A cooling, dust-removing and fog-removing tower

Abstract

The present invention provides a cooling, dust-removing and demisting tower, comprising a vertically arranged cylinder, a flue gas inlet provided on the lower sidewall of the cylinder, a dust-removing and demisting device and a spray device spaced apart vertically within the upper portion of the cylinder, a flue gas outlet provided on the top surface of the cylinder, and a sewage discharge mechanism provided at the bottom of the cylinder. The dust-removing and demisting device comprises an acceleration section, a cyclone, and a float demister, which are sequentially connected from bottom to top. An annular flow channel connected to the cyclone is formed within the acceleration section, and the flow cross-section of the annular flow channel gradually decreases from bottom to top. The cooling, dust-removing and demisting tower of the present invention can cool and remove dust and mist from flue gas, and can effectively remove dust droplets from the flue gas.

Description

Technical Field

[0001] The present invention relates to the field of flue gas treatment, and in particular to a cooling, dust removal and mist removal tower. Background Art

[0002] Steel slag is a byproduct produced during the steelmaking process. To meet subsequent slag processing requirements, the high-temperature slag must be cooled. Currently, the hot simmering slag process is widely used in China. This generates dust during the slag tank entry and water pumping stages. This dust contains large amounts of CaO, MgO, and water vapor, with a dust concentration of approximately 5g / Nm³. Traditional electrostatic precipitators (ESPs) and bag filters are not suitable for direct use. These dust particles are directly discharged into the workshop, creating a harsh working environment. Recent environmental regulations have become increasingly stringent, imposing new requirements on the dust content of flue gas emitted from slag processing, generally limiting particulate matter emissions to between 20 and 100mg / Nm³.

[0003] A system and method for dust removal of flue gas from a hot slag pool is currently available (Chinese invention patent publication number CN112121567A, published on December 25, 2020). The system includes a spray tower, a pneumatic high-efficiency dust and mist remover, and a hydrocyclone. The process is as follows: flue gas first enters the spray tower, where it is cleaned by two water wash sections. It then enters the upper pneumatic high-efficiency mist remover, where it is dusted and misted before being discharged from the top. However, in this system, the flue gas enters the tower from the side wall of the spray tower, so the flue gas entering the spray tower cannot be guaranteed to be evenly distributed, thereby reducing the subsequent spraying and dust removal effects; the two layers of water washing sections are exactly the same, and only play the role of spraying and washing the flue gas. The fine dust contained in the flue gas is not easy to agglomerate and grow, and no favorable smoke and dust conditions are created for the subsequent dust removal and demisting devices; the pneumatic demister adopts a single form of cyclone plate, and only relies on the centrifugal force difference generated by the rotation of gas and liquid to capture dust droplets, and the capture efficiency of fine dust particles is relatively low.

[0004] There is also a dust removal and dehumidification device for slag treatment waste gas treatment in the prior art (a Chinese utility model patent with the authorization announcement number CN211216015U and the authorization announcement date of August 11, 2020), which includes a cyclone dust collector, a connecting pipe, a filter tower and a nozzle, etc. The implementation process is as follows: the flue gas enters the cyclone dust collector for coarse dust removal and dehydration, and then enters the filter tower through the connecting pipe. The filter tower adopts a multi-cylinder structure, one is in a cleaning state, and the rest are in a processing and filtering state. The flue gas after filtration is discharged out of the tower. However, the flue gas first passes through a cyclone dust collector for coarse dust removal. As we all know, the cyclone dust collector only has an obvious capture effect on large particles, and the dehydration effect is also poor. The subsequent fine dust removal facilities are heavily loaded; using a multi-cylinder parallel filter tower to perform fine dust removal and demisting on the flue gas not only occupies a large area, but also the resistance loss of the filter tower alone reaches 1000Pa, and the resistance of the entire dust removal and dehumidification system is relatively high.

[0005] Therefore, the inventors, relying on their many years of experience and practice in related industries, have proposed a cooling, dust removal and mist removal tower to overcome the defects of the prior art. Summary of the Invention

[0006] The object of the present invention is to provide a cooling, dust-removing and mist-removing tower, which can cool the flue gas and remove dust and mist, and can effectively remove dust droplets in the flue gas.

[0007] The object of the present invention is achieved in this way. A cooling, dust-removing and mist-removing tower comprises a vertically arranged cylinder; a flue gas inlet is provided on the lower side wall of the cylinder, a dust-removing and mist-removing device and a spraying device are provided in the upper part of the cylinder at intervals, a flue gas outlet is provided on the top surface of the cylinder, and a sewage discharge mechanism is provided at the bottom of the cylinder; the dust-removing and mist-removing device comprises an acceleration section, a cyclone and a float demister connected in sequence from bottom to top, an annular flow channel connected to the cyclone is formed in the acceleration section, and the flow cross-section of the annular flow channel gradually decreases from bottom to top.

[0008] In a preferred embodiment of the present invention, the acceleration section includes a reducing pipe and a head that is intermittently arranged in the reducing pipe and has a closed bottom. The inner diameter of the reducing pipe gradually decreases from bottom to top, and the bottom end of the reducing pipe is connected to the cylinder; the outer diameter of the head gradually expands from bottom to top, and the interval between the reducing pipe and the head constitutes an annular flow channel.

[0009] In a preferred embodiment of the present invention, the cyclone includes a first inner tube and a first outer tube arranged coaxially, and a plurality of swirl blades are circumferentially spaced between the first inner tube and the first outer tube; the bottom end of the first inner tube is connected to the top end of the head, and the bottom end of the first outer tube is connected to the top end of the reducing tube.

[0010] In a preferred embodiment of the present invention, the float demister includes a coaxially arranged second inner tube and a second outer tube, an annular bottom wire mesh is connected to the bottom ends of the second inner tube and the second outer tube, and the annular bottom wire mesh is connected to the top ends of the first inner tube and the first outer tube; an annular top wire mesh is detachably connected to the top ends of the second inner tube and the second outer tube, and a plurality of floats are provided in an annular cavity surrounded by the second inner tube, the second outer tube, the annular bottom wire mesh and the annular top wire mesh.

[0011] In a preferred embodiment of the present invention, a spherical sealing plate is provided at the top end of the second inner tube, and the spherical surface of the spherical sealing plate is protruding upward.

[0012] In a preferred embodiment of the present invention, the dust removal and demisting device also includes an expansion pipe arranged above the float demister and the diameter of which gradually expands upward. A lower cleaner is provided in the expansion pipe, and the lower cleaner has a plurality of lower nozzles with the nozzles facing downward; the top and bottom ends of the expansion pipe are respectively connected to the cylinder and the second outer tube.

[0013] In a preferred embodiment of the present invention, the spray device includes an upper spray device and a lower spray device spaced apart from each other, the lower spray device includes a plurality of cooling nozzles with nozzles facing downward, the upper spray device includes a plurality of atomizing nozzles with nozzles facing downward, and the spray hole diameter of the cooling nozzle is larger than the spray hole diameter of the atomizing nozzle.

[0014] In a preferred embodiment of the present invention, the smoke inlet is composed of an inlet pipe inserted into the side wall of the cylinder, and the inner end of the inlet pipe extends into the center of the cylinder, and the inlet pipe is arranged obliquely downward from the side wall of the cylinder toward the inner cavity of the cylinder.

[0015] In a preferred embodiment of the present invention, a deflector water baffle is further provided in the cylinder and between the dust and mist removal device and the smoke outlet.

[0016] In a preferred embodiment of the present invention, an upper washer is provided in the cylinder and between the dust removal and mist removal device and the deflection water retainer. The upper washer has a plurality of upper nozzles with the nozzles facing upward.

[0017] In a preferred embodiment of the present invention, the top of the cylinder is an outlet pipe with a diameter that gradually decreases upward, and the top end of the outlet pipe constitutes a smoke outlet.

[0018] In a preferred embodiment of the present invention, the sewage discharge mechanism includes a conical tube whose diameter gradually decreases from top to bottom. The conical tube is located below the flue gas inlet, and the top end of the conical tube is connected to the inner wall of the cylinder. The bottom end of the conical tube is connected to the first end of a sewage discharge pipe, and the second end of the sewage discharge pipe passes through the side wall of the cylinder and extends to the outside of the cylinder.

[0019] As described above, the cooling, dust removal and demisting tower of the present invention can cool the flue gas and remove dust and mist through the cooperation of the spray device, the acceleration section, the cyclone and the floating ball demister; the airflow can be evenly guided to the cyclone through the acceleration section and the flue gas can be gradually accelerated; the swirling effect of the cyclone and the floating ball dust removal and demisting technology of the floating ball demister can remove dust droplets in the flue gas to the maximum extent, effectively remove most of the dust contained in the flue gas, and the dust concentration of the outlet flue gas can be reduced to 20mg / Nm 3 The dust concentration in the flue gas meets emission requirements. Furthermore, the water mist content in the outlet flue gas is low, minimizing the "white smoke" phenomenon. The entire equipment is simple and reliable, with low resistance and a small footprint. It is particularly key to achieving ultra-low emissions from hot slag flue gas. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The following drawings are intended only to illustrate and explain the present invention, and are not intended to limit the scope of the present invention.

[0021] Figure 1 : A schematic structural diagram of a cooling, dust removal and mist removal tower provided by the present invention.

[0022] Figure 2 : A schematic structural diagram of the dust removal and mist removal device provided by the present invention.

[0023] Figure 3 : A three-dimensional diagram of the cyclone provided by the present invention.

[0024] Figure 4 : A top view of the cyclone provided by the present invention.

[0025] Figure 5 : A schematic structural diagram of the float demister provided by the present invention.

[0026] Figure 6 : A schematic structural diagram of the annular bottom screen provided by the present invention.

[0027] Figure 7 : A schematic structural diagram of the annular top screen provided by the present invention.

[0028] Description of Figure Numbers:

[0029] 100, cylinder;

[0030] 1. Sewage discharge mechanism; 11. Conical pipe; 12. Sewage discharge pipe;

[0031] 2. Inlet pipe; 21. Flue gas inlet;

[0032] 3. Spraying device; 31. Lower spraying device; 32. Upper spraying device;

[0033] 4. Dust and mist removal device;

[0034] 41. Acceleration section; 411. Annular flow channel; 412. Reduced diameter pipe; 413. End cap;

[0035] 42. cyclone; 421. first inner tube; 422. first outer tube; 423. swirl blade;

[0036] 43. Floating ball demister; 431. Second inner tube; 432. Second outer tube; 433. Annular bottom screen; 434. Annular top screen; 4341. Reinforcement rib; 435. Annular cavity; 436. Floating ball; 437. Spherical sealing plate;

[0037] 44. Expanded diameter pipe;

[0038] 45. Lower washer;

[0039] 5. Install the washer;

[0040] 6. Baffle water retainer;

[0041] 7. Outlet pipe; 71. Smoke outlet;

[0042] 200. Base. DETAILED DESCRIPTION

[0043] In order to have a clearer understanding of the technical features, purposes and effects of the present invention, specific embodiments of the present invention are now described with reference to the accompanying drawings.

[0044] like Figures 1 to 7 As shown, this embodiment provides a cooling, dust removal, and mist removal tower, comprising a vertically arranged cylinder 100. A flue gas inlet 21 is provided on the lower sidewall of the cylinder 100. A dust removal and mist removal device 4 and a spray device 3 are provided in the upper portion of the cylinder 100, spaced apart from each other. A flue gas outlet 71 is provided on the top surface of the cylinder 100, and a sewage discharge mechanism 1 is provided at the bottom of the cylinder 100. The dust removal and mist removal device 4 comprises an acceleration section 41, a cyclone 42, and a float demister 43, which are sequentially connected from bottom to top. An annular flow channel 411 is formed in the acceleration section 41 and is connected to the cyclone 42. The flow cross-section of the annular flow channel 411 gradually decreases from bottom to top.

[0045] The entire cooling, dust removal and mist removal tower is a vertical structure, and the cylinder 100 is generally cylindrical and serves as a channel for the flow of flue gas. Figure 1 The upper and lower positions shown in the figure are actually the spraying device 3 and the dust removal and demisting device 4 arranged in sequence along the direction of the flue gas flow. During use, the flue gas collected by the front-end process capture hood enters the tower through the flue gas inlet 21 and is cooled by the spray device 3. When the dust droplets formed enter the acceleration section 41, the upward-converging annular flow channel 411 causes the flue gas to be gradually accelerated and evenly enter the cyclone 42. The flue gas reaches its maximum speed in the cyclone 42, thereby generating sufficient centrifugal force. Under the swirling action of the cyclone 42, the dust droplets are separated from the flue gas, achieving the effect of dust removal and demisting. After leaving the cyclone 42, the flue gas enters the float demister 43. As the flue gas passes through, the float 436 in the float demister 43 is lifted and rotated by the airflow. The dust droplets elastically collide with the spheres, adhere to them, and condense, causing them to be captured on the surface of the float 436, further removing dust and mist. Finally, the flue gas is discharged from the tower through the flue gas outlet 71, and the spray water and the dust-containing water removed by the dust removal and demisting device 4 are regularly discharged by the sewage discharge mechanism 1.

[0046] Therefore, the cooling, dust removal and demisting tower in this embodiment can cool the flue gas and remove dust and mist through the cooperation of the spray device 3, the acceleration section 41, the cyclone 42 and the floating ball demister 43; the acceleration section 41 can evenly guide the airflow to the cyclone 42 and gradually accelerate the flue gas. The swirling effect of the cyclone 42 and the floating ball dust removal and demisting technology of the floating ball demister 43 can remove dust droplets in the flue gas to the maximum extent, effectively remove most of the dust contained in the flue gas, and reduce the dust concentration of the outlet flue gas to 20 mg / Nm 3The dust concentration in the flue gas meets emission requirements. Furthermore, the water mist content in the outlet flue gas is low, minimizing the "white smoke" phenomenon. The entire equipment is simple and reliable, with low resistance and a small footprint. It is particularly key to achieving ultra-low emissions from hot slag flue gas.

[0047] In a specific implementation, such as Figure 1 and Figure 2 As shown, the acceleration section 41 includes a reducing tube 412 and a bottom-sealed end cap 413 interspersed within the reducing tube 412. The inner diameter of the reducing tube 412 gradually decreases from bottom to top, and the bottom end of the reducing tube 412 is connected to the cylinder 100. The outer diameter of the end cap 413 gradually increases from bottom to top, and the gap between the reducing tube 412 and the end cap 413 forms an annular flow channel 411.

[0048] Generally, the end cap 413 is a hollow structure. The end cap 413 and the reducing pipe 412 are designed at a specific angle (the specific angle is determined according to needs), thereby forming an annular flow channel 411 with a flow cross section that gradually shrinks upward, so that the smoke is gradually accelerated.

[0049] Reference Figures 2 to 4 The cyclone 42 includes a coaxially arranged first inner tube 421 and a first outer tube 422. A plurality of swirl blades 423 are circumferentially spaced between the first inner tube 421 and the first outer tube 422. The bottom end of the first inner tube 421 is connected to the top end of the head 413, and the bottom end of the first outer tube 422 is connected to the top end of the reducing tube 412.

[0050] Each swirl blade 423 is welded to the outer wall of the first inner tube 421 and is evenly arranged at a predetermined angle. In this embodiment, each swirl blade 423 preferably has an angle of 55° with the horizontal plane to achieve better separation of dust droplets from the flue gas. Assuming the number of swirl blades 423 is N, the flue gas entering the cyclone 42 is evenly divided into N channels. The flue gas velocity within each channel is within a reasonable range. If the velocity is too low, the centrifugal force generated is insufficient, preventing the droplets from separating from the flue gas. If the velocity is too high, the droplets will collide with the tube wall after separation, gaining reverse velocity and re-entering the flue gas. In this embodiment, the flue gas velocity in the cyclone 42 is preferably controlled between 6 and 10 m / s (this flue gas velocity is determined by the flow cross-section of the annular flow channel 411, and the flow cross-section size can be determined based on different flue gas volumes) to achieve optimal dust and mist removal.

[0051] Reference Figure 2 as well as Figures 5 to 7The float demister 43 includes a coaxially arranged second inner tube 431 and second outer tube 432. An annular bottom screen 433 is connected to the bottom ends of the second inner tube 431 and the second outer tube 432, and the annular bottom screen 433 is connected to the top ends of the first inner tube 421 and the first outer tube 422. An annular top screen 434 is detachably connected to the top ends of the second inner tube 431 and the second outer tube 432. A plurality of floats 436 are disposed within an annular cavity 435 formed by the second inner tube 431, the second outer tube 432, the annular bottom screen 433, and the annular top screen 434.

[0052] The entire float demister 43 is an annular container filled with an appropriate number of floats 436 to further capture droplets in the flue gas. The floats 436 are preferably lightweight plastic balls, and their specific size is determined according to needs. Generally, the volume of the floats 436 in the annular cavity 435 is required to account for approximately one-quarter of the annular cavity 435. After passing through the mesh gaps of the annular bottom screen 433, the flue gas elastically collides with, adheres to, and condenses with the floating floats 436 in the annular cavity 435, causing it to be captured on the surface of the floats 436, thereby achieving the purpose of dust and mist removal. After dust and mist removal, the flue gas passes through the mesh gaps of the annular top screen 434 and moves upward. The annular top screen 434 is preferably connected to the top of the second inner tube 431 and the second outer tube 432 using a flange, which can be disassembled to facilitate replacement of the floats 436. Of course, the annular top screen 434 can also be connected using other connection methods as long as it is easy to disassemble. Generally, a plurality of radial reinforcing ribs 4341 are provided at intervals along the circumference of the annular top screen 434 to ensure structural strength.

[0053] Preferably, a spherical sealing plate 437 is provided at the top end of the second inner tube 431, with the spherical surface of the spherical sealing plate 437 protruding upward. The upper surface of the spherical sealing plate 437 is formed into a shape with a high center and low surroundings to prevent liquid from entering the middle portion of the dust and mist removal device 4 (i.e., the space enclosed by the sealing head 413, the first inner tube 421, and the second inner tube 431), thereby ensuring smoother water flow and sufficient drainage without water accumulation.

[0054] In order to facilitate the regular cleaning of the dust-accumulating components in the dust removal and demisting device 4 (such as the annular top screen 434, the annular bottom screen 433, the float 436 and the cyclone 42, etc.), Figure 1 and Figure 2As shown, the dust removal and demisting device 4 also includes an expanding tube 44, which is positioned above the float demister 43 and gradually expands in diameter upward. A lower washer 45 is located within the expanding tube 44 and comprises multiple downwardly-oriented lower nozzles. The top and bottom ends of the expanding tube 44 are respectively connected to the barrel 100 and the second outer tube 432 to prevent the components within the dust removal and demisting device 4 from becoming clogged by accumulated dust. It will be appreciated that the expanding tube 44 is primarily designed to facilitate the connection between the float demister 43 and the barrel 100. Generally, the diameter of the second outer tube 432 also gradually expands from bottom to top, making it easier to transition to the expanding tube 44.

[0055] More preferably, Figure 1 As shown, the spray device 3 includes an upper spray device 32 and a lower spray device 31 spaced apart from each other. The lower spray device 31 includes a plurality of cooling nozzles with nozzles facing downward, and the upper spray device 32 includes a plurality of atomizing nozzles with nozzles facing downward, and the nozzle hole diameter of the cooling nozzle is larger than the nozzle hole diameter of the atomizing nozzle.

[0056] The cooling nozzle has a relatively large spray hole diameter, and the water inlet pipe connected to it during use also has a large diameter, and the water inlet volume is also large (generally, the diameter of the connected water inlet pipe is 65-80 mm, and the water inlet volume is 10-15 t / h), thereby forming a large-flow nozzle. The lower-layer spray device 31 sprays the flue gas through multiple large-flow cooling nozzles, which can quickly cool the flue gas while cleaning the large particles of dust contained in the flue gas. The number of cooling nozzles is determined by the diameter of the cylinder, ensuring that the spray cross-section (that is, the horizontal cross-section formed by the water sprayed by each cooling nozzle) is not less than the cross-section formed by the inner diameter of the cylinder 100, so that the flue gas can fully contact the spray water. The lower-layer spray device 31 can be provided with one or more layers according to the requirements of the inlet flue gas temperature and outlet temperature.

[0057] The spray hole of the atomizing nozzle is relatively small, and the diameter of the water inlet pipe connected to it during use is also relatively small, so the water intake is also relatively small. The lower spray device 31 can produce a large amount of atomized water through the arrangement of multiple atomizing nozzles. On the one hand, it continues to cool the flue gas to ensure that the flue gas reaches a saturated state (generally required not to exceed 70°C). At the same time, the droplets produced by the atomizing nozzle agglomerate with the fine particles of dust in the flue gas, and the diameter of the dust-containing droplets gradually increases, creating favorable conditions for subsequent dust removal and demisting. The upper spray device 32 is generally arranged as a layer.

[0058] The spray device 3 in this embodiment utilizes a combination of two nozzles with different nozzle apertures and flow rates: a lower spray device 31 with a large-flow nozzle and an upper spray device 32 with an atomizing nozzle. This combination not only rapidly cools the flue gas, particularly when treating high-temperature and high-volume flue gas, but also atomizes and aggregates fine dust particles in the flue gas, further facilitating subsequent dust and mist removal. The structures of each nozzle are conventional and will not be further described here.

[0059] Further, if Figure 1 As shown, the flue gas inlet 21 is formed by an inlet pipe 2 inserted into the side wall of the cylinder 100, with the inner end of the inlet pipe 2 extending into the center of the cylinder 100. This allows the flue gas to enter through the inlet pipe 2 and diffuse outward from the center of the cylinder 100, ensuring uniform distribution of the flue gas and helping to ensure the subsequent spraying, dust removal, and demisting effects. The inlet pipe 2 is preferably a circular tube to ensure uniform airflow distribution within the inlet pipe 2.

[0060] Preferably, the inlet pipe 2 is arranged downwardly from the side wall of the cylinder 100 toward the inner cavity of the cylinder 100. The specific angle of inclination is determined according to needs. The downward inclination of the inlet pipe 2 after extending into the cylinder 100 can ensure that water in the tower flowing down from the upper part does not enter the inlet pipe 2, thereby preventing the water in the tower from flowing into the inlet pipe 2 and affecting the front-end process. In addition, the inclined setting of the inlet pipe 2 can ensure that if there is any mechanical water in the inlet flue gas, the water contained therein can flow smoothly into the bottom of the tower.

[0061] Further, if Figure 1 As shown, a deflector 6 is also provided within the cylinder 100, between the dust and mist removal device 4 and the flue gas outlet 71. This deflector 6 comprises a plurality of horizontally spaced deflectors, and its specific structure is conventional. Liquid droplets may still remain in the flue gas after passing through the dust and mist removal device 4. When the flue gas passes through the deflectors within the deflector 6, the airflow direction is changed. The inertia difference between the gas and liquid allows the deflectors to capture the droplets, further enhancing the dust and mist removal effect.

[0062] In order to facilitate the regular flushing of the dust accumulated on the baffles in the baffle water retainer 6, as shown in FIG. Figure 1 As shown, an upper washer 5 is provided in the cylinder 100 and between the dust removal and mist removal device 4 and the deflection water retainer 6. The upper washer 5 has a plurality of upper nozzles with the nozzles facing upward.

[0063] In order to facilitate the connection of the smoke outlet 71 with the subsequent pipeline, the top of the cylinder 100 is an outlet pipe 7 with a diameter that gradually decreases upward, and the top end of the outlet pipe 7 constitutes the smoke outlet 71.

[0064] Reference Figure 1The sewage discharge mechanism 1 includes a tapered tube 11, the diameter of which gradually decreases from top to bottom. This tube 11 is located below the flue gas inlet 21, with its top end connected to the inner wall of the cylinder 100. The bottom end of this tube 11 is connected to the first end of a sewage discharge pipe 12, the second end of which passes through the side wall of the cylinder 100 and extends outside of the cylinder 100. This tube 11 is used to collect spray water and dust-laden water removed by the dust removal and demisting device 4. The sewage discharge pipe 12 is used to regularly discharge the sewage collected in the tube 11 into the tower.

[0065] In addition, a base 200 (also in a ring shape) is provided at the bottom of the cylinder 100 for supporting the entire device.

[0066] The working principle of the entire cooling, dust removal and mist removal tower is as follows:

[0067] The flue gas to be treated enters the cylinder 100 through the inlet pipe 2; the flue gas is first cooled and washed by the water sprayed from the lower spray device 31; the flue gas rises to the upper spray device 32 and is sprayed and cooled for the second time by the atomized water. At this time, the flue gas temperature reaches saturation and contains a large number of droplets; the flue gas enters the dust removal and demisting device 4, is first gradually accelerated by the acceleration section 41, and after passing through the cyclone 42 and the float demister 43, the dust-containing droplets in the flue gas are captured, thereby achieving the purpose of dust removal and demisting; the purified flue gas continues to rise and passes through the deflection water retainer 6, and the droplets in the flue gas are further captured by the deflection blades in the deflection water retainer 6; the clean flue gas after cooling, dust removal and demisting is finally discharged from the tower through the outlet pipe 7; the separated sewage flows downward along the inner wall of the cylinder 100 into the tapered pipe 11 and is discharged from the tower through the sewage pipe 12.

[0068] In order to ensure that the dust accumulated in the dust removal and demisting device 4 and the deflecting water deflector 6 is cleaned in time and does not get clogged, the dust removal and demisting device 4 and the deflecting water deflector 6 can be cleaned periodically by setting the lower cleaning device 45 and the upper cleaning device 5; the cleaning order is first up and then down: first open the upper cleaning device 5 and flush the deflecting water deflector 6, and the flushing time is generally 5 minutes (the time can be adjusted according to the dust accumulation situation); after the deflecting water deflector 6 is flushed, close the upper cleaning device 5, open the lower cleaning device 45, and flush the dust removal and demisting device 4, and the flushing time is generally 8 to 10 minutes (the time can be adjusted according to the dust accumulation situation), and close the lower cleaning device 45 after flushing, thus completing a complete flushing cycle.

[0069] The entire cooling, dust removal and demisting tower treats flue gas (such as hot stewed slag flue gas) through various methods such as spraying, cyclone removal, float, and deflection; the spray device 3 is divided into a large-flow nozzle on the lower layer and an atomizing nozzle on the upper layer, which cools and washes the flue gas while enhancing the agglomeration of fine dust in the flue gas; a head 413 is provided at the inlet center of the dust removal and demisting device 4, which can evenly guide the flue gas into the cyclone 42; and by coupling the cyclone and float dust removal and demisting technology, the dust droplets in the flue gas are removed to the maximum extent; the entire cooling, dust removal and demisting tower is highly coupled with cooling, dust removal and demisting functions, realizing the coordinated and comprehensive treatment of the flue gas, which can reduce the flue gas temperature to no more than 70°C and the dust concentration to below 20mg / Nm3. The dust concentration of the flue gas meets the emission requirements, and due to the low water mist content in the flue gas, the "white smoke" phenomenon can be minimized. Furthermore, the airflow within the tower primarily bends upon entering inlet pipe 2. As the flue gas exits the inlet pipe 2 and diffuses upward, the airflow remains smooth within the tower. Furthermore, the flue gas velocity is highest within the dust and mist removal device 4 and is lower elsewhere. Consequently, the resistance loss across the entire tower is relatively low, not exceeding 800 Pa.

[0070] The above is only an illustrative embodiment of the present invention and is not intended to limit the scope of the present invention. Any equivalent changes and modifications made by those skilled in the art without departing from the concept and principle of the present invention should fall within the scope of protection of the present invention.

Claims

1. A cooling, dust removal and mist removal tower, characterized in that: It includes a vertically arranged cylinder; A flue gas inlet is provided on the lower side wall of the cylinder, a dust removal and demisting device and a spray device are provided in the upper part of the cylinder at intervals, a flue gas outlet is provided on the top surface of the cylinder, and a sewage discharge mechanism is provided at the bottom of the cylinder; the dust removal and demisting device comprises an acceleration section, a cyclone and a float demister which are sequentially connected from bottom to top, an annular flow channel connected to the cyclone is formed in the acceleration section, and the flow cross-section of the annular flow channel gradually decreases from bottom to top; the acceleration section comprises a reducing pipe and a head which is spaced apart and passed through the reducing pipe and has a closed bottom, the inner diameter of the reducing pipe gradually decreases from bottom to top, and the bottom end of the reducing pipe is connected to the cylinder; the outer diameter of the head gradually increases from bottom to top, and the interval between the reducing pipe and the head constitutes the annular flow channel; The spray device includes an upper spray device and a lower spray device spaced apart from each other. The lower spray device includes a plurality of cooling nozzles with nozzles facing downward, and the upper spray device includes a plurality of atomizing nozzles with nozzles facing downward. The diameter of the water inlet pipe connected to the cooling nozzle is 65 to 80 mm, and the water inlet volume is 10 to 15 t / h, so as to form a large-flow nozzle. The number of the cooling nozzles can make the spray cross-section not less than the cross-section formed by the inner diameter of the cylinder. When the cooling nozzle sprays the flue gas, it can quickly cool it down and clean the large particles of dust contained in the flue gas. The cooling nozzle The spray hole aperture is larger than the spray hole aperture of the atomizing nozzle, the water inlet pipe diameter connected to the atomizing nozzle is smaller than the water inlet pipe diameter connected to the cooling nozzle, and the atomizing nozzle can continue to cool the flue gas so that the flue gas reaches a saturated state and the temperature does not exceed 70°C. At the same time, the droplets generated by the atomizing nozzle can agglomerate with the fine particles of dust in the flue gas, so that the diameter of the dust-containing droplets gradually increases; the flue gas inlet is composed of an inlet pipe inserted into the side wall of the cylinder, and the inner end of the inlet pipe extends to the center of the cylinder, and the inlet pipe is arranged downwardly from the side wall of the cylinder toward the inner cavity of the cylinder.

2. The cooling, dust removal and mist removal tower according to claim 1, characterized in that: The swirler includes a first inner tube and a first outer tube arranged coaxially, and a plurality of swirl blades are circumferentially spaced between the first inner tube and the first outer tube; the bottom end of the first inner tube is connected to the top end of the head, and the bottom end of the first outer tube is connected to the top end of the reducing tube.

3. The cooling, dust removal and mist removal tower according to claim 2, characterized in that: The float demister includes a coaxially arranged second inner tube and a second outer tube, an annular bottom wire mesh is connected to the bottom ends of the second inner tube and the second outer tube, and the annular bottom wire mesh is connected to the top ends of the first inner tube and the first outer tube; an annular top wire mesh is detachably connected to the top ends of the second inner tube and the second outer tube, and a plurality of floats are provided in an annular cavity surrounded by the second inner tube, the second outer tube, the annular bottom wire mesh and the annular top wire mesh.

4. The cooling, dust removal and mist removal tower according to claim 3, characterized in that: A spherical sealing plate is provided at the top end of the second inner tube, and the spherical surface of the spherical sealing plate is protruding upward.

5. The cooling, dust removal and mist removal tower according to claim 3, characterized in that: The dust and mist removal device also includes an expansion pipe arranged above the float demister and with a diameter gradually expanding upward. A lower cleaner is provided in the expansion pipe, and the lower cleaner has multiple lower nozzles with nozzles facing downward. The top and bottom ends of the expansion pipe are respectively connected to the cylinder and the second outer tube.

6. The cooling, dust removal and mist removal tower according to claim 1, characterized in that: A deflecting water retainer is further provided in the cylinder and between the dust and mist removal device and the smoke outlet.

7. The cooling, dust removal and mist removal tower according to claim 6, characterized in that: An upper washer is provided in the cylinder and between the dust and mist removal device and the deflection water retainer. The upper washer has a plurality of upper nozzles with the nozzles facing upward.

8. The cooling, dust removal and mist removal tower according to claim 1, characterized in that: The top of the cylinder is an outlet pipe with a diameter that gradually decreases upwards, and the top end of the outlet pipe constitutes the smoke outlet.

9. The cooling, dust removal and mist removal tower according to claim 1, characterized in that: The sewage discharge mechanism includes a tapered tube whose diameter gradually decreases from top to bottom. The tapered tube is located below the flue gas inlet, and the top end of the tapered tube is connected to the inner wall of the cylinder. The bottom end of the tapered tube is connected to the first end of a sewage discharge pipe, and the second end of the sewage discharge pipe passes through the side wall of the cylinder and extends to the outside of the cylinder.

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