Flue gas desulfurization device and use method thereof
By optimizing the labyrinth design and multiple mass transfer processes of the flue gas desulfurization device, the problem of low mass transfer efficiency when the flue gas flow rate varies over a large range was solved, and a highly efficient flue gas desulfurization effect was achieved.
Patent Information
- Application Number
- CN202610125355.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-01-29
- Publication Date
- 2026-03-06
AI Technical Summary
In existing technologies, when the flue gas flow rate varies over a large range, the nozzles are prone to being idle or accumulating liquid, resulting in low mass transfer efficiency. Furthermore, labyrinth treatment methods have failed to effectively solve the problem of accumulating liquid.
By coupling changes in flue gas direction, increases in desulfurization liquid flow rate, and rising liquid layer, the labyrinth design is optimized to form multiple mass transfer processes, including primary mass transfer, reverse secondary mass transfer, and re-mass transfer. Multiple contacts between flue gas and desulfurization liquid are achieved by utilizing the diversion and concentration barrier section and the vertical flue gas channel.
It improves the efficiency of desulfurization liquid utilization, enhances mass transfer efficiency under high flow conditions, reduces flue gas rise velocity, and improves flue gas treatment effect.
Smart Images
Figure CN121607010A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of flue gas treatment technology, specifically to a flue gas desulfurization device and its usage method. Background Technology
[0002] The amount of flue gas generated is often related to the operation of production equipment. The amount of flue gas generated varies depending on the operating parameters, process methods, and process steps of the production equipment. At the same time, the products produced also affect the operating parameters and process methods of the equipment. Therefore, the amount of flue gas generated is actually dynamic.
[0003] Algorithms have now been widely adopted in the manufacturing industry. They allow for the adjustment of desulfurization liquid spraying based on flue gas flow rate, dynamically matching the flow rate with the liquid usage. However, adjusting the number of desulfurization liquid nozzles can be problematic in environments with large flue gas flow variations. A large number of nozzles may become idle, while nozzles with limited flow are prone to ash accumulation and blockage due to the lack of water flow. While adjusting the nozzle spray velocity can increase the flow rate, the gas-liquid mass transfer channels often involve labyrinthine processes. Large amounts of water droplets can easily accumulate on these labyrinthine surfaces, leading to a significant reduction in subsequent mass transfer efficiency. Summary of the Invention
[0004] The purpose of this invention is to provide a flue gas desulfurization device and its usage method. This technical solution couples the changes in flue gas direction, the increase in desulfurization liquid flow rate, and the rise of the liquid accumulation layer. At the same time, it optimizes the labyrinth design to form flue gas energy reduction and multiple mass transfer, so as to solve the problems mentioned in the background art.
[0005] To achieve the above objectives, the present invention provides the following technical solution: A flue gas desulfurization device includes a desulfurization tower and a sprayer installed at the top of the desulfurization tower. The flue gas inlet flow rate of the desulfurization tower and the liquid inlet flow rate of the sprayer are both controlled by a flow regulation module. The side of the desulfurization tower is provided with a bottom discharge pipeline and a top discharge pipeline from bottom to top. A lifting flue gas pipe is slidably connected to the bottom of the desulfurization tower. A liquid pusher plate is fixedly connected to the periphery of the lifting flue gas pipe. The top of the lifting flue gas pipe is sealed by an arc apex. Multiple rotating pipe ports are rotatably connected to the side of the lifting flue gas pipe. The rotating pipe ports are connected to the side groove of the lifting flue gas pipe through a flexible flue gas cylinder. When the lifting flue gas pipe moves upward, the liquid pusher plate is located between the bottom row pipe and the top row pipe, and the opening direction of the rotating pipe ports is rotated to vertically downward. When the lifting flue gas pipe moves downward, the liquid pusher plate is located on the bottom surface of the desulfurization tower, and the opening direction of the rotating pipe ports is parallel to the horizontal line.
[0006] As a further embodiment of the present invention: the inner wall of the desulfurization tower is fixedly connected with a diversion and concentration obstruction section, the two ends of the diversion and concentration obstruction section are conical openings, and there is a flue gas passage between the two conical openings.
[0007] As a further embodiment of the present invention: a top-side inclined liquid channel is provided between the upper inclined surface of the diversion and concentration obstruction section and the side of the flue gas channel. The two ends of the top-side inclined liquid channel are the top opening and the side opening of the channel, respectively. The top opening and the side opening of the channel are located on the same radial line of the desulfurization tower, and one top-side inclined liquid channel is distributed on each radial line of the desulfurization tower.
[0008] As a further embodiment of the present invention: a plurality of vertical flue gas channels are provided on the bottom surface of the diversion and concentration barrier section, which are distributed axially and perpendicular to the top inclined liquid channel, and the diameter of the vertical flue gas channel is smaller than the diameter of the top inclined liquid channel. The vertical flue gas channel penetrates the bottom surface of the diversion and concentration barrier section through the bottom opening of the channel, and the other end of the vertical flue gas channel is connected to the top inclined liquid channel.
[0009] As a further embodiment of the present invention: the end of the top row pipeline near the desulfurization tower is sealed by a buoyancy valve plate, and the float of the buoyancy valve plate is higher than the top row pipeline.
[0010] As a further embodiment of the present invention: when the lifting flue gas pipe rises to its limit position and the opening of the rotating pipe is vertically downward, the bottom surface of the rotating pipe is higher than the highest point of the rotation of the buoyancy valve plate.
[0011] As a further embodiment of the present invention: a lifting mechanism is provided below the desulfurization tower, and the lifting mechanism drives the lifting flue gas pipe to slide vertically between the desulfurization tower and the bend.
[0012] As a further embodiment of the present invention: a side rod is fixedly connected to the inner wall of the desulfurization tower, and when the liquid pusher plate contacts the desulfurization tower, the side rod contacts the movable end of the rotating pipe.
[0013] As a further aspect of the present invention: a method of using a flue gas desulfurization device, comprising: When the flue gas flow rate and desulfurization liquid flow rate continue to increase, the lifting flue gas pipe is raised by the lifting mechanism. The rotating pipe port is released from the side rod limit and rotates 90 degrees under the influence of gravity. The flue gas is transported downwards, and the liquid pusher plate is raised to the space between the bottom and top pipes. The top pipe is closed by the buoyancy valve plate. The desulfurization liquid dripping from above accumulates below to form a liquid level until it exceeds the limit liquid level. The buoyancy valve plate opens, the liquid level is controlled, and the flue gas is discharged through the flexible flue gas cylinder and the rotating pipe port. The flue gas comes into contact with the surface of the used desulfurization liquid to form a primary mass transfer, which increases the utilization efficiency of the desulfurization liquid and reduces the sulfur content in the rising flue gas. At the same time, the kinetic energy of the flue gas emission is lost due to contact with the liquid, which reduces the speed of flue gas rise, increases the residence time, and improves the flue gas treatment effect. As the desulfurization liquid injection flow rate increases, the atomized droplets are more likely to agglomerate and form accumulated liquid flow when they contact the inclined surface of the diversion and concentration barrier section. At this time, part of the accumulated liquid flow enters the top inclined liquid channel through the top opening of the channel. The accumulated liquid flow rate is large, and the fluid is more likely to flow through the vertical flue gas channel port to the side opening of the channel and then out through the side opening. The accumulated liquid flow that flows out through the side opening of the channel enters the flue gas channel of the diversion and concentration barrier section along the inner wall of the flue gas channel of the diversion and concentration barrier section or in a parabolic trajectory. At this time, the accumulated liquid flow and the flue gas in the flue gas channel will contact and transfer mass again. When some flue gas enters the vertical flue gas channel through the bottom opening of the channel, it moves upward along the top inclined liquid channel under the influence of gravity. After the flue gas undergoes a reverse secondary mass transfer in the top inclined liquid channel and / or the vertical flue gas channel, it rises and undergoes a second mass transfer with the atomized droplets sprayed by the sprayer. A total of at least three mass transfers are carried out, and the multiple mass transfers of the desulfurization liquid improve the efficiency of its use.
[0014] Compared with the prior art, the beneficial effects of the present invention are: This technical solution couples the changes in flue gas direction, the increase in desulfurization liquid flow rate, and the rise of the liquid accumulation layer. This allows the high-flow-rate flue gas to first undergo mass transfer with the desulfurization liquid in the liquid accumulation layer, which has undergone multiple mass transfers, and absorb the kinetic energy of the flue gas, thus reducing the upward velocity of the flue gas and allowing for subsequent mass transfer. Meanwhile, the increase in the desulfurization liquid flow rate and the change in the liquid collection method at the bottom of the desulfurization tower accelerate the formation of the liquid accumulation layer, improving the utilization efficiency of the desulfurization liquid and increasing the utilization efficiency of the desulfurization liquid under high flow conditions.
[0015] Furthermore, based on the aforementioned lateral dispersion of flue gas, a labyrinth structure is added. This addresses the mass transfer problem caused by the accumulation of liquid in the high-flow-rate desulfurization liquid on the labyrinth structure surface. The accumulated liquid can transfer mass with the flue gas in the flue gas channel through the top inclined surface of the diversion and concentration barrier section and the side opening of the channel. A portion of the flue gas undergoes counter-current mass transfer in the vertical flue gas channel and the top inclined liquid channel, significantly improving mass transfer efficiency and thus further enhancing the utilization efficiency of the desulfurization liquid. Attached Figure Description
[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0017] Figure 1 This is a schematic cross-sectional view of a flue gas desulfurization device. Figure 2 This is a schematic diagram showing two liquid level states in a flue gas desulfurization device. Figure 3 This is a top view schematic diagram of a diversion and concentration obstruction section in a flue gas desulfurization device; Figure 4 This is a schematic diagram of the structure of a flue gas desulfurization device with a rising flue gas pipe. In the diagram: 1. Desulfurization tower; 11. Sprayer; 12. Side rod; 2. Diversion and concentration obstruction section; 21. Top and side inclined liquid channel; 211. Top opening of the channel; 212. Side opening of the channel; 22. Vertical flue gas channel; 221. Bottom opening of the channel; 3. Bottom row pipeline; 4. Top row pipeline; 41. Buoyancy valve plate; 5. Lifting flue gas pipe; 51. Rotating pipe opening; 52. Flexible flue gas stack; 53. Lifting mechanism; 54. Liquid pusher plate; 55. Arc top. Detailed Implementation
[0018] Please see Figures 1-4 In this embodiment, to address the issue of low mass transfer efficiency caused by increased desulfurization liquid flow rate, the following improvements are made: The improvements include: a desulfurization tower 1 and a sprayer 11 installed on top of the desulfurization tower 1. The flue gas flow rate of the desulfurization tower 1 and the liquid flow rate of the sprayer 11 are both controlled by a flow regulation module. The sides of the desulfurization tower 1 are provided with a bottom drain pipe 3 and a top drain pipe 4 from bottom to top. A lifting flue gas pipe 5 is slidably connected to the bottom of the desulfurization tower 1. A liquid pusher plate 54 is fixedly connected to the periphery of the lifting flue gas pipe 5. The top of the lifting flue gas pipe 5 is sealed by an arc apex 55. Multiple rotating pipe ports 51 are rotatably connected to the sides of the lifting flue gas pipe 5. The number of rotating pipe ports 51 can be 2, 3, 4, 5, etc. If the lifting flue gas pipe 5 is annular, the multiple rotating pipe ports 51 are distributed at equal angles along the axis. If the lifting flue gas pipe 5 is polyhedral, the number of rotating pipe ports 51 corresponds to the number of the periphery of the lifting flue gas pipe 5. The rotating nozzle 51 is connected to the side trough of the lifting flue gas pipe 5 through the flexible flue gas cylinder 52. When the lifting flue gas pipe 5 moves upward, the pusher plate 54 is located between the bottom pipe 3 and the top pipe 4, and the opening direction of the rotating nozzle 51 is rotated to vertically downward. When the lifting flue gas pipe 5 moves downward, the pusher plate 54 is located at the bottom of the desulfurization tower 1, and the opening direction of the rotating nozzle 51 is parallel to the horizontal line. The inner wall of the desulfurization tower 1 is fixedly connected with a side rod 12. When the pusher plate 54 contacts the desulfurization tower 1, the side rod 12 contacts the movable end of the rotating nozzle 51.
[0019] After the improvement, when the flue gas volume and the desulfurization liquid spray volume are both low, the lifting flue gas pipe 5 is at its lowest point, the liquid pusher plate 54 is in contact with the desulfurization tower 1, and the desulfurization liquid descends to the liquid pusher plate 54 after contacting the flue gas, and is discharged through the bottom discharge pipe 3 for secondary treatment of the desulfurization liquid.
[0020] When both flue gas volume and desulfurization liquid spray volume are high, the lifting flue gas pipe 5 is driven to rise by the lifting mechanism 53. The lifting flue gas pipe 5 slides vertically between the desulfurization tower 1 and the bend. After the lifting flue gas pipe 5 rises, the movable part of the rotating pipe port 51 is released from the restriction of the side rod 12 and descends and rotates to 90 degrees under the influence of gravity. The angle range can be controlled by the vertical distance between the rotating pipe port 51 and the side rod 12 or by the rotation structure of the rotating pipe port 51. If the rotating pipe port 51 is difficult to move by gravity, a torsion spring can be installed in the rotation structure. In this technical solution, the rotation structure of the rotating pipe port 51 and the lifting flue gas pipe 5 protrudes from the surface of the rotating pipe port 51. Therefore, an inclined block that contacts the side rod 12 is set above the frame of the rotating pipe port 51, so that the side rod 12 and the rotating pipe port 51 have a distance to avoid the rotation structure.
[0021] After the rotating nozzle 51 rotates, the flexible flue gas stack 52 extends under the influence of the rotation of the rotating nozzle 51. Figure 2With the pusher plate 54 raised, it gets closer to the rotating nozzle 51. Under the condition of high flow rate of desulfurization liquid, the liquid quickly forms a liquid level on the surface of the pusher plate 54. The initial kinetic energy of the flue gas acts on the liquid surface, and the liquid accumulation in the liquid level is the accumulated liquid after mass transfer. The accumulated liquid layer absorbs some of the sulfur in the flue gas, which improves the utilization efficiency of the desulfurization liquid.
[0022] Because the end of the top-flow pipe 4 closest to the desulfurization tower 1 is sealed by the buoyancy valve plate 41, and the float of the buoyancy valve plate 41 is higher than the top-flow pipe 4, when the rising and lowering flue gas pipe 5 rises to its limit position and the opening of the rotating pipe port 51 is vertically downward, the bottom surface of the rotating pipe port 51 is higher than the highest point of the rotation of the buoyancy valve plate 41. Therefore, when the buoyancy valve plate 41 drives the top-flow pipe 4 to connect with the desulfurization tower 1, the top-flow pipe 4 is always located below the liquid surface, preventing flue gas from being discharged through the top-flow pipe 4.
[0023] Secondly, to address the issue of liquid accumulation caused by increased desulfurization liquid spraying efficiency after the labyrinth treatment inside desulfurization tower 1, the following improvements are made: Improvements: A diversion and concentration obstruction section 2 is fixedly connected to the inner wall of the desulfurization tower 1. The two ends of the diversion and concentration obstruction section 2 are conical openings, and there is a flue gas passage between the two conical openings. A top-side inclined liquid passage 21 is opened between the upper inclined surface of the diversion and concentration obstruction section 2 and the side of the flue gas passage. The two ends of the top-side inclined liquid passage 21 are the top opening 211 and the side opening 212, respectively. Multiple vertical flue gas passages 22 are opened on the bottom surface of the diversion and concentration obstruction section 2, which are distributed axially and perpendicular to the top-side inclined liquid passage 21. The diameter of the vertical flue gas passage 22 is smaller than the diameter of the top-side inclined liquid passage 21. The vertical flue gas passage 22 penetrates the bottom surface of the diversion and concentration obstruction section 2 through the bottom opening 221. The other end of the vertical flue gas passage 22 is connected to the top-side inclined liquid passage 21.
[0024] After the improvement, a large amount of desulfurization liquid is located on the surface of the diversion and concentration barrier section 2. Droplets easily accumulate to form a liquid flow. Part of this liquid flow enters the flue gas channel of the diversion and concentration barrier section 2 and undergoes mass transfer with the flue gas. The other part of the liquid flow enters the top inclined liquid channel 21 through the top opening 211. The top inclined liquid channel 21 is inclined, and under the influence of gravity and inertia, a large amount of the liquid flow more easily passes through the vertical flue gas channel 22 and enters the middle flue gas channel through the side opening 212 for secondary mass transfer. A small amount of liquid flow descends with the vertical flue gas channel 22. Secondly, the riser flue gas pipe 5 opens to exhaust gas. When the flue gas rises through the inclined surface below the diversion and concentration barrier section 2, some of the flue gas enters the top inclined liquid channel 21 through the vertical flue gas channel 22. At this time, the flue gas undergoes counter-current mass transfer with the liquid flow in the top inclined liquid channel 21 and / or the vertical flue gas channel 22.
[0025] To increase the uniformity of distribution and avoid interference between the vertical flue gas channels 22, the top opening 211 and the side opening 212 of the channels are located on the same radial line of the desulfurization tower 1, and a top-side inclined liquid channel 21 is distributed on each radial line of the desulfurization tower 1, thereby avoiding interference between the vertical flue gas channels 22. Some of the vertically falling liquid is dispersed under the action of the arc apex 55.
[0026] The usage method is as follows: When the flue gas flow rate and desulfurization liquid flow rate continue to increase, the lifting flue gas pipe 5 is raised by the lifting mechanism 53, and the rotating pipe port 51 is released from the side rod 12 limit and rotates 90 degrees under the influence of gravity. The flue gas conveying direction is downward, and the liquid pusher plate 54 is raised to the space between the bottom discharge pipe 3 and the top discharge pipe 4. The top discharge pipe 4 is closed by the buoyancy valve plate 41, and the desulfurization liquid dripping from above accumulates below to form a liquid level until it exceeds the limit liquid level. Then the buoyancy valve plate 41 is opened, the liquid level is controlled, and the flue gas is discharged through the flexible flue gas cylinder 52 and the rotating pipe port 51. The flue gas comes into contact with the surface of the desulfurization liquid after use to form a mass transfer, which increases the utilization efficiency of the desulfurization liquid and reduces the sulfur content in the rising flue gas. At the same time, the kinetic energy of the flue gas emission is lost due to contact with the liquid, which reduces the speed of the flue gas rising, increases the residence time, and improves the flue gas treatment effect. As the desulfurization liquid injection flow rate increases, the atomized droplets are more likely to agglomerate and form an accumulated liquid flow when they contact the inclined surface of the diversion and concentration barrier section 2. At this time, part of the accumulated liquid flow enters the top inclined liquid channel 21 through the top opening 211 of the channel. The accumulated liquid flow rate is large, and the fluid is more likely to flow through the port of the vertical flue gas channel 22 to the side opening 212 of the channel, and then flow out through the side opening 212 of the channel. The accumulated liquid flow that flows out through the side opening 212 of the channel enters the flue gas channel of the diversion and concentration barrier section 2 along the inner wall of the flue gas channel or in a parabolic trajectory. At this time, the accumulated liquid flow and the flue gas in the flue gas channel will contact and transfer mass again. When some flue gas enters the vertical flue gas channel 22 through the bottom opening 221, it moves upward along the top inclined liquid channel 21 under the influence of gravity. After the flue gas undergoes a reverse secondary mass transfer in the top inclined liquid channel 21 and / or the vertical flue gas channel 22, it rises and undergoes a second mass transfer with the atomized droplets sprayed by the sprayer 11. A total of at least three mass transfers are performed, and the multiple mass transfers of the desulfurization liquid improve the efficiency of its use.
[0027] The above description is merely 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 flue gas desulfurization device, comprising a desulfurization tower (1) and a sprayer (11) arranged at the top of the desulfurization tower (1), the flue gas flow rate of the desulfurization tower (1) and the liquid flow rate of the sprayer (11) are regulated by a flow rate regulating module, characterized in that: The side of the desulfurization tower (1) is sequentially provided with a bottom exhaust pipe (3) and a top exhaust pipe (4) from bottom to top; The lower portion of the desulfurization tower (1) is slidably connected with a lifting flue gas pipe (5), the peripheral side of the lifting flue gas pipe (5) is fixedly connected with a liquid pushing plate (54), the top of the lifting flue gas pipe (5) is blocked by an arc top (55), the side of the lifting flue gas pipe (5) is rotatably connected with a plurality of rotating pipe mouths (51), the rotating pipe mouths (51) are in communication with the side groove of the lifting flue gas pipe (5) through flexible flue gas cylinders (52), when the lifting flue gas pipe (5) moves upward, the liquid pushing plate (54) is located between the bottom exhaust pipe (3) and the top exhaust pipe (4), and the opening direction of the rotating pipe mouths (51) is rotated to be perpendicular downward, when the lifting flue gas pipe (5) moves downward, the liquid pushing plate (54) is located on the bottom surface of the desulfurization tower (1), and the opening direction of the rotating pipe mouths (51) is parallel to the horizontal line.
2. A flue gas desulphurization device according to claim 1, characterized in that: The inner wall of the desulfurization tower (1) is fixedly connected with a shunt concentration obstacle (2), the two ends of the shunt concentration obstacle (2) are tapered openings, and the two tapered openings have a flue gas passage therebetween.
3. A flue gas desulphurization device according to claim 2, characterized in that: An upper inclined surface of the shunt concentration obstacle (2) and the side surface of the flue gas passage are provided with a top side inclined liquid passage (21), the two ends of the top side inclined liquid passage (21) are a passage top opening (211) and a passage side opening (212) respectively, the passage top opening (211) and the passage side opening (212) are located on the same radial line of the desulfurization tower (1), and one top side inclined liquid passage (21) is distributed on each radial line of the desulfurization tower (1).
4. A flue gas desulphurization device according to claim 3, characterized in that: A plurality of vertical flue gas passages (22) are provided on the bottom surface of the shunt concentration obstacle (2) and are distributed axially along the top side inclined liquid passage (21) and are perpendicular, the diameter of the vertical flue gas passage (22) is smaller than that of the top side inclined liquid passage (21), the vertical flue gas passage (22) penetrates the bottom surface of the shunt concentration obstacle (2) through a passage bottom opening (221), and the other end of the vertical flue gas passage (22) is in communication with the top side inclined liquid passage (21).
5. A flue gas desulphurization device according to claim 1, characterized in that: The end of the top exhaust pipe (4) close to the desulfurization tower (1) is closed by a buoyancy valve plate (41), and the height of the floating ball of the buoyancy valve plate (41) is higher than that of the top exhaust pipe (4).
6. A flue gas desulphurization device according to claim 5, characterized in that: When the lifting flue gas pipe (5) rises to the limit position and the opening of the rotating pipe mouth (51) is perpendicular downward, the bottom surface of the rotating pipe mouth (51) is higher than the highest point of the rotation of the buoyancy valve plate (41).
7. A flue gas desulphurization device according to claim 1, characterized in that: A lifting mechanism (53) is arranged below the desulfurization tower (1), the lifting mechanism (53) drives the lifting flue gas pipe (5) to vertically slide between the desulfurization tower (1) and the elbow pipe.
8. A flue gas desulphurization device according to claim 1, characterized in that: The inner wall of the desulfurization tower (1) is fixedly connected with a side rod (12), when the liquid pushing plate (54) contacts the desulfurization tower (1), the side rod (12) contacts the movable end of the rotating pipe mouth (51).
9. A method of using a flue gas desulphurization device according to any one of claims 1 to 8, characterized in that: The application relates to a desulfurization tower (1) and a desulfurization method thereof. When the flue gas flow and the desulfurization liquid flow continue to increase, the lifting mechanism (53) lifts the lifting flue gas pipe (5), the rotary pipe opening (51) is separated from the side rod (12) and is limited to rotate 90 degrees under the influence of gravity, the flue gas conveying direction is downward, the liquid pushing plate (54) is lifted to the bottom discharge pipe (3) and the top discharge pipe (4), the top discharge pipe (4) is closed by the buoyancy valve plate (41), the desulfurization liquid falling from the top is accumulated to form a liquid level below, until the limit liquid level is exceeded, the buoyancy valve plate (41) is opened, the liquid level is controlled, the flue gas is discharged through the flexible flue gas pipe (52) and the rotary pipe opening (51), the flue gas contacts the used desulfurization liquid to form primary mass transfer, which increases the use efficiency of the desulfurization liquid and reduces the sulfur content in the rising flue gas, and the kinetic energy of the flue gas emission is lost by contacting the liquid, which reduces the rising speed of the flue gas, increases the residence time, and improves the flue gas treatment effect; When the desulfurization liquid injection flow increases, the atomized liquid droplets are more likely to agglomerate and form accumulated liquid flow on the inclined surface of the flow concentration obstacle part (2). At this time, part of the accumulated liquid flow enters the top side inclined liquid channel (21) through the channel top opening (211), the accumulated liquid flow is large, and the fluid is more likely to flow to the channel side opening (212) through the vertical flue gas channel (22) port, and then flow out through the channel side opening (212). The accumulated liquid flow flowing out through the channel side opening (212) enters the flue gas channel of the flow concentration obstacle part (2) along the inner wall of the flue gas channel or a parabola, and at this time, the accumulated liquid flow contacts the flue gas in the flue gas channel again for mass transfer; When part of the flue gas enters the vertical flue gas channel (22) through the channel bottom opening (221), it moves upward along the top side inclined liquid channel (21) under the influence of gravity, and the flue gas forms reverse secondary mass transfer in the top side inclined liquid channel (21) and / or the vertical flue gas channel (22), and then rises and performs mass transfer with the atomized liquid droplets sprayed by the sprayer (11) again, a total of at least three times of mass transfer, and the multiple mass transfer of the desulfurization liquid improves the use efficiency.