A sulfur tail gas resourceful treatment system

Abstract

This invention discloses a sulfur tail gas resource recovery system, relating to the field of sulfur tail gas treatment technology. It includes an acidic water stripping unit, a sulfur tail gas treatment unit, and an ammonium sulfate preparation unit, as well as an ammonia water delivery unit, a negative pressure regulation unit, a detection unit, and a central control unit. Through the design of the central control unit, detection unit, extraction assembly, and variable diameter component, this invention effectively solves the problem of dynamic ammonia concentration distribution shift caused by upstream operating condition fluctuations in the acidic water stripping unit. This ensures that the extraction assembly is always aligned with the ammonia-rich area, guaranteeing the stability of ammonia water quality and the consistency of downstream desulfurization effects. Simultaneously, the passive flow-guiding characteristic of the variable diameter component structure allows the system to automatically expand its extraction range under high load conditions. Without relying on active moving parts for radial expansion, it achieves on-demand capture of high-concentration ammonia at the center of the tower, significantly improving ammonia resource recovery efficiency and energy utilization efficiency.

Description

Technical Field

[0001] This invention relates to the field of sulfur tail gas treatment equipment, and in particular to a sulfur tail gas resource utilization treatment system. Background Technology

[0002] In the actual production process of refining and chemical enterprises, acidic water stripping units and sulfur recovery units are usually operated as two independent units. The former generates a large amount of ammonia-rich gas flow when treating sulfur-containing wastewater, while the latter requires a large amount of ammonia or alkaline solution as absorbent when treating tail gas. Traditional treatment methods often treat ammonia as waste gas and incinerate or perform complex distillation purification, which is not only energy-intensive but also wastes the potential resource value. At the same time, the cost of treating sulfur dioxide in sulfur tail gas remains high.

[0003] Some existing technologies integrate acidic water stripping devices with sulfur tail gas treatment systems. The main process involves extracting the ammonia-rich gas phase inside the acidic water stripping tower and condensing it to produce ammonia water, which is then transported through pipelines to the sulfur tail gas treatment unit as a desulfurization absorbent, ultimately converting sulfur dioxide into ammonium sulfate fertilizer.

[0004] However, the operating conditions of the acidic water stripping unit are affected by factors such as changes in the properties of upstream crude oil, adjustments in processing load, and fluctuations in stripping steam volume. The temperature gradient and ammonia concentration distribution inside the tower will dynamically shift, making it difficult for the fixed ammonia extraction port to always be aligned with the ammonia-rich area. It is easy to deviate from the optimal extraction position and even extract impurities such as hydrogen sulfide that have not yet been stripped, resulting in huge fluctuations in the quality of ammonia water. Downstream tail gas treatment units will experience problems such as decreased sulfur dioxide absorption efficiency, deterioration of ammonium sulfate product quality, and catalyst poisoning and deactivation.

[0005] Furthermore, under non-steady-state conditions such as start-up and shutdown of the unit, the fixed ammonia extraction port will almost inevitably extract substandard materials. These materials require additional storage and processing facilities; otherwise, they will cause secondary pollution and waste of resources.

[0006] To address these issues, this invention proposes a sulfur tail gas resource recovery system. Summary of the Invention

[0007] The purpose of this invention is to provide a sulfur tail gas resource recovery system to solve the technical problems mentioned in the background art.

[0008] To achieve the above objectives, the present invention provides the following technical solution: a sulfur tail gas resource utilization treatment system, comprising an acidic water stripping device, a sulfur tail gas treatment unit, and an ammonium sulfate preparation unit, and further comprising: An ammonia water conveying unit is connected between the acidic water stripping device and the sulfur tail gas treatment unit. It is used to convert the ammonia-rich gas produced by the acidic water stripping device into ammonia water and convey it to the sulfur tail gas treatment unit. The ammonia water conveying unit includes an air extraction component that is installed inside the acidic water stripping device and whose position is adjustable. The ammonia water delivery unit also includes at least two side-line ammonia extraction pipes, which are located at different heights of the acid water stripping device. A negative pressure regulating unit, which is connected to the ammonia water delivery unit, is used to regulate the negative pressure of ammonia extraction. The detection unit includes a sulfur dioxide concentration monitor installed at the outlet of the sulfur tail gas treatment unit. The central control unit is electrically connected to the ammonia delivery unit, the negative pressure regulation unit, and the detection unit. The central control unit is used to receive feedback signals from the detection unit and adjust the position of the air extraction component or the negative pressure value of the negative pressure regulation unit according to a preset control strategy.

[0009] Preferably, the number of the air extraction components is consistent with the number of the side-line ammonia extraction pipes and they correspond one-to-one.

[0010] Preferably, the gas extraction assembly includes a gas collection hood with an arc-shaped plate structure, and its arc is consistent with the arc of the inner wall of the acidic water stripping device. The gas collection hood is slidably connected to the acidic water stripping device. A cavity is opened inside the gas collection hood. A plurality of gas extraction holes facing the center of the acidic water stripping device are opened on one side of the cavity. A connecting pipe communicating with the cavity is provided between the gas collection hood and the side-line ammonia extraction pipe. A telescopic pipe is provided at the connection end of the connecting pipe and the side-line ammonia extraction pipe. A drive mechanism is fixedly installed on one side of the gas extraction assembly. The drive mechanism is fixedly connected to the side-line ammonia extraction pipe and the connecting pipe, and is used to drive the connecting pipe and the gas collection hood to move up and down along the axial direction of the acidic water stripping device.

[0011] Preferably, the connecting pipe is provided with a reducing component inside. The reducing component includes an annular plate fixedly connected to the inner wall of the connecting pipe. The annular plate includes a contraction section near the gas collecting hood and an expansion section near the telescopic pipe. A throat is formed between the expansion section and the contraction section. A through hole communicating with the inside of the acidic water stripping device is opened on the side wall of the throat.

[0012] Preferably, an adjustment mechanism is provided within the through hole, comprising: A sliding ring is slidably connected to the circumferential side of the connecting pipe, and the sliding ring has multiple filter holes that match the through holes; A fixed tube is sleeved on one side of a sliding ring and fixedly connected to a connecting tube. One end of the sliding ring extends into the fixed tube and is slidably connected to the fixed tube in a sealed manner. A first elastic element is provided between the sliding ring and the fixed tube. A through groove is provided on the outer wall of the connecting tube, penetrating the throat. The sliding ring divides the interior of the fixed tube into a sealing cavity, and the sealing cavity communicates with the throat through the through groove. An annular baffle is disposed on the other side of the sliding ring and fixedly connected to the connecting pipe. One side of the annular baffle is provided with an opening through which the sliding ring can pass.

[0013] Preferably, the negative pressure regulating unit includes: A negative pressure tank, which is connected to each of the aforementioned side-line ammonia extraction pipelines; An air extraction device, which is connected to the negative pressure tank; The number of regulating valves is the same as that of the side-line ammonia extraction pipelines, and they are installed on the corresponding side-line ammonia extraction pipelines. The regulating valves are electrically connected to the central control unit.

[0014] Preferably, the ammonia water conveying unit further includes an ammonia water buffer tank for temporarily storing ammonia water formed by the condensation of ammonia gas; Multiple temperature sensors are installed axially within the rectification section of the acidic water stripping device. The detection unit also includes an online ammonia escape monitor installed at the outlet of the sulfur tail gas treatment unit, an ammonia concentration monitor installed on the ammonia water delivery pipeline, and a liquid level detection unit installed inside the ammonia water buffer tank. The central control unit is equipped with a sequence determination module, which sequentially determines the ammonia escape feedback signal, the temperature sensor feedback signal, the liquid level change rate feedback signal, and the sulfur dioxide concentration feedback signal, and executes the corresponding control command according to the determination result. In the process of sequential determination, when any feedback signal triggers its corresponding control command, the sequence determination module stops determining the subsequent feedback signals.

[0015] Preferably, the control instructions executed by the sequence determination module based on different feedback signals include: When the ammonia escape value exceeds the preset threshold, the central control unit sends a control command to the negative pressure regulating unit to reduce the negative pressure value. When the ammonia concentration is lower than the preset concentration threshold, the central control unit calculates the axial temperature gradient inside the tower based on the real-time feedback from the multiple temperature sensors, and estimates the axial position of the ammonia enrichment zone based on the preset temperature-concentration correlation model. It then sends a control command to the extraction component to move to the estimated position, and uses the feedback value from the ammonia concentration monitor for long-term calibration of the temperature-concentration correlation model. When the rate of change of liquid level exceeds the preset liquid level threshold, the central control unit sends a control command to the negative pressure adjustment unit to adjust the negative pressure value so as to match the ammonia water production with the downstream consumption. When the sulfur dioxide concentration exceeds the preset threshold range, the central control unit sends a control command to the negative pressure regulating unit to adjust the negative pressure value or sends a control command to the air extraction component to adjust the position based on the temperature gradient. The preset threshold range includes at least three preset thresholds. The central control unit is configured in master-slave control mode. Under normal operating conditions, only one main air extraction component is adjusted in position, while the other air extraction components remain locked or in the off state.

[0016] Preferably, the preset threshold range of sulfur dioxide concentration includes a first preset threshold, a second preset threshold, and a third preset threshold; When the sulfur dioxide concentration exceeds the first preset threshold but does not exceed the second preset threshold, the central control unit sends a first control command to the negative pressure adjustment unit to adjust the negative pressure value to the first target range. When the sulfur dioxide concentration exceeds the second preset threshold but does not exceed the third preset threshold, the central control unit sends a second control command to the negative pressure regulating unit to raise the negative pressure value to the second target range, so that the ammonia extraction range is switched from extraction in the tower wall area to extraction in the tower wall area and tower center area in a coordinated manner. When the feedback signal exceeds the third preset threshold, or when the sulfur dioxide concentration feedback signal still does not drop below the second preset threshold within the first time threshold after the execution of the second control command, a command for position adjustment based on temperature gradient is issued to the extraction component to find an extraction area with higher ammonia concentration.

[0017] Preferably, the inlet end of the ammonia water conveying unit is connected to the ammonia-rich gas outlet of the acidic water stripping device, and the outlet end is connected to the ammonia water inlet of the sulfur tail gas treatment unit, so as to convert the ammonia-rich gas produced by the acidic water stripping device into ammonia water and supply it to the sulfur tail gas treatment unit as a desulfurization absorbent. The ammonium sulfate preparation unit includes an oxidation reactor and a post-treatment unit. The slurry outlet of the sulfur tail gas treatment unit is connected to the inlet of the oxidation reactor of the ammonium sulfate preparation unit. This connection is used to oxidize the ammonium sulfite solution generated during desulfurization into an ammonium sulfate solution. The ammonium sulfate solution is then converted into solid ammonium sulfate by the post-treatment unit at the end of the oxidation reactor.

[0018] The beneficial effects of this invention are: This invention divides the treatment of sulfur tail gas into three stages. In the first stage, not only is process ammonia water that meets the requirements for tail gas treatment obtained, but the energy consumption of the distillation section of the acidic water stripping unit is also significantly reduced, avoiding the problem of excessive acidic gas entrainment in the ammonia. In the second stage of sulfur tail gas purification, the ammonia water produced in the first stage is used as an absorbent, turning the desulfurizing agent that originally needed to be purchased externally into a system-produced one. This eliminates the logistics costs and storage risks of purchasing liquid ammonia externally, and also achieves efficient removal of sulfur dioxide. Finally, in the third stage of product production, the ammonium sulfite generated from desulfurization is further oxidized and processed into solid ammonium sulfate fertilizer, upgrading the final product from a simple purification emission to a resource-based product, creating significant economic benefits.

[0019] Furthermore, by installing multiple temperature sensors along the axial direction in the rectification section, the location of the ammonia enrichment zone is predicted in real time using temperature gradients, overcoming the lag in traditional ammonia concentration detection and enabling rapid and accurate adjustment of the pumping component position. Simultaneously, a master-slave control mode is adopted, with only a single main pumping component adjusted during normal operation, avoiding flow field interference caused by simultaneous operation of multiple adjustable components and ensuring the reliability of pumping component position adjustment. In addition, the passive flow-guiding characteristics of the variable-diameter component structure allow the system to automatically expand the extraction range under high-load conditions, achieving on-demand capture of high-concentration ammonia at the tower center without relying on active moving parts for radial expansion, significantly improving ammonia resource recovery efficiency and energy utilization efficiency. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the overall structure of a sulfur tail gas resource utilization system according to the present invention.

[0021] Figure 2 This is a cross-sectional schematic diagram of the acidic water stripping tower of the present invention.

[0022] Figure 3 for Figure 2 A magnified schematic diagram of the structure at point A in the middle.

[0023] Figure 4 for Figure 3 Enlarged schematic diagram of the structure at point B.

[0024] Figure 5 This is a schematic diagram showing the disassembled adjustment mechanism of the present invention.

[0025] Figure 6 This is a schematic diagram of the control commands for the central control unit of the present invention.

[0026] Figure 7 This is a schematic diagram illustrating the graded control of sulfur dioxide at different threshold ranges according to the present invention.

[0027] The attached figures are labeled as follows: 1. Acidic water stripping unit; 2. Sulfur tail gas treatment unit; 3. Ammonium sulfate preparation unit; 4. Ammonia water delivery unit; 41. Vacuum extraction assembly; 411. Vacuum collection hood; 412. Cavity; 413. Vacuum extraction port; 414. Connecting pipe; 415. Telescopic pipe; 42. Side-line ammonia extraction pipeline; 43. Drive mechanism; 44. Variable diameter component; 441. Annular plate; 442. Contraction section; 443. Expansion section; 444. Throat; 445. Through hole; 45. Ammonia water buffer tank; 5. Negative pressure regulating unit; 51. Negative pressure tank; 52. Regulating valve; 6. Adjusting mechanism; 61. Sliding ring; 62. Filter hole; 63. Fixed tube; 64. First elastic element; 65. Sealing cavity; 66. Through groove; 67. Annular baffle; 7. Auxiliary mechanism; 71. Deflector plate; 72. Connecting rod. Detailed Implementation

[0028] 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. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Example 1

[0029] In the treatment of sulfur tail gas, a large amount of ammonia or alkaline solution is required as an absorbent. Acidic water stripping devices generate a large amount of ammonia-rich gas flow when treating sulfur-containing wastewater. However, most existing technologies do not combine the two, resulting in resource waste. Only a small number of existing technologies extract the ammonia-rich gas phase inside the acidic water stripping tower and condense it to produce ammonia water, which is then transported through pipelines to the sulfur tail gas treatment unit as a desulfurization absorbent, ultimately converting sulfur dioxide into ammonium sulfate fertilizer.

[0030] However, the operating conditions of the acidic water stripping unit are affected by factors such as changes in the properties of upstream crude oil, adjustments in processing load, and fluctuations in stripping steam volume. The temperature gradient and ammonia concentration distribution inside the tower will dynamically shift, making it difficult for the fixed ammonia extraction port to always be aligned with the ammonia-rich area. It is easy to deviate from the optimal extraction position and even extract impurities such as hydrogen sulfide that have not yet been stripped, resulting in huge fluctuations in the quality of ammonia water. Downstream tail gas treatment units will experience problems such as decreased sulfur dioxide absorption efficiency, deterioration of ammonium sulfate product quality, and catalyst poisoning and deactivation.

[0031] This embodiment was invented to solve the above problems.

[0032] Please see Figures 1 to 7As shown, an embodiment of the present invention provides a sulfur tail gas resource utilization system, including an acidic water stripping device 1, a sulfur tail gas treatment unit 2, and an ammonium sulfate preparation unit 3. It also includes an ammonia water conveying unit 4, a negative pressure regulating unit 5, a detection unit, and a central control unit. Further explanation of the sulfur tail gas treatment process is needed. This embodiment divides the treatment process into three stages. The first stage primarily uses an acidic water stripping tower, which has a rectification section and a stripping section. During the treatment of acidic water, a large amount of ammonia-rich gas is generated. The outlet of the side-stream ammonia extraction pipeline 42 is located in the upper-middle area of ​​the rectification section. After mass transfer in the condenser, the gas is condensed into ammonia water and stored in an ammonia water storage tank. Then, the ammonia water enters the second stage through a pipeline. The second stage primarily uses the sulfur tail gas treatment unit 2, whose core equipment is a desulfurization tower. A sulfur tail gas inlet is located at the bottom of the desulfurization tower, and an ammonia water spray layer or distribution layer is located above it. The ammonia water delivery unit 4 is connected to the ammonia water spray layer through a pipeline, allowing the ammonia water to come into countercurrent contact with the rising sulfur dioxide tail gas. As the ammonia water falls, it reacts with the sulfur dioxide in the tail gas to generate ammonium sulfite. The solution containing ammonium sulfite is located at the bottom of the desulfurization tower. Subsequently, the ammonium sulfite at the bottom of the desulfurization tower is extracted and enters the third stage, which is mainly based on the ammonium sulfate preparation unit 3. The ammonium sulfate preparation unit 3 includes an oxidation reactor and a post-treatment unit. The oxidation reactor is connected to the slurry outlet of the sulfur tail gas treatment unit 2 and is used to oxidize the desulfurization product into an ammonium sulfate solution. The oxidation reactor is usually a blower aeration tank or tower, which mainly blows sufficient air into the solution and forces the ammonium sulfite to be oxidized into a stable ammonium sulfate solution under the action of a catalyst. The post-treatment unit is connected to the oxidation reactor and converts the ammonium sulfate solution into solid ammonium sulfate product through evaporation concentration, crystallization, centrifugation separation, and drying.

[0033] The aforementioned acidic water stripping unit 1, sulfur tail gas treatment unit 2, and ammonium sulfate preparation unit 3 are all existing technologies as individual devices, and their specific structures will not be described in detail. However, by dividing the treatment of sulfur tail gas into three stages, the first stage not only obtains process ammonia water that meets the requirements for tail gas treatment, but also significantly reduces the energy consumption of the distillation section of the acidic water stripping unit 1, avoiding the problem of excessive acidic gas entrainment in the ammonia. In the second stage of sulfur tail gas purification, the ammonia water produced in the first stage is used as an absorbent, turning the desulfurizing agent that originally needed to be purchased externally into a system-produced product. This eliminates the logistics costs and storage risks of purchasing liquid ammonia externally, and also achieves efficient removal of sulfur dioxide. Finally, in the third stage of product production, the ammonium sulfite generated from desulfurization is further oxidized and processed into solid ammonium sulfate fertilizer, upgrading the final product from simple purification and emission to a resource-based product, creating significant economic benefits.

[0034] Furthermore, the ammonia water conveying unit 4 is connected between the acidic water stripping unit 1 and the sulfur tail gas treatment unit 2. The ammonia water conveying unit 4 includes an air extraction component 41 that is installed inside the acidic water stripping unit 1 and whose position is adjustable. The air extraction component 41 moves up and down along the axis of the acidic water stripping tower to find the optimal balance point of the ammonia-rich gas.

[0035] The negative pressure regulating unit 5 is connected to the ammonia water delivery unit 4 to regulate the negative pressure of ammonia extraction. In this embodiment, the negative pressure regulating unit 5 includes a negative pressure tank 51 connected to each side ammonia extraction pipeline 42. One side of the negative pressure tank 51 is connected to an air extraction device, and each side ammonia extraction pipeline 42 is equipped with a regulating valve 52. The regulating valve 52 is electrically connected to the central control unit.

[0036] The detection unit includes a sulfur dioxide concentration monitor installed at the outlet of sulfur tail gas treatment unit 2.

[0037] The central control unit is communicatively connected to the ammonia delivery unit 4, the negative pressure adjustment unit 5, and the detection unit. The central control unit is used to receive feedback signals from the detection unit and adjust the position of the air extraction component 41 or the negative pressure value of the negative pressure adjustment unit 5 according to the preset control strategy.

[0038] The ammonia water conveying unit 4 also includes at least two side-line ammonia extraction pipes 42, which are located at different heights of the acid water stripping device 1. The number of extraction components 41 is the same as the number of side-line ammonia extraction pipes 42 and they correspond one-to-one. The ammonia water conveying unit 4 also includes an ammonia water buffer tank 45, which is used to temporarily store ammonia water formed by the condensation of ammonia gas.

[0039] The extraction assembly 41 includes an arc-shaped plate-like gas collection hood 411, the curvature of which is consistent with the inner wall curvature of the acidic water stripping device 1. The gas collection hood 411 is slidably connected to the acidic water stripping device 1. A cavity 412 is provided inside the gas collection hood 411. A plurality of extraction holes 413 facing the center of the acidic water stripping device 1 are provided on one side of the cavity 412. A connecting pipe 414 communicating with the cavity 412 is provided between the gas collection hood 411 and the side-line ammonia extraction pipe 42. A telescopic pipe 415 is provided at the connection end of the connecting pipe 414 and the side-line ammonia extraction pipe 42. In this embodiment, the telescopic pipe 415 is a metal sleeve made of corrosion-resistant material, which has a multi-stage telescopic effect. In other embodiments, a corrugated pipe or other pipe with telescopic function made of corrosion-resistant material can also be used, which is not limited here.

[0040] A drive mechanism 43 is fixedly installed on one side of the extraction assembly 41. The drive mechanism 43 is fixedly connected to the side-line ammonia extraction pipe 42 and the connecting pipe 414 respectively, and is used to drive the connecting pipe 414 and the gas collection hood 411 to move up and down along the axial direction of the acidic water stripping device 1.

[0041] In this embodiment, the drive mechanism 43 includes a support plate fixedly connected to the telescopic tube 415. A multi-stage hydraulic telescopic rod is fixedly connected to the support plate. The end of the multi-stage hydraulic telescopic rod away from the support plate is fixedly connected to the connecting tube 414. The bottom of the multi-stage hydraulic telescopic rod is connected to a liquid inlet pipe. One end of the liquid inlet pipe passes through the acidic water stripping device 1 and is connected to a liquid supply device. The multi-stage hydraulic telescopic rod drives the telescopic tube 415 to extend and retract through the power provided by the liquid supply device, thereby realizing the positional change of the connecting tube 414 and the gas collecting hood 411.

[0042] During use, when the optimal ammonia concentration position inside the acidic water stripping tower dynamically shifts, the drive mechanism 43 can move the extraction component 41 up and down inside the acidic water stripping tower to find the optimal ammonia extraction point. Specifically: When the liquid supply device in the drive mechanism 43 supplies liquid to the multi-stage hydraulic telescopic rod through the pipeline, the connecting pipe 414 and the gas collection hood 411 move upward under the hydraulic pressure. Conversely, when the liquid supply device extracts the liquid inside the multi-stage hydraulic telescopic rod, the connecting pipe 414 and the gas collection hood 411 move downward under the hydraulic pressure.

[0043] By cooperating with the extraction component 41 and the drive mechanism 43, the dynamic changes in the axial ammonia concentration distribution within the acidic water stripping unit 1 are actively tracked. This avoids the problem of the ammonia extraction port deviating from the optimal extraction position due to fluctuations in operating conditions, or even the extraction of impurities such as hydrogen sulfide that have not yet been stripped. This improves the quality stability of the ammonia water and ensures that the downstream sulfur tail gas treatment unit 2 maintains a high level of sulfur dioxide absorption efficiency. Furthermore, under non-steady-state operating conditions such as unit start-up and shutdown, the position of the extraction component 41 can be adjusted in advance based on production experience, enabling the tail gas treatment system to avoid low-quality ammonia areas in the early stages, reducing the generation of unqualified materials, lowering the risk of secondary pollution, and reducing additional storage and treatment costs. Example 2

[0044] In acidic water stripping towers, ammonia concentrations not only vary along the axial direction within the tower, but also exhibit significant non-uniformity in the radial direction due to the complex flow characteristics of the gas-liquid two-phase flow. This is particularly pronounced in stripping towers with larger inner diameters. Specifically, the ammonia concentration in the gas phase is often lower in the tower wall region due to the wall effect and the downward flow of the liquid phase. Meanwhile, the gas velocity is higher and mass transfer is more efficient in the central region of the tower, which usually accumulates a higher concentration of ammonia. However, directly installing a device like a gas collecting hood 411 in the middle can interfere with the main gas flow in the tower due to the large volume of the gas collecting hood 411, thereby affecting the gas-liquid mass transfer effect.

[0045] Therefore, further improvements were made based on the above embodiments.

[0046] Please see Figures 3 to 5As shown, the connecting pipe 414 is inclined, and a reducing member 44 is provided inside the connecting pipe 414. The reducing member 44 includes an annular plate 441 fixedly connected to the inner wall of the connecting pipe 414. The annular plate 441 includes a contraction section 442 near the gas collecting hood 411 and an expansion section 443 near the telescopic pipe 415. A throat 444 is formed between the expansion section 443 and the contraction section 442. A through hole 445 communicating with the inside of the acidic water stripping device 1 is provided on the side wall of the throat 444.

[0047] An adjustment mechanism 6 is provided inside the through hole 445. The adjustment mechanism 6 includes a sliding ring 61 slidably connected to the circumference of the connecting pipe 414. In this embodiment, a corrosion-resistant sealing ring is provided between the sliding ring 61 and the connecting pipe 414. The sliding ring 61 has a plurality of filter holes 62 that match the through hole 445. A fixed pipe 63 located on one side of the sliding ring 61 is fixedly connected to the connecting pipe 414. One end of the sliding ring 61 that extends into the fixed pipe 63 is slidably and sealingly connected to the fixed pipe 63. A first elastic element 64 is provided between the sliding ring 61 and the fixed pipe 63. A through throat 444 is provided on the outer wall of the connecting pipe 414. The through groove 66, the sliding ring 61 divides the inside of the fixed tube 63 to form a sealing cavity 65, the sealing cavity 65 is connected to the throat 444 through the through groove 66, and an annular baffle 67 located on the other side of the sliding ring 61 is fixedly connected to the connecting tube 414. The annular baffle 67 is symmetrically arranged with the fixed tube 63. One side of the annular baffle 67 is provided with an opening through which the sliding ring 61 can pass. The annular baffle 67 and one end of the sliding ring 61 are sealed and slidably connected. A movable cavity is formed between the sliding ring 61 and the annular baffle 67. When the sliding ring 61 is reset, the annular baffle 67 can scrape off the crystals or droplets accumulated at the filter hole 62.

[0048] To enable the sliding ring 61 to move more smoothly, an auxiliary mechanism 7 is provided inside the variable diameter component 44. Specifically, the auxiliary mechanism 7 includes multiple guide plates 71 located in the throat region 444 and equidistantly arranged. In this embodiment, the guide plates 71 have an arc-shaped structure. A connecting rod 72 is fixedly connected to one side of each of the multiple guide plates 71. One end of the connecting rod 72 extending out of the through groove 66 is fixedly connected to the inner wall of the sliding ring 61. The height of the multiple guide plates 71 gradually increases along the gas flow direction. When the negative pressure regulating unit 5 maintains the extraction negative pressure at a low range, the guide plates 71 cannot overcome the action of the first elastic element 64 to move. However, when the negative pressure regulating unit 5 gradually adjusts the extraction negative pressure to a higher range, the guide plates 71, under the push of the gas, have the ability to move towards the solid. The fixed pipe 63 tends to move in the direction of the fixed pipe 63, and after the negative pressure value reaches a certain level, in conjunction with the negative pressure environment of the sealing cavity 65, the sliding ring 61 overcomes the elastic force of the first elastic element 64 and slides towards the side closer to the fixed pipe 63. This setting not only makes the sliding ring 61 slide more smoothly, but also when the extracted gas washes over the multiple guide plates 71, the liquid in the gas deviates from the streamline due to inertia and hits the surface of the guide plate 71, and finally gathers on its surface to form a liquid film or droplets. Under the action of gravity or airflow shear force, it drips from the end of the guide plate 71, thereby realizing gas-liquid separation. In addition, since the connecting pipe 414 is in an inclined state, the liquid dripping on the throat 444 moves towards the side of the gas collection hood 411 under the action of gravity and will not enter the side ammonia extraction pipe 42.

[0049] During use, under normal conditions, when the negative pressure regulating unit 5 maintains the extraction negative pressure at a low range, the airflow mainly enters the connecting pipe 414 from the tower wall area through the extraction hole 413 of the gas collecting hood 411, and finally passes through the connecting pipe 414 and the telescopic pipe 415 into the side ammonia extraction pipe 42. At this time, the negative pressure in the sealing cavity 65 and the gas thrust on the guide plate 71 are insufficient to make the sliding ring 61 overcome the elastic constraint of the first elastic element 64. The filter hole 62 on the sliding ring 61 is not connected to the through hole 445 of the throat 444. The through hole 445 is in a closed state and cannot form a Venturi effect.

[0050] When the downstream ammonium sulfate preparation unit 3 needs to increase its output or the sulfur dioxide concentration feedback signal is high, the central control unit sends a control command to the negative pressure adjustment unit 5 to increase the negative pressure value. At this time, the negative pressure value of the sealed cavity 65 inside the fixed tube 63 increases. Under the gas push and negative pressure attraction, the sliding ring 61 overcomes the action of the first elastic element 64 and slides inside the fixed tube 63. As the negative pressure gradually increases, the displacement of the sliding ring 61 continues to increase. The overlapping area of ​​the multiple filter holes 62 and the through holes 445 set on it also gradually increases from zero, showing a change process from completely closed, gradually partially open, until fully open.

[0051] When the negative pressure in the connecting pipe 414 increases only slightly, the through hole 445 and the filter hole 62 are partially connected, and their cross-sectional area is small. At this time, the flow rate of ammonia-rich gas drawn from the central area of ​​the stripping tower is limited to a certain extent. The system still mainly uses the gas collection hood 411 for extraction, and the gas in the center of the tower is only used as a supplement. As the negative pressure continues to rise, the cross-sectional area of ​​the through hole 445 gradually increases, and the flow rate of ammonia in the central area of ​​the tower also increases. Until the negative pressure approaches the maximum value, all filter holes 62 and through holes 445 are completely aligned, and the cross-sectional area of ​​through holes 445 reaches its maximum. At this time, the tower wall area and the central area of ​​the tower achieve true collaborative extraction.

[0052] It should be noted that the diameter of the filter hole 62 on the sliding ring 61 is much smaller than the diameter of the through hole 445. When the gas in the center of the tower passes through the filter hole 62, the pore size design of the filter hole 62 causes the tiny liquid droplets entrained in the gas to be intercepted due to surface tension when passing through, and flow back into the tower along the surface of the sliding ring 61 under the action of gravity. The clean gas phase smoothly enters the connecting pipe 414 and merges with the mainstream. In the partially open state, due to the small actual flow cross section, the gas velocity when passing through the filter hole 62 is high. This high-speed airflow has a more significant impact and interception effect on the droplets, further enhancing the gas-liquid separation efficiency. Only when the negative pressure is close to the maximum value and the filter hole 62 is fully open, the gas velocity is relatively reduced. However, at this time, due to the large gas phase load, the acceptable liquid removal effect can still be maintained by relying entirely on the interception effect of the filter hole 62.

[0053] When the negative pressure in the connecting pipe 414 returns to the normal level, the sliding ring 61 is reset under the action of the first elastic element 64. At this time, the annular baffle 67 will clean the filter hole 62 to prevent excessive liquid from accumulating and crystallizing.

[0054] It should be further added that, in other embodiments, the sliding mode of the sliding ring 61 can be changed from airflow-driven and negative pressure-driven to active drive. That is, an active control component is set between the acidic water stripping device 1 and the sliding ring 61. When the negative pressure value extracted by the negative pressure regulating device reaches a certain value, the active control component is activated. At this time, the sliding ring 61 can move towards the side closer to the fixed tube 63 under the action of the active control component. The reset of the sliding ring 61 can also be controlled by the active control component. Specifically, the active control component includes a winding device located outside the acidic water stripping device 1. A metal wire is fixedly connected to the side of the sliding ring 61 located inside the fixed tube 63. One end of the metal wire passes through the fixed tube 63 and is fixedly connected to the winding device. The metal wire is made of corrosion-resistant material. The winding device can control the sliding ring 61 to slide on the outer wall of the connecting tube 414 by winding and unwinding the drum.

[0055] In summary, this invention, through the synergistic effect of the variable diameter component 44 and negative pressure, achieves the expansion of the extraction range from the tower wall region to the tower center region as the negative pressure increases. This avoids the flow field disturbance caused by setting a fixed gas collecting hood 411 at the tower center, and also enables the acquisition of the radial ammonia-rich region under high load conditions. Furthermore, the gradual change in the cross-sectional area of ​​the through hole 445 achieves a smooth transition between tower wall extraction and central drainage. During the continuous adjustment of the negative pressure from low to high, the system does not suddenly switch the extraction source at a certain critical point. Instead, through the linear change of the cross-sectional area of ​​the through hole 445, the gas extraction volume at the tower wall gradually decreases while the central drainage volume gradually increases. This method not only avoids the violent fluctuations in the flow field caused by the large amount of gas extracted from the center of the stripping tower when a high negative pressure is suddenly established, but also prevents the gas phase stagnation in the tower wall region caused by the sudden drop in the extraction rate at the gas collecting hood 411, ensuring the stability of the gas-liquid phase balance inside the tower. Example 3

[0056] Please see Figure 6 and Figure 7 To facilitate understanding, this embodiment further supplements the control method of the central control unit, the specific content of which is as follows: Multiple temperature sensors are installed axially within the rectification section of the acidic water stripping device 1.

[0057] The detection unit also includes an online ammonia escape monitor installed at the outlet of the sulfur tail gas treatment unit 2, an ammonia concentration monitor installed on the ammonia water delivery pipeline, and a liquid level detection unit installed inside the ammonia water buffer tank 45.

[0058] The central control unit is equipped with a sequential judgment module. The sequential judgment module judges the ammonia escape feedback signal, temperature sensor feedback signal, liquid level change rate feedback signal, and sulfur dioxide concentration feedback signal in sequence, and executes the corresponding control commands based on the judgment results. During the sequential judgment process, when any feedback signal triggers its corresponding control command, the sequential judgment module stops judging the subsequent feedback signals. When the high-priority anomaly is eliminated and the relevant parameters return to the normal range, the central control unit automatically restarts the cyclic judgment from the first priority.

[0059] Specifically, the central control unit first obtains the feedback signal from the online ammonia escape monitoring instrument at the outlet of the sulfur tail gas treatment unit 2. When the ammonia escape value exceeds the preset threshold (which can be set according to national environmental emission standards), the central control unit immediately sends a control command to the negative pressure regulating unit 5 to reduce the negative pressure value and suspends the judgment of subsequent feedback signals.

[0060] When the ammonia concentration is lower than the preset concentration threshold (set according to the minimum ammonia concentration requirement of the downstream desulfurization reaction), the central control unit calculates the axial temperature gradient inside the tower based on the real-time feedback from the multiple temperature sensors, and estimates the axial position of the ammonia enrichment zone based on the preset temperature-concentration correlation model. It then sends a control command to the extraction assembly 41 to move to the estimated position, driving the gas collection hood 411 to move up and down along the axial direction of the acidic water stripping device 1. At the same time, the feedback value of the ammonia concentration monitor installed on the ammonia delivery pipeline is used for long-term calibration of the temperature-concentration correlation model.

[0061] Specifically, the central control unit first records the current values ​​of each temperature sensor. By comparing these values ​​with the built-in standard temperature-concentration characteristic curve, it determines the direction and magnitude of the positional deviation of the current ammonia enrichment zone relative to the gas collection hood 411. Then, it sends a command to the drive mechanism 43 to control the gas collection hood 411 to move to the estimated optimal extraction position in preset steps. After the movement is completed, the system continues to run for a period of time (e.g., 30-60 minutes). Once the ammonia concentration at the outlet of the ammonia buffer tank 45 stabilizes, the measured concentration value is compared with the concentration value predicted based on the temperature model. If the deviation exceeds the allowable range, the parameters of the temperature-concentration correlation model are automatically corrected to make subsequent predictions more accurate. The time constant of this long-cycle calibration loop is much greater than the response speed of the temperature gradient, avoiding control oscillations caused by the lag in ammonia concentration analysis.

[0062] The following needs to be added to the temperature-concentration correlation model: In the rectification section of the acidic water stripping unit 1, there is a clear negative correlation between ammonia concentration and temperature: wherever ammonia is concentrated, the gas phase temperature will be relatively low, or it will exhibit specific temperature difference characteristics. Using this physical property, a quantitative relationship between the axial temperature distribution and ammonia concentration distribution in the tower can be established through experiments or process simulations.

[0063] In this embodiment, the temperature-concentration correlation model adopts piecewise linear interpolation or table lookup method. That is, under multiple typical operating conditions (such as 50%, 75%, 100%, and 120% load), the steady-state temperature value of each temperature sensor location and the corresponding peak ammonia concentration position at the height are recorded in advance to establish a correspondence table between temperature gradient characteristics (such as temperature difference between adjacent temperature measurement points and overall temperature difference between the top and bottom of the tower) and concentration peak offset. During operation, the central control unit quickly estimates the axial position of the current ammonia enrichment zone in the tower by using table lookup and linear interpolation based on the measured temperature gradient.

[0064] Before the system is put into operation, obtain the model parameters using the following methods: On-site calibration: After stable operation under the design load, a portable gas analyzer is used to sample and analyze the ammonia concentration at different heights inside the tower, plot the concentration distribution curve, determine the reference position, and then change the load and stripping steam volume, record multiple sets of data to establish the corresponding relationship.

[0065] Process simulation: A mechanism model of the acidic water stripping tower is established using process simulation software (such as AspenPlus and HYSYS). Temperature-concentration data under different operating conditions are generated through sensitivity analysis to construct the model.

[0066] Furthermore, to avoid model drift, the system is also equipped with a long-cycle calibration loop. That is, whenever the air extraction component moves to the estimated position and runs stably for 30-60 minutes, the central control unit reads the measured ammonia concentration at the outlet of the ammonia buffer tank 45 and compares it with the theoretical concentration predicted by the model. If the deviation exceeds the preset allowable range (such as ±5%), the correction bias term in the model is automatically corrected to make subsequent predictions more accurate.

[0067] When both ammonia escape and ammonia concentration are within the normal range, the central control unit further acquires feedback signals from the liquid level detection unit and calculates the liquid level change rate. When the liquid level change rate exceeds the preset liquid level threshold (calculated based on the effective volume of the ammonia buffer tank 45 and the downstream consumption rate), it means that the ammonia production rate is seriously unbalanced with the consumption rate of the downstream ammonium sulfate preparation unit 3, which may lead to overflow or evacuation of the buffer tank, affecting the continuous operation of the system. The central control unit sends a control command to the negative pressure adjustment unit 5 to adjust the negative pressure value. By fine-tuning the opening of the adjustment valve 52, the negative pressure is changed to match the ammonia production rate with the downstream consumption. During this adjustment process, the central control unit still monitors the ammonia escape and ammonia concentration signals. If a higher priority abnormality occurs, the current adjustment is immediately interrupted.

[0068] Under the premise that ammonia escape, ammonia concentration, and liquid level change rate are all normal, the central control unit finally enters the stage of graded control based on sulfur dioxide concentration. It should be noted that, in order to avoid mutual interference of the flow field in the tower caused by the simultaneous adjustment of multiple adjustable gas extraction components, the central control unit is configured with a master-slave control mode. That is, under normal operation, only one master gas extraction component is subject to closed-loop position control, and the other gas extraction components are kept in a locked position or in a closed state. Only when the main gas extraction component is adjusted to the limit position (i.e., moved to the upper or lower end point) and the sulfur dioxide concentration still has not dropped to the target range, will a slave gas extraction component be activated in sequence, and the original master component will be switched to a fixed mode. After the flow field in the tower stabilizes again (for example, after stabilizing for 10-20 minutes), the position of the newly activated component will be adjusted. During the period of flow field stabilization, the system temporarily keeps the original position of the main gas extraction component unchanged, and only appropriately increases the negative pressure value through the negative pressure adjustment unit 5 to maintain the desulfurization effect. After stabilization, the position adjustment of the slave components will be performed.

[0069] When the sulfur dioxide concentration exceeds the preset threshold range, the central control unit sends a control command to the negative pressure regulating unit 5 to adjust the negative pressure value or sends a control command to the air extraction component 41 to adjust the position based on the temperature gradient. The preset threshold range includes at least three preset thresholds.

[0070] The preset threshold range for sulfur dioxide concentration includes a first preset threshold, a second preset threshold, and a third preset threshold. The first, second, and third preset thresholds are set progressively according to the national sulfur dioxide emission standards and the system's allowable fluctuation range.

[0071] When the sulfur dioxide concentration exceeds the first preset threshold but does not exceed the second preset threshold, the central control unit sends a first control command to the negative pressure adjustment unit 5 to adjust the negative pressure value to the first target range. Within this range, the extraction component 41 mainly relies on the gas collection hood 411 to extract ammonia-rich gas from the tower wall area. Since the deviation is slight, the desulfurization requirements can be met by simply adjusting the negative pressure, without changing the extraction position or starting the central drainage of the tower.

[0072] When the sulfur dioxide concentration exceeds the second preset threshold but does not exceed the third preset threshold, the central control unit sends a second control command to the negative pressure regulating unit 5 to raise the negative pressure value to the second target range. Within this range, the sliding ring 61 gradually overcomes the constraint force of the first elastic element 64 and slides into the fixed tube 63 under the action of negative pressure suction. The overlapping area of ​​the multiple filter holes 62 opened on it and the through holes 445 on the side wall of the throat 444 gradually increases with the increase of negative pressure, so as to achieve a smooth increase in the flow rate at the center of the tower, and switch the ammonia extraction range from extraction in the tower wall area to coordinated extraction in the tower wall area and the tower center area.

[0073] When the sulfur dioxide concentration feedback signal exceeds the third preset threshold, or when the sulfur dioxide concentration feedback signal still does not drop below the second preset threshold within the first time threshold (which can be set according to the system response characteristics, for example, 5-15 minutes) after the execution of the second control command, it indicates that relying solely on negative pressure regulation can no longer meet the desulfurization requirements. At this time, the central control unit sends a position adjustment command based on the temperature gradient to the extraction component 41: First, it re-estimates the axial position of the ammonia enrichment zone based on the real-time data of multiple temperature sensors, and then drives the gas collection hood 411 to move along the tower axis to the estimated position. During the movement, the system continuously monitors the change in sulfur dioxide concentration. If the concentration begins to decrease, it indicates that the direction of movement is correct. Continue to move to the estimated position and lock it. If the sulfur dioxide concentration rises after the movement, the system makes a reverse fine adjustment according to the preset offset until the concentration drops to the target range or reaches the movement limit. When an effective position is found, the system starts a new round of cyclic judgment from the ammonia escape signal to ensure that all parameters are always under control.

[0074] In summary, by setting up the central control unit, detection unit, air extraction component 41 and diameter reducing component 44, the problem of dynamic deviation in ammonia concentration distribution caused by upstream operating condition fluctuations in the acidic water stripping unit 1 is effectively solved, ensuring that the air extraction component 41 can always be aligned with the ammonia-rich area, thus ensuring the stability of ammonia water quality and the consistency of downstream desulfurization effect.

[0075] Furthermore, by setting multiple temperature sensors along the axial direction in the rectification section, the location of the ammonia enrichment zone is predicted in real time using the temperature gradient, overcoming the shortcomings of traditional ammonia concentration detection lag (5-20 minutes), and realizing rapid and accurate adjustment of the position of the extraction component. At the same time, a master-slave control mode is adopted, and the position of a single main extraction component is adjusted during normal operation, avoiding mutual interference of the flow field caused by the simultaneous operation of multiple adjustable components, and ensuring the reliability of the extraction component position adjustment method.

[0076] In addition, the passive flow-guiding characteristics of the variable diameter component 44 structure enable the system to automatically expand the extraction range under high load conditions. Without adding active moving parts and additional detection instruments, it achieves on-demand capture of high-concentration ammonia gas at the center of the tower, significantly improving ammonia resource recovery efficiency and energy utilization efficiency. Ultimately, while ensuring stable and compliant emissions of sulfur dioxide and ammonia escape, the entire system efficiently transforms waste ammonia and sulfur-containing pollutants that originally required complex treatment into high-value ammonium sulfate fertilizer products. This transforms environmental protection facilities from a simple cost center into a benefit center with economic benefits, achieving the unity of coordinated pollutant treatment and resource recycling.

[0077] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A sulfur tail gas resource utilization treatment system, characterized in that, It includes an acidic water stripping unit (1), a sulfur tail gas treatment unit (2), and an ammonium sulfate preparation unit (3), and also includes: Ammonia water conveying unit (4) is connected between the acidic water stripping device (1) and the sulfur tail gas treatment unit (2) to convert the ammonia-rich gas produced by the acidic water stripping device (1) into ammonia water and convey it to the sulfur tail gas treatment unit (2). The ammonia water conveying unit (4) includes an air extraction component (41) that is disposed inside the acidic water stripping device (1) and whose position is adjustable. The ammonia water delivery unit (4) also includes at least two side-line ammonia extraction pipes (42), which are located at different heights of the acidic water stripping device (1). The negative pressure regulating unit (5) is connected to the ammonia water delivery unit (4) to regulate the negative pressure of ammonia extraction; The detection unit includes a sulfur dioxide concentration monitor installed at the outlet of the sulfur tail gas treatment unit (2); The central control unit is electrically connected to the ammonia delivery unit (4), the negative pressure adjustment unit (5) and the detection unit respectively. The central control unit is used to receive the feedback signal from the detection unit and adjust the position of the air extraction component (41) or the negative pressure value of the negative pressure adjustment unit (5) according to the preset control strategy.

2. The sulfur tail gas resource utilization system according to claim 1, characterized in that, The number of the extraction components (41) is the same as the number of the side-line ammonia extraction pipes (42) and they correspond one-to-one.

3. The sulfur tail gas resource utilization system according to claim 2, characterized in that, The gas extraction assembly (41) includes a gas collection hood (411) with an arc-shaped plate structure, and its arc is consistent with the arc of the inner wall of the acidic water stripping device (1). The gas collection hood (411) is slidably connected to the acidic water stripping device (1). A cavity (412) is opened inside the gas collection hood (411). A plurality of gas extraction holes (413) facing the center of the acidic water stripping device (1) are opened on one side of the cavity (412). A connecting pipe (414) communicating with the cavity (412) is provided between the gas collection hood (411) and the side ammonia extraction pipe (42). A telescopic pipe (415) is provided at the connection end of the connecting pipe (414) and the side ammonia extraction pipe (42). A drive mechanism (43) is fixedly installed on one side of the gas extraction assembly (41). The drive mechanism (43) is fixedly connected to the side-line ammonia extraction pipe (42) and the connecting pipe (414) respectively, and is used to drive the connecting pipe (414) and the gas collection hood (411) to move up and down along the axis of the acidic water stripping device (1).

4. The sulfur tail gas resource utilization system according to claim 3, characterized in that, The connecting pipe (414) is provided with a reducing member (44) inside. The reducing member (44) includes an annular plate (441) fixedly connected to the inner wall of the connecting pipe (414). The annular plate (441) includes a contraction section (442) near the gas collecting hood (411) and an expansion section (443) near the telescopic pipe (415). A throat (444) is formed between the expansion section (443) and the contraction section (442). A through hole (445) communicating with the inside of the acidic water stripping device (1) is provided on the side wall of the throat (444).

5. The sulfur tail gas resource utilization system according to claim 4, characterized in that, An adjustment mechanism (6) is provided inside the through hole (445), which includes: A sliding ring (61) is slidably connected to the circumferential side of the connecting pipe (414), and the sliding ring (61) is provided with a plurality of filter holes (62) that match the through hole (445). A fixed tube (63) is sleeved on one side of a sliding ring (61) and fixedly connected to a connecting tube (414). One end of the sliding ring (61) extends into the fixed tube (63) and is slidably connected to the fixed tube (63). A first elastic element (64) is provided between the sliding ring (61) and the fixed tube (63). A through groove (66) penetrating the throat (444) is provided on the outer wall of the connecting tube (414). The sliding ring (61) divides the interior of the fixed tube (63) to form a sealing cavity (65). The sealing cavity (65) is connected to the throat (444) through the through groove (66). An annular baffle (67) is provided on the other side of the sliding ring (61) and fixedly connected to the connecting pipe (414). An opening is provided on one side of the annular baffle (67) for the sliding ring (61) to pass through.

6. The sulfur tail gas resource utilization system according to claim 2, characterized in that, The negative pressure regulating unit (5) includes: A negative pressure tank (51) is connected to each of the aforementioned side-line ammonia extraction pipelines (42); An air extraction device, which is connected to the negative pressure tank (51); The number of regulating valves (52) is the same as that of the side-line ammonia extraction pipes (42) and they are respectively installed on the corresponding side-line ammonia extraction pipes (42). The regulating valves (52) are electrically connected to the central control unit.

7. The sulfur tail gas resource utilization system according to claim 1, characterized in that, The ammonia water delivery unit (4) also includes an ammonia water buffer tank (45) for temporarily storing ammonia water formed by the condensation of ammonia gas; Multiple temperature sensors are arranged axially in the rectification section of the acidic water stripping device (1). The detection unit also includes an online ammonia escape monitor installed at the outlet of the sulfur tail gas treatment unit (2), an ammonia concentration monitor installed on the ammonia water delivery pipeline, and a liquid level detection unit installed inside the ammonia water buffer tank (45). The central control unit is equipped with a sequence determination module, which sequentially determines the ammonia escape feedback signal, the temperature sensor feedback signal, the liquid level change rate feedback signal, and the sulfur dioxide concentration feedback signal, and executes the corresponding control command according to the determination result. In the process of sequential determination, when any feedback signal triggers its corresponding control command, the sequence determination module stops determining the subsequent feedback signals.

8. The sulfur tail gas resource utilization system according to claim 7, characterized in that, The control instructions executed by the sequence determination module based on different feedback signals include: When the ammonia escape value exceeds the preset threshold, the central control unit sends a control command to the negative pressure regulating unit (5) to reduce the negative pressure value; When the ammonia concentration is lower than the preset concentration threshold, the central control unit calculates the axial temperature gradient inside the tower based on the real-time feedback of the multiple temperature sensors, and estimates the axial position of the ammonia enrichment zone based on the preset temperature-concentration correlation model. It then sends a control command to the extraction component (41) to move to the estimated position, and uses the feedback value of the ammonia concentration monitor for long-term calibration of the temperature-concentration correlation model. When the rate of change of liquid level exceeds the preset liquid level threshold, the central control unit sends a control command to the negative pressure adjustment unit (5) to adjust the ammonia water production to match the downstream consumption. When the sulfur dioxide concentration exceeds the preset threshold range, the central control unit sends a control command to the negative pressure regulating unit (5) to adjust the negative pressure value or sends a control command to the air extraction component (41) to adjust the position based on the temperature gradient. The preset threshold range includes at least three preset thresholds. The central control unit is configured in master-slave control mode. In normal operation, only one main air extraction component (41) is adjusted in position, while the other air extraction components (41) are kept locked or in the off state.

9. A sulfur tail gas resource utilization system according to claim 8, characterized in that, The preset threshold range for sulfur dioxide concentration includes a first preset threshold, a second preset threshold, and a third preset threshold; When the sulfur dioxide concentration exceeds the first preset threshold but does not exceed the second preset threshold, the central control unit sends a first control command to the negative pressure adjustment unit (5) to adjust the negative pressure value to the first target range. When the sulfur dioxide concentration exceeds the second preset threshold but does not exceed the third preset threshold, the central control unit sends a second control command to the negative pressure regulating unit (5) to raise the negative pressure value to the second target range, so that the ammonia extraction range is switched from extraction in the tower wall area to extraction in the tower wall area and tower center area in a coordinated manner. When the feedback signal exceeds the third preset threshold, or when the sulfur dioxide concentration feedback signal still does not drop below the second preset threshold within the first time threshold after the execution of the second control command, a command for position adjustment based on temperature gradient is issued to the extraction component (41) to find an extraction area with higher ammonia concentration.

10. A sulfur tail gas resource utilization system according to claim 1, characterized in that, The inlet end of the ammonia water conveying unit (4) is connected to the ammonia-rich gas outlet of the acidic water stripping device (1), and the outlet end is connected to the ammonia water inlet of the sulfur tail gas treatment unit (2). It is used to convert the ammonia-rich gas produced by the acidic water stripping device (1) into ammonia water and supply it to the sulfur tail gas treatment unit (2) as a desulfurization absorbent. The ammonium sulfate preparation unit (3) includes an oxidation reactor and a post-treatment unit. The slurry outlet of the sulfur tail gas treatment unit (2) is connected to the inlet of the oxidation reactor of the ammonium sulfate preparation unit (3) to oxidize the ammonium sulfite solution generated by desulfurization into an ammonium sulfate solution, and convert the ammonium sulfate solution into solid ammonium sulfate through the post-treatment unit at the end of the oxidation reactor.

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