected to the liquid inlet of the absorption tower 104 is provided at the top of the absorption tower 104 , and a second demister 114 is further provided between the second nozzle 113 and the gas outlet of the absorption tower 104 .

[0051] The second nozzle 113 is used to spray the clean water entering the absorption tower 104 from top to bottom, thereby improving the heat transfer effect between the clean water and the incoming hot and humid air. The second demister 114 is mainly composed of plates and supporting devices, which belong to the prior art and will not be described in detail here. The purpose of setting the second demister 114 is to capture large particles of water droplets during the spraying process to prevent the droplets from entering the gas pipeline.

[0052] The discharge port of the drug adding box 115 is connected to the opening of the clarification barrel 116 , the bottom waste residue discharge port of the clarification barrel 116 is connected to the filter press 117 , and the middle of the clarification barrel 116 is connected to the solar pond 101 .

[0053] The dosing box 115 is filled with drugs that are helpful for purifying wastewater, such as sedimentation aids, and the dosing box 115 puts the drugs used for purifying wastewater into the clarification barrel 116, so that most of the pollutants in the wastewater in the clarification barrel 116 are settled, and the waste residue at the bottom enters the filter press 117 for filtration, and the filtration residue is sent to the waste residue pool 120 for unified treatment; the clean water on the upper part of the clarification barrel 116 is passed into the solar pool 101 for heating.

[0054] Optionally, a sewage pump is provided on the pipeline connecting the clarification tank 116 and the solar pond 101 , and the clear water in the clarification tank 116 is pumped into the solar pond 101 through the sewage pump.

[0055] Optionally, the open evaporation absorption sewage purification device also includes an agitator 118, the bottom waste residue discharge port of the clarification barrel 116 is connected to the agitator 118, and the agitator 118 is connected to the filter press 117; a waste residue discharge port is provided at the bottom of the generating tower 103, and the waste residue discharge port is connected to the agitator 118.

[0056] The waste residue (concentrated sewage) at the bottom of the generating tower 103 and the waste residue discharged from the clarification tank 116 are mixed in the agitator 118 and then sent to the filter press 117 for filtration.

[0057] Optionally, a waste residue pump is provided on the pipeline connecting the waste residue discharge outlet at the bottom of the generating tower 103 and the agitator 118 , and the waste residue is discharged into the agitator 118 through the waste residue pump.

[0058] Optionally, the discharge port of the filter press 117 is connected to the clarification tank 116, and the filtrate produced by the filter press 117 is sent to the clarification tank 116 again for treatment.

[0059] The process flow of the open evaporation absorption sewage purification device provided in this application is as follows:

[0060] (1) Waste liquid process:

[0061] The waste liquid is first introduced into the clarification barrel 116, and the solid-liquid separation is carried out under the action of the sedimentation aid in the dosing box 115. The clarified supernatant in the clarification barrel 116 is pumped into the solar pool 101 by a sewage pump for heating and temperature rise, and then introduced into the liquid storage tank 110. After that, the waste liquid in the liquid storage tank 110 enters the generating tower 103, and is sprayed and dripped by the nozzle, and directly contacts with the dry cold air in the tower, and the two transfer heat and mass. After the spraying, the waste liquid is cooled and reduced in volume and falls to the bottom of the tower. With the continuous spraying of the waste liquid, concentrated waste liquid will accumulate at the bottom of the generating tower 103. The concentrated waste liquid accumulated at the bottom of the tower is extracted by the solution pump, and after absorbing the clean water heat in the regenerator 102, it is introduced into the liquid storage tank 110, mixed with the waste liquid from the solar pool 101, and then introduced into the generating tower 103 for spraying again, and the waste liquid circulates back and forth.

[0062] (2) Water purification process:

[0063] The clean water is mainly sprayed and circulated in the absorption tower 104. The clean water at the bottom of the tower is cooled by the regenerator 102. A part of the cooled clean water is output as the product system, and the remaining clean water is further cooled by the cooler 108 and then enters the absorption tower 104. It is directly contacted with the hot and humid air through the nozzle to cool the hot and humid air. The condensed water produced by the cooling of the hot and humid air is added to the clean water circulation.

[0064] As hot and humid air is continuously introduced into the absorption tower 104, the moisture in the clean water circulation increases continuously, and a clean water discharge pipe 109 is arranged in front of the cooler 108 to output part of the clean water to the outside.

[0065] (3) Air flow:

[0066] After the air enters the lower part of the generating tower 103, it directly exchanges heat and mass with the concentrated waste liquid sprayed down, the temperature and moisture content increase, and the dry cold air is transformed into hot and humid air, which is discharged after passing through the defogger at the top of the generating tower 103; after the hot and humid air is discharged from the generating tower 103, it passes through the fan 105 and enters the lower part of the absorption tower 104, where it is sprayed with clean water in a circulating manner, and the temperature and moisture content are reduced. Thereafter, the air is defogged by the defogger at the top of the absorption tower 104, and then enters the recooler 106 for further cooling and dehumidification, and then passes into the gas-liquid separator 107. The clean water at the outlet of the gas-liquid separator 107 is output to the outside, and the outlet gas returns to the lower part of the generating tower 103 as dry and cold air, and the cycle is repeated.

[0067] (4) Waste slag process:

[0068] The waste residue deposited at the bottom of the clarification barrel 116 and the waste residue generated by the concentrated waste liquid accumulation at the bottom of the generating tower 103 are introduced into the agitator 118 together, and after being evenly stirred in the agitator 118, they are introduced into the filter press 117 and filtered under pressure with compressed air. The filtrate returns to the clarification barrel 116 for clarification, and the filter cake is transported to the waste residue pool 120 by the belt for storage.

[0069] In summary, the open evaporation sewage purification device for ammonia waste liquid provided by the embodiment of the utility model has the following characteristics:

[0070] 1. A large amount of pure water can be recovered from the ammonia waste liquid to achieve zero wastewater discharge.

[0071] 2. The waste liquid is heated by the solar pool 101 to heat cooling water or process water, thus realizing industrial waste heat recovery and utilization;

[0072] 3. Recycling of waste residues, transforming the traditional wet discharge method into a filter press dry discharge method. The waste residues produced can be used for land reclamation or as raw materials for building materials production.

[0073] 4. The provision of the recooler 106 and the gas-liquid separator 107 can enable the purified water to be collected more effectively, thereby improving the water recovery rate.

[0074] The embodiment of the utility model also provides an ammonia-soda process soda ash production system, including the open evaporation absorption sewage purification device provided by the embodiment of the utility model. Since the ammonia-soda process soda ash production system includes the open evaporation sewage purification device for ammonia waste liquid provided by the utility model, it can at least produce pure water and achieve the effect of zero wastewater discharge.

[0075] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An open evaporation wastewater purification device for ammonia waste liquid, characterized in that: It includes solar pool, regenerator, generator tower, absorption tower, fan, recooler, gas-liquid separator, dosing box, clarification tank and filter press; The solar pond is connected to the liquid inlet at the top of the generating tower, the gas outlet at the top of the generating tower is connected to the gas inlet at the bottom of the absorbing tower through a pipeline, and the gas outlet at the top of the absorbing tower is connected to the gas inlet at the bottom of the generating tower through a pipeline that passes through the subcooler and the gas-liquid separator in sequence; The lower part of the generating tower is provided with a circulating waste liquid outlet, 106 the circulating waste liquid outlet is connected to the liquid inlet at the upper part of the generating tower through a pipeline passing through the regenerator, and the circulating waste liquid passing through the regenerator provides a cold source for the regenerator; The lower part of the absorption tower is provided with a circulating clean water outlet, and the circulating clean water outlet is connected to the liquid inlet at the upper part of the absorption tower through a pipeline passing through the regenerator, and the circulating clean water passing through the regenerator provides a heat source for the regenerator; The fan is arranged on the pipeline between the air outlet at the top of the generating tower and the air inlet at the bottom of the absorbing tower; The drug discharge port of the drug adding box is communicated with the opening of the clarification barrel, the waste residue discharge port at the bottom of the clarification barrel is communicated with the filter press, and the middle part of the clarification barrel is communicated with the solar pond.

2. The open evaporation absorption sewage purification device according to claim 1 is characterized in that: A cooler is also provided between the regenerator and the liquid inlet at the upper portion of the absorption tower.

3. The open evaporation absorption sewage purification device according to claim 2 is characterized in that: A clean water discharge pipe is connected to the pipeline between the cooler and the regenerator.

4. The open evaporation absorption sewage purification device according to claim 1 is characterized in that: The open evaporative absorption wastewater purification device also includes a liquid storage tank, which is arranged on a pipeline connected between the liquid inlet of the generating tower and the circulating waste liquid outlet, and the liquid storage tank is located between the liquid inlet of the generating tower and the regenerator. At the same time, the liquid storage tank is also located on the pipeline between the solar pond and the liquid inlet on the upper part of the generating tower.

5. The open evaporation absorption sewage purification device according to claim 1 is characterized in that: The top of the generating tower is provided with a first nozzle connected with the liquid inlet of the generating tower for spraying downwards, and a first demister is also provided between the first nozzle and the gas outlet of the generating tower.

6. The open evaporation absorption sewage purification device according to claim 1 is characterized in that: The top of the absorption tower is provided with a second nozzle connected with the liquid inlet of the absorption tower for spraying downwards, and a second demister is also provided between the second nozzle and the gas outlet of the absorption tower.

7. The open evaporation absorption sewage purification device according to claim 1 is characterized in that: The open type evaporation absorption sewage purification device further comprises a stirrer, the waste residue discharge port at the bottom of the clarification barrel is connected to the stirrer, and the stirrer is connected to the filter press; A waste residue discharge port is provided at the bottom of the generating tower, and the waste residue discharge port is communicated with the agitator.

8. An ammonia-soda process soda ash production system, characterized in that: It comprises the open evaporation absorption sewage purification device as described in any one of claims 1 to 7.

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