Device for preparing silicon dioxide by using chlorosilane waste gas

Abstract

The utility model relates to a device for preparing silicon dioxide by using chlorosilane waste gas, which comprises a chlorosilane spray tower, a carbon dioxide gas supply device, a silicon dioxide reactor, a filter, a precipitation device, a drying device and a grinding device, the carbon dioxide gas supply device is connected with the input end of the silicon dioxide reactor through a pipeline, the silicon dioxide reactor is used for generating silicon dioxide turbid liquid, the output end of the silicon dioxide reactor is connected with the filter, and the filter is used for filtering the silicon dioxide turbid liquid input by the silicon dioxide reactor. The precipitation device is used for obtaining silicon dioxide solids, the drying device is connected with the precipitation device and used for obtaining dried silicon dioxide solids, and the grinding device is connected with the drying device and used for grinding the dried silicon dioxide solids. According to the utility model, the generation of a large amount of industrial wastewater and waste ash is reduced, and the pollution to the environment is obviously reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of silicon dioxide preparation, in particular to a device for preparing silicon dioxide by utilizing chlorosilane waste gas. Background Art

[0002] The production of polysilicon, granular silicon, or organosilicon generates chlorosilane waste gas emissions. As production capacity continues to increase, so does the amount of chlorosilane waste gas, making its treatment crucial. Currently, the mainstream methods include alkali leaching and incineration. Incineration produces a large amount of granular waste ash, which requires treatment by a company with professional hazardous waste treatment qualifications. Alkali leaching produces a large amount of silicate waste liquid, which requires sewage treatment to meet standards before discharge, a significant expense for the factory. Utility Model Content

[0003] The purpose of the utility model is to provide a device for preparing silicon dioxide by utilizing chlorosilane waste gas, so as to solve the above-mentioned problems existing in the current treatment of chlorosilane waste gas.

[0004] In order to achieve the above purpose, the present invention adopts the following technical solutions:

[0005] A device for preparing silicon dioxide using chlorosilane waste gas comprises a chlorosilane spray tower for generating silicate waste liquid, a carbon dioxide gas supply device, a silicon dioxide reactor, a filter, a precipitator, a drying device, and a grinding device. The chlorosilane spray tower is connected to the input end of the silicon dioxide reactor via a pipeline, the carbon dioxide gas supply device is connected to the input end of the silicon dioxide reactor via a pipeline, the silicon dioxide reactor is used to generate a turbid silicon dioxide liquid, the output end of the silicon dioxide reactor is connected to the filter, the filter is used to filter the turbid silicon dioxide liquid input to the silicon dioxide reactor, the precipitator is connected to the filter to obtain silicon dioxide solids, the drying device is connected to the precipitator to obtain dry silicon dioxide solids, and the grinding device is connected to the drying device to grind the dry silicon dioxide solids.

[0006] Furthermore, the chlorosilane spray tower is connected to a silicate waste liquid delivery pump for delivering the silicate waste liquid generated by the chlorosilane spray tower to the silica reactor.

[0007] Furthermore, a first flow meter and a first regulating valve are provided on the pipeline between the chlorosilane spray tower and the silica reactor. The first flow meter is used to detect the flow of the silicate waste liquid, and the first regulating valve is used to regulate the flow of the silicate waste liquid.

[0008] Furthermore, a second flow meter and a second regulating valve are provided on the pipeline between the carbon dioxide gas supply device and the silicon dioxide reactor. The second flow meter is used to detect the flow of carbon dioxide gas, and the second regulating valve is used to regulate the flow of carbon dioxide gas.

[0009] Furthermore, a stirring device is provided in the silicon dioxide reactor.

[0010] Furthermore, the filter is also connected to an evaporation crystallization device, and the filtrate obtained by filtering the filter is passed through the evaporation crystallization device to obtain carbonate.

[0011] Beneficial effects of the utility model:

[0012] This utility model's device for producing silicon dioxide from chlorosilane waste gas effectively utilizes chlorosilane waste gas as a raw material, not only resolving the difficult problem of chlorosilane waste gas treatment but also achieving resource recycling. Furthermore, compared to traditional alkaline leaching and incineration methods, this device significantly reduces the generation of industrial wastewater and waste ash, significantly reducing environmental pollution and aligning with the principles of green chemistry and sustainable development. The device integrates a chlorosilane spray tower, a silicon dioxide reactor, a filter, a precipitation device, a drying device, and a grinding device, achieving an integrated process from waste gas treatment to silicon dioxide product production.

[0013] Furthermore, by installing a first flow meter and a second flow meter, the flow rates of the silicate waste liquid and carbon dioxide gas can be monitored and precisely controlled in real time, thereby optimizing reaction conditions. Furthermore, the stirring device installed in the silica reactor further ensures sufficient mixing of the reaction materials, improving reaction efficiency and conversion rate.

[0014] Furthermore, by connecting an evaporation crystallization device after the filter, the filtrate obtained by filtration can be further processed to obtain a carbonate product, thereby realizing the reuse of waste liquid and the creation of added value, and further improving the overall economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 The utility model is a principle block diagram of a device for preparing silicon dioxide by utilizing chlorosilane waste gas.

[0016] The names corresponding to the marks in the figure are:

[0017] 1. Chlorosilane spray tower,

[0018] 2. Carbon dioxide gas supply device,

[0019] 3. Silica reactor,

[0020] 4. Filters,

[0021] 5. Sedimentation device,

[0022] 6. Drying device,

[0023] 7. Grinding device,

[0024] 8. Silicate waste liquid delivery pump,

[0025] 9. First flow meter,

[0026] 10. The first regulating valve,

[0027] 11. Second flow meter,

[0028] 12. Second regulating valve,

[0029] 13. Stirring device,

[0030] 14. Evaporation crystallization device. DETAILED DESCRIPTION

[0031] The technical solutions in the embodiments of the present invention will be described clearly and completely below with reference to the accompanying drawings in the embodiments of the present invention.

[0032] like Figure 1 As shown, an apparatus for producing silica using chlorosilane waste gas includes a chlorosilane spray tower 1 for generating silicate waste liquid, a carbon dioxide gas supply device 2, a silica reactor 3, a filter 4, a precipitator 5, a drying device 6, and a grinding device 7. The chlorosilane spray tower 1 is connected to the input end of the silica reactor 3 via a pipeline, and the carbon dioxide gas supply device 2 is also connected to the input end of the silica reactor 3 via a pipeline. The silica reactor 3 is used to generate a turbid silica liquid, and its output end is connected to the filter 4. The filter 4 is used to filter the turbid silica liquid input by the silica reactor 3, and the filtered liquid is transported to the precipitator 5. The precipitator 5 is used to obtain silica solids and is connected to the drying device 6. The drying device 6 is used to obtain dried silica solids and is connected to the grinding device 7. The grinding device 7 is used to grind the dried silica solids to obtain a silica product of the desired particle size.

[0033] During use, chlorosilane waste gas first enters the chlorosilane spray tower 1, where it reacts with the sprayed alkali solution to produce a silicate waste liquid. This silicate waste liquid is then transported via a pipeline to the silica reactor 3. Simultaneously, carbon dioxide gas is output from the carbon dioxide gas supply device 2 and also enters the silica reactor 3. In the silica reactor 3, the silicate waste liquid reacts with the carbon dioxide gas to produce a turbid silica liquid. This turbid liquid is filtered through a filter 4 to produce silica solids and a filtrate. The silica solids enter a precipitation device 5 for precipitation and separation, and are then sent to a drying device 6 for drying. Finally, the dried silica solids enter a grinding device 7 for grinding to obtain a silica product of the desired particle size.

[0034] Among them, carbon dioxide gas reacts with silicate solution to obtain the trans form of silicon dioxide. Taking sodium silicate solution as an example:

[0035] Na2SiO3+2CO2+2H2O=H2SiO3↓+2NaHCO3

[0036]

[0037] In some embodiments, in order to conveniently transport the silicate waste liquid generated in the chlorosilane spray tower 1 to the silica reactor 3, as shown in FIG. Figure 1 As shown, the chlorosilane spray tower 1 is connected to a silicate waste liquid delivery pump 8. The silicate waste liquid delivery pump 8 can stably deliver the silicate waste liquid generated in the chlorosilane spray tower 1 to the silica reactor 3, thereby ensuring the continuity and stability of the reaction.

[0038] Furthermore, in order to accurately control the flow rate of the silicate waste liquid, as Figure 1 As shown, a first flowmeter 9 and a first regulating valve 10 are installed in the pipeline between the chlorosilane spray tower 1 and the silica reactor 3. The first flowmeter 9 is used to monitor the flow rate of the silicate waste liquid in real time, and the first regulating valve 10 is used to adjust the flow rate of the silicate waste liquid according to actual needs. This ensures a stable and controllable flow rate of the silicate waste liquid entering the silica reactor 3, thereby improving reaction efficiency and product quality.

[0039] Likewise, in order to precisely control the flow rate of carbon dioxide gas, such as Figure 1 As shown, a second flowmeter 11 and a second regulating valve 12 are installed on the pipeline between the carbon dioxide gas supply device 2 and the silica reactor 3. The second flowmeter 11 is used to monitor the flow rate of carbon dioxide gas in real time, and the second regulating valve 12 is used to adjust the flow rate of carbon dioxide gas according to actual needs. By precisely controlling the flow rate of carbon dioxide gas, reaction conditions can be further optimized, reaction efficiency, and product quality can be improved.

[0040] like Figure 1 As shown, in order to improve the reaction efficiency in the silica reactor 3, a stirring device 13 is provided in the silica reactor 3. The stirring device 13 can fully stir the silicate waste liquid and carbon dioxide gas, so that they are fully mixed and reacted, thereby improving the reaction efficiency and product quality.

[0041] In some embodiments, in order to make full use of the filtrate obtained by filtering the filter 4, as shown in FIG. Figure 1 As shown, filter 4 is also connected to an evaporation crystallization device 14. The filtrate obtained by filtration through filter 4 passes through evaporation crystallization device 14 to obtain a carbonate product. This not only effectively utilizes the chlorosilane waste gas, but also produces additional carbonate product, further improving resource utilization.

[0042] Obviously, the embodiments described are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art are within the scope of protection of the present invention.

Claims

1. A device for preparing silicon dioxide using chlorosilane waste gas, characterized in that: The invention comprises a chlorosilane spray tower (1) for generating silicate waste liquid, a carbon dioxide gas supply device (2), a silicon dioxide reactor (3), a filter (4), a precipitator (5), a drying device (6) and a grinding device (7), wherein the chlorosilane spray tower (1) is connected to the input end of the silicon dioxide reactor (3) via a pipeline, the carbon dioxide gas supply device (2) is connected to the input end of the silicon dioxide reactor (3) via a pipeline, the silicon dioxide reactor (3) is used to generate silicon dioxide turbidity, the output end of the silicon dioxide reactor (3) is connected to the filter (4), the filter (4) is used to filter the silicon dioxide turbidity inputted into the silicon dioxide reactor (3), the precipitator (5) is connected to the filter (4) for obtaining silicon dioxide solid, the drying device (6) is connected to the precipitator (5) for obtaining dried silicon dioxide solid, and the grinding device (7) is connected to the drying device (6) for grinding dried silicon dioxide solid.

2. The device for preparing silicon dioxide using chlorosilane waste gas according to claim 1, characterized in that: The chlorosilane spray tower (1) is connected to a silicate waste liquid delivery pump (8) for delivering the silicate waste liquid generated by the chlorosilane spray tower (1) to the silicon dioxide reactor (3).

3. The device for preparing silicon dioxide using chlorosilane waste gas according to claim 1, characterized in that: A first flow meter (9) and a first regulating valve (10) are provided on the pipeline between the chlorosilane spray tower (1) and the silica reactor (3); the first flow meter (9) is used to detect the flow rate of the silicate waste liquid; and the first regulating valve (10) is used to regulate the flow rate of the silicate waste liquid.

4. The device for preparing silicon dioxide using chlorosilane waste gas according to claim 1, characterized in that: A second flow meter (11) and a second regulating valve (12) are provided on the pipeline between the carbon dioxide gas supply device (2) and the silicon dioxide reactor (3); the second flow meter (11) is used to detect the flow rate of the carbon dioxide gas, and the second regulating valve (12) is used to adjust the flow rate of the carbon dioxide gas.

5. The device for preparing silicon dioxide using chlorosilane waste gas according to claim 1, characterized in that: The silicon dioxide reactor (3) is provided with a stirring device (13).

6. The device for preparing silicon dioxide using chlorosilane waste gas according to claim 1, characterized in that: The filter (4) is further connected to an evaporation crystallization device (14), and the filtrate obtained by filtering the filter (4) passes through the evaporation crystallization device (14) to obtain carbonate.

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