Compressed air distribution device and tail end wastewater bypass flue evaporation system

Abstract

The invention relates to a compressed air distribution device and a tail end wastewater bypass flue evaporation system. The compressed air distribution device comprises a spray gun group, a control valve group and an air path distributor, one end of the air path distributor is connected with compressed air input equipment, a flow guide plate and a pressure balance cavity are arranged in the air path distributor, the flow guide plate is used for conducting angle optimization on input compressed air, and the pressure balance cavity is used for distributing the compressed air optimized by the flow guide plate into all the cavities in a balanced mode. The hoses are connected with the spray guns in the spray gun group in a one-to-one correspondence manner; one end of the waterway distributor is connected with a desulfurization wastewater pipeline and is connected with the corresponding spray gun through a pipeline; and the control valve group is distributed in a hose connected with the gas path distributor and a pipeline connected with the water path distributor. Compared with the prior art, the system has the advantages that the stability is improved, the energy consumption is reduced, and equipment protection and automatic control are realized.

Description

Technical Field

[0001] This invention relates to the field of wastewater treatment technology, and in particular to a compressed air distribution device and a terminal wastewater bypass flue evaporation system. Background Technology

[0002] High-salinity wastewater treatment commonly employs steam compression condensation or biochemical treatment, but these methods suffer from drawbacks such as high cost, high energy consumption, and susceptibility to microbial inhibition.

[0003] Two-phase flow processes achieve solid-liquid separation by atomizing wastewater with compressed air. For example, the invention disclosed in publication number CN111747588A describes a two-fluid atomization device in a full-load continuous flue gas evaporation zero-emission treatment process for high-flow, high-salt wastewater. However, existing air circuit systems suffer from unstable compressed air and uneven flow, leading to increased equipment wear, poor atomization effect, and reduced wastewater zero-emission efficiency.

[0004] The existing two-phase flow process has the following drawbacks: 1. Fluctuations in compressed air cause unstable atomization of the spray gun, leading to scaling and corrosion on the inner wall of the drying tower.

[0005] 2. Insufficient gas path control precision results in a mismatch between flue gas flow and spray volume, leading to low system reliability (e.g., existing equipment uptime <90%). Summary of the Invention

[0006] The purpose of this invention is to overcome the defects of the prior art, such as unstable atomization effect of spray gun caused by compressed air fluctuation and insufficient air path control accuracy, and to provide a compressed air distribution device and a terminal wastewater bypass flue evaporation system.

[0007] The objective of this invention can be achieved through the following technical solutions: A compressed air distribution device is installed in a spray dryer and connected to a water distributor. The spray dryer has a flue gas passage. The device includes a spray gun assembly, a control valve assembly, and an air distributor. One end of the air distributor is connected to a compressed air input device. The air distributor has a guide plate and a pressure balancing chamber inside. The guide plate is used to optimize the angle of the input compressed air, and the pressure balancing chamber is used to evenly distribute the optimized compressed air to each chamber. Then, it is connected to each spray gun in the spray gun assembly through a hose. One end of the water distributor is connected to a desulfurization wastewater pipeline, and is connected to the corresponding spray gun through the pipeline. The control valve assembly is distributed in the hose connected to the gas distributor and the pipeline connected to the water distributor.

[0008] Furthermore, the control valve assembly includes a pressure sensor and an electric regulating valve installed in the hose connected to each air distributor and the pipeline connected to each water distributor, for monitoring the corresponding air or water pressure and dynamically adjusting the flow rate.

[0009] Furthermore, the flue gas passage of the spray dryer is equipped with a flue gas temperature sensor and a flue gas flow sensor to monitor the flue gas temperature and flow rate; The control valve assembly is also used to adjust the air intake of the hoses connected to each nozzle according to the monitored flue gas temperature and flow rate.

[0010] Furthermore, the control valve assembly is connected to a PLC system and is controlled by the PLC system; both the flue gas temperature sensor and the flue gas flow sensor are connected to the PLC system.

[0011] Furthermore, a temperature sensor is provided at the outlet end of the spray dryer to measure the outlet temperature of the spray dryer, and the temperature sensor is connected to the PLC system; The PLC system adjusts the airflow of each hose according to the outlet temperature of the spray dryer.

[0012] The control process of the PLC system includes: The upper limit setting value of the spray flow rate of the spray gun is determined based on the real-time monitored flue gas temperature. The minimum setting value of the spray flow rate of the spray gun is obtained by dividing the total amount of desulfurization wastewater to be treated by the number of spray guns in operation and the corresponding operation and treatment time. The desulfurization wastewater flow rate of the compressed air distribution device is compared with the upper limit setting value of the spray flow rate in real time to determine the adjustment amount. It is also compared with the lower limit setting value of the spray flow rate of the spray gun to ensure that the adjustment amount of the output control valve group is between the upper limit setting value and the lower limit setting value of the spray flow rate.

[0013] Furthermore, the guide vane is a 270° spiral guide vane.

[0014] Furthermore, the spray gun assembly is provided with three spray guns, and the pressure balancing chamber in the air distribution unit has a circular cross-section, including three pressure balancing sub-chambers. The cross-section of each pressure balancing sub-chamber is a fan-shaped structure with an angle of 120 degrees. The three pressure balancing sub-chambers are spliced ​​together to form the pressure balancing chamber.

[0015] Furthermore, the input end of the spray gun is connected to the hose connected to the air distributor and the pipeline connected to the water distributor, respectively.

[0016] The present invention also provides an end-of-pipe wastewater bypass flue gas evaporation system, including a spray dryer, a compressed air distribution device as described above, a flue gas distributor, an air compressor, a boiler, and an electrostatic precipitator. The output end of the air compressor is connected to the air distributor, the flue gas output from the boiler is connected to the flue gas distributor, the flue gas distributor is connected to the spray dryer, the compressed air distribution device is located inside the spray dryer and is connected to a desulfurization wastewater pipeline, and the output end of the spray dryer is connected to the electrostatic precipitator.

[0017] Furthermore, after being filtered and dried by the air compressor, the compressed air enters the air distributor in the compressed air distribution device. It is evenly distributed to each pressure balance chamber by the guide plate and then connected to the spray gun group. The flue gas generated by the boiler is injected into the spray dryer. The water distributor connected to the compressed air distribution device is injected with desulfurization wastewater and connected to the spray gun group. Based on the flue gas temperature and flow rate, the air intake of each spray gun in the spray gun group is adjusted by the control valve group to ensure that the atomized desulfurization wastewater is fully mixed and evaporated with the flue gas; the output gas of the spray dryer is treated by the electrostatic precipitator.

[0018] Compared with the prior art, the present invention has the following advantages: (1) The present invention specifically sets up an air path distributor to optimize compressed air. The air path distributor first optimizes the angle through a guide plate, and then reduces the fluctuation amplitude of compressed air through the design of a pressure balance chamber, so that the fluctuation amplitude of compressed air is reduced from ±15% to ±5%, the atomization uniformity is improved by 30%, the system operation reliability is ≥95%, and the annual failure time is <5%; Furthermore, control valve groups are added to the hoses connected to the air distributor and the pipelines connected to the water distributor. These valves can be linked with the PLC system to automatically adjust the air flow of each branch based on the drying tower outlet temperature signal (such as a set value of 120℃±5℃), thereby achieving precise matching between the atomization amount and the flue gas volume.

[0019] (2) Reduced energy consumption: The present invention optimizes the angle of compressed air by means of a guide plate and distributes it evenly to each pressure balance chamber, reducing air resistance by 20% and reducing air compressor energy consumption by about 12%, saving more than 150,000 yuan in annual operating costs.

[0020] (3) Equipment protection: The present invention automatically adjusts the air intake of each spray gun by controlling the valve group according to the real-time monitoring of flue gas temperature and flow data, ensuring that the atomized wastewater and flue gas are fully mixed and evaporated, avoiding the tower wall from getting wet and scaling; the uniform airflow also reduces the wear of the spray gun and the inner wall of the drying tower, extending the service life of the equipment to more than 8 years (originally 5 years).

[0021] (4) Automated control: Through the systematic setting of various pressure sensors, temperature sensors, electric regulating valves and PLC, the entire process can be unattended, reducing operating costs by 40%.

[0022] (5) In the PLC system control logic of the present invention, the upper limit setting value of the spray flow rate is automatically calculated based on the temperature value of the flue gas at the outlet of the drying tower, and the lower limit setting value of the spray flow rate is automatically calculated based on the water volume in the wastewater tank. The wastewater spray volume is dynamically adjusted through dual limits. When the operating conditions change, there is no need to adjust the number of spray guns in operation, resulting in less disturbance and more uniform heating of the drying tower, which can achieve a higher spray effect. It can also prevent the outlet flue gas temperature from falling below the guaranteed value due to excessive water volume, which would affect the operation effect of the subsequent electrostatic precipitator. While ensuring the stable operation of the unit with zero wastewater discharge at the end, it also greatly reduces the workload of the operators. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the structure of an end-of-pipe wastewater bypass flue evaporation system provided in an embodiment of the present invention; Figure 2 This is a schematic diagram of a compressed air distribution device provided in an embodiment of the present invention; Figure 3 This is a schematic diagram of a gas distributor provided in an embodiment of the present invention; Figure 4 This is a schematic diagram of the control logic of a PLC system provided in an embodiment of the present invention; In the diagram, 1 is a spray dryer, 2 is a compressed air distribution device, 201 is a spray gun assembly, 202 is a control valve assembly, 203 is an air distributor, 3 is a flue gas distributor, 4 is an air compressor, 5 is an electrostatic precipitator, 6 is a desulfurization wastewater pipeline, 7 is compressed air, and 8 is a boiler. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0025] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0026] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0027] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the product of this invention is usually placed during use. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0028] It should be noted that the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0029] Furthermore, terms such as "horizontal" and "vertical" do not imply that components must be absolutely horizontal or suspended, but rather that they can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," not that the structure must be completely horizontal, but can be slightly tilted.

[0030] Example 1 like Figure 1 and Figure 2 As shown, this embodiment provides a compressed air distribution device, which is installed in a spray dryer 1 and connected to a water distributor. The spray dryer 1 has a flue gas passage. The device includes: a spray gun assembly 201, a control valve assembly 202, and an air distributor 203. One end of the air distributor 203 is connected to a compressed air 7 input device. It has a guide plate and a pressure balance chamber inside. The guide plate is used to optimize the angle of the input compressed air 7, and the pressure balance chamber is used to distribute the compressed air 7 optimized by the guide plate to each chamber in a balanced manner. Then, it is connected to each spray gun in the spray gun assembly 201 through a hose. One end of the water distributor is connected to the desulfurization wastewater pipe 6, and is connected to the corresponding spray gun through the pipe; The control valve assembly 202 is distributed in the hose connected to the gas distributor 203 and the pipeline connected to the water distributor.

[0031] This solution uses a dedicated air distributor 203 to optimize the compressed air 7. The air distributor 203 first optimizes the angle of the air through a guide plate, and then reduces the fluctuation amplitude of the compressed air 7 through the design of a pressure balance chamber. This reduces the fluctuation amplitude of the compressed air 7 from ±15% to ±5%, improves the atomization uniformity by 30%, and achieves system operational reliability ≥95% and annual downtime <5%. Furthermore, a control valve group 202 is added to the hose connected to the air distributor 203 and the pipeline connected to the water distributor. It can be linked with the PLC system to automatically adjust the air flow of each branch according to the drying tower outlet temperature signal (such as the set value of 120℃±5℃) to achieve precise matching between atomization amount and flue gas volume.

[0032] Preferably, the control valve assembly 202 includes a pressure sensor and an electric regulating valve disposed in the hose connected to each air distributor 203 and the pipeline connected to each water distributor, for monitoring the corresponding air or water pressure and dynamically adjusting the flow rate.

[0033] That is, by integrating a pressure sensor and an electric regulating valve into the control valve assembly 202, the gas pressure is monitored in real time and the flow rate is dynamically adjusted.

[0034] Preferably, the flue gas passage of the spray dryer 1 is equipped with a flue gas temperature sensor and a flue gas flow sensor to monitor the flue gas temperature and flow rate; The control valve assembly 202 is also used to adjust the air intake of the hoses connected to each nozzle according to the monitored flue gas temperature and flow rate.

[0035] Preferably, the control valve assembly 202 is connected to a PLC system and is controlled by the PLC system, and both the flue gas temperature sensor and the flue gas flow sensor are connected to the PLC system.

[0036] A temperature sensor is installed at the outlet of spray dryer 1 to measure the outlet temperature of spray dryer 1. The temperature sensor is connected to the PLC system. The PLC system adjusts the airflow of each hose according to the outlet temperature of spray dryer 1.

[0037] like Figure 4 As shown, the control process of the PLC system includes: The upper limit setting value of the spray flow rate of the spray gun is determined based on the real-time monitored flue gas temperature. The minimum setting value of the spray flow rate of the spray gun is obtained by dividing the total amount of desulfurization wastewater to be treated by the number of spray guns in the spray gun group 201 and the corresponding operation and treatment time. The desulfurization wastewater flow rate of the compressed air distribution device is compared with the upper limit setting value of the spray flow rate to determine the adjustment amount, and compared with the lower limit setting value of the spray flow rate of the spray gun to ensure that the adjustment amount of the output control valve group 202 is between the upper limit setting value and the lower limit setting value of the spray flow rate.

[0038] Specifically, in this embodiment, the upper limit setting value of the wastewater spray flow rate is set proportionally to the outlet flue gas temperature of the drying tower, as shown in Table 1: Table 1 Automatic low limit setting is performed based on the water volume in the terminal water tank and the number of spray guns in operation, with a 24-hour timeframe: Wastewater spray flow rate minimum setting (T / h) = Q (total wastewater) / (N (number of spray guns in operation) * 24h) In the PLC system control logic of this embodiment, the upper limit setting value of the spray flow rate is automatically calculated based on the temperature value of the flue gas at the outlet of the drying tower, and the lower limit setting value of the spray flow rate is automatically calculated based on the water volume in the wastewater tank. The wastewater spray volume is dynamically adjusted through dual limits. When the operating conditions change, there is no need to adjust the number of spray guns in operation, resulting in less disturbance and more uniform heating of the drying tower, which can achieve a higher spraying effect.

[0039] It can also prevent the outlet flue gas temperature from falling below the guaranteed value due to excessive water volume, thus affecting the subsequent operation of the electrostatic precipitator. While ensuring the stable operation of the unit with zero wastewater discharge at the end, it also greatly reduces the workload of the operators.

[0040] This achieves intelligent control: the control valve group is linked with the PLC system, and automatically adjusts the air flow of each branch according to the drying tower outlet temperature signal, such as the set value of 120℃±5℃, to achieve precise matching between atomization amount and flue gas volume.

[0041] Preferably, the guide vane is a 270° spiral guide vane.

[0042] A 270° spiral flow guide structure is a device used inside pipes, elbows, or equipment inlets / outlets. Its core purpose is to guide fluid gas or liquid from a straight flow to a rotating flow smoothly. However, the rotation angle is not a full 360°, but three-quarters of it, namely 270°.

[0043] Optional, such as Figure 3 As shown, the spray gun assembly 201 is equipped with three spray guns. The pressure balancing chamber in the air distribution unit 203 has a circular cross-section and includes three pressure balancing sub-chambers. The cross-section of each pressure balancing sub-chamber is a fan-shaped structure with an angle of 120 degrees. The three pressure balancing sub-chambers are spliced ​​together to form the pressure balancing chamber.

[0044] By optimizing the angle of the guide vane, such as the 270° spiral guide and the pressure balance chamber design, the fluctuation range of compressed air is reduced to within ±5%.

[0045] The spray gun's input end is connected to the hose connected to the air distributor 203 and the pipeline connected to the water distributor, respectively.

[0046] In this embodiment, the guide plate adopts a 270° spiral guide structure with a spiral lead of 100mm, a plate thickness of 5mm, and is made of 304 stainless steel. The total volume of the pressure balancing chamber is 5L, the volume of a single sector-shaped sub-chamber is 1.67L, and the wall thickness is 8mm. The connecting hose has a diameter of Ф50mm, a length of 2m, and a pressure resistance of 1.6MPa.

[0047] like Figure 1 As shown, this embodiment also provides an end-of-pipe wastewater bypass flue gas evaporation system, including a spray dryer 1, a compressed air distribution device 2 as described above, a flue gas distributor 3, an air compressor 4, a boiler 8, and an electrostatic precipitator 5. The output end of the air compressor 4 is connected to the air distribution device 203, the flue gas output from the boiler 8 is connected to the flue gas distributor 3, the flue gas distributor 3 is connected to the spray dryer 1, the compressed air distribution device 2 is located inside the spray dryer 1 and is connected to a desulfurization wastewater pipeline 6, and the output end of the spray dryer 1 is connected to the electrostatic precipitator 5.

[0048] Working principle: Compressed air 7 is filtered and dried by air compressor 4 and then enters the air distributor 203 in compressed air distribution device 2. It is evenly distributed to each pressure balance chamber by the guide plate and then connected to the spray gun group 201. The flue gas generated by the boiler is injected into the spray dryer 1. The water distributor connected to compressed air distribution device 2 is injected with desulfurization wastewater and connected to spray gun group 201. Based on the flue gas temperature and flow rate, the air intake of each spray gun in the spray gun group 201 is adjusted by the control valve group 202 so that the atomized desulfurization wastewater and flue gas are fully mixed and evaporated; the output gas of the spray dryer 1 is treated by the electrostatic precipitator 5.

[0049] Essentially, compressed air is filtered and dried by an air compressor before entering the air manifold. It is then evenly distributed to each branch via a guide plate, and the pressure balance chamber eliminates airflow pulses. The control valve group automatically adjusts the air intake of each spray gun based on real-time monitoring of flue gas temperature and flow data to ensure that the atomized wastewater and flue gas are fully mixed and evaporated, thus avoiding wet walls and scaling on the tower.

[0050] The preferred embodiments of the present invention have been described in detail above. It should be understood that those skilled in the art can make numerous modifications and variations based on the concept of the present invention without creative effort. Therefore, all technical solutions that can be obtained by those skilled in the art based on the concept of the present invention through logical analysis, reasoning, or limited experimentation on the basis of existing technology should be within the scope of protection defined by the claims.

Claims

1. A compressed air distribution device, installed in a spray dryer (1) and connected to a water distributor, wherein the spray dryer (1) has a flue gas passage, characterized in that, The device includes: a spray gun assembly (201), a control valve assembly (202), and an air distributor (203); one end of the air distributor (203) is connected to a compressed air (7) input device, and a guide plate and a pressure balance chamber are provided inside. The guide plate is used to optimize the angle of the input compressed air (7), and the pressure balance chamber is used to balance the compressed air (7) optimized by the guide plate and distribute it to each chamber. Then, it is connected to each spray gun in the spray gun assembly (201) one by one through a hose. One end of the water distributor is connected to a desulfurization wastewater pipe (6), and is connected to the corresponding spray gun through the pipe. The control valve assembly (202) is distributed in the hose connected to the gas distributor (203) and the pipeline connected to the water distributor.

2. The compressed air distribution device according to claim 1, characterized in that, The control valve group (202) includes a pressure sensor and an electric regulating valve installed in the hose connected to each air distributor (203) and the pipeline connected to each water distributor, for monitoring the corresponding air or water pressure and dynamically adjusting the flow rate.

3. A compressed air distribution device according to claim 2, characterized in that, The spray dryer (1) is equipped with a flue gas temperature sensor and a flue gas flow sensor in the flue gas passage for monitoring flue gas temperature and flow rate; The control valve assembly (202) is also used to adjust the air intake of the hoses connected to each nozzle according to the monitored flue gas temperature and flow rate.

4. A compressed air distribution device according to claim 3, characterized in that, The control valve group (202) is connected to a PLC system and is controlled by the PLC system. The flue gas temperature sensor and the flue gas flow sensor are both connected to the PLC system. The spray dryer (1) is equipped with a temperature sensor at its outlet end for measuring the outlet temperature of the spray dryer (1), and the temperature sensor is connected to the PLC system. The PLC system adjusts the airflow of each hose according to the outlet temperature of the spray dryer (1).

5. A compressed air distribution device according to claim 4, characterized in that, The control process of the PLC system includes: The upper limit setting of the spray flow rate of the spray gun is determined based on the real-time monitored flue gas temperature. The minimum setting value of the spray flow rate of the spray gun is obtained by dividing the total amount of desulfurization wastewater to be treated by the number of spray guns in operation and the corresponding operation and treatment time in the spray gun group (201). The desulfurization wastewater flow rate of the compressed air distribution device is obtained in real time and compared with the upper limit setting value of the spray flow rate to determine the adjustment amount. It is also compared with the lower limit setting value of the spray flow rate of the spray gun to ensure that the adjustment amount of the output control valve group (202) is between the upper limit setting value and the lower limit setting value of the spray flow rate.

6. A compressed air distribution device according to claim 1, characterized in that, The guide plate is a 270° spiral guide plate.

7. A compressed air distribution device according to claim 1, characterized in that, The spray gun assembly (201) is provided with three spray guns. The pressure balance chamber in the air distribution unit (203) has a circular cross-section and includes three pressure balance sub-chambers. The cross-section of each pressure balance sub-chamber is a fan-shaped shape with an angle of 120 degrees. The three pressure balance sub-chambers are spliced ​​together to form the pressure balance chamber.

8. A compressed air distribution device according to claim 1, characterized in that, The input end of the spray gun is connected to the hose connected to the air distributor (203) and the pipeline connected to the water distributor.

9. A terminal wastewater bypass flue gas evaporation system, characterized in that, The device includes a spray dryer (1), a compressed air distribution device (2) as described in any one of claims 1-8, a flue gas distributor (3), an air compressor (4), a boiler (8), and an electrostatic precipitator (5). The output end of the air compressor (4) is connected to the air distributor (203). The flue gas output from the boiler (8) is connected to the flue gas distributor (3). The flue gas distributor (3) is connected to the spray dryer (1). The compressed air distribution device (2) is located inside the spray dryer (1) and is connected to a desulfurization wastewater pipe (6). The output end of the spray dryer (1) is connected to the electrostatic precipitator (5).

10. The terminal wastewater bypass flue gas evaporation system according to claim 9, characterized in that, Compressed air (7) is filtered and dried by air compressor (4) and then enters the air distributor (203) in compressed air distribution device (2). It is evenly distributed to each pressure balance chamber by guide plate and then connected to spray gun group (201). The flue gas generated by the boiler (8) is injected into spray dryer (1). The water distributor connected to compressed air distribution device (2) is injected with desulfurization wastewater and connected to spray gun group (201). Based on the flue gas temperature and flow rate, the air intake of each spray gun in the spray gun group (201) is adjusted by the control valve group (202) so that the atomized desulfurization wastewater and flue gas are fully mixed and evaporated; the output gas of the spray dryer (1) is treated by the electrostatic precipitator (5).

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