A hydrogen fluoride adsorption column

Abstract

The application relates to the field of hydrogen fluoride adsorption technology, and discloses a hydrogen fluoride adsorption tower, which comprises a tower body, an air inlet pipeline arranged at the lower section of the tower body, an air outlet pipeline arranged at the upper section of the tower body, a plurality of adsorption beds arranged in the tower body in the vertical direction, adsorbents arranged on the adsorption beds, a material replacement mechanism, a plurality of inverted conical funnels arranged below the adsorption beds, and a plurality of capture boxes arranged on the waste pipeline, wherein the waste pipeline penetrates all the adsorption beds, a plurality of spiral scrapers for driving the radial flow of the adsorbents are arranged on the waste pipeline, the upper end of the inverted conical funnel exceeds the outer edge of the adsorption bed, a ring-shaped air outlet is arranged at the bottom outlet of the inverted conical funnel, and the capture boxes are arranged in a ring-shaped array around the waste pipeline. The application has the beneficial effect that the saturated alumina can be separated in time, and the adsorption effect of the alumina is improved.

Description

Technical Field

[0001] This invention relates to the field of hydrogen fluoride adsorption technology, and specifically to a hydrogen fluoride adsorption tower. Background Technology

[0002] A hydrogen fluoride adsorption tower is an industrial gas treatment device that uses activated alumina as an adsorbent to remove hydrogen fluoride (HF) from waste gas through a purification process primarily driven by chemical reactions. Its core function is to efficiently treat HF-containing toxic waste gases generated by industries such as phosphate fertilizers, electrolytic aluminum, fluorochemicals, and semiconductors, preventing environmental pollution and equipment corrosion. The key to this technology lies in the fact that activated alumina does not rely solely on physical adsorption, but rather utilizes its abundant active sites to undergo a strong surface chemical reaction with HF molecules, generating stable compounds such as aluminum fluoride (AlF3), thereby achieving irreversible chemical capture and fixation of HF. This chemical adsorption mechanism results in high HF removal efficiency, large capacity, and strong binding. The adsorbent, after adsorption saturation, can be regenerated through heating and other methods for recycling. During regeneration, the captured fluorine can be recovered in an enriched form, combining environmental benefits with resource potential. Therefore, the adsorption tower is a crucial unit for achieving deep treatment and resource recycling of fluoride pollution.

[0003] Patent document CN212663127U discloses an adsorption tower, including a tower body with an adsorption chamber. The adsorption tower has an inlet and an outlet respectively connected to the adsorption chamber. Several layers of sieve plate structures are arranged at intervals along the direction of gravity within the adsorption chamber. The sieve plate structures are used to block the adsorbent while allowing gas to pass through, so that a mixed gas containing hydrogen enters the adsorption chamber from the inlet, passes through the sieve plate structures, and exits through the outlet. Furthermore, when the mixed gas passes through the adsorbent layers, impurities other than hydrogen can be absorbed by the adsorbent. Cavities for filling the adsorbent are formed between adjacent sieve plates, allowing the adsorption chamber, after being filled with adsorbent, to form a first adsorption layer primarily for adsorbing water vapor, a second adsorption layer primarily for adsorbing carbon dioxide and methane, and a third adsorption layer primarily for adsorbing carbon monoxide, all spaced apart. Adjacent adsorption layers are isolated by the sieve plate structure. The inlet is spaced apart from the nearest sieve plate within the adsorption chamber to form an inlet buffer chamber, and the outlet is spaced apart from the nearest sieve plate within the adsorption chamber to form an outlet buffer chamber. Gas distributors are installed at both the inlet and outlet. This design prevents the adsorbent from clogging the inlet or outlet, ensuring gas flow within the adsorption chamber.

[0004] In existing technologies, activated alumina is used as an adsorbent on a sieve plate when treating hydrogen fluoride. However, as hydrogen fluoride rises from the bottom to the top of the column, it needs to pass through the activated alumina. During this process, hydrogen fluoride is gradually adsorbed by the activated alumina, forming aluminum fluoride. Although the density of aluminum fluoride is less than that of alumina, the lower part of the activated alumina comes into contact with hydrogen fluoride first and becomes saturated. However, in the above-mentioned technology, the activated alumina cannot be stirred, and the already adsorbed alumina particles cannot be discharged. Therefore, with the alumina adsorbent being replaced periodically, the adsorbent effect on the sieve plate gradually deteriorates, thereby reducing the adsorption effect on hydrogen fluoride. Summary of the Invention

[0005] This invention provides a hydrogen fluoride adsorption tower, which aims to solve the problem in related technologies that the already adsorbed alumina particles cannot be discharged. Therefore, when the alumina adsorbent is replaced regularly, the effect of the adsorbent on the sieve plate will gradually deteriorate, thereby reducing the adsorption effect on hydrogen fluoride.

[0006] A hydrogen fluoride adsorption tower includes a tower body, an inlet pipe in the lower section of the tower body, an outlet pipe in the upper section of the tower body, and multiple adsorption beds arranged vertically inside the tower body, each adsorbent being disposed on an adsorption bed. The tower also includes:

[0007] The material changing mechanism includes a waste pipe rotatably installed inside the tower, a drive unit for driving the waste pipe to rotate, multiple inverted conical funnels respectively installed below the multi-layer adsorption bed, and multiple collection boxes installed on the waste pipe. The waste pipe runs through all the adsorption beds and is equipped with multiple spiral scrapers for driving the radial flow of the adsorbent. The upper end of the inverted conical funnel extends beyond the outer edge of the adsorption bed, and an annular air jet is provided at the bottom outlet of the inverted conical funnel. At the position corresponding to the outlet of each inverted conical funnel, the collection boxes are arranged in a ring array around the waste pipe. The outer side of the collection box is provided with a collection port, and a discharge component is provided on the collection box. An arc-shaped sealing baffle for sealing the collection port is fixedly installed on the inverted conical funnel.

[0008] After the adsorbent passes through the jet nozzle, the saturated adsorbent with a relatively low density is blown into the collection port. When the collection port is completely sealed by the arc-shaped sealing baffle, the discharge assembly discharges the saturated adsorbent in the collection box into the waste pipe.

[0009] Its effects are as follows: This device uses a circular arc sealing baffle and a vertical gate with an inverted L-shaped lifting part to work together to first seal the outer opening and then open the inner door during collection. This ensures that the collection box is physically isolated from the toxic environment inside the tower before connecting to the waste pipe for unloading, thereby cutting off the path for hydrogen fluoride gas to enter the emission channel and ensuring airtightness during continuous discharge. At the same time, it utilizes the characteristic that the density of the adsorbent decreases after adsorption saturation, combined with the lateral airflow field at the outlet of the inverted conical funnel for sorting. This allows low-density saturated particles to be carried into the collection box by the airflow and discharged, while high-density unsaturated particles continue to fall under the influence of gravity to participate in the reaction, thus avoiding the waste of adsorbent.

[0010] Preferably, the waste pipe has a feed window on its side wall corresponding to each collection box. The discharge assembly includes a vertical gate that is slidably installed inside the collection box in a vertical direction. The vertical gate seals the space between the feed window and the collection box. The top of the vertical gate extends out of the collection box and forms an inverted L-shaped lifting part. The top of the arc-shaped sealing baffle is provided with a driving boss. When the collection box rotates to the point where the collection port is completely sealed by the arc-shaped sealing baffle, the lifting part that rotates with the waste pipe abuts against the driving boss. The driving boss pushes the lifting part to rise, thereby driving the vertical gate to rise, so that the collection box and the waste pipe are connected.

[0011] Its effect is as follows: through the linkage between the inverted L-shaped lifting part and the driving boss, and in conjunction with the sliding opening and closing of the vertical gate, a collection process of first external sealing and then internal opening is achieved. When the collection box rotates into the shielding area of ​​the arc-shaped sealing baffle, that is, after the outer collection port of the collection box is completely physically sealed and the internal space of the collection box is completely isolated from the toxic gas environment inside the tower, the driving boss will contact the inverted L-shaped lifting part and lift the vertical gate, opening the unloading channel to the waste pipe. This process avoids the situation where the collection port and the feed window are opened at the same time, thereby cutting off the channel for hydrogen fluoride gas to directly enter the waste pipe and leak to the outside. The inverted L-shaped structure uses the cantilever principle to convert the rotational horizontal force into the vertical lifting force. It has a compact structure, high transmission efficiency, and requires no additional electrical control components. It has extremely high reliability and maintenance-free operation in the high-temperature and corrosive environment inside the tower.

[0012] Preferably, the discharge assembly further includes a reset spring disposed on the vertical gate plate. The upper and lower ends of the reset spring are connected to the top of the collection box and the lifting part, respectively. The reset spring is used to drive the vertical gate plate to reset downward to close the feed window after the lifting part disengages from the drive boss.

[0013] Its effects are as follows: the reset spring, as the power source for the vertical gate to close, improves the response speed and sealing reliability of the discharge assembly. After the lifting part passes the high point of the drive boss, relying solely on gravity for reset may cause the gate to close slowly or even get stuck halfway due to guide rail friction or dust adhesion, resulting in sealing failure. However, the reset spring can provide a constant downward elastic force. When the driving force disappears, the gate falls rapidly under the action of the spring force. Its bottom cutting edge can cut off adsorbent particles that may be stuck at the edge of the feed window, forcibly achieving sealing reset. In addition, the reset spring continuously provides pre-tightening force when the gate is closed, making the gate fit tightly against the sealing surface, preventing the generation of tiny gaps when the equipment vibrates or the air pressure fluctuates. This further ensures the tight isolation between the waste pipe and the tower environment when not unloading, reducing the risk of leakage.

[0014] Preferably, the bottom wall of the collection box is an inclined filter screen with a pore size smaller than the minimum particle size of the adsorbent. The filter screen is used to expel gas from the box and retain the adsorbent when the adsorbent is blown into the collection box.

[0015] Its effects are as follows: The bottom wall of the collection box is designed with an inclined filter screen, which solves the two problems of gas-solid separation and smooth unloading. As a gas-solid separation medium, the filter screen allows the sorting airflow carrying saturated adsorbent into the collection box to pass through and be discharged outside the box and back into the tower space, thereby eliminating the back pressure inside the box. Without the filter screen, the airflow entering the blind box will generate eddies and back pressure, making it difficult for adsorbent particles to enter or causing them to be blown out, which seriously affects the collection efficiency. The presence of the filter screen ensures the smooth flow of airflow, allowing low-density saturated particles to be smoothly sucked in and trapped inside the box. Secondly, the filter screen is set at an incline. Utilizing the principle of gravity, the inclined surface becomes a slide during the unloading stage, which promotes the smooth and complete sliding of the trapped adsorbent particles into the waste pipe, avoiding the accumulation of material in dead corners inside the box. This design realizes the permeable material retention during collection and the self-flowing emptying during unloading, which greatly improves the sorting efficiency and operational stability of the system.

[0016] Preferably, a downwardly extending protective sleeve is fixedly connected to the bottom outlet of the inverted conical funnel. The lower end of the protective sleeve extends above the next layer of adsorption bed with a gap. The protective sleeve covers the outer perimeter of the rotation trajectory of the collection box. An annular air jet is provided on the inner wall of the protective sleeve, and the air jet direction is towards the axis of the waste pipe.

[0017] Its effects are as follows: By setting a downward-extending protective casing, a relatively closed and stable air classification chamber is constructed. The protective casing constrains the adsorbent falling from the inverted conical funnel, preventing particles from splashing randomly in the tower. This ensures that high-density unsaturated adsorbent can fall accurately and vertically into the central area of ​​the next adsorption bed, maintaining the flatness of the bed. The protective casing provides a mounting carrier for the jet nozzle and limits the diffusion range of the sorting airflow, allowing the high-speed airflow to concentrate its energy and penetrate the falling material curtain laterally, improving the purging efficiency of low-density saturated particles. The protective casing covers the periphery of the collection box, forming a physical barrier that protects the rotating collection box from interference from the main airflow in the tower. The centripetal airflow field generated by the annular jet nozzle utilizes the difference in horizontal displacement between saturated and unsaturated adsorbents under the action of the transverse airflow to achieve physical separation.

[0018] Preferably, the inverted conical funnel is provided with a gas-lifting chimney, and the gas-lifting chimney extends through both the upper and lower ends of the inverted conical funnel.

[0019] Its effect is as follows: by adding a through-hole gas-lifting chimney to the inverted conical funnel, the competition for passage between the downward flow of material and the upward flow of gas in the multi-layer adsorption tower is avoided. The gas passes directly through the funnel barrier through the chimney and enters the bottom gas chamber of the upper adsorption bed for redistribution, while the solid adsorbent slides down along the outer wall of the funnel, ensuring the smooth flow and uniform distribution of the airflow throughout the tower, maintaining the efficient state of gas-solid countercurrent contact in the adsorption bed, and preventing the decrease in processing capacity caused by gas resistance.

[0020] Preferably, the adsorption bed includes a hollow water-cooled plate, and a cooling medium flows through the water-cooled plate.

[0021] Its effectiveness lies in the following: the internally hollow, water-cooled plate serves as the support carrier for the adsorption bed, directly optimizing thermal management to address the exothermic chemical characteristic of the reaction between hydrogen fluoride and alumina. During adsorption, the accumulated heat of reaction causes the adsorbent temperature to rise. Furthermore, localized high temperatures can lead to sintering and caking of the adsorbent, damaging the bed structure. By circulating cooling water inside the sieve plate, heat from the bottom of the adsorption bed can be removed immediately and at close range, maintaining the bed within a lower, suitable reaction temperature range. This not only improves the equilibrium adsorption capacity and purification efficiency of the adsorbent and extends its service life, but also effectively prevents safety hazards caused by heat accumulation, ensuring the stable operation of the adsorption tower under high-load conditions.

[0022] Preferably, the drive unit includes a motor and a reducer disposed at the top of the tower body, with the input end of the motor connected to the output end of the reducer, and the top end of the waste pipe connected to the output end of the reducer.

[0023] The advantages are as follows: placing the drive unit at the top of the tower and directly driving the central waste pipe to rotate serves four purposes: first, as a discharge channel for saturated waste; second, as a mounting base for internal components such as the spiral scraper and collection box; third, as a rotary drive shaft for transmitting torque; and fourth, as a heat sink within the tower. Driving the waste pipe with a top-mounted motor avoids the need for complex transmission and sealing structures at the bottom of the tower, reducing potential leakage points. Simultaneously, this central single-shaft drive method results in an extremely compact internal structure, eliminating synchronization problems and potential mechanical failures associated with multi-shaft drives, and reducing manufacturing costs and maintenance complexity.

[0024] Preferably, a fresh material supply pipe is provided at the top of the tower body, and the fresh material supply pipe supplies adsorbent to the center of the uppermost adsorption bed.

[0025] Its effects are as follows: Fresh adsorbent is fed to the center of the uppermost adsorption bed through the top feed pipe, and combined with the centrifugal pushing action of the spiral scraper, the adsorbent enters from the top and exits from the bottom, entering from the center and exiting from the edge. Fresh adsorbent first enters the uppermost layer, contacting the lowest concentration of the tail gas, ensuring extremely low concentration indicators for the outlet gas. As the adsorbent moves down layer by layer, its adsorption saturation gradually increases, eventually contacting the high-concentration inlet gas at the bottom, fully utilizing its adsorption capacity. Simultaneously, the center-feeding method utilizes the characteristic of the spiral scraper pushing the material from the inside out, ensuring that the movement path length of each adsorbent particle on the bed is basically consistent, and the residence time is uniform, effectively avoiding short circuits and dead zones, ensuring that all adsorbent is fully utilized.

[0026] Preferably, the inner arc surface of the arc sealing baffle is provided with a wear-resistant sealing strip, which is fitted and sealed to the outer surface of the collection box.

[0027] Its effect is as follows: Adding a wear-resistant sealing strip (such as one filled with polytetrafluoroethylene or special rubber material) to the inner arc surface of the arc sealing baffle is to achieve zero leakage under rotating dynamic sealing conditions. Since the collection box rotates with the waste pipe while the baffle is stationary, there is relative motion between the two. Direct contact between metal and metal not only makes it difficult to ensure airtightness, but also leads to severe wear and jamming. The wear-resistant sealing strip has a certain elastic compensation ability, which can fill the processing error and assembly gap, ensuring that the outer collection port is tightly sealed when the collection box rotates into the baffle area. At the same time, the wear-resistant material has a low coefficient of friction, which reduces rotational resistance and extends the service life of the sealing structure.

[0028] The beneficial effects of this invention using the above technical solution are as follows: This device, through the cooperation of an arc-shaped sealing baffle and a vertical gate with an inverted L-shaped lifting section, constructs a mechanical airlock system that strictly follows the sequential logic of "first sealing the outer opening, then opening the inner door." This ensures that the collection box is physically isolated from the toxic environment inside the tower before connecting to the waste pipe for unloading, thereby effectively cutting off the path for hydrogen fluoride gas to enter the emission channel and solving the airtightness problem during continuous discharge. Simultaneously, utilizing the characteristic that the density of the adsorbent decreases significantly after adsorption saturation, combined with the lateral airflow field at the outlet of the inverted conical funnel for online sorting, low-density saturated particles are carried into the collection box by the airflow and discharged, while high-density unsaturated particles continue to fall under gravity to participate in the reaction, avoiding waste of the adsorbent. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the overall structure of the present invention.

[0030] Figure 2 This is a cross-sectional view of the overall structure of the present invention.

[0031] Figure 3 This is a front view of the adsorption bed of the present invention.

[0032] Figure 4 This is a front view of the inverted conical funnel of the present invention.

[0033] Figure 5 for Figure 4 Enlarged view of point A in the middle.

[0034] Figure 6 This is a front view of the waste pipe of the present invention.

[0035] Figure 7 This is a top view of the inverted conical funnel of the present invention.

[0036] Figure label:

[0037] 1. Tower body; 2. Adsorption bed; 4. Waste pipe; 41. Feed window; 5. Drive component one; 6. Spiral scraper; 7. Inverted conical funnel; 71. Gas lifting chimney; 72. Gas nozzle; 73. Gas pipe; 74. Guide platform; 8. Collection box; 81. Collection port; 82. Vertical gate; 83. Lifting part; 84. Reset spring; 85. Filter screen; 9. Arc sealing baffle; 91. Drive boss; 10. Casing. Detailed Implementation

[0038] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0039] like Figures 1-7As shown, an embodiment of the present invention provides a hydrogen fluoride adsorption tower, comprising a tower body 1, an adsorption bed 2, a material changing mechanism, and inlet and outlet gas pipes. The tower body 1, serving as the outer shell of the entire device, is typically constructed from corrosion-resistant stainless steel through rolling and welding, capable of withstanding internal pressure and corrosive gas environments. An inlet pipe is provided on the lower side wall of the tower body 1 to introduce waste gas containing hydrogen fluoride into the tower; an outlet pipe is provided on the top or upper side wall of the tower body 1, through which the clean gas purified by adsorption is discharged.

[0040] like Figure 1 and Figure 2 As shown, multiple adsorption beds 2 are arranged vertically from bottom to top within the internal space of the tower body 1. These adsorption beds 2 divide the inner cavity of the tower body 1 into several independent reaction chambers. The adsorption beds 2 are in the shape of a ring plate, with their outer edges fixedly welded to the inner wall of the tower body 1. Adsorbent is laid on the adsorption beds 2, preferably activated alumina spheres, which have a rich microporous structure and can efficiently adsorb hydrogen fluoride gas. In this embodiment, the adsorption beds 2 adopt an internally hollow water-cooled plate structure, with cooling channels opened inside the water-cooled plate. Cooling water is introduced into the channels through circulating water pipes outside the tower body 1. Since the reaction between hydrogen fluoride and alumina is a strongly exothermic reaction, if a large amount of reaction heat cannot be dissipated in time, it will cause the bed temperature to rise, thereby reducing the adsorption capacity of the adsorbent and even causing the adsorbent to sinter. Through the design of the water-cooled plate, the reaction heat can be removed in time, maintaining the bed within a suitable temperature range, ensuring adsorption efficiency and the service life of the adsorbent.

[0041] like Figures 1-7 As shown, the present invention also includes a material replacement mechanism for realizing continuous replacement and automatic sorting of the adsorbent. The material replacement mechanism includes a waste pipe 4, a drive component 5, a spiral scraper 6, an inverted conical funnel 7, and a collection box 8. The waste pipe 4 is a large-diameter, thick-walled steel pipe located at the axis of the tower body 1. It coaxially runs through all the adsorption beds 2, and its bottom end extends through the bottom of the tower body 1 to the outside. The waste pipe 4 performs a dual function in the present invention: on the one hand, it is the only physical channel for the discharge of saturated adsorbent; on the other hand, it is the drive shaft for the rotating components in the entire tower. On the outer wall of the waste pipe 4, corresponding to the position above each layer of adsorption bed 2, multiple spiral scrapers 6 are welded and fixed. The spiral scrapers 6 are logarithmic spirals or involutes in shape, and their bottom surfaces are attached to the upper surface of the adsorption bed 2. When the waste pipe 4 rotates, the spiral scraper 6 can slowly and evenly push the adsorbent accumulated on the adsorption bed 2 from the inner ring to the outer ring, forcing the adsorbent to generate radial flow on the bed, avoiding dead corners, and realizing the "first-in, first-out" replacement logic.

[0042] The drive unit 5 is mounted on the top platform of the tower body 1 and includes a motor (not shown in the figure) and a reducer (not shown in the figure). The input end of the motor is connected to the power supply, and the output end is connected to the input end of the reducer. The output end of the reducer is fixedly connected to the top of the waste pipe 4 via a coupling, thereby driving the waste pipe 4 to rotate continuously in one direction at a very low speed. A fresh material supply pipe is also provided at the top of the tower body 1 to replenish new adsorbent to the central area of ​​the uppermost adsorption bed 2 to maintain the dynamic balance of materials inside the tower.

[0043] like Figure 3 As shown, an inverted conical funnel 7 is provided below each layer of adsorption bed 2. The inverted conical funnel 7 is a funnel-shaped material guiding component with a larger opening diameter at the upper end, extending beyond the outer edge of the previous layer of adsorption bed 2, used to collect the adsorbent pushed down from the edge of the previous layer of adsorption bed 2 by the spiral scraper 6. The smaller opening diameter at the lower end of the inverted conical funnel 7 is used to re-aggregate the collected adsorbent and guide it to the central area of ​​the next layer of adsorption bed 2, thereby completing the material circulation path of "center in - edge out - falling into the funnel - center in".

[0044] Multiple gas-lifting chimneys 71 are interspersed on the conical surface of the inverted conical funnel 7. Each gas-lifting chimney 71 is a vertical tubular structure that penetrates both the upper and lower walls of the inverted conical funnel 7. The upper opening of the gas-lifting chimney 71 is located above the material accumulation surface inside the inverted conical funnel 7, and the lower opening is located in the lower space outside the inverted conical funnel 7. In this way, the gas rising from the lower layer can directly pass through the funnel layer via the gas-lifting chimneys 71 and enter the bottom inlet chamber of the upper adsorption bed 2, achieving physical separation of the gas and solid flow channels, reducing system resistance, and ensuring smooth gas flow. A flow guide platform 74 is installed inside the inverted conical funnel 7, corresponding to the arc-shaped sealing baffle 9, used to guide the adsorbent flowing towards the arc-shaped sealing baffle 9 to the side of the arc-shaped sealing baffle 9.

[0045] like Figures 3-7 As shown, at the bottom outlet of the inverted conical funnel 7, a downwardly extending protective casing 10 is fixedly connected by a flange or welding. The protective casing 10 has a cylindrical structure, with its lower end extending above the next adsorption bed 2, leaving a height gap (e.g., 50-100 mm) for the adsorbent to flow out. The function of the protective casing 10 is to constrain the falling material flow and create a relatively closed sorting air field area. An annular jet nozzle 72 is provided on the inner wall of the protective casing 10. The jet nozzle 72 is connected to an external high-pressure blower or compressed air source through a jet pipe 73. The jet direction of the jet nozzle 72 is horizontally directed towards the axis of the waste pipe 4.

[0046] As the adsorbent slides down the inverted conical funnel 7 into the area of ​​the protective casing 10, it forms an annular drop curtain. At this time, the adsorbent must pass through the plane where the jet nozzle 72 is located. The saturated adsorbent, which has adsorbed HF and converted it into aluminum fluoride, undergoes a change in its crystal structure and its density decreases. The unreacted activated alumina has a higher density. Under the purging of the lateral high-speed airflow, the saturated adsorbent with a relatively lower density is more affected by the aerodynamic force, resulting in a larger horizontal displacement and drifting further towards the waste pipe 4. The unsaturated adsorbent with a relatively higher density drifts closer towards the waste pipe 4, thus passing vertically through the protective casing 10 and accumulating in the center of the next adsorption bed 2 to continue participating in the reaction.

[0047] like Figure 4 and Figure 5 As shown, to capture and seal the saturated adsorbent blown out by the airflow, multiple collection boxes 8 are welded and fixed to the outer wall of the waste pipe 4 at the height corresponding to the outlet of each inverted conical funnel 7. These collection boxes 8 are evenly distributed radially around the waste pipe 4 and rotate with it. The collection box 8 is a metal box with an open collection port 81 on the side facing the inner wall of the casing 10. The saturated adsorbent blown in by the airflow enters the collection box 8 through the collection port 81. To facilitate the passage of the airflow and the interception of the material, the bottom wall of the collection box 8 is designed as an inclined filter screen 85. The mesh size of the filter screen 85 is selected so that its pore size is smaller than the minimum particle size of the adsorbent. When the airflow carrying the saturated adsorbent is blown into the collection port 81, the gas passes through the filter screen 85 and exits the box, returning to the space inside the tower; while the saturated adsorbent particles are intercepted by the filter screen 85 and slide down the inclined surface to accumulate inside the box.

[0048] like Figures 2-7 As shown, a key innovation of this invention lies in solving the interference problem between the rotating component and the fixed sealing component. An arc-shaped sealing baffle 9 is fixedly mounted on the inverted conical funnel 7 via a bracket. The arc-shaped sealing baffle 9 is a steel plate with an arc of approximately 60-90 degrees, and its inner arc surface is adhered with a wear-resistant sealing strip made of Teflon or wear-resistant rubber for sealing against the outer surface of the rotating collection box 8. A height gap exists between the lower end face of the arc-shaped sealing baffle 9 and the upper surface of the next layer of adsorption bed 2. The height of the spiral scraper 6 fixed at the root of the waste pipe 4 is lower than this gap. Therefore, when the waste pipe 4 drives the spiral scraper 6 to rotate and push material, the spiral scraper 6 can pass under the arc-shaped sealing baffle 9 to scrape the adsorption bed 2 from all directions.

[0049] like Figure 4 , Figure 5 and Figure 6As shown, a discharge assembly is provided at the connection between the collection box 8 and the waste pipe 4. A rectangular feed window 41 is provided on the wall of the waste pipe 4, corresponding to the internal position of each collection box 8. The discharge assembly includes a vertical gate 82, which is slidably installed in a guide groove on the inner side wall of the collection box 8. The vertical gate 82 is larger than the feed window 41 and is used to block the window. The top of the vertical gate 82 extends upward through the top plate of the collection box 8 and is bent to form an inverted L-shaped lifting part 83. A return spring 84 is fitted on the rod of the vertical gate 82 located outside the collection box 8. The return spring 84 is in a compressed state, with its upper end abutting the lower surface of the lifting part 83 and its lower end abutting the top surface of the collection box 8. Under normal conditions, the elastic force of the return spring 84 presses the vertical gate 82 downward, tightly covering the feed window 41 and keeping it closed.

[0050] A drive boss 91 is fixedly provided on the top of the arc-shaped sealing baffle 9. The drive boss 91 is a metal block with a rising slope, a horizontal holding surface, and a falling slope. Its position is precisely calculated so that the drive boss 91 will only begin to contact the inverted L-shaped lifting part 83 after the collection box 8 rotates into the blocking range of the arc-shaped sealing baffle 9 (i.e., the collection port 81 is completely sealed).

[0051] The working process of this invention is as follows:

[0052] The waste pipe 4 rotates slowly under the drive of the drive component 5. The adsorbent on the adsorption bed 2 comes into contact with and reacts with the rising hydrogen fluoride gas. The spiral scraper 6 rotates with the waste pipe 4, pushing the adsorbent from the inner ring to the outer ring, causing it to fall into the inverted conical funnel 7. The adsorbent slides down the inverted conical funnel 7 into the area of ​​the protective cylinder 10. At this time, the adsorbent passes through the jet nozzle 72. Due to the lower density of the saturated adsorbent, it undergoes a large horizontal displacement under the lateral airflow and is blown into the collection port 81 and enters the collection box 8; while the unsaturated adsorbent has a higher density and falls vertically under the influence of gravity, passing through the protective cylinder 10 and falling onto the next layer of adsorption bed 2 for continued use. The gas is discharged from the collection box 8 through the filter screen 85. After collecting the saturated adsorbent, the collection box 8 continues to rotate with the waste pipe 4. When the collection box 8 rotates to the position of the arc-shaped sealing baffle 9, the collection port 81 is completely blocked and sealed by the arc-shaped sealing baffle 9. At this point, the gas environment inside the collection box 8 is physically isolated from that inside the tower body 1. After the seal is established, the bottom of the cantilever end of the inverted L-shaped lifting part 83, which rotates with the waste pipe 4, contacts the rising slope of the fixed drive boss 91. As the rotation continues, the drive boss 91 pushes the lifting part 83 upward, thereby causing the vertical gate 82 to slide upward and open. At this time, the inside of the collection box 8 is connected to the inside of the waste pipe 4 through the feed window 41. Under the action of gravity, the saturated adsorbent in the box slides down the inclined filter screen 85 into the waste pipe 4. Since the collection port 81 is sealed at this time, the fluorine-containing gas in the tower body 1 cannot enter the collection box 8, and therefore cannot enter the waste pipe 4, achieving absolute sealed discharge. After the collection box 8 rotates past the holding platform section of the drive boss 91, the waste has been discharged. Then it enters the descending slope section, and the lifting part 83 loses its support. The reset spring 84 releases its elastic force, driving the vertical gate 82 to quickly reset downward, closing the feed window 41 again. Immediately afterwards, the collection box 8 rotates out of the area of ​​the arc-shaped sealing baffle 9, and the collection port 81 reopens, ready for the next round of collection.

[0053] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A hydrogen fluoride adsorption tower, comprising a tower body, an inlet pipe in the lower section of the tower body, an outlet pipe in the upper section of the tower body, and multiple adsorption beds arranged vertically inside the tower body, wherein adsorbent is disposed on the adsorption beds, characterized in that... Also includes: The material changing mechanism includes a waste pipe rotatably mounted inside the tower, a drive unit for rotating the waste pipe, multiple inverted conical funnels respectively positioned below the multi-layer adsorption beds, and multiple collection boxes mounted on the waste pipe. The waste pipe penetrates all the adsorption beds and is equipped with multiple spiral scrapers for driving the radial flow of the adsorbent. The upper end of the inverted conical funnel extends beyond the outer edge of the adsorption bed, and an annular jet nozzle is provided at the bottom outlet of the inverted conical funnel. At the outlet position corresponding to each stage of the inverted conical funnel, the collection boxes are arranged in a circular array around the waste pipe. The outer side of the collection boxes has a collection port, and a discharge component is provided on the collection boxes. An arc-shaped sealing baffle is fixedly installed on the top for sealing the collection port; a feed window is opened on the side wall of the waste pipe at the position corresponding to each collection box; the discharge assembly includes a vertical gate plate that is slidably installed on the inside of the collection box in the vertical direction. The vertical gate plate seals between the feed window and the collection box. The top of the vertical gate plate extends out of the collection box and forms an inverted L-shaped lifting part. A driving boss is provided on the top of the arc-shaped sealing baffle plate. When the collection box rotates to the point where the collection port is completely sealed by the arc-shaped sealing baffle plate, the lifting part that rotates with the waste pipe abuts against the driving boss. The driving boss pushes the lifting part to rise, thereby driving the vertical gate plate to rise, so that the collection box and the waste pipe are connected. After the adsorbent passes through the jet nozzle, the saturated adsorbent with a relatively low density is blown into the collection port. When the collection port is completely sealed by the arc sealing baffle, the discharge assembly discharges the saturated adsorbent in the collection box into the waste pipe. The discharge assembly also includes a reset spring mounted on the vertical gate. The upper and lower ends of the reset spring are connected to the top of the collection box and the lifting part, respectively. The reset spring is used to drive the vertical gate to reset downwards to close the feed window after the lifting part disengages from the drive boss.

2. The hydrogen fluoride adsorption tower according to claim 1, characterized in that, The bottom wall of the collection box is an inclined filter screen with a pore size smaller than the minimum particle size of the adsorbent. The filter screen is used to expel gas from the box and retain the adsorbent when the adsorbent is blown into the collection box.

3. The hydrogen fluoride adsorption tower according to claim 1, characterized in that, A downward-extending protective sleeve is fixedly connected to the bottom outlet of the inverted conical funnel. The lower end of the protective sleeve extends above the next layer of adsorption bed with a gap. The protective sleeve covers the outer perimeter of the rotation trajectory of the collection box. An annular air jet is opened on the inner wall of the protective sleeve, and the air jet direction is towards the axis of the waste pipe.

4. The hydrogen fluoride adsorption tower according to claim 1, characterized in that, The inverted conical funnel is equipped with a gas-lifting chimney, which extends through both the upper and lower ends of the inverted conical funnel.

5. A hydrogen fluoride adsorption tower according to claim 1, characterized in that, The adsorption bed includes a hollow water-cooled plate, and a cooling medium flows through the water-cooled plate.

6. The hydrogen fluoride adsorption tower according to claim 1, characterized in that, The drive unit includes a motor and a reducer located at the top of the tower body. The input end of the motor is connected to the output end of the reducer, and the top end of the waste pipe is connected to the output end of the reducer.

7. A hydrogen fluoride adsorption tower according to claim 1, characterized in that, A fresh material supply pipe is provided at the top of the tower body, which replenishes the adsorbent to the center of the uppermost adsorption bed.

8. A hydrogen fluoride adsorption tower according to claim 1, characterized in that, The inner arc surface of the circular arc sealing baffle is provided with a wear-resistant sealing strip, which is fitted and sealed to the outer surface of the collection box.

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