Flue gas purification system

Abstract

The invention discloses a flue gas purification system, and relates to the technical field of chemical acid making equipment, and the flue gas purification system comprises a dynamic wave washing tower, a circulating pump, a settler and a high-level water tank; the dynamic wave washing tower comprises a tower body and a reverse spraying pipe, the reverse spraying pipe is communicated with the tower body, the reverse spraying pipe comprises a spraying head and an overflow groove, the overflow groove is located at the top of the reverse spraying pipe, and an overflow weir is arranged on the inner side wall of the overflow groove; the input end of the circulating pump is connected with the bottom of the tower body through a pipeline; the output end of the circulating pump is connected with the overflow groove and the spray header through pipelines; the settler is connected between the output end of the circulating pump and the bottom of the tower body through a pipeline, and the settler is provided with a settling drain outlet; the high-level water tank is connected with a water supplementing pipe, the bottom of the high-level water tank is connected with an overflow tank through a pipeline, and an emergency valve is arranged between the bottom of the high-level water tank and the overflow tank; the technical scheme provided by the invention aims to reduce system function decline caused by dust deposition.

Description

flue gas purification system Technical Field

[0001] This invention relates to the field of chemical acid production equipment technology, and in particular to a flue gas purification system. Background Technology

[0002] A scrubbing tower is a gas purification and treatment device. For example, a dynamic wave scrubbing tower (or dynamic wave scrubber) forms a stable foam zone through high-speed counter-current collision of gas and liquid phases, thereby achieving multiple functions such as rapid cooling, dust removal, desulfurization and dehydration of the gas.

[0003] In existing acid pretreatment purification processes, a circulating pump is typically used to pump a portion of the dilute acid (circulating washing liquid) into the overflow tank and emergency high-level water tank (also known as the high-level acid tank or emergency water tank) of the reverse nozzle. Pumping into the overflow tank allows for the recycling of the dilute acid while protecting the inner wall of the reverse nozzle. The emergency high-level water tank is designed to continue supplying water to the washing system using the gravitational potential energy of the tank in the event of a sudden power outage or malfunction of the circulating pump, preventing backflow or dry burning.

[0004] The problem with existing dynamic wave scrubbing tower scrubbers is that a large amount of dust (especially coke dust) in the flue gas is absorbed by the circulating scrubbing liquid. The circulating scrubbing liquid carries a large amount of dust into the overflow tank and emergency high-level tank of the reverse nozzle. However, the overflow tank and emergency high-level tank of the reverse nozzle are both located at high positions, making them inconvenient to handle. Coke dust easily settles and accumulates at the bottom of the tank, which reduces the protective function of the overflow tank on the inner wall of the pipe. The effective volume of the high-level tank is occupied by solid waste, which reduces or even eliminates the emergency water storage function of the high-level tank, posing a huge hidden danger to the safe operation of the system. Summary of the Invention

[0005] The main objective of this invention is to propose a flue gas purification system that aims to reduce the decline in system function caused by dust accumulation.

[0006] To achieve the above objectives, the present invention proposes a flue gas purification system comprising: a dynamic wave scrubbing tower, including a tower body and a backspray pipe, the backspray pipe being connected to the tower body, the backspray pipe including a spray head and an overflow trough, the overflow trough being located at the top of the backspray pipe, and the inner wall of the overflow trough being configured as an overflow weir; a circulating pump, the input end of the circulating pump being connected to the bottom of the tower body via a pipe, and the output end of the circulating pump being connected to the overflow trough and the spray head via a pipe; a settling device, connected via a pipe between the output end of the circulating pump and the bottom of the tower body, the settling device being provided with a settling discharge port; and an elevated water tank, the elevated water tank being connected to a water supply pipe, the bottom of the elevated water tank being connected to the overflow trough via a pipe, and an emergency valve being provided between the bottom of the elevated water tank and the overflow trough.

[0007] In one embodiment, the flue gas purification system further includes a flocculant dosing station, which is located on the pipeline between the input end of the circulating pump and the bottom of the tower.

[0008] In one embodiment, the water supply pipe is connected to the spray head via a pipeline, and a spray water supply valve is provided on the pipeline between the water supply pipe and the spray head.

[0009] In one embodiment, the reverse spray pipe includes a plurality of spray heads, wherein each spray head is connected to the output end of the circulating pump and the spray water supply valve arranged in parallel via a pipe; or, some of the spray heads are connected to the output end of the circulating pump via pipes, and other spray heads are connected to the spray water supply valve via pipes.

[0010] In one embodiment, the elevated water tank is connected to an overflow pipe, the overflow pipe is equipped with an overflow valve, and the overflow pipe is connected to the overflow tank.

[0011] In one embodiment, the overflow tank is provided with a plurality of water inlets, which are evenly distributed along the circumference of the overflow tank, and the output end of the circulation pump is connected to the plurality of water inlets arranged in parallel.

[0012] In one embodiment, an overflow vent is provided at the bottom of the overflow trough, the overflow vent is connected to a vent pipe, a vent valve is provided on the vent pipe, and the vent pipe is connected to the tower body.

[0013] In one embodiment, the reverse nozzle includes a settling hopper located at the bottom of the overflow trough, the bottom of the settling hopper is provided with an overflow drain port, the overflow drain port is connected to an overflow pipe, and the height of the overflow drain port is lower than the height of the overflow outlet.

[0014] In one embodiment, the reverse spray pipe includes an inner pipe and an outer pipe that are nested together. The inner pipe is connected to the tower body, and the overflow groove is defined between the outer pipe and the inner pipe. The overflow outlet is located at the bottom end of the outer pipe.

[0015] In one embodiment, a discharge pump is provided at the bottom of the overflow drain pipe.

[0016] This technical solution uses a circulating pump to connect the tower body, overflow tank, spray heads, and settling tank to achieve the circulation of the washing liquid. When flue gas enters the tower body, the circulating pump delivers the circulating washing liquid from the bottom of the tower body to the spray heads, where it is sprayed out to meet the flue gas flowing upwards towards the bottom of the reverse spray pipe. At the same time, the circulating washing liquid in the overflow tank continuously overflows through the overflow weir, forming a stable liquid film in the reverse spray pipe. This dual effect significantly increases the contact area and reaction time between the flue gas and the circulating washing liquid, achieving efficient desulfurization and dust removal, while also cooling the inner wall of the pipeline. The settling tank can perform solid-liquid separation of the circulating washing liquid, reducing dust blockage of the spray heads and overflow tank. Sewage is discharged through the settling drain, extending the normal operating cycle of the system. The emergency valve can be opened in case of circulating pump failure or pipeline blockage, replenishing the overflow tank with liquid through the high-level water tank to prevent the pipeline temperature from becoming too high. The dual-output structure, which connects the overflow tank and the spray head to the circulating pump respectively, can supply water to the overflow tank to form a stable water curtain of overflow weir for preliminary reverse spray washing of the rising flue gas, and can also supply high-pressure circulating washing liquid to the spray head for secondary spray purification. The dual-output structure enables multi-stage purification of flue gas and improves the capture efficiency of pollutants in the flue gas. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, 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 the structures shown in these drawings without creative effort.

[0018] Figure 1 is a structural schematic diagram of an embodiment of the flue gas purification system provided by the present invention; Figure 2 is a partial enlarged view of point A in Figure 1; Figure 3 is a structural schematic diagram of another embodiment of the flue gas purification system provided by the present invention; Figure 4 is a partial enlarged view of point B in Figure 3.

[0019] Reference numerals: 1. Dynamic wave scrubbing tower; 11. Tower body; 12. Backspray pipe; 121. Spray head; 122. Overflow trough; 1221. Overflow weir; 123. Settling hopper; 1231. Overflow outlet; 1232. Overflow pipe; 124. Inner pipe; 125. Outer pipe; 2. Circulating pump; 3. Pipeline; 4. Settler; 41. Settling outlet; 5. High-level water tank; 51. Water supply pipe; 52. Emergency valve; 6. Flocculant dosing station; 7. Spray water supply valve; 8. Overflow pipe; 81. Overflow valve; 9. Drain pipe; 91. Drain valve; 10. Discharge pump; 11a. Electric valve; 12a. Pressure tester.

[0020] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0021] 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 a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0022] It should be noted that if the embodiments of the present invention involve directional indicators (such as up, down, left, right, front, and back), the directional indicators are only used to explain the relative positional relationship and movement of the components in a specific posture. If the specific posture changes, the directional indicators will also change accordingly.

[0023] Furthermore, if the embodiments of this invention involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the use of "and / or" or "and / or" throughout the text includes three parallel solutions. For example, "A and / or B" includes solution A, solution B, or a solution where both A and B are satisfied simultaneously. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0024] A scrubbing tower is a gas purification and treatment device. For example, a dynamic wave scrubbing tower (or dynamic wave scrubber) forms a stable foam zone through high-speed counter-current collision of gas and liquid phases, thereby achieving multiple functions such as rapid cooling, dust removal, desulfurization and dehydration of the gas.

[0025] In existing acid pretreatment purification processes, a circulating pump is typically used to pump a portion of the dilute acid (circulating washing liquid) into the overflow tank and emergency high-level water tank (also known as the high-level acid tank or emergency water tank) of the reverse nozzle. Pumping into the overflow tank allows for the recycling of the dilute acid while protecting the inner wall of the reverse nozzle. The emergency high-level water tank is designed to continue supplying water to the washing system using the gravitational potential energy of the tank in the event of a sudden power outage or malfunction of the circulating pump, preventing backflow or dry burning.

[0026] The problem with existing dynamic wave scrubbing tower scrubbers is that a large amount of dust (especially coke dust) in the flue gas is absorbed by the circulating scrubbing liquid. The circulating scrubbing liquid carries a large amount of dust into the overflow tank and emergency high-level tank of the reverse nozzle. However, the overflow tank and emergency high-level tank of the reverse nozzle are both located at high positions, making them inconvenient to handle. Coke dust easily settles and accumulates at the bottom of the tank, which reduces the protective function of the overflow tank on the inner wall of the pipe. The effective volume of the high-level tank is occupied by solid waste, which reduces or even eliminates the emergency water storage function of the high-level tank, posing a huge hidden danger to the safe operation of the system.

[0027] Based on the above problems, this invention proposes a flue gas purification system.

[0028] Please refer to Figures 1 and 2. In one embodiment of the present invention, the flue gas purification system includes a dynamic wave scrubbing tower 1, a circulating pump 2, a settling tank 4, and an elevated water tank 5.

[0029] The dynamic wave scrubbing tower 1 includes a tower body 11 and a backspray pipe 12. The backspray pipe 12 is connected to the tower body 11 and includes a spray head 121 and an overflow trough 122. The overflow trough 122 is located at the top of the backspray pipe 12, and the inner wall of the overflow trough 122 is configured as an overflow weir 1221. The input end of the circulating pump 2 is connected to the bottom of the tower body 11 through a pipe 3, and the output end of the circulating pump 2 is connected to the overflow trough 122 and the spray head 121 through a pipe 3. The settling device 4 is connected between the output end of the circulating pump 2 and the bottom of the tower body 11 through a pipe 3, and the settling device 4 is provided with a settling discharge port 41. The elevated water tank 5 is connected to a water supply pipe 51, and the bottom output end of the elevated water tank 5 is connected to the overflow trough 122 through a pipe 3. An emergency valve 52 is provided between the bottom of the elevated water tank 5 and the overflow trough 122.

[0030] This technical solution uses a circulating pump 2 to connect the tower body 11, overflow trough 122, spray head 121, and settling tank 4 to achieve the circulation of the washing liquid. When the flue gas enters the tower body 11, the circulating pump 2 transports the circulating washing liquid at the bottom of the tower body 11 to the spray head 121 for spraying, forming a countercurrent contact with the flue gas flowing upwards towards the bottom of the reverse spray pipe 12. At the same time, the circulating washing liquid in the overflow trough 122 continuously overflows through the overflow weir 1221, forming a stable liquid film in the reverse spray pipe 12. This dual effect significantly improves the interaction between the flue gas and the washing liquid. The contact area and reaction time of the circulating washing liquid achieve efficient desulfurization and dust removal, while also cooling the inner wall of pipe 3. The settling tank 4 separates the circulating washing liquid into solid and liquid components, reducing dust blockage of spray heads 121 and overflow tank 122. Sewage is discharged through the settling outlet 41, extending the system's normal operating cycle. The emergency valve 52 can be opened in case of a failure of the circulating pump 2 or blockage of pipe 3, replenishing liquid to the overflow tank 122 through the high-level water tank 5 to prevent excessive temperature in pipe 3. The dual-output structure, with the circulating pump 2 connected to both the overflow tank 122 and the spray heads 121, allows for both water supply to the overflow tank 122 to form a stable water curtain for initial reverse spray washing of the rising flue gas, and high-pressure circulating washing liquid to the spray heads 121 for secondary spray purification. This dual-output system achieves multi-stage purification of the flue gas, improving the capture efficiency of pollutants in the flue gas.

[0031] In the specific implementation process, the power wave scrubbing tower 1 and the pipeline 3 can be made of fiberglass or carbon steel and lined with wear-resistant and corrosion-resistant rubber or graphite bricks to adapt to the high temperature and high corrosion flue gas environment; the overflow weir 1221 of the reverse spray pipe 12 can be set as a sawtooth structure or a flat shape to achieve the required overflow effect; the settling tank 4 can be an inclined tube settling tank 4 or an inclined plate settling tank 4, which can make the dust particles in the circulating washing liquid settle quickly. The settled dust can be discharged periodically through the settling drain port 41, for example, once every 24 hours for 30 minutes each time; the emergency valve 52 can be at least one of an electric automatic control valve and a manual valve. The electric automatic control valve can be linked with the operating status of the circulating pump 2. When the shutdown signal of the circulating pump 2 is detected, the emergency valve 52 is controlled to open, and the circulating washing liquid in the high-level water tank 5 is then replenished into the overflow tank 122. Flow regulating valves can be installed on the pipes 3 leading from the circulating pump 2 to the overflow tank 122, the pipes 3 leading from the circulating pump 2 to the spray head 121, and the pipes 3 leading from the circulating pump 2 to the settling tank 4. The valve openings are adjusted according to the flue gas volume to maintain stable overflow from the overflow weir 1221 and spraying from the spray head 121. A pressure tester 12a can be installed on the pipe leading to the spray head 121 to monitor the spray pressure in real time and provide feedback to adjust the output power of the circulating pump 2. For example, when treating high-concentration flue gas, the spray pressure can be appropriately increased to enhance the washing effect. The installation height of the elevated water tank 5 should be higher than that of the overflow tank 122 to ensure sufficient water pressure to form a stable water flow, or a separate water pump can be installed to provide water pressure. The outlet end of the settling tank 4, in addition to connecting to the bottom of the tower body 11, can also be connected to a primary packed tower and a desorption tower. The settling discharge port 41 is connected to the concentrated phase tank. An outlet is provided at the top of the tower body 11, connected to the primary packed tower.

[0032] In one embodiment, the flue gas purification system further includes a flocculant dosing station 6, which is located on the pipe 3 between the input end of the circulating pump 2 and the bottom of the tower body 11.

[0033] This technical solution arranges the flocculant injection station 6 on the pipeline 3 between the output end of the circulating pump 2 and the bottom of the tower body 11. This allows the circulating pump 2 to enhance the mixing effect of the circulating washing liquid and the flocculant, enabling the flocculant to be fully stirred and dispersed to the overflow tank 122, the settling tank 4, and the bottom of the tower body 11. This connection allows the flocculant to fully contact and combine with the dust in the liquid, forming larger flocs, which greatly improves the efficiency of subsequent sedimentation and separation. At the same time, it avoids the problem of uneven local concentration and waste of reagents caused by directly injecting the flocculant into the tower body 11. Furthermore, the mixing effect is enhanced by the conveying power of the circulating pump 2, further optimizing the overall treatment capacity of flue gas purification.

[0034] In the specific implementation process, manual dosing or screw-type flocculant dosing pump can be selected as the core dosing component of flocculant dosing station 6. When using the dosing pump, the output of the dosing pump can be adjusted according to the flow rate of the circulating washing liquid and the concentration of pollutants, so that the amount of flocculant dosing is adapted to the treatment requirements.

[0035] In one embodiment, the water supply pipe 51 is connected to the spray head 121 via a pipe 3, and a spray water supply valve 7 is provided on the pipe 3 between the water supply pipe 51 and the spray head 121.

[0036] This technical solution uses a water supply pipe 51 connected to a spray head 121 via a spray water supply valve 7. When the circulating washing liquid is insufficient, the circulating pump 2 malfunctions, or fresh water needs to be added to improve the washing effect, clean water or clean circulating washing liquid can be directly added to the spray head 121. This can replenish the water loss of the circulating system, dilute the concentration of pollutants in the circulating washing liquid by adding fresh water, or serve as a backup spray line to maintain the purification capacity of the circulating washing liquid.

[0037] In the specific implementation process, the spray water supply valve 7 can be an electromagnetic flow valve, which is linked with the liquid level gauge or pressure tester 12a in the washing tower. When the liquid level at the bottom of the washing tower is lower than the preset value, the water supply valve 7 can be opened automatically. Alternatively, when the concentration of pollutants in the circulating washing liquid exceeds the standard, the spray water supply valve 7 can be opened manually to perform water replacement. For example, when the concentration of suspended solids in the circulating washing liquid is detected to exceed 500 mg / L, the water supply valve can be opened to supply water for 30 minutes and then closed to dilute the concentration of suspended solids in the circulating washing liquid.

[0038] In one embodiment, the reverse spray pipe 12 includes a plurality of spray heads 121, wherein each spray head 121 is connected to the output end of the circulating pump 2 and the spray water supply valve 7 arranged in parallel through a pipe 3; or, some of the spray heads 121 are connected to the output end of the circulating pump 2 through a pipe 3, and other spray heads 121 are connected to the spray water supply valve 7 through a pipe 3.

[0039] This technical solution, through two connection methods of the spray head 121, can enable all spray heads 121 to simultaneously supply water to the circulating washing liquid and the water supply pipe 51 as needed, flexibly switching the washing water source. Alternatively, the spray heads 121 can be grouped and connected to the circulating pump 2 and the water supply valve respectively, realizing zoned operation of circulating washing liquid back spray and water supply spray, meeting the flue gas purification needs under different working conditions, or in the event of a failure in the circulating washing liquid back spray line, emergency operation can be carried out through water supply spray to maintain the purification capacity of the system.

[0040] In the specific implementation process, all spray heads 121 can be connected in a dual-path manner. During normal operation, the circulating washing liquid is supplied with water. If the concentration of suspended solids in the circulating washing liquid is high, the water supply pipe 51 is opened to supply water, or the water supply pipe 51 and the circulating washing liquid are supplied with water at the same time. Alternatively, the circulating washing liquid line valve can be opened during normal operation to supply water to some spray heads 121. If the operation of this part of the spray heads 121 is abnormal, the water supply valve is opened and the water supply pipe 51 supplies water to another part of the spray heads 121, thereby maintaining the purification capacity of the system under sudden conditions.

[0041] In one embodiment, the elevated water tank 5 is connected to an overflow pipe 8, the overflow pipe 8 is equipped with an overflow valve 81, and the overflow pipe 8 is connected to the overflow trough 122.

[0042] In this technical solution, the high-level water tank 5 is connected to the overflow tank 122 via the overflow pipe 8. When the water level in the high-level water tank 5 exceeds the preset height, the excess water can flow into the overflow tank 122 through the overflow pipe 8. The overflow valve 81 is normally open or opens at regular intervals to supply water from the high-level water tank 5 to the overflow tank 122, keeping the water path unobstructed and maintaining the water curtain effect of the overflow weir 1221 in emergency situations.

[0043] In the specific implementation process, the outlet of the overflow pipe 8 is set at the predetermined water level of the high-level water tank 5, and the interface of the overflow tank 122 connecting the overflow pipe 8 can be set on the opposite sides or multiple parts of the overflow weir 1221 to improve the uniformity of the water curtain.

[0044] In one embodiment, the overflow trough 122 is provided with a plurality of water inlets, which are evenly distributed along the circumference of the overflow trough 122, and the output end of the circulation pump 2 is connected to the plurality of water inlets arranged in parallel.

[0045] This technical solution uses a structure where the output end of the circulating pump 2 is connected to multiple inlets of the overflow tank 122. This allows the circulating washing liquid to enter the overflow tank 122 simultaneously from multiple directions, making the water flow distribution in the overflow tank 122 more uniform. This avoids uneven thickness of the overflow weir 1221 caused by water entering from one side, ensuring the integrity and uniformity of the reverse spray water curtain, improving the effect of reverse spray washing and the protection effect on the inner wall of the reverse spray pipe 12.

[0046] In the specific implementation process, there are no restrictions on the shape of the overflow channel 122 and the specific number of water inlets. For example, the number of water inlets can be 2, 4 or 6. The overflow channel 122 can be circular or rectangular. For example, a circular overflow channel 122 can be equipped with 3 water inlets at equal intervals. Each water inlet is equipped with an independent flow regulating valve. By adjusting the flow of each water inlet, the water level in the overflow channel 122 can be kept consistent, ensuring that the overflow weir 1221 forms a uniform and continuous water curtain.

[0047] In one embodiment, the bottom of the overflow trough 122 is provided with an overflow vent, the overflow vent is connected to a vent pipe 9, the vent pipe 9 is provided with a vent valve 91, and the vent pipe 9 is connected to the tower body 11.

[0048] This technical solution uses a structure where the bottom of the overflow tank 122 is connected to the tower body 11 via a drain valve 91. When the system is shut down for maintenance or when the circulating washing liquid in the overflow tank 122 needs to be replaced, the drain valve 91 can be opened to directly discharge the liquid in the overflow tank 122 back to the bottom of the washing tower. This avoids water accumulation in the overflow tank 122 and environmental pollution, and also allows the circulating washing liquid to be recycled back to the circulation system, reducing the waste of water resources and chemicals.

[0049] In the specific implementation process, the drain valve 91 can be a manual valve or an electric valve 11a. The diameter of the drain pipe 9 should match the volume of the overflow tank 122. When shutting down for maintenance, the drain valve 91 can be opened first to drain the liquid in the overflow tank 122, and then the overflow tank 122 can be cleaned.

[0050] Please refer to Figures 3 and 4. In one embodiment, the reverse nozzle 12 includes a settling hopper 123 located at the bottom end of the overflow trough 122. An overflow drain port 1231 is provided at the bottom end of the settling hopper 123. The overflow drain port 1231 is connected to an overflow drain pipe 1232. The height of the overflow drain port 1231 is lower than the height of the overflow drain port.

[0051] This technical solution uses a settling hopper 123 at the bottom of the overflow trough 122 to settle dust within the overflow trough 122. The dust is then collected at the overflow drain 1231 and transported to the ground via the overflow drain pipe 1232. This allows for the periodic removal of dust deposited at the bottom of the overflow trough 122, preventing dust accumulation from affecting the water intake and overflow efficiency of the overflow trough 122. This solution is adaptable to different factory installation spaces and scrubbing tower structures. The height of the overflow drain 1231 is lower than the height of the overflow vent to reduce the amount of dust discharged into the tower body 11 during venting.

[0052] In the specific implementation process, the overflow trough 122 is annular, and one or more set-in hoppers 123 and overflow drain pipes 1232 can be set to facilitate the discharge of dust deposits. Drainage can be carried out periodically, such as opening once a week to discharge the deposited dust, or using an ultrasonic sensor to test the dust height. When the height reaches the set value, drainage can be carried out.

[0053] In one embodiment, the reverse spray pipe 12 includes an inner pipe 124 and an outer pipe 125 that are nested together. The inner pipe 124 is connected to the tower body 11. The overflow groove 122 is defined between the outer pipe 125 and the inner pipe 124. The overflow discharge port 1231 is located at the bottom end of the outer pipe 125.

[0054] This technical solution uses an inner pipe 124 and an outer pipe 125 interlocking to form an overflow trough 122, making the structure of the backspray pipe 12 more compact. Simultaneously, the inner pipe 124 connects to the tower body 11, providing an upward channel for the flue gas. The overflow weir 1221 formed by the overflow trough 122 between the outer pipe 125 and the inner pipe 124 can directly perform backspray scrubbing on the rising flue gas. The structure of the outer pipe 125 increases the overall volume of the overflow trough 122, facilitating downward dust deposition, reducing the impact of dust on the top of the overflow weir 1221, and improving the water curtain formation effect. The overflow discharge port 1231 can be located on the bottom surface of the outer pipe 125 or on the side near the bottom surface of the outer pipe 125 to prevent dust accumulation at the bottom of the overflow trough 122.

[0055] In the specific implementation process, a sufficient gap should be maintained between the inner pipe 124 and the outer pipe 125, for example, the gap can be set to 10 cm or 30 cm. The depth of the overflow trough 122 should not be less than 50 cm as needed, for example, it can be 0.5 m, 2 m, 4 m or 8 m, to ensure sufficient space for dust settling, to accommodate washing water and form a stable water curtain. At the same time, since the volume of the overflow trough 122 increases the gravity and water pressure, the outer pipe 125 can be provided with sufficient installation stability by adding bottom supports and side supports to the reverse spray pipe 12. The inner pipe 124 and the outer pipe 125 can be made of corrosion-resistant materials, such as corrosion-resistant alloys or fiberglass, to adapt to the corrosive components in the flue gas and extend the service life of the equipment. The top of the outer pipe 125 can be designed as a slightly flared horn shape, which can better guide the washing water to overflow evenly, further ensuring the integrity and coverage area of ​​the water curtain, thereby improving the washing efficiency of the rising flue gas.

[0056] In one embodiment, a discharge pump 10 is provided at the bottom of the overflow drain pipe 1232.

[0057] By setting up a discharge pump 10 to increase the discharge pressure, it is easier to discharge the dust deposited in the overflow drain pipe 1232.

[0058] In practice, the type of discharge pump 10 is not limited; for example, it can be a screw pump or a gear pump. The discharge pump 10 can be installed on the ground or connected via a support, and the discharge end of the discharge pump 10 can be connected to the pipe 3 for discharge.

[0059] In one embodiment, a tower drain outlet is provided at the bottom of the tower body 11.

[0060] By setting a drain outlet at the bottom of the tower body 11, a large amount of dust and ineffective circulating washing liquid deposited at the bottom of the tower body 11 can be discharged periodically, preventing dust from accumulating at the bottom of the tower and affecting the normal suction of the circulating pump 2. At the same time, the ineffective circulating washing liquid can be discharged and replaced through the drain outlet, maintaining the purification capacity of the entire circulation system.

[0061] To address the problem of coke powder accumulating in the high-level water tank 5 and causing it to fail in the existing technology, this solution cuts off the acid backflow of the high-level water tank 5 in the traditional system, allowing the coke powder to be discharged through the inclined tube setter 4. A separate water supply pipe 51 is set up to replenish water to the high-level water tank 5, thereby ensuring the cleanliness of the high-level water tank 5 and its emergency water storage capacity. An emergency spray head 121 is installed on the inner wall of the reverse spray pipe 12 above the power wave scrubbing tower 1. The spray head 121 is connected to the emergency spray pipe 3 and the emergency spray water supply electric valve 11a, and the process water in the plant area is connected to the water supply pipe 51 as the water source. When the main spray system fails or the water pressure drops, the pressure tester 12a on the pipe 3 at the output end of the circulating pump and the washing liquid spray branch pipe can detect the pressure change. When the pressure drops to the set value, the emergency spray water supply electric valve 11a is opened by the control system, and the emergency spray head 121 can be started immediately to spray for cooling and desulfurization and dust removal, avoiding dry burning in the power wave scrubbing tower 1 and causing equipment damage, and protecting the key equipment from high temperature damage.

[0062] A water supply pipe 51 and a booster pump are connected to the high-level water tank 5. The water supply pipe 51 connects the process water circuit of the plant to the water supply port at the top of the high-level water tank 5 and connects to the overflow pipe 8 of the high-level water tank 5. Then it is connected to the pipe 3 at the bottom output end of the high-level water tank 5. Normally, the high-level water tank 5 is filled with process water. In case of emergency, the booster pump can be started to directly supply water to the overflow weir 1221 of the power wave scrubbing tower 1.

[0063] The overflow weir 1221 of the power wave scrubbing tower 1 is fed by three branch pipes after the water converges from the pipe 3 at the bottom output end of the high-level water tank 5 and the pipe 3 at the output end of the circulating pump 2. The three branch pipes are at an angle of 120 degrees and are located on the same horizontal plane. Each branch pipe is equipped with a flow valve. The flow rate of the three water supply lines is controlled and adjusted by the flow valves so that the water in the overflow weir 1221 can flow evenly to the inner wall of the downward reverse spray pipe 12, ensuring uniform cooling of the pipe 3.

[0064] In this scheme, all circulating washing liquid (including high-concentration coke powder) no longer passes through the high-level water tank 5, but instead undergoes solid-liquid separation through the inclined tube settling device 4. At the same time, a water supply pipe 51 is connected to replenish water to the high-level water tank 5. This water supply pipe 51 can also directly supply water to the overflow tank 122 or spray head 121 of the reverse spray pipe 12 via the pipe 3 at the bottom output end.

[0065] After the circulating washing liquid settles in the inclined tube settling tank 4, suspended solids such as coke powder in the acid solution are separated. The supernatant of the acid solution is returned to the dynamic wave scrubbing tower 1 through the pipe 3 at the output end of the inclined tube settling tank 4. The flocculant is an organic flocculant (PAM) added to the pipe 3 at the outlet of the dynamic wave scrubbing tower 1 to the inlet end of the circulating pump 2, which causes suspended solids, colloidal particles and dissolved pollutants in the water to aggregate into large flocs. This, in conjunction with the inclined plate settling tank 4, significantly improves water quality, prevents equipment scaling and clogging, and enhances desulfurization efficiency. At the same time, part of the flue gas in the inclined tube settling tank 4 enters the primary packed tower for further treatment, and another part of the waste gas enters the small desorption tower for treatment. The bottom of the inclined tube settling tank 4 is equipped with a drain port, which can discharge sludge to the concentrated phase tank for treatment.

[0066] Under normal circumstances, the high-level water tank 5 is filled with water through the water supply pipe 51 for emergency backup. In case of emergencies (such as failure of the acid circulation pump 2), the high-level water tank 5 and the booster pump on the high-level water tank 5 can be activated simultaneously to directly replenish the water tank of the power wave scrubbing tower 1 through the pipe 3 at the bottom output end. At the same time, an overflow drain valve 91 and an overflow drain pipe 9 are installed below the overflow weir 1221. When the water flow into the overflow weir 1221 is too large or when dredging and sewage discharge are required, the water can be discharged into the power wave scrubbing tower 1 below through the drain pipe 9. Two sewage discharge ports 11 are installed at the bottom of the power wave scrubbing tower 1 to discharge the dilute acid solution at the bottom of the power wave scrubbing tower 1 to the dilute acid underground storage tank.

[0067] Emergency spray heads 121 are installed on the inner wall of the reverse nozzle 12 above the power wave scrubbing tower 1. These emergency spray heads are evenly distributed throughout the power wave scrubbing tower 1 to ensure uniform atomization coverage and maintain desulfurization efficiency even in emergency situations. The emergency spray system ensures basic desulfurization function is maintained during main system failures, preventing excessive emissions of pollutants such as SO2 and meeting environmental protection requirements. The emergency system ensures uninterrupted production during main system failures, avoiding production losses and additional costs due to downtime.

[0068] The above description is merely an exemplary embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural transformations made using the contents of the present invention specification and drawings under the technical concept of the present invention, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. A flue gas purification system, characterized in that... include: A dynamic wave scrubbing tower includes a tower body and a backspray pipe connected to the tower body. The backspray pipe includes a spray head and an overflow trough, with the overflow trough located at the top of the backspray pipe and its inner wall configured as an overflow weir. A circulating pump has its input end connected to the bottom of the tower body via a pipe, and its output end connected to the overflow trough and the spray head via a pipe. A settling device is connected between the output end of the circulating pump and the bottom of the tower body via a pipe, and the settling device is equipped with a settling discharge port. An elevated water tank is also included, with a water supply pipe connected to the elevated water tank. The bottom of the elevated water tank is connected to the overflow trough via a pipe, and an emergency valve is installed between the bottom of the elevated water tank and the overflow trough.

2. The flue gas purification system as described in claim 1, characterized in that, The flue gas purification system also includes a flocculant dosing station, which is located on the pipeline between the input end of the circulating pump and the bottom of the tower.

3. The flue gas purification system as described in claim 1, characterized in that, The water supply pipe is connected to the spray head via a pipe, and a spray water supply valve is installed on the pipe between the water supply pipe and the spray head.

4. The flue gas purification system as described in claim 3, characterized in that, The reverse spray pipe includes a plurality of spray heads, wherein each spray head is connected to the output end of the circulating pump and the spray water supply valve arranged in parallel through a pipe; or, some of the spray heads are connected to the output end of the circulating pump through pipes, and other spray heads are connected to the spray water supply valve through pipes.

5. The flue gas purification system as described in claim 1, characterized in that, The elevated water tank is connected to an overflow pipe, and an overflow valve is installed on the overflow pipe. The overflow pipe is connected to the overflow tank.

6. The flue gas purification system as described in claim 1, characterized in that, The overflow trough is provided with multiple water inlets, which are evenly distributed along the circumference of the overflow trough. The output end of the circulation pump is connected to the multiple water inlets arranged in parallel.

7. The flue gas purification system as described in claim 1, characterized in that, The bottom of the overflow trough is provided with an overflow vent, the overflow vent is connected to a vent pipe, the vent pipe is provided with a vent valve, and the vent pipe is connected to the tower body.

8. The flue gas purification system as described in claim 7, characterized in that, The reverse spray pipe includes a settling hopper located at the bottom of the overflow trough. An overflow drain outlet is provided at the bottom of the settling hopper. An overflow drain pipe is connected to the overflow drain outlet, and the height of the overflow drain outlet is lower than the height of the overflow vent.

9. The flue gas purification system as described in claim 8, characterized in that, The reverse spray pipe includes an inner pipe and an outer pipe that are nested together. The inner pipe is connected to the tower body, and the overflow trough is defined between the outer pipe and the inner pipe. The overflow outlet is located at the bottom end of the outer pipe.

10. The flue gas purification system as described in claim 7, characterized in that, A discharge pump is installed at the bottom of the overflow drain pipe.

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