Novel dense phase section partition cold hydrogenation fluidized bed reactor

Abstract

The utility model discloses a novel concentrated phase section partition cold hydrogenation fluidized bed reactor, which divides a reaction area of a concentrated phase section of a fluidized bed into four small areas, can slow down the boundary layer effect in the fluidization process of the fluidized bed, and reduces the probability of abnormal phenomena such as channeling, dead bed and the like in the cold hydrogenation fluidized bed reactor. Good scattered fluidization in the fluidized bed is maintained, the reaction efficiency of the cold hydrogenation reactor is improved, and the production cost is reduced. The system operation period is prolonged and the maintenance cost is reduced. The stress concentration of the grating plate bubble breaker is relieved, and the possibility of deformation of the cold hydrogenation fluidized bed internal part bubble breaker is reduced. And the fluidized bed with larger diameter and higher capacity can be conveniently manufactured, the unit consumption of each energy source is reduced, and the manufacturing and production cost of the device is reduced.

Description

Technical Field

[0001] The utility model belongs to the field of polysilicon production, and in particular relates to a novel concentrated phase zoned cold hydrogenation fluidized bed reactor. Background Art

[0002] In the hydrogenation process for polysilicon production, the fluidized bed reactor is the core equipment. The process involves heating a mixture of silicon tetrachloride and hydrogen to a certain temperature before entering the fluidized bed from the bottom. Industrial silicon powder, mixed with a certain proportion of catalyst, is fluidized and reacts under high temperature, high pressure, and with the catalyst to produce trichlorosilane. A cyclone separator is installed at the fluidized bed outlet to separate silicon powder and catalyst from the reacted gas phase. With the advancement of cold hydrogenation technology, fluidized bed reactors now increasingly use multi-layered horizontal grid plate bubble breakers as internal components to improve reaction efficiency and reduce production costs.

[0003] With the continuous release of polysilicon production capacity, the design diameter of cold hydrogenation fluidized bed reactors has also continued to expand. This expansion of the fluidized bed reactor diameter deteriorates the fluidization effect within the fluidized bed, leading to a significant boundary layer effect and uneven gas distribution within the fluidized bed. This leads to channeling and dead bed phenomena within the fluidized bed reactor. This not only seriously affects the reaction effect, but also, due to the larger inner diameter of the fluidized bed, the diameter of the grid plate bubble breaker increases accordingly. Silicon powder accumulates in the bubble breaker within the fluidized bed reactor, causing deformation of the bubble breaker guide plate and the bubble breaker support plate ribs. This deformation of the bubble breaker makes it more likely that silicon powder accumulates rapidly at the deformed bubble breaker guide plate, exacerbating the channeling and dead bed phenomena within the fluidized bed reactor and ultimately forcing the cold hydrogenation production system to shut down for maintenance. On the one hand, reaction efficiency decreases and production costs increase; on the other hand, the unit operating cycle is shortened, increasing maintenance costs. Summary of the Invention

[0004] Purpose of the utility model: The technical problem to be solved by the utility model is to provide a concentrated phase partitioned cold hydrogenation fluidized bed reactor in response to the deficiencies of the existing technology, to alleviate the boundary layer effect during the fluidization process of the fluidized bed, to reduce the probability of abnormal phenomena such as channeling and dead bed in the cold hydrogenation fluidized bed reactor, to improve the fluidization effect in the fluidized bed, to improve the reaction efficiency of the cold hydrogenation reactor, and to reduce production costs.

[0005] In order to achieve the above purpose, the technical solution adopted by the utility model is as follows:

[0006] A novel dense phase zoned cold hydrogenation fluidized bed reactor comprises a fluidized bed, a cyclone separator and a fluidized bed bubble breaker arranged in the fluidized bed; the fluidized bed bubble breaker is a columnar cylindrical structure with more than one layer of multi-rotating guide baffles arranged inside; there are more than two fluidized bed bubble breakers, which are respectively arranged in the lower part of the fluidized bed, and each fluidized bed bubble breaker is provided with a silicon powder feeding pipe.

[0007] Furthermore, a baffle is installed on the top of the fluidized bed bubble breaker, the outer ring of the baffle is fixed to the inner wall of the fluidized bed, and the plate surface is flush with the top surface of each fluidized bed bubble breaker; a circular window corresponding to the air outlet at the top of the fluidized bed bubble breaker is reserved on the baffle.

[0008] Furthermore, a fluidized bed inlet distributor is provided at the bottom of the fluidized bed, and the fluidized bed inlet distributor is located below the fluidized bed bubble breaker.

[0009] Furthermore, a bubble breaker inlet distributor is provided at the bottom of the fluidized bed, and the bubble breaker inlet distributor is provided below the fluidized bed bubble breaker and above the fluidized bed inlet distributor.

[0010] Specifically, there are three or four fluidized bed bubble breakers, and outer walls of two adjacent fluidized bed bubble breakers are in contact with each other.

[0011] Specifically, two or more pressure gauges are arranged at different heights in each fluidized bed bubble breaker, and a differential pressure gauge is arranged between two adjacent pressure gauges.

[0012] Specifically, thermometers are provided at different heights in each fluidized bed bubble breaker.

[0013] Specifically, the installation area of ​​the fluidized bed bubble breaker is located between 1 / 12 and 5 / 12 of the height of the fluidized bed.

[0014] Specifically, the distance between the fluidized bed inlet distributor and the bubble breaker inlet distributor is 1200-1800 mm; the distance between the bubble breaker inlet distributor and the bottom of the fluidized bed bubble breaker is 500-600 mm.

[0015] Specifically, the cyclone separators are arranged in groups of two or more, and are spaced 300-500 mm apart from the top of the fluidized bed bubble breaker below. Beneficial effects

[0016] This new fluidized bed reactor mitigates the boundary layer effect during fluidization, reducing the likelihood of abnormalities such as channeling and dead bed formation within the cold hydrogenation fluidized bed reactor. It maintains good dispersed fluidization within the fluidized bed, improves the reaction efficiency of the cold hydrogenation reactor, and reduces production costs. It also extends the system's operating cycle and reduces maintenance costs. It alleviates stress concentration in the grid plate bubble breaker, reducing the likelihood of deformation of the bubble breaker within the cold hydrogenation fluidized bed. It facilitates the fabrication of larger diameter and higher production capacity fluidized beds, reduces energy consumption, and lowers manufacturing and production costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments, and the above and / or other advantages of the present invention will become more apparent.

[0018] Figure 1 It is a schematic diagram of the overall structure of the fluidized bed reactor.

[0019] Figure 2 It is a cross-sectional view of the baffle plate and the top of the fluidized bed bubble breaker in the fluidized bed reactor.

[0020] Figure 3 It is a cross-sectional view of the bottom of the fluidized bed bubble breaker in the fluidized bed reactor.

[0021] Figure 4 This is a diagram showing the locations of the pressure gauge and thermometer in the fluidized bed reactor.

[0022] Wherein, each reference numeral represents:

[0023] 1- fluidized bed; 2- cyclone separator; 3- fluidized bed bubble breaker; 4- baffle; 5- fluidized bed inlet distributor; 6- bubble breaker inlet distributor; 7- bubble breaker installation area; 8- silicon powder feeding pipe; 9- public area of ​​the external gap of the partitioned fluidized bed; 10- fluidized bed synthesis gas outlet. DETAILED DESCRIPTION

[0024] The present invention can be better understood according to the following embodiments.

[0025] The structures, proportions, sizes, etc. illustrated in the drawings of the specification are only used to match the contents disclosed in the specification for the understanding and reading of those familiar with this technology. They are not used to limit the conditions for the implementation of the utility model and therefore have no substantial technical significance. Any modification of the structure, change in the proportional relationship, or adjustment of the size should still fall within the scope of the technical content disclosed in the utility model without affecting the efficacy and purpose of the utility model. At the same time, terms such as "upper", "lower", "front", "back", and "middle" quoted in this specification are only for the convenience of description and are not used to limit the scope of the implementation of the utility model. Changes or adjustments in their relative relationships should also be considered as the scope of the implementation of the utility model without substantially changing the technical content.

[0026] like Figure 1 As shown, the dense phase zoned cold hydrogenation fluidized bed reactor of the present invention includes a fluidized bed 1, a cyclone separator 2 and a fluidized bed bubble breaker 3 arranged in the fluidized bed 1; the fluidized bed bubble breaker 3 is a columnar cylindrical structure, and is internally provided with more than one layer of multi-rotation guide baffles; there are more than two fluidized bed bubble breakers 3, which are respectively arranged at the same height in the lower part of the fluidized bed 1, and a silicon powder feeding pipe 8 is introduced into each fluidized bed bubble breaker 3.

[0027] Combine Figure 2As shown, in some embodiments, a baffle 4 is installed on the top of the fluidized bed bubble breaker 3, the outer ring of the baffle 4 is fixed to the inner wall of the fluidized bed 1, and the plate surface is flush with the top surface of each fluidized bed bubble breaker 3; a circular window corresponding to the top air outlet of the fluidized bed bubble breaker 3 is reserved on the baffle 4.

[0028] In some embodiments, a fluidized bed inlet distributor 5 is provided at the bottom of the fluidized bed 1 , and the fluidized bed inlet distributor 5 is located below the fluidized bed bubble breaker 3 .

[0029] In some embodiments, a bubble breaker inlet distributor 6 is further provided at the bottom of the fluidized bed 1 , and the bubble breaker inlet distributor 6 is arranged below the fluidized bed bubble breaker 3 and above the fluidized bed inlet distributor 5 .

[0030] In this embodiment, combined with Figure 2 and Figure 3 There are four fluidized bed bubble breakers 3, and the outer walls of two adjacent fluidized bed bubble breakers 3 are in contact with each other. The top of the fluidized bed bubble breakers 3 is divided into four cylindrical small areas by a baffle 4. The upper part of the common area 9 outside the partitioned fluidized bed is blocked by the baffle 4, and the lower part is open.

[0031] The mixed raw gas of silicon tetrachloride and hydrogen enters the fluidized bed from the bottom of the fluidized bed 1, passes through the fluidized bed reactor inlet distributor 5 and the bubble breaker inlet distributor 6, and then enters the partitioned fluidized bed bubble breaker 3 to react with silicon powder; the gas-solid mixture after the reaction enters the built-in cyclone separator 2 from the top of the partitioned fluidized bed bubble breaker 3. After dust removal, the solid particles return to the fluidized bed from the bottom of the built-in cyclone separator 2, and the gas enters the downstream through the fluidized bed synthesis gas outlet 10.

[0032] In this embodiment, a silicon powder feeding pipe 8 is provided in each of the four partitioned fluidized bed bubble breaker installation areas 7, for a total of four silicon powder feeding pipes.

[0033] Combine Figure 4 As shown, in this embodiment, three pressure gauges P1a / b / c / d, P2a / b / c / d, and P3a / b / c / d are provided at different heights in each fluidized bed bubble breaker 3, and a differential pressure gauge is provided between two adjacent pressure gauges, namely PDI001a / b / c / d and PDI002a / b / c / d, to observe the fluidization state in each area according to the temperature.

[0034] In this embodiment, four thermometers are provided at different heights in each fluidized bed bubble breaker 3, namely TI001a / b / c / d, TI002a / b / c / d, TI003a / b / c / d, and TI004a / b / c / d.

[0035] In some embodiments, the bubble breaker installation area 7 corresponding to the fluidized bed bubble breaker 3 is located between 1 / 12 and 5 / 12 of the height of the fluidized bed 1 .

[0036] In some embodiments, the fluidized bed inlet distributor 5 and the bubble breaker inlet distributor 6 are spaced 1200 mm apart; the bubble breaker inlet distributor 6 and the bottom of the fluidized bed bubble breaker 3 are spaced 600 mm apart.

[0037] In some embodiments, the cyclone separators 2 are grouped into two or more, and are spaced 500 mm apart from the top of the fluidized bed bubble breaker 3 below.

[0038] This partitioned cold hydrogenation fluidized bed reactor divides the dense phase reaction zone within the cold hydrogenation fluidized bed into four small areas, namely a / b / c / d. The reduction in the diameter of each area reduces the boundary layer effect generated during the fluidization process, reduces bias flow and silicon powder accumulation on the inner wall, and maintains a good fluidization form in the fluidized bed. The fluidized bed inlet distributor 5 connects the inlet distributors of the four bubble breaker areas and the four bubble breaker outlets as a common area. The four areas correspond to four silicon powder feeding ports. Three pressure taps are set at different heights in the four areas, namely P1a / b / c / d, P2a / b / c / d, and P3a / b / c / d. Pressure differential gauges PDI001a / b / c / d and PDI002a / b / c / d are installed to detect the bed pressure difference in different areas to adjust the silicon powder replenishment amount and observe the fluidization state at different heights of the fluidized bed. Inserted thermometers were installed in the four zones, with four temperature measurement points at different heights: TI001a / b / c / d, TI002a / b / c / d, TI003a / b / c / d, and TI004a / b / c / d. The fluidization state in each zone was observed based on the temperature. The upper connections of the four zones were sealed, and the lower connections were fixed with steel bars. After the gas filled the common area divided by the bubble breakers, it entered the reaction zone through the four bubble breaker inlet distributors. The lower sections were left open. This prevented silicon powder from accumulating in the common area divided by the bubble breakers. Furthermore, the pressure in the reaction zone and the common area of ​​the bubble breaker divisions were consistent, and no external forces were applied to the fluidized bed internals.

[0039] This utility model provides a novel concept and method for a dense phase zoned cold hydrogenation fluidized bed reactor. There are many methods and approaches to implement this technical solution. The above is only a preferred embodiment of the utility model. It should be noted that those skilled in the art may make various improvements and modifications without departing from the principles of the utility model, and such improvements and modifications should also be considered within the scope of protection of the utility model. Any components not specified in this embodiment may be implemented using existing technologies.

Claims

1. A novel dense phase zone cold hydrogenation fluidized bed reactor, characterized in that: The invention comprises a fluidized bed (1), a cyclone separator (2) and a fluidized bed foam breaker (3) arranged in the fluidized bed (1); the fluidized bed foam breaker (3) is a columnar cylindrical structure, and is provided with more than one layer of multi-rotation guide baffles inside; the fluidized bed foam breaker (3) is a plurality of fluidized bed foam breakers (3), which are respectively arranged at the lower part of the fluidized bed (1), and a silicon powder feeding pipe (8) is introduced into each fluidized bed foam breaker (3).

2. The novel dense phase zoned cold hydrogenation fluidized bed reactor according to claim 1, characterized in that: A baffle (4) is installed on the top of the fluidized bed bubble breaker (3), the outer ring of the baffle (4) is fixed to the inner wall of the fluidized bed (1), and the plate surface is flush with the top surface of each fluidized bed bubble breaker (3); a circular window corresponding to the air outlet at the top of the fluidized bed bubble breaker (3) is reserved on the baffle (4).

3. The novel dense phase zoned cold hydrogenation fluidized bed reactor according to claim 2, characterized in that: A fluidized bed inlet distributor (5) is provided at the bottom of the fluidized bed (1), and the fluidized bed inlet distributor (5) is located below the fluidized bed bubble breaker (3).

4. The novel dense phase zoned cold hydrogenation fluidized bed reactor according to claim 3, characterized in that: A bubble breaker inlet distributor (6) is further provided at the bottom of the fluidized bed (1), and the bubble breaker inlet distributor (6) is provided below the fluidized bed bubble breaker (3) and above the fluidized bed inlet distributor (5).

5. The novel dense phase zoned cold hydrogenation fluidized bed reactor according to claim 1, characterized in that: There are three or four fluidized bed bubble breakers (3), and the outer walls of two adjacent fluidized bed bubble breakers (3) are in contact with each other.

6. The novel dense phase zoned cold hydrogenation fluidized bed reactor according to claim 1, characterized in that: Two or more pressure gauges are arranged at different heights in each fluidized bed bubble breaker (3), and a differential pressure gauge is arranged between two adjacent pressure gauges.

7. The novel dense phase zoned cold hydrogenation fluidized bed reactor according to claim 1, characterized in that: Thermometers are provided at different heights in each fluidized bed bubble breaker (3).

8. The novel dense phase zoned cold hydrogenation fluidized bed reactor according to claim 1, characterized in that: The installation area of ​​the fluidized bed bubble breaker (3) is located between 1 / 12 and 5 / 12 of the height of the fluidized bed (1).

9. The novel dense phase zoned cold hydrogenation fluidized bed reactor according to claim 4, characterized in that: The distance between the fluidized bed inlet distributor (5) and the bubble breaker inlet distributor (6) is 1200-1800 mm; the distance between the bubble breaker inlet distributor (6) and the bottom of the fluidized bed bubble breaker (3) is 500-600 mm.

10. The novel dense phase zoned cold hydrogenation fluidized bed reactor according to claim 1, characterized in that: The cyclone separators (2) are arranged in groups of two or more, and are spaced 300-500 mm apart from the top of the fluidized bed bubble breaker (3) below.

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