Escape ammonia deep recovery device

Abstract

The invention relates to the field of industrial waste gas purification, environmental protection and energy, and discloses a device for deeply recovering escaped ammonia. According to the device, through respective independent double-channel design of'heating medium conduction and composite cooling ', high-temperature flue gas (100-120 DEG C) is rapidly cooled to a temperature below a dew point (45-95 DEG C), escaped ammonia is dissolved in water separated from the flue gas by utilizing the characteristic that ammonia gas is easily dissolved in water, the ammonia escape concentration is reduced to be below 10 mg / m from 800-15 mg / m, and the environmental protection requirement is met. The composite cooling technology comprises three stages of air cooling, water cooling and phase change heat transfer, and the cooling efficiency per unit water volume is improved by 3-5 times. Meanwhile, an intelligent control system is arranged, the dew point temperature (+ / -0.5 DEG C precision) is dynamically tracked, the spraying amount (the flow control precision is + / -2%) is adaptively adjusted, and stable operation of the device is ensured. The problems that a traditional low-temperature SCR technology is high in investment, large in energy consumption, insufficient in ammonia recovery rate under complex working conditions and the like are solved.

Description

Technical Field

[0001] The present invention relates to the fields of industrial waste gas purification, environmental protection and energy, and particularly to a device for deep recovery of escaped ammonia. Background Art

[0002] In industrial fields such as power plants and cement production, SNCR (Selective Non-Catalytic Reduction) and SCR (Selective Catalytic Reduction) technologies generally use urea or ammonia water as ammonia removal agents, but there is a dilemma in controlling the ammonia injection amount: when the dosage is insufficient, the removal effect of nitrogen oxides (NOx) is poor, and when it is excessive, the unreacted ammonia (NH3) enters the downstream equipment along with the flue gas. The escaped ammonia not only directly discharges into the atmosphere through the chimney, causing secondary pollution, but also reacts with sulfur dioxide (SO2) in the flue gas to generate highly corrosive ammonium bisulfate (NH4HSO4) and ammonium sulfate ((NH4)2SO4), accelerating the corrosion and blockage of desulfurization towers, dust removal equipment and SCR catalysts, resulting in shortened equipment life and soaring operation and maintenance costs. From the perspective of environment and health, ammonia emissions not only exacerbate air pollution, but may also form PM2.5 precursors, and its pungent smell and potential toxicity pose a threat to the health of surrounding residents, which makes the efficient treatment of escaped ammonia an urgent technical bottleneck to be broken through in the industry.

[0003] In the prior art, although the ammonia injection strategy can be optimized (such as closed-loop control based on CEMS) to reduce excessive ammonia injection, in complex working conditions with high humidity (for example, the humidity of the flue gas at the cement kiln tail is still up to 20% after drying), high dust or fluctuating flue gas components, the control accuracy drops significantly. Taking cement production as an example, the high-humidity environment reduces the activity of the SCR catalyst by more than 50%, and the ammonia escape concentration generally exceeds 25 mg / m³, far exceeding the environmental protection limit (≤10 mg / m³). In addition, there are obvious defects in the end-treatment technologies for escaped ammonia: although the low-temperature SCR technology can co-remove part of the ammonia, the equipment investment is high (more than 20 million to 30 million yuan per single line). In particular, the low-temperature SCR technology has poor adaptability to high-humidity flue gas and will cause catalyst poisoning when the flue gas temperature is higher than 100°C and cannot be used continuously, and the ammonia recovery rate is only 50%-60%; Patent CN202020952630.X proposes to set up a multi-stage spraying device in the flue, and the atomized ammonia removal agent reacts with the escaped ammonia to generate nitrogen and water. Although this technology does not require large-scale equipment, in a complex working condition environment with high humidity and high dust, the mixing efficiency of the ammonia removal agent and the flue gas is limited, and the reaction conditions are difficult to stably control, and the actual removal effect fluctuates significantly.

[0004] Therefore, there is an urgent need to develop a solution suitable for complex working conditions. Summary of the Invention

[0005] To overcome the problems in the prior art such as high equipment investment, low ammonia recovery rate, unstable reaction conditions, and significant fluctuations in removal effect, the present invention provides an ammonia slip deep recovery device, aiming to achieve precise treatment of ammonia slip under complex working conditions through an integrated design of efficient heat transfer, intelligent control, and resource recovery.

[0006] The technical solution adopted to achieve the above object is: an ammonia slip deep recovery device, comprising: a) A smoke flow sealing cavity and a cooling cavity that are independent of each other. The top of the smoke flow sealing cavity is provided with a smoke inlet, the lower side wall is provided with a smoke outlet, and the bottom is provided with a condensate discharge outlet. The lower side wall of the cooling cavity is provided with an air inlet, and the top is provided with an air outlet; b) A heat transfer component, mainly composed of an evaporation unit and a condensation unit, forming a closed vacuum structure. The vacuum degree inside the heat transfer component is 10 -4 -10 -1 Pa. The evaporation unit is internally provided with a heat medium and is arranged inside the smoke flow sealing cavity, and the condensation unit is arranged inside the cooling cavity; c) A water circulation system, including a water tank arranged at the bottom or below the cooling cavity, a water pump connected to the water tank in sequence through a pipeline, and a spray device at the top of the condensation unit; d) An axial flow fan or an induced draft fan arranged at the air outlet.

[0007] Further, the installation elevation of the evaporation unit is lower than that of the condensation unit.

[0008] Further, the outer surface of the evaporation unit is provided with an anti-corrosion coating.

[0009] Further, the filling amount of the heat medium in the heat transfer component is 5%-100% of the volume of the evaporation unit.

[0010] Further, a spray device is also provided in the upper part of the smoke flow sealing cavity.

[0011] Further, a demisting device is provided at the smoke outlet.

[0012] Further, the water tank is provided with a make-up water pipeline, a dosing device, and a sewage pipeline.

[0013] Further, the make-up water pipeline, the dosing device, the sewage pipeline, and the spray device are all provided with automatic control devices.

[0014] Further, the axial flow fan or the induced draft fan and the water pump are provided with frequency conversion control devices.

[0015] Furthermore, it also includes an intelligent control system, which comprises: an online ammonia concentration analyzer and an online flue gas component analyzer disposed in the flue gas circulation sealed cavity, temperature sensors disposed on the heat exchange surfaces of the evaporation unit and the condensation unit, temperature sensors, water level sensors, water quality monitoring probes and a PLC controller disposed in the water tank; the PLC controller serves as the core control module, and dynamically adjusts the fan speed, the spray water volume and the spray pressure based on the temperature difference of the condensation unit, the real-time ammonia concentration and the flue gas component data, and in combination with the dew point temperature obtained by converting the flue gas components; the PLC controller controls the start and stop of the spray device according to the real-time feedback of the ammonia concentration and the water vapor content in the flue gas; the PLC controller also controls the valves to perform water replenishment, chemical addition and sewage discharge operations by analyzing the temperature, water level and water quality monitoring results in the water tank.

[0016] The beneficial effects of the present invention are as follows: 1. Adaptability to complex working conditions: Aiming at the complex working conditions of high humidity (humidity up to 20% after drying), high dust and fluctuating flue gas components in power plants and cement production, based on the characteristic that ammonia is easily soluble in water, this device adopts the physical condensation phase change technology to cool the flue gas below the dew point (45 - 95 °C), so that the escaped ammonia is fully dissolved in the condensed water, and the removal efficiency is not affected by the flue gas fluctuation. The ammonia escape concentration can be stably reduced from 800 - 15 mg / m³ to below 10 mg / m³.

[0017] 2. Independent dual-channel heat medium circulation: Through the closed circulation of the high-efficiency heat medium in the sealed cavity, physical isolation between the flue gas and the cooling end is achieved, completely avoiding fouling and efficiency decay.

[0018] 3. Three-stage composite cooling technology: The water circulation system sprays water on the condensation unit through the spray device to form a water film on the surface of the condensation unit. Through heat transfer by water flow and heat transfer by water evaporation phase change, enhanced cooling of the condensation unit is implemented. In cooperation with the air convection in the cooling sealed cavity and the phase change (or convection) heat transfer of the heat medium in the heat transfer component, a trinity composite cooling system acts synergistically, increasing the cooling efficiency per unit water volume by 3 - 5 times and reducing the system energy consumption by 60%.

[0019] 4. Intelligent dynamic control: Integrating dynamic tracking of dew point temperature (accuracy ±0.5 °C), online monitoring of ammonia concentration (resolution 0.1 mg / m³), adaptive spray adjustment system (flow control accuracy ±2%) and flue gas component analysis, the PLC controller adjusts the fan speed, the coolant spray volume and pressure, and the spray volume of the water mist in real time to ensure that the condensation phase change process is accurately controllable, and the ammonia removal efficiency volatility < 5%.

[0020] 5. Modular and resource-based design: The adoption of modular design can significantly reduce the on-site installation cycle. Without the need for large-scale water circulation facilities, the ammonia-containing condensate can be deammoniated and then the concentrated ammonia water and reclaimed intermediate water can be recycled, achieving multiple goals of "quick installation - environmental compliance - resource recovery - cost savings".

[0021] 6. Environmental protection synergy: The fully enclosed design realizes the recovery of ammonia escape and also recovers the remaining NOx and SOx in the flue gas, meeting the increasingly stringent environmental protection requirements. Description of the Drawings

[0022] Figure 1 is the front view of Embodiment 1 of the present invention.

[0023] Figure 2 is the right view of Embodiment 1 of the present invention.

[0024] Figure 3 is the three-dimensional schematic diagram of the appearance of Embodiment 1 of the present invention.

[0025] Figure 4 is the front view of Embodiment 2 of the present invention.

[0026] Reference numerals: 1 - Flue gas flow sealing cavity; 2 - Cooling cavity; 3 - Flue gas inlet; 4 - Flue gas outlet; 5 - Condensate discharge outlet; 6 - Air inlet; 7 - Air outlet; 8 - Evaporation unit; 9 - Condensation unit; 10 - Water tank; 11 - Pipeline; 12 - Water pump; 13 - Spraying device; 14 - Axial flow fan or induced draft fan; 15 - Spraying device; 16 - Demisting device; 17 - Make-up water pipeline; 18 - Chemical dosing device; 19 - Sewage pipeline; 20 - Online ammonia concentration analyzer; 21 - Online flue gas component analyzer; 22 - Temperature sensor on the heat transfer surface of the evaporation unit; 23 - Temperature sensor on the heat transfer surface of the condensation unit; 24 - Temperature sensor in the water tank; 25 - Water level sensor; 26 - Water quality monitoring probe; 27 - PLC controller; 28 - Sealed pipeline. Detailed Embodiments

[0027] To make the objectives, technical solutions, and advantages of the present application clearer, the present invention will be further described below with reference to the drawings and embodiments. The embodiments of the present invention include, but are not limited to, the following embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the scope of protection of the present application.

[0028] Please refer to Figures 1-4, the present invention provides a technical solution: an ammonia escape deep recovery device, comprising: a) a mutually independent flue gas circulation sealed cavity 1 and a cooling cavity 2. The top of the flue gas circulation sealed cavity 1 is provided with a flue gas inlet 3, the lower side wall is provided with a flue gas outlet 4, and the bottom is provided with a condensate discharge outlet 5. The lower side wall of the cooling cavity 2 is provided with an air inlet 6, and the top is provided with an air outlet 7; b) a heat transfer assembly, mainly composed of an evaporation unit 8 and a condensation unit 9 to form a closed vacuum structure. The vacuum degree inside the heat transfer assembly is 10 -4 -10 -1 Pa. The evaporation unit 8 is internally provided with a heat medium and is arranged inside the flue gas circulation sealed cavity 1, and the condensation unit 9 is arranged inside the cooling cavity 2; c) a water circulation system, including a water tank 10 arranged at the bottom or below the cooling cavity 2, a water pump 12 connected to the water tank 10 in sequence through a pipeline 11, and a spray device 13 at the top of the condensation unit 9; d) an axial flow fan or an induced draft fan 14 arranged at the air outlet 7.

[0029] Further, the installation elevation of the evaporation unit 8 is lower than that of the condensation unit 9.

[0030] Further, the outer surface of the evaporation unit 8 is provided with an anti-corrosion coating.

[0031] Further, the filling amount of the heat medium in the heat transfer assembly is 5%-100% of the volume of the evaporation unit.

[0032] Further, the upper part of the flue gas circulation sealed cavity 1 is also provided with a spray device 15.

[0033] Further, the flue gas outlet 4 is provided with a demisting device 16, and the demisting device 16 can be a wire mesh demisting device, a baffle demisting device, a cyclone demisting device, a porous material demisting device, etc.

[0034] Further, the water tank 10 is provided with a make-up water pipeline 17, a dosing device 18, and a sewage pipeline 19.

[0035] Further, the make-up water pipeline 17, the dosing device 18, the sewage pipeline 19, and the spray device 15 are all provided with automatic control devices.

[0036] Further, the axial flow fan or the induced draft fan 14 and the water pump 12 are provided with frequency conversion control devices.

[0037] Furthermore, it further includes an intelligent control system, which comprises: an on-line ammonia concentration analyzer 20 and an on-line flue gas composition analyzer 21 disposed in the flue gas flow sealing cavity 1, a temperature sensor 22 disposed on the heat exchange surface of the evaporation unit and a temperature sensor 23 disposed on the heat exchange surface of the condensation unit; a temperature sensor 24, a water level sensor 25, a water quality monitoring probe 26 and a PLC controller 27 disposed in the water tank; the PLC controller 27 serves as the core control module, and dynamically adjusts the fan speed, the spray water volume and the spray pressure based on the temperature difference of the condensation unit, the real-time ammonia concentration and the flue gas composition data, and in combination with the dew point temperature obtained by converting the flue gas composition; the PLC controller controls the start and stop of the spray device according to the real-time feedback of the ammonia concentration and the water content in the flue gas; the PLC controller also controls the valves to perform water replenishment, chemical addition and sewage discharge operations by analyzing the temperature, water level and water quality monitoring results in the water tank.

[0038] Embodiment 1: An escape ammonia deep recovery device, as Figures 1-3 shown, includes: a flue gas flow sealing cavity 1 and a cooling cavity 2 which are independent of each other and arranged side by side.

[0039] The flue gas flow sealing cavity 1 is a place for providing flue gas cooling. A flue gas inlet 3 is provided at the top of the flue gas flow sealing cavity 1, a flue gas outlet 4 is provided at the lower side wall, and a condensate discharge outlet 5 is provided at the bottom. A spray device 15 is further provided at the upper part of the flue gas flow sealing cavity 1. The spray device 15 is connected to a water pipe. When the water content in the flue gas is low and the escape ammonia concentration is high, water mist is sprayed into the flue gas to ensure the recovery efficiency of the escape ammonia. A demisting device 16 is provided at the flue gas outlet 4. The demisting device 16 can be a wire mesh demisting device, a baffle demisting device, a cyclone demisting device or a porous material demisting device, etc. In this embodiment, a wire mesh demisting device is selected.

[0040] The cooling cavity 2 is a place for providing the flow of a cooling medium. An air inlet 6 is opened at the bottom side wall of the cooling cavity, and an air outlet 7 is provided at the top. An axial flow fan 14 is provided at the air outlet to force the air to convect through the cooling cavity. According to the requirements of the flue gas treatment volume and the heat exchange amount, multiple groups of independent cooling cavities 2 can be provided. The design, manufacture and installation of the cooling cavity adopt modular operation, which can greatly reduce the on-site installation period. In this embodiment, 4 groups of independent cooling cavities are provided.

[0041] The heat of the flue gas exchanges heat with the cooling medium through the heat transfer component. The heat transfer component consists of an evaporation unit 8 and a condensation unit 9 to form a closed vacuum structure. The evaporation unit 8 is internally provided with a heat transfer medium and is arranged inside the sealed cavity 1 for flue gas flow. The condensation unit 9 is arranged inside the cooling cavity 2. The installation elevation of the evaporation unit 8 is lower than that of the condensation unit 9, and the gravity difference can be utilized to drive the circulation of the heat transfer medium. To further improve the heat exchange efficiency of the heat exchange component, the heat transfer component is evacuated, and the vacuum degree is 10 -4 Pa. Further, an anti-corrosion coating is provided on the outer wall of the heat exchange surface of the evaporation unit 8 to improve the service life of the evaporation unit and reduce the maintenance cost of the heating surface. The heat transfer medium in the heat exchange component can be a low-boiling medium such as water, ethanol, acetone, or Freon. According to the magnitude of the heat exchange amount, through thermal calculation, the filling amount of the heat transfer medium is determined. In this embodiment, the filling amount of the heat transfer medium in the heat transfer component is 5% of the volume of the evaporation unit.

[0042] The water circulation system includes a water tank 10 arranged below the cooling cavity 2, a water pump 12 connected to the water tank 10 in sequence through a pipeline 11, and a spraying device 13 located above the condensation unit 9. The spraying device 13 forms a uniform water film on the surface of the condensation unit 9 to enhance heat exchange. A make-up water pipeline 17, a dosing device 18, and a sewage pipeline 19 are provided in the water tank. According to the water level, temperature, and water quality analysis results of the water tank, make-up water, dosing, and sewage discharge operations are carried out.

[0043] The device is also provided with an intelligent control system, including: an ammonia concentration on-line analysis device 20 and a flue gas component on-line analysis device 21 arranged in the sealed cavity for flue gas flow, a temperature sensor 22 arranged on the heat exchange surface of the evaporation unit and a temperature sensor 23 arranged on the heat exchange surface of the condensation unit; a temperature sensor 24, a water level sensor 25, a water quality monitoring probe 26, and a PLC controller 27 arranged in the water tank; the PLC controller 27 serves as the core control module. Based on the temperature difference of the condensation unit, the real-time ammonia concentration, and the flue gas component data, combined with the dew point temperature calculated from the flue gas component conversion, the fan speed, the spraying water volume, and the spraying pressure are dynamically adjusted; the PLC controller controls the start and stop of the spraying device according to the real-time feedback of the ammonia concentration and the water content in the flue gas; the PLC controller also controls the valves to carry out make-up water, dosing, and sewage discharge operations by analyzing the temperature, water level, and water quality monitoring results in the water tank.

[0044] The working process of the device is as follows: The flue gas enters the flue gas flow sealing cavity from the flue gas inlet at the top of the flue gas flow sealing cavity, and then flows through the evaporation unit, where it comes into full contact with the heat transfer surface of the evaporation unit for heat exchange. The heat released by the flue gas is transferred to the heat medium through the wall of the evaporation unit. After the heat medium absorbs heat and vaporizes, the steam enters the condensation unit through the vacuum channel. In the condensation unit, the steam releases latent heat and liquefies through a triple cooling mechanism: the spray water film absorbs most of the heat through sensible heat exchange, the air convection driven by the axial flow fan further enhances the heat exchange, and at the same time, the latent heat released by the phase change of the heat medium is transferred to the cooling medium through the wall of the condensation unit. The liquefied heat medium flows back to the evaporation unit by gravity difference, forming a closed cycle. The heat released by the flue gas drops below the dew point temperature, and the water vapor in the flue gas condenses into liquid. Due to the characteristic that ammonia is easily soluble in water, the escaped ammonia dissolves in the condensed water and is discharged through the condensation pipeline. The discharged condensed water can be sent to the water treatment system, and ammonia water is recovered and reused through processes such as filtration, evaporation, and condensation in the water treatment system. The reclaimed water obtained after removing substances such as ammonia in the water treatment system can be used for applications such as circulating cooling water. The cooling water absorbs heat and then flows into the water tank for recycling, and the makeup water pipeline, dosing device, and sewage pipeline maintain the water quality stability.

[0045] The intelligent control system integrates multiple types of sensors, and can dynamically track the dew point temperature (accuracy of ±0.5°C), on-line monitor the ammonia concentration (resolution of 0.1 mg / m³), have an adaptive spray adjustment system (flow control accuracy of ±2%), and analyze the flue gas composition, etc. The PLC controller adjusts the fan speed, the spray amount of the cooling liquid, and the spray amount of the water mist in real time to ensure that the condensation phase change process is accurately controllable, and the volatility of the ammonia removal efficiency is <5%.

[0046] The variable frequency control of the axial flow fan and the water pump matches the real-time heat load change to avoid energy waste.

[0047] The advantages of this device stem from the physical condensation phase change technology based on the characteristic that ammonia is easily soluble in water. The high-temperature flue gas (100 - 120°C) is quickly cooled below the dew point (45 - 95°C), enabling the escaped ammonia to fully dissolve in the condensed water. The removal efficiency is not affected by the complex conditions and fluctuations of the flue gas, and the ammonia escape concentration can be stably reduced from 800 - 15 mg / m³ to below 10 mg / m³.

[0048] The synergistic effect of multiple heat transfer mechanisms is adopted: the spray water cooling directly absorbs heat through sensible heat exchange, the air convection breaks the thermal boundary layer to improve the heat exchange efficiency, and the phase change of the heat medium utilizes latent heat to greatly increase the unit heat transfer amount. The heat transfer component is evacuated to reduce the heat conduction loss of gas molecules, and at the same time, the boiling point of the heat medium is reduced to accelerate the phase change process. The intelligent control system not only maintains the stable operation of the system, but also minimizes energy consumption and ensures high and stable ammonia removal.

[0049] Through theoretical calculation, this device can cool 300,000 Nm³ / h of flue gas from 120°C to 52°C, reduce the ammonia slip concentration from 800 mg / m³ to 10 mg / m³, and achieve a synergistic removal rate of NOx and SOx of 20%.

[0050] Example 2: A deep recovery device for escaped ammonia, as Figure 4 shown, comprising: a flue gas flow sealing cavity 1 and a cooling cavity 2 arranged independently of each other. Among them, the cooling cavity 2 is arranged above the flue gas flow sealing cavity 1. This arrangement greatly reduces the floor area of the equipment and is particularly suitable for renovation projects with limited space.

[0051] The flue gas flow sealing cavity 1 is a place for providing flue gas cooling. A flue gas inlet 3 is provided at the top of the flue gas flow sealing cavity 1, a flue gas outlet 4 is provided on the lower side wall, and a condensate discharge outlet 5 is provided at the bottom. A spray device 15 is also provided in the upper part of the flue gas flow sealing cavity 1. The spray device 15 is connected to a water pipe. When the moisture content in the flue gas is low and the ammonia slip concentration is high, water mist is sprayed into the flue gas to ensure the recovery efficiency of the escaped ammonia. A demisting device 16 is provided at the flue gas outlet 4. The demisting device 16 can be a wire mesh demisting device, a baffle demisting device, a cyclone plate demisting device, a porous material demisting device, etc. In this embodiment, a wire mesh demisting device is selected.

[0052] The cooling cavity 2 is a place for providing the flow of the cooling medium. An air inlet 6 is opened on the side wall at the bottom of the cooling cavity, and an air outlet 7 is provided at the top. A blower 14 is provided at the air outlet to force the air to convect through the cooling cavity. According to the requirements of the flue gas treatment volume and the heat transfer amount, multiple groups of independent cooling cavities 2 can be set. The design, manufacture, and installation of the cooling cavity adopt modular operation, which can greatly reduce the on-site installation period. In this embodiment, 2 groups of independent cooling cavities are set.

[0053] The heat of the flue gas exchanges heat with the cooling medium through the heat transfer component. The heat transfer component is composed of an evaporation unit 8 and a condensation unit 9 connected by a sealed pipeline 28 to form a closed vacuum structure. The evaporation unit 8 is internally provided with a heat transfer medium and is arranged inside the flue gas flow sealing cavity 1, and the condensation unit 9 is arranged inside the cooling cavity 2. The installation elevation of the evaporation unit 8 is lower than that of the condensation unit 9, and the gravity difference can be used to drive the circulation of the heat transfer medium. To further improve the heat transfer efficiency of the heat exchange component, the heat transfer component is evacuated, and the vacuum degree is 10 -1Pa. Further, an anti-corrosion coating is provided on the outer wall of the heat exchange surface of the evaporation unit 8 to improve the service life of the evaporation unit and reduce the maintenance cost of the heating surface. The heat transfer medium in the heat exchange component can be water, ethanol, acetone, Freon or other media. According to the magnitude of the heat transfer amount, through thermal calculation, the filling amount of the heat transfer medium is determined. In this embodiment, the filling amount of the heat transfer medium in the heat transfer component is 100% of the volume of the evaporation unit.

[0054] The water circulation system includes a water tank 10 arranged below the cooling cavity 2, a water pump 12 connected to the water tank in sequence through a pipeline 11, and a spraying device 13 located above the condensation unit 9. The spraying device 13 forms a uniform water film on the surface of the condensation unit 9 to enhance heat exchange. A make-up water pipeline 17, a chemical dosing device 18 and a sewage pipeline 19 are provided in the water tank. According to the water level, temperature and water quality analysis results of the water tank, make-up water, chemical dosing and sewage discharge operations are carried out.

[0055] The device is also provided with an intelligent control system, including: an ammonia concentration on-line analysis device 20 and a flue gas component on-line analysis device 21 arranged in the flue gas circulation sealed cavity, a temperature sensor 22 arranged on the heat exchange surface of the evaporation unit and a temperature sensor 23 arranged on the heat exchange surface of the condensation unit; a temperature sensor 24, a water level sensor 25, a water quality monitoring probe 26 and a PLC controller 27 arranged in the water tank; the PLC controller 27 is used as the core control module, and based on the temperature difference of the condensation unit, the real-time ammonia concentration and flue gas component data, combined with the dew point temperature obtained by converting the flue gas components, dynamically adjusts the fan speed, the spraying water volume and the spraying pressure; the PLC controller controls the start and stop of the spraying device according to the real-time feedback of the ammonia concentration and the moisture content in the flue gas; the PLC controller also controls the valves to carry out make-up water, chemical dosing and sewage discharge operations by analyzing the temperature, water level and water quality monitoring results in the water tank.

Claims

1. An ammonia escape deep recovery device, characterized in that, Comprising: a) A flue gas flow sealing cavity and a cooling cavity that are independent of each other. The top of the flue gas flow sealing cavity is provided with a flue gas inlet, the lower side wall is provided with a flue gas outlet, and the bottom is provided with a condensate discharge outlet. The lower side wall of the cooling cavity is provided with an air inlet, and the top is provided with an air outlet; b) The heat transfer component mainly consists of an evaporation unit and a condensation unit to form a closed vacuum structure. The vacuum degree inside the heat transfer component is 10 -4 -10 -1 Pa. The evaporation unit is internally provided with a heat transfer medium and is arranged inside a sealed cavity for flue gas flow. The condensation unit is arranged inside a cooling cavity; c) A water circulation system, including a water tank arranged at the bottom or below the cooling cavity, a water pump connected to the water tank in sequence through a pipeline, and a spraying device at the top of the condensation unit; d) An axial flow fan or an induced draft fan arranged at the air outlet.

2. The ammonia escape deep recovery device according to claim 1, characterized in that The installation elevation of the evaporation unit is lower than that of the condensation unit.

3. The ammonia escape depth recovery device according to claim 1, characterized in that, The outer surface of the evaporation unit is provided with an anti-corrosion coating.

4. The ammonia escape deep recovery device according to claim 1, characterized in that The filling amount of the heat transfer medium in the heat transfer component is 5%-100% of the volume of the evaporation unit.

5. The ammonia escape deep recovery device according to claim 1, characterized in that, The upper part of the flue gas flow sealing cavity is also provided with a spraying device.

6. The ammonia escape deep recovery device according to claim 1, characterized in that The flue gas outlet is provided with a demisting device.

7. The ammonia escape deep recovery device according to claim 1, characterized in that, The water tank is provided with a make-up water pipeline, a chemical dosing device and a sewage pipeline.

8. The ammonia escape depth recovery device according to claim 7, characterized in that, The make-up water pipeline, the chemical dosing device, the sewage pipeline and the spraying device are all provided with automatic control devices.

9. The ammonia escape depth recovery device according to any one of claims 1-8, characterized in that, The axial flow fan or the induced draft fan and the water pump are provided with variable frequency control devices.

10. The ammonia escape depth recovery device according to claim 9, wherein, It also includes an intelligent control system. The intelligent control system includes: an ammonia concentration on-line analysis device and a flue gas composition on-line analysis device arranged in the flue gas flow sealing cavity, temperature sensors arranged on the heat transfer surfaces of the evaporation unit and the condensation unit, temperature sensors, water level sensors, water quality monitoring probes and a PLC controller arranged in the water tank; The PLC controller is used as the core control module. Based on the temperature difference of the condensation unit, the real-time ammonia concentration and the flue gas composition data, combined with the dew point temperature calculated from the flue gas composition conversion, it dynamically adjusts the fan speed, the spraying water volume and the spraying pressure; The PLC controller controls the start and stop of the spraying device according to the real-time feedback of the ammonia concentration and the water vapor content in the flue gas; The PLC controller also controls the valves to perform water replenishment, chemical dosing and sewage discharge operations by analyzing the temperature, water level and water quality monitoring results in the water tank.

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