Recovery device for silicon tetrafluoride and hydrogen fluoride preparation system
By setting a bottom inlet in the rotary drum vacuum filter to agitate the liquid, the stability and safety issues caused by the oscillating agitator are solved, achieving higher equipment stability and safety.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-24
- Publication Date
- 2026-03-20
AI Technical Summary
Existing rotary drum filters require the installation of oscillating agitators, resulting in poor filter stability and affecting the stability and safety of equipment operation.
In a rotary drum vacuum filter, the inlet is located at the bottom of the filtration space. The fluorosilicic acid solution is stirred by inputting liquid, keeping the silica solid in a suspended state. This eliminates the need for a swing-type agitator and simplifies the structure.
It improves the stability and safety of the filter, simplifies the equipment structure, reduces the possibility of failure, and avoids the risk of fluorosilicic acid solution leakage.
Smart Images
Figure CN224009233U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The application belongs to the technical field of filtering equipment, and particularly relates to a recovery device for silicon tetrafluoride and a hydrogen fluoride preparation system. BACKGROUND
[0002] In the process of hydrogen fluoride preparation, part of fluorine will escape in the form of silicon tetrafluoride gas. If the silicon tetrafluoride gas is treated as waste gas, the conversion rate of hydrogen fluoride will be low, and the cost of equipment for treating waste gas will be increased. Therefore, an equipment capable of absorbing and reusing the silicon tetrafluoride gas is needed. At present, the equipment for absorbing the silicon tetrafluoride gas uses the property that the silicon tetrafluoride gas is soluble in water to absorb the silicon tetrafluoride. After the silicon tetrafluoride is absorbed, silicon dioxide solid and fluorosilicic acid solution are generated, and the silicon dioxide solid and the fluorosilicic acid solution need to be separated, for example, a drum filter is used for filtering.
[0003] In the filtering process of the existing drum filter, in order to ensure that the silicon dioxide solid in the fluorosilicic acid solution remains in a suspended state, a swing stirring paddle is usually arranged in the region where the fluorosilicic acid solution is located to stir. However, the swing of the stirring paddle will cause poor stability of the filter, and affect the stability and safety of the whole equipment. CONTENT OF THE UTILITY MODEL
[0004] The technical problem to be solved by the present application is that the swing stirring paddle needs to be arranged in the existing drum filter to stir, which causes poor stability of the filter. To solve the technical problem, a recovery device for silicon tetrafluoride and a hydrogen fluoride preparation system with high stability and safety are provided.
[0005] The technical solution provided by the present application is as follows:
[0006] A recovery device for silicon tetrafluoride, comprising:
[0007] An input mechanism for inputting a gas containing silicon tetrafluoride;
[0008] An absorption mechanism connected with the input mechanism for absorbing the silicon tetrafluoride and forming a fluorosilicic acid solution containing silicon dioxide;
[0009] A drum vacuum filter, comprising:
[0010] A shell having an inner cavity, wherein the bottom of the inner cavity is provided with a filtering space;
[0011] A drum rotatably arranged in the inner cavity;
[0012] The bottom of the filtering space is provided with a liquid inlet, the absorption mechanism is in communication with the liquid inlet, the fluorosilicic acid solution containing silicon dioxide is input into the filtering space, and the bottom of the drum is immersed in the fluorosilicic acid solution.
[0013] With the recycling device, the fluorosilicic acid solution is filtered in the filtering space, and as the liquid inlet is located at the bottom of the filtering space, the input liquid can agitate the fluorosilicic acid solution in the filtering space when the fluorosilicic acid solution is input, so that the silicon dioxide solids in the fluorosilicic acid solution are kept in a suspended state, and it is not necessary to set a swing type stirring paddle for stirring. In this way, the structure of the rotary drum type vacuum filter is simplified, and the stability of the filter can be improved, so that the stability and safety of the operation of the entire recycling device are improved.
[0014] Further, the inner cavity comprises a filtering area, a cleaning area and a discharging area arranged along the rotation direction of the rotary drum, and the filtering space is located at the bottom of the filtering area.
[0015] The outer side of the rotary drum in the filtering area part can form a filter cake, and in the process of rotation of the rotary drum, the filter cake on the outer side of the rotary drum can pass through the cleaning area and the discharging area, and the filter cake can be separated from the rotary drum in the discharging area.
[0016] The rotary drum type vacuum filter further comprises a cleaning member arranged in the cleaning area and used for cleaning the filter cake passing through the cleaning area.
[0017] Further, the inner cavity further comprises a first drying area and a second drying area, and the filtering area, the first drying area, the cleaning area, the second drying area and the discharging area are arranged along the rotation direction of the rotary drum.
[0018] Further, the inner cavity further comprises a back blowing area located between the second drying area and the discharging area.
[0019] The rotary drum type vacuum filter further comprises a back blowing member at least partially arranged in the back blowing area and extending into the rotary drum, and the back blowing member is used for blowing air towards the inner side of the rotary drum located in the back blowing area.
[0020] Further, the rotary drum type vacuum filter further comprises a scraper arranged in the discharging area and used for scraping the filter cake passing through the discharging area away from the rotary drum.
[0021] Further, the filtering space comprises a bottom wall and bottom side walls connected to opposite sides of the bottom wall, and the two bottom side walls extend away from each other, and the liquid inlet is arranged at the bottom of the bottom side wall.
[0022] Further, the bottom of each bottom side wall is provided with the liquid inlet.
[0023] Further, a raw liquid tank and a vacuum generator are further included, the raw liquid tank is communicated with the inside of the rotary drum, and the vacuum generator is connected with the raw liquid tank.
[0024] Further, an air induction fan is further included, and the air induction fan is connected with the shell.
[0025] A hydrogen fluoride preparation system comprises the recovery device for silicon tetrafluoride as described above. BRIEF DESCRIPTION OF DRAWINGS
[0026] The accompanying drawings are included to provide a further understanding of the present application, and constitute a part of the specification, illustrate the embodiments of the present application, and are used to explain the present application, and do not constitute a limitation on the present application.
[0027] Figure 1 A structural schematic diagram of a rotary drum vacuum filter is provided for an embodiment of the present application.
[0028] Figure 2 For Figure 1 A cross-sectional structural schematic diagram of a filtering space in the rotary drum vacuum filter is shown.
[0029] Label explanation:
[0030] 110, shell; 111, filtering space; 112, liquid inlet; 113, bottom wall; 114, bottom side wall; 120, vacuum generator; 130, raw liquid tank; 140, liquid storage tank. DETAILED DESCRIPTION
[0031] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.
[0032] In the description of the present application, it should be understood that the terms “center”, “longitudinal”, “transverse”, “length”, “width”, “thickness”, “upper”, “lower”, “front”, “rear”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inner”, “outer”, “clockwise”, “counterclockwise” and the like indicate the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application.
[0033] In one aspect, the application discloses a recovery device for silicon tetrafluoride, which comprises an input mechanism, an absorption mechanism and a drum vacuum filter. The input mechanism is connected with the absorption mechanism and used for inputting a gas containing silicon tetrafluoride into the absorption mechanism; and the absorption mechanism is used for absorbing the silicon tetrafluoride and forming a fluorosilicic acid solution containing silicon dioxide. Optionally, the input mechanism can be a gas storage tank used for collecting the silicon tetrafluoride gas leaked in the process of preparing hydrogen fluoride; and the absorption mechanism can adopt a gas absorption tower.
[0034] As shown in Figure 1 and Figure 2 , the drum vacuum filter comprises a shell 110 and a drum. The shell 110 has an inner cavity, and the bottom of the inner cavity is provided with a filtering space 111. The bottom of the filtering space 111 is provided with a liquid inlet 112, and the absorption mechanism is communicated with the liquid inlet 112 to input the fluorosilicic acid solution containing silicon dioxide into the filtering space 111. The bottom of the drum is immersed in the fluorosilicic acid solution to filter the fluorosilicic acid solution.
[0035] By using the above recovery device, the fluorosilicic acid solution is filtered in the filtering space 111, and since the liquid inlet 112 is located at the bottom of the filtering space 111, the input liquid can stir the fluorosilicic acid solution in the filtering space 111 when the fluorosilicic acid solution is inputted, so that the silicon dioxide solid in the fluorosilicic acid solution can be kept in a suspended state without setting a swing stirring paddle to stir. In this way, the structure of the drum vacuum filter is simplified, and the stability of the filter can be improved, thereby improving the stability and safety of the operation of the whole recovery device.
[0036] It should be explained that setting a swing stirring paddle in the filter can increase the complexity of the structure, increase the possibility of failure, and easily increase the possibility of leakage of the fluorosilicic acid solution in the filter, and the fluorosilicic acid is a strong acid solution. Therefore, canceling the swing stirring paddle can increase the stability of the filter and the stability and safety of the operation of the recovery device.
[0037] It should be further explained that in the embodiment, the drum vacuum filter is applied to the filtration of the fluorosilicic acid solution containing silicon dioxide. Since the fluorine ion can adsorb and change the surface charge of silicon dioxide to enhance the electrostatic repulsion, the coordination of the fluorine ion weakens the attraction between the silicon dioxide particles; and the fluorosilicic acid can inhibit the dissolution of silicon dioxide to keep the stability of the silicon dioxide particles. In this way, the silicon dioxide is more likely to form a suspension in the fluorosilicic acid solution, and then the solution can be stirred by setting the liquid inlet 112 at the bottom to keep the silicon dioxide in a suspended state.
[0038] In one embodiment, the recovery device further comprises a raw liquid tank 130 in communication with the interior of the rotary drum, for example through a pipe, and a vacuum generator 120 connected to the raw liquid tank 130, so that the vacuum generator 120 can suck liquid into the interior of the rotary drum, thereby filtering the fluosilicic acid solution, and the filtered liquid in the interior of the rotary drum is input into the raw liquid tank 130.
[0039] In one embodiment, the filtering space 111 comprises a bottom wall 113 and two bottom side walls 114 connected to opposite sides of the bottom wall 113, and the two bottom side walls 114 extend away from each other to form the filtering space 111 with gradually increasing space size from bottom to top. Meanwhile, the liquid inlet 112 is arranged at the bottom of the bottom side wall 114. Since the space size at the bottom of the filtering space 111 is small, the agitation effect of the liquid input through the liquid inlet 112 can be improved, thereby ensuring that the silicon dioxide solids in the fluosilicic acid solution are in a suspended state. Specifically, in the embodiment shown in the drawings, the filtering space 111 has a cross section in the shape of an inverted trapezoid. Figure 2
[0040] Further, the liquid inlet 112 is arranged on each bottom side wall 114, thereby further improving the agitation effect of the liquid in the filtering space 111. In addition, the number of liquid inlets 112 on the two bottom side walls 114 can be multiple, and they can be one-to-one corresponding or staggered with each other.
[0041] In other embodiments, the filtering space 111 can also have other shapes as long as the space size of the filtering space 111 gradually increases from bottom to top, and the liquid inlet 112 is arranged at the bottom of the filtering space 111.
[0042] In one embodiment, the inner cavity comprises a filtering zone, a cleaning zone and a discharging zone. The filtering zone, the cleaning zone and the discharging zone are arranged along the rotation direction of the rotary drum. The filtering space 111 is located at the bottom of the filtering zone.
[0043] After the fluosilicic acid solution is filtered in the filtering zone, a filter cake can be formed on the outer side of the rotary drum in the filtering zone. During the rotation of the rotary drum, the filter cake passes through the cleaning zone and the discharging zone, and the filter cake can be separated from the rotary drum in the discharging zone, thereby achieving the discharging of the filter cake.
[0044] Further, the rotary vacuum filter further comprises a cleaning member and a scraper. The cleaning member is arranged in the cleaning zone and is used to clean the filter cake passing through the cleaning zone, thereby washing away the residual acidic substances on the filter cake, and under the action of negative pressure, the cleaned liquid is sucked into the interior of the rotary drum and discharged. The scraper is arranged in the discharging zone and is used to scrape the filter cake passing through the discharging zone away from the rotary drum. It should be explained that in this embodiment, the liquid for cleaning the silicon dioxide is water.
[0045] In one embodiment, the inner cavity further comprises a first drying zone and a second drying zone, and the filter zone, the first drying zone, the washing zone, the second drying zone and the discharging zone are arranged in the rotation direction of the rotary drum. The filter cake on the rotary drum is dried in the first drying zone and the second drying zone. Specifically, in the first drying zone and the second drying zone, there is no liquid supplement on the filter cake, and at the same time, under the action of negative pressure, the gas in the inner cavity enters the inside of the rotary drum through the filter cake. When the gas flows through the filter cake, the liquid remaining on the filter cake is carried into the inside of the rotary drum, thereby realizing the drying of the filter cake. In addition, the filter cake first passes through the first drying zone and then enters the washing zone, so that the residual substances on the filter cake can be reduced before washing, thereby improving the washing effect.
[0046] In one embodiment, the inner cavity further comprises a back flushing zone, and the back flushing zone is located between the second drying zone and the discharging zone. Specifically, the filter zone, the first drying zone, the washing zone, the second drying zone, the back flushing zone and the discharging zone are arranged in the rotation direction of the rotary drum. Further, the rotary drum type vacuum filter further comprises a back flushing member, the back flushing member is at least partially arranged in the back flushing zone and extends into the rotary drum, and the back flushing member is used for blowing gas towards the inside of the rotary drum located in the back flushing zone, so as to blow the surface of the rotary drum to bulge, thereby facilitating the scraper to scrape off the filter cake on the outside.
[0047] In one embodiment, the shell 110 is further provided with an overflow hole, and the overflow hole is located in the filter zone and communicates with the filter space 111. The overflow hole is used to discharge and recover the liquid when the liquid level in the filter space 111 is too high.
[0048] In one embodiment, the shell 110 is further provided with a blowdown hole, and the blowdown hole penetrates through the bottom of the filter space 111. Specifically, the blowdown hole penetrates through the bottom wall 113, so as to discharge the substances in the filter space 111 as much as possible.
[0049] In one embodiment, the rotary drum type vacuum filter further comprises a liquid storage tank 140, and the liquid storage tank 140 also communicates with the inside of the rotary drum, for example, through a pipeline. At the same time, the pipelines between the liquid storage tank 140 and the rotary drum and between the liquid storage tank 140 and the rotary drum are provided with control valves, so as to control the liquid storage tank 140 and the liquid storage tank 140 to be alternately communicated with the inside of the rotary drum. The vacuum generator 120 is also connected with the liquid storage tank 140. In this way, when the filter cake is washed, the liquid storage tank 140 and the inside of the rotary drum can be connected, so as to input the washed liquid into the liquid storage tank 140.
[0050] In one embodiment, the recovery device further comprises an air induction fan, and the air induction fan is connected with the shell 110 of the rotary drum type vacuum filter and is used to guide the gas in the inner cavity to be discharged. It should be explained that when the fluorosilicic acid solution is used for filtration, toxic gas will be generated. The shell 110 can be provided as a sealed structure, and then the toxic gas in the inner cavity is discharged to a preset station for treatment through the air induction fan, so as to avoid the leakage of toxic gas.
[0051] On the other hand, this application also discloses a hydrogen fluoride preparation system, which includes the silicon tetrafluoride recovery device in the above embodiments. The recovery device can absorb and reuse the escaped silicon tetrafluoride gas during the hydrogen fluoride preparation process, eliminating the need for waste gas treatment equipment, thereby improving the conversion rate of hydrogen fluoride and reducing costs.
[0052] In summary, the silicon tetrafluoride recovery device and hydrogen fluoride preparation system provided in this application have at least the following advantages:
[0053] 1. In the rotary drum vacuum filter, the liquid inlet 112 is located at the bottom of the filtration space 111. When the liquid is input, it can agitate the liquid in the filtration space 111. There is no need to set up a stirring structure, which simplifies the structure and improves the stability and safety of the equipment operation.
[0054] 2. The size of the filtration space 111 gradually increases from bottom to top, while the liquid inlet 112 is located at the bottom of the bottom side wall 114, which improves the stirring effect of the input liquid and ensures that the silica solid is in a suspended state.
[0055] 3. When filtering fluorosilicic acid solution, the filter cake is first dried in the first drying zone and then washed in the washing zone, which can effectively remove the acidic substances remaining on the filter cake.
[0056] 4. An exhaust fan is installed to discharge toxic gases from the inner cavity to a preset work position, preventing toxic gas leakage and improving safety.
[0057] Although embodiments of this application have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of this application, the scope of which is defined by the appended claims and their equivalents.
Claims
1. A device for recycling silicon tetrafluoride, characterized in that, include: An input mechanism for introducing gas containing silicon tetrafluoride; An absorption mechanism, connected to the input mechanism, is used to absorb the silicon tetrafluoride and form a fluorosilicic acid solution containing silicon dioxide; Rotary drum vacuum filters include: The housing has an inner cavity, and a filter space is provided at the bottom of the inner cavity; A rotating drum is rotatably disposed within the inner cavity; The filter space has a liquid inlet at the bottom, and the absorption mechanism is connected to the liquid inlet to input a fluorosilicic acid solution containing silicon dioxide into the filter space. The bottom of the drum is immersed in the fluorosilicic acid solution.
2. The device for recovering silicon tetrafluoride according to claim 1, characterized in that, The inner cavity includes a filtration zone, a cleaning zone, and a feeding zone arranged along the rotation direction of the drum, and the filtration space is located at the bottom of the filtration zone; The drum is located outside the filtration zone and can form a filter cake. During the rotation of the drum, the filter cake on the outside of the drum can pass through the washing zone and the feeding zone, and the filter cake can be separated from the drum in the feeding zone. The rotary drum vacuum filter also includes a cleaning component, which is disposed in the cleaning zone and is used to clean the filter cake passing through the cleaning zone.
3. The device for recovering silicon tetrafluoride according to claim 2, characterized in that, The inner cavity further includes a first drying zone and a second drying zone, and the filtration zone, the first drying zone, the cleaning zone, the second drying zone and the feeding zone are arranged along the rotation direction of the drum.
4. The silicon tetrafluoride recovery device according to claim 3, characterized in that, The inner cavity also includes a backflushing zone, which is located between the second drying zone and the feeding zone; The rotary drum vacuum filter also includes a backflushing element, which is at least partially disposed in the backflushing zone and extends into the rotary drum. The backflushing element is used to blow air toward the inner side of the portion of the rotary drum located in the backflushing zone.
5. The device for recovering silicon tetrafluoride according to claim 2, characterized in that, The rotary drum vacuum filter also includes a scraper, which is disposed in the feeding area and is used to scrape the filter cake passing through the feeding area away from the rotary drum.
6. The device for recovering silicon tetrafluoride according to claim 1, characterized in that, The filtration space includes a bottom wall and bottom side walls connected to opposite sides of the bottom wall, the two bottom side walls extending away from each other, and the liquid inlet is located at the bottom of the bottom side walls.
7. The silicon tetrafluoride recovery apparatus according to claim 6, characterized in that, Each of the bottom sidewalls has a liquid inlet at its bottom.
8. The device for recovering silicon tetrafluoride according to claim 1, characterized in that, It also includes a raw liquid tank and a vacuum generator, wherein the raw liquid tank is connected to the interior of the rotating drum, and the vacuum generator is connected to the raw liquid tank.
9. The device for recovering silicon tetrafluoride according to claim 8, characterized in that, It also includes an induced draft fan, which is connected to the housing.
10. A hydrogen fluoride preparation system, characterized in that, Includes the silicon tetrafluoride recycling apparatus according to any one of claims 1-9.