CN217646421U - Cracking reactor - Google Patents

Abstract

The application discloses a cracking reactor, which relates to the technical field of fluidized beds, wherein a reactor shell comprises an outer shell and an inner shell, and the inner shell is provided with an inner cavity; the inner cavity comprises a feeding section, an expanding section and a reaction section, wherein the feeding section is provided with a seed crystal feeding pipe, the reaction section is provided with a gas distribution device, and the gas distribution device comprises a fluidized gas feeding pipe, a reaction gas feeding pipe and a polycrystalline silicon separation hole. The method has the following specific beneficial effects: 1. the safety of the reaction process is enhanced and the dependence on materials is reduced by the double-layer structure design of the inner shell and the outer shell; 2. the bulk bubbles are crushed by the expanding section, a crushing piece is omitted, and the influence of silicon particle sintering on the reaction sectional area of the inner cavity is reduced; 3. through the arrangement of the fluidization gas feeding pipe, the reaction gas feeding pipe and the protection gas feeding pipe which are arranged in a staggered manner, the possibility of large bubbles is reduced, and the occurrence of slugging is reduced; 4. through cooling gas cooling, the sintering of silicon particles at the top of the inner cavity is reduced, and the flow rate of gas at the top is increased, so that dust can be brought out quickly.

Description

Cracking reactor

Technical Field

The present application relates to the technical field of fluidized beds, and more particularly, it relates to a cracking reactor.

Background

Polycrystalline silicon is an extremely important excellent semiconductor material and is widely used for manufacturing products such as semiconductor devices, solar cells and the like. Due to the rapid consumption of ore resources and the environmental protection requirement of low carbon, green renewable energy is being developed more and more globally. Solar energy has the characteristics of cleanness, safety, abundant resources and the like, has the most development potential in renewable resources, and a silicon-based solar cell is one of the most ideal solar cells, so that the market demand for high-purity polycrystalline silicon is continuously increased along with the vigorous development of the industry.

At present, the production technology of polycrystalline silicon mainly comprises an improved Siemens method and a silane method. The siemens process produces columnar polysilicon by vapor deposition, and the silane process is a process in which silane is introduced into a fluidized bed using polysilicon seed crystals as fluidized particles to crack and deposit silane on the seed crystals to obtain polysilicon. The improved Siemens method and the silane method can produce electronic grade polycrystalline silicon and can also produce solar grade polycrystalline silicon.

The silane cracking reactor is a core device for producing polycrystalline silicon by a silane method, silane or silicon-containing gas is heated and decomposed by a heater arranged outside in the silane cracking reactor, and silicon generated by decomposition is deposited on fluidized seed crystals, so that qualified polycrystalline silicon grown is harvested. The obtained polycrystalline silicon can be directly used for downstream Czochralski single crystal without crushing and cleaning, so that the production cost is greatly reduced. Due to the easy flowability of the polycrystalline silicon, the full-automatic control of the downstream crystal pulling process can be assisted, and the working efficiency is further improved.

However, the silane cracking reactor belongs to a gas-solid two-phase reaction, the particle size is large, fluidized gas and silane or silicon-containing gas can form clustered bubbles after entering the reactor through a nozzle, the clustered bubbles can be combined with each other due to the combined action of internal pressure and gas in the rising process in the reactor, the bubbles can be continuously combined and gradually grow up due to the unreasonable arrangement of a distributor or the nozzle until the diameters of the bubbles are close to the diameters of the inner walls of the reactor, the phenomenon of slugging in the reactor is formed, the stable operation of the reactor is influenced, and even the production is interrupted. Silicon granule rapid motion upwards can be smugglied secretly to big bubble, breaks at the reactor top, and partial silicon granule can be along with tail gas entering tail gas processing system, causes the material loss in tail gas pipeline jam and the reactor, reduces the productivity.

SUMMERY OF THE UTILITY MODEL

To reduce the occurrence of slugging, the present application provides a cleavage reactor.

The application provides a cracking reactor, adopts following technical scheme:

a cracking reactor comprises a reactor shell, wherein the reactor shell comprises an outer shell and an inner shell, and an inner cavity is formed in the inner shell;

the inner cavity comprises a feeding section, an expanding section and a reaction section which are sequentially arranged from top to bottom;

the feeding section is provided with a seed crystal feeding pipe;

a heating device for heating the reaction section is arranged between the outer shell and the inner shell, a gas distribution device is arranged below the reaction section, the gas distribution device comprises a bearing main body, and a fluidized gas feeding pipe and a reaction gas feeding pipe which are arranged on the bearing main body, and polycrystalline silicon sorting holes for leading out polycrystalline silicon are formed in the bearing main body;

the cross-sectional area of the expanding section in the horizontal direction gradually increases towards the direction far away from the reaction section.

Through above-mentioned technical scheme, set up and enlarge the section, the in-process of actual production polycrystalline silicon, the globoid bubble that fluidization gas or reaction gas produced, can be by lower supreme motion, when reaching and enlarging the section, because the cross sectional area who enlarges the section enlarges gradually, and then the globoid bubble is in the motion-up in-process of enlarging the section, the globoid bubble can constantly enlarge, along with the globoid bubble enlarges, the internal and external pressure differential of globoid bubble can be bigger and bigger, and then can make the globoid bubble broken, reduce and enlarge the inside gas flow rate of section, reduce the soaring phenomenon of intracavity and take place.

Optionally, the gas distribution device further comprises a shielding gas feeding pipe, and the outer ring of the reaction gas feeding pipe is coaxially sleeved with the shielding gas feeding pipe.

Through above-mentioned technical scheme, set up the protection gas inlet pipe, let in the protection gas through the protection gas inlet pipe, the outer end of parcel reaction gas inlet pipe prevents that the reaction gas from being heated in the reaction gas inlet pipe and decomposing and forming silica flour, reduces the possibility that silica flour blockked up the reaction gas inlet pipe, improves whole moving stability.

Optionally, reaction gas inlet pipe and protection gas inlet pipe all are vertical setting, the top height of reaction gas inlet pipe is higher than the top height of protection gas inlet pipe.

Through above-mentioned technical scheme, the top that sets up the reaction gas inlet pipe highly is higher than the top height of protection gas inlet pipe, can effectively reduce the condition that the bulk bubble that the reaction gas inlet pipe produced and the bulk bubble that the protection gas inlet pipe produced merge into the big bubble at the in-process that rises, reduces the possibility that the phenomenon appears that soaks in the inner chamber.

Optionally, the fluidized gas feeding pipe and the reaction gas feeding pipe are both vertically arranged, and the height of the top end of the fluidized gas feeding pipe is not consistent with that of the top end of the reaction gas feeding pipe.

Through above-mentioned technical scheme, the top height that sets up the fluidization gas inlet pipe is highly inconsistent with the top of reaction gas inlet pipe, reduces the condition that the reunion bubble that fluidization gas inlet pipe produced and the reunion bubble that reaction gas inlet pipe produced merge into the big bubble at the in-process that rises, reduces the possibility that the phenomenon appears that soaks in the inner chamber.

Optionally, the inner shell includes an inner shell and an inner liner, the inner liner is disposed inside the inner shell, the inner cavity is formed inside the inner liner, the inner liner is made of a high-temperature-resistant non-metallic material, and the inner shell is made of a heat-conducting metal material.

Through above-mentioned technical scheme, it includes inner shell and inside lining to set up the interior casing, and sets up the inside lining and be high temperature resistant non-metallic material, and then can reduce reaction gas and seed crystal in the contact of reaction in-process with the metal, reduces metallic impurity's pollution.

Optionally, an expansion joint device is arranged at the top of the inner shell, and the expansion joint device includes a protective shell, a first corrugated expansion joint, a second corrugated expansion joint, a third corrugated expansion joint, a fourth corrugated expansion joint, a first connecting piece and a second connecting piece;

the protective shell is fixed at the top of the feeding section, the second corrugated expansion joint is sleeved on the outer ring of the first corrugated expansion joint, the upper end of the second corrugated expansion joint and the upper end of the first corrugated expansion joint are respectively and fixedly connected with the protective shell, the lower end of the second corrugated expansion joint and the lower end of the first corrugated expansion joint are respectively connected with the upper end of the first connecting piece, and the lower end of the first connecting piece is connected with the upper end of the lining;

the third ripple expansion joint sets up in the outer lane of second ripple expansion joint, the outer lane of third ripple expansion joint is located to fourth ripple expansion joint cover, the upper end of third ripple expansion joint and the upper end of fourth ripple expansion joint equally divide do not with protective housing fixed connection, the second connecting piece is located the lower extreme of first connecting piece, the lower extreme of third ripple expansion joint and the lower extreme of fourth ripple expansion joint equally divide do not be connected with second connecting piece upper end, the lower extreme of second connecting piece is connected with the upper end of inner shell.

Through above-mentioned technical scheme, set up the expansion joint device, inside lining and inner shell are heated the inflation back, and first ripple expansion joint and second ripple expansion joint can carry out free flexible according to the inflation volume of inside lining to this offsets thermal stress, and third ripple expansion joint and fourth ripple expansion joint can carry out free flexible according to the inflation volume of inner shell, offset thermal stress with this.

Optionally, the protective shell is provided with a first cooling air inlet, a first cooling air outlet, a second cooling air inlet and a second cooling air outlet;

the lower end of the first cooling gas inlet and the lower end of the first cooling gas outlet are respectively communicated above a gap between the first corrugated expansion joint and the second corrugated expansion joint;

and the lower end of the second cooling gas inlet and the lower end of the second cooling gas outlet are respectively communicated above a gap between the third corrugated expansion joint and the fourth corrugated expansion joint.

Through the technical scheme, the first cooling gas inlet, the first cooling gas outlet, the second cooling gas inlet and the second cooling gas outlet are arranged, cooling gas can be introduced into the first cooling gas inlet and can flow in a gap between the first corrugated expansion joint and the second corrugated expansion joint by matching with the first cooling gas outlet, so that the first corrugated expansion joint and the second corrugated expansion joint are cooled, the stability of the first corrugated expansion joint and the second corrugated expansion joint in a high-temperature state is improved, and the possibility of failure is reduced;

the second cooling gas import can let in the cooling gas, and the cooperation second cooling gas export for the cooling gas can flow in the gap between third ripple expansion joint and the fourth ripple expansion joint, for third ripple expansion joint and fourth ripple expansion joint provide the cooling, improves the stability of third ripple expansion joint and fourth ripple expansion joint under high temperature state, reduces the possibility of inefficacy.

Optionally, a heat insulation layer is arranged between the inner shell and the outer shell.

Through above-mentioned technical scheme, set up the insulating layer, reduce the heat transfer between interior casing and the shell body for the heat that heating device provided can be better act on interior casing, improve the reaction effect of reaction gas and seed crystal.

Optionally, the top of the fluidization gas feeding pipe is provided with a fluidization gas nozzle, the top of the reaction gas feeding pipe is provided with a reaction gas nozzle, and the top of the shielding gas feeding pipe is provided with a shielding gas nozzle.

Through above-mentioned technical scheme, set up fluidization gas shower nozzle, reaction gas shower nozzle and protective gas shower nozzle, spout fluidization gas, reaction gas and protective gas respectively, through the form that sprays, reduce the reaction gas and be heated and decompose into silicon and the direct deposition in the inner chamber cavity bottom of possibility, improve the use of interior casing durable.

Optionally, a cooling gas feed pipe is arranged at the top of the feed section, and the gas outlet end of the cooling gas feed pipe is arranged towards the expansion section.

Through above-mentioned technical scheme, set up the cooling gas inlet pipe, let in the cooling gas from the feeding section top, dilute the cooling to the high-temperature gas at feeding section top, increase the top gas flow rate, take away the tiny dust that the schizolysis produced fast, further reduce the sintering of the tiny miropowder in reactor top and reunite the risk, improve the use of interior casing durable.

In summary, the present application includes at least one of the following beneficial technical effects:

(1) By arranging the expansion section, when the bulk bubbles generated by the fluidized gas or the reaction gas move from bottom to top, when the bulk bubbles reach the expansion section, the cross-sectional area of the expansion section is gradually expanded, and the bulk bubbles are continuously expanded, so that the internal and external pressure difference of the bulk bubbles is inconsistent, the bulk bubbles can be crushed, the gas flow rate in the expansion section is reduced, and the occurrence of the slugging phenomenon in the inner cavity is reduced;

(2) The heat transfer between the inner shell and the outer shell is reduced by arranging the heat insulation layer, so that the heat provided by the heating device can better act on the inner shell, and the reaction effect of the reaction gas and the seed crystal is improved;

(3) The fluidized gas nozzle, the reaction gas nozzle and the protective gas nozzle are arranged to respectively spray the fluidized gas, the reaction gas and the protective gas, and the possibility that the reaction gas is heated and decomposed into silicon and directly deposited at the bottom of the inner cavity is reduced by the spraying form, so that the service durability of the inner shell is improved;

(4) By arranging the cooling gas feeding pipe, cooling gas enters the inner cavity through the cooling gas feeding pipe, high-temperature gas at the top of the inner cavity is diluted and cooled, the flow velocity of gas at the top is increased, fine dust generated by cracking is brought out quickly, the risk of sintering and agglomeration of fine micro powder at the top of the inner cavity is further reduced, and the blockage of a tail gas discharging pipe is also avoided;

(5) Through the double-layer structure design of the inner shell and the outer shell, on one hand, the safety of the reaction process is enhanced, and on the other hand, the dependence on materials is also reduced.

Drawings

Fig. 1 is a schematic cross-sectional view of the overall structure of the first embodiment.

Fig. 2 is a schematic structural diagram of a gas distribution apparatus according to a first embodiment.

Fig. 3 is a schematic structural view of an expansion joint device according to the first embodiment.

Fig. 4 is a schematic sectional view of the overall structure of the second embodiment.

Reference numerals: 1. a reactor shell; 101. an inner housing; 1011. an inner shell; 1012. a liner; 102. an outer housing; 2. a heating device; 3. a thermal insulation layer; 4. an inner cavity; 41. a feeding section; 42. an expansion section; 43. a reaction section; 431. a first reaction section; 432. a second reaction section; 5. a seed crystal feeding pipe; 6. a cooling gas feed pipe; 7. a tail gas discharge pipe; 8. a fluidizing gas feed pipe; 9. a reaction gas feeding pipe; 10. a polysilicon sorting hole; 11. a polysilicon harvesting tube; 12. a shielding gas feed pipe; 13. a reaction gas nozzle; 14. a shielding gas spray head; 15. a fluidizing gas spray head; 16. an expansion joint device; 161. a protective shell; 162. a first bellows expansion joint; 163. a second bellows expansion joint; 164. a third corrugated expansion joint; 165. a fourth bellows expansion joint; 166. a first connecting member; 167. a second connecting member; 17. a first cooling gas inlet; 18. a first cooling gas outlet; 19. a second cooling gas inlet; 20. a second cooling gas outlet; 21. a load bearing body; 22. annular guide table.

Detailed Description

The present application is described in further detail below with reference to the attached drawings.

The embodiment of the application discloses a cracking reactor.

Example one

Referring to fig. 1, a reactor shell 1 is included, and the reactor shell 1 includes an inner shell 101 and an outer shell 102.

Referring to fig. 1, a heating device 2 is installed between an outer case 102 and an inner case 101, and the heating device 2 is induction heating. A heat insulation layer 3 is further arranged between the outer shell 102 and the inner shell 101, and the heat insulation layer 3 is attached to the inner wall of the outer shell 102. The heat insulation layer 3 is made of rock wool. Through setting up insulating layer 3, reduce the heat of heating device 2 towards outer casing 102 transmission for the heat that heating device 2 produced concentrates on interior casing 101 more, improves the heating effect to interior casing 101.

Alternatively, the heating device 2 may also be radiant heating. The material of the heat insulation layer 3 can also be asbestos.

Referring to fig. 1, the double-layer structure design of the reactor shell 1 enhances safety on one hand and is more convenient to overhaul on the other hand. In the actual use process, the pressure between the inner shell 101 and the outer shell 102 is adjusted through a pressure control valve, so that the stability and the safety of the reaction process are further guaranteed.

Referring to fig. 1, the inner housing 101 includes an inner housing 1011 and an inner liner 1012, the inner liner 1012 being fixed to the inside of the inner housing 1011. In one embodiment, the material of the liner 1012 may be a graphite silicon carbide coating material. The material of the inner housing 1011 may be alloy steel. The material of the outer housing 102 may be alloy steel.

In another embodiment, the material of the liner 1012 may also be carbon-carbon composite silicon coating or silicon carbide or silicon nitride. The specific materials of the inner liner 1012, the inner shell 1011 and the outer shell 102 may be adjusted according to actual production requirements, and the embodiment is not limited in detail.

Referring to fig. 1, the liner 1012 has an interior cavity 4 formed therein. The inner cavity 4 comprises a feeding section 41, an expanding section 42 and a reaction section 43 which are arranged from top to bottom in sequence. The cross-sections of the feed section 41, the expansion section 42, and the reaction section 43 in the horizontal direction are circular surfaces. The diameter of the feed section 41 is larger than that of the reaction section 43, and the diameter of the expansion section 42 gradually increases from the reaction section 43 to the feed section 41.

Referring to fig. 1, the reaction section 43 is composed of a first reaction section 431 and a second reaction section 432, the second reaction section 432 is located between the expansion section 42 and the first reaction section 431, and the heating device 2 is located at an outer ring of the first reaction section 431 for heating the first reaction section 431.

Referring to fig. 1, a seed crystal feeding pipe 5, a cooling gas feeding pipe 6, and a tail gas discharging pipe 7 are installed at the top of the feeding section 41. Seed crystal filling tube 5, cooling gas inlet pipe 6 and tail gas discharging pipe 7 all are vertical setting. The upper end of seed crystal filling tube 5 is the feed inlet, and the lower extreme is the discharge gate, and the upper end of seed crystal filling tube 5 runs through reactor shell 1 and stretches out to the outside, and the lower extreme orientation of seed crystal filling tube 5 enlarges the section 42 setting, and seed crystal filling tube 5 is used for leading-in seed crystal in to feed section 41. The upper end of the cooling gas feed pipe 6 is a gas inlet end, the lower end of the cooling gas feed pipe 6 is a gas outlet end, the upper end of the cooling gas feed pipe 6 penetrates through the reactor shell 1 and extends out to the outside, the lower end of the cooling gas feed pipe 6 is arranged towards the expansion section 42, and the cooling gas feed pipe 6 is used for leading cooling gas into the feed section 41. The upper end of the tail gas discharging pipe 7 is a discharging port, and the upper end of the tail gas discharging pipe 7 penetrates through the reactor shell 1 and extends out of the reactor shell.

Referring to fig. 1 and 2, a gas distribution device is disposed below the reaction section 43, and includes a bearing body 21, a fluidizing gas feed pipe 8, a reaction gas feed pipe 9, a polysilicon sorting hole 10, a polysilicon harvest pipe 11, and a shielding gas feed pipe 12. The fluidization gas feed pipe 8, the reaction gas feed pipe 9 and the shielding gas feed pipe 12 are all vertically arranged.

Referring to fig. 1 and 2, the carrier body 21 is installed inside the reaction section 43, the carrier body 21 is disposed near the bottom end of the reaction section 43, and the fluidizing gas feeding pipe 8, the reaction gas feeding pipe 9, the polysilicon harvesting pipe 11, and the shielding gas feeding pipe 12 are all installed on the carrier body 21.

Referring to fig. 1 and 2, the upper end of the reaction gas feeding pipe 9 is a gas outlet, the gas outlet of the reaction gas feeding pipe 9 is located above the bearing main body 21, a reaction gas nozzle 13 is installed at the gas outlet of the reaction gas feeding pipe 9, the lower end of the reaction gas is a gas inlet, the lower end of the reaction gas feeding pipe 9 penetrates through the bottom of the outer shell 102, the axis of the reaction gas feeding pipe 9 coincides with the axis of the reaction section 43, the reaction gas feeding pipe 9 is used for introducing the reaction gas into the reaction section 43, and the reaction gas is silane gas.

Alternatively, the reaction gas may be a silicon-containing gas such as disilane gas or dichlorosilane gas.

Referring to fig. 1 and 2, the upper end of the shielding gas feeding pipe 12 is a gas outlet, the gas outlet of the shielding gas feeding pipe 12 is located above the bearing body 21, the shielding gas nozzle 14 is installed at the gas outlet of the shielding gas feeding pipe 12, the lower end of the shielding gas feeding pipe 12 is a gas inlet, and the lower end of the shielding gas feeding pipe 12 penetrates through the bottom of the reactor shell 1. The protective gas feeding pipe 12 is coaxially sleeved on the outer ring of the reaction gas feeding pipe 9, the protective gas feeding pipe 12 is used for leading in protective gas, and the protective gas is hydrogen. The upper end of the shielding gas feed pipe 12 is lower than the upper end of the reaction gas feed pipe 9, and the height difference between the upper end of the shielding gas feed pipe 12 and the upper end of the reaction gas feed pipe 9 is 100-300mm.

Referring to fig. 1 and 2, the upper end of the fluidization gas feeding pipe 8 is a gas outlet, the gas outlet of the fluidization gas feeding pipe 8 is located above the bearing body 21, the gas outlet of the fluidization gas feeding pipe 8 is provided with a fluidization gas nozzle 15, the lower end of the fluidization gas feeding pipe 8 is a gas inlet, and the lower end of the fluidization gas feeding pipe 8 penetrates through the bottom of the reactor shell 1. The fluidizing gas feeding pipe 8 is used for guiding fluidizing gas, which is hydrogen, to the reaction section 43. The fluidization gas feed pipe 8 is provided with a plurality of fluidization gas feed pipes 8 which are circumferentially and uniformly distributed on the periphery of the shielding gas feed pipe 12. The height of the upper end of the fluidizing gas feeding pipe 8 is lower than that of the upper end of the reaction gas feeding pipe 9, and the height difference between the upper end of the fluidizing gas feeding pipe 8 and the height of the reaction gas feeding pipe 9 is 100-300mm.

Referring to fig. 1 and 2, a plurality of polysilicon sorting holes 10 are provided, the plurality of polysilicon sorting holes 10 are formed in the bearing body 21, the axis of each polysilicon sorting hole 10 is arranged along the vertical direction, and the diameter of each polysilicon sorting hole 10 is 30-50mm. The polycrystalline silicon harvesting pipes 11 are provided with a plurality of polycrystalline silicon harvesting pipes, the polycrystalline silicon harvesting pipes 11 are connected to the lower ends of the polycrystalline silicon sorting holes 10 in a one-to-one correspondence mode, and one ends, far away from the polycrystalline silicon sorting holes 10, of the polycrystalline silicon harvesting pipes 11 penetrate through the bottom of the reactor shell 1 downwards.

Referring to fig. 1 and 2, in the actual process of preparing polycrystalline silicon, the heating device 2 heats the inner cavity 4, the temperature in the inner cavity 4 is maintained at 400-900 ℃, and the working pressure of the inner cavity 4 is maintained at 0-1.5Mpa. The seed crystal is continuously led into the seed crystal through the seed crystal feeding pipe 5, the fluidizing gas is continuously led into the fluidizing gas feeding pipe 8, the fluidizing gas provides power for fluidizing the seed crystal, the reaction gas feeding pipe 9 continuously leads in the reaction gas, silicon generated by thermal decomposition of the reaction gas is deposited on the seed crystal, the seed crystal gradually grows into polycrystalline silicon, the typical grain size of the qualified polycrystalline silicon is 1-3mm, the qualified polycrystalline silicon falls on the polycrystalline silicon sorting hole 10 and is obtained by the polycrystalline silicon harvesting pipe 11, and the polycrystalline silicon which is not grown to be qualified can be reversely blown to the inner cavity 4 by reverse airflow in the polycrystalline silicon harvesting pipe 11 and is continuously deposited. In the process of generating polysilicon through reaction, the protective gas introduced into the protective gas feeding pipe 12 can wrap the reaction gas feeding pipe 9, so that the possibility of thermal decomposition of the reaction gas in the reaction gas feeding pipe 9 is reduced, the possibility of silica powder blockage in the reaction gas feeding pipe 9 is reduced, and the stability of the whole operation is improved. Due to the existence of the fluidizing gas nozzles 15, the shielding gas nozzles 14 and the reaction gas nozzles 13, the gas flow is continuously sprayed upwards, and the deposition of silicon on the bottom of the reaction section 43 is reduced.

Referring to fig. 1 and 2, since the heights of the upper ends of the fluidizing gas feeding pipe 8 and the shielding gas feeding pipe 12 are different from the height of the upper end of the reaction gas feeding pipe 9, the agglomerated bubbles generated by the shielding gas and the fluidizing gas are less likely to contact the agglomerated bubbles generated by the reaction gas, and the generation of large agglomerated bubbles can be reduced. And because the globoid bubble rises to and enlarges the section 42 after, the diameter of enlarging the section 42 is constantly increased, can make the volume of globoid bubble bigger and bigger, lead to the internal and external pressure difference of globoid bubble bigger and bigger, and then make the globoid bubble break for gaseous velocity of flow reduces, and then the emergence of effectual reduction spewing phenomenon, the effectual risk that has reduced seed crystal, polycrystalline silicon etc. and has been taken out inner chamber 4.

Referring to fig. 1 and 2, because the cooling gas inlet pipe 6 that the feed section 41 top set up constantly sprays into the cooling gas toward feed section 41, the cooling gas can dilute the cooling to the high temperature gas at feed section 41 top, increases the gaseous relative velocity of flow in top, and the quick tiny dust that produces with the schizolysis takes out, reduces the possibility of tiny dust in the sintering of feed section 41 top, reduces the possibility that the tail gas outlet blockked up, improves whole moving stability.

Referring to fig. 1 and 2, the gas distribution apparatus further includes an annular guide table 22, the annular guide table 22 is fixed to the upper end of the bearing body 21, the inner diameter of the annular guide table 22 is gradually reduced from top to bottom, and the inner ring of the lower end of the annular guide table 22 is located outside the plurality of polysilicon sorting holes 10. The ring-shaped material guide table 22 can guide the generated polycrystalline silicon to the polycrystalline silicon sorting holes 10, and the polycrystalline silicon guiding efficiency is improved.

Referring to fig. 1 and 3, an expansion joint device 16 is fixed to the top of an inner casing 101. The expansion joint device 16 includes a protective shell 161, a first bellows expansion joint 162, a second bellows expansion joint 163, a third bellows expansion joint 164, a fourth bellows expansion joint 165, a first connector 166, and a second connector 167.

Referring to fig. 1 and 3, the protective case 161 is positioned on the top of the inner case 101, and the upper end of the protective case 161 is fixedly connected to the upper end of the inner wall of the outer case 102. The axis of the first corrugated expansion joint 162 and the axis of the second corrugated expansion joint 163 are both arranged along the vertical direction, the outer ring of the first corrugated expansion joint 162 is coaxially sleeved on the second corrugated expansion joint 163, and the upper end of the first corrugated expansion joint 162 and the upper end of the second corrugated expansion joint 163 are fixedly connected with the protective shell 161 respectively. The first connecting member 166 is a connecting flange, and the first connecting member 166 is located at the lower ends of the first bellows expansion joint 162 and the second bellows expansion joint 163. The lower end of the first bellows expansion joint 162 and the lower end of the second bellows expansion joint 163 are coaxially fixed to the upper end of the first connecting member 166, respectively. The lower end of the first connector 166 is coaxially secured to the upper end of the liner 1012.

Referring to fig. 1 and 3, the axis of the third corrugated expansion joint 164 and the axis of the fourth corrugated expansion joint 165 are both disposed along the vertical direction, the third corrugated expansion joint 164 is coaxially disposed on the outer ring of the second corrugated expansion joint 163, and the fourth corrugated expansion joint 165 is coaxially sleeved on the outer ring of the third corrugated expansion joint 164. The upper end of the third bellows expansion joint 164 and the upper end of the fourth bellows expansion joint 165 are both fixedly connected to the protective shell 161. The second connector 167 is a connection flange, and the second connector 167 is located at the lower end of the first connector 166. The lower end of the third corrugated expansion joint 164 and the lower end of the fourth corrugated expansion joint 165 are coaxially and fixedly connected with the upper end of the second connecting piece 167. The lower end of the second connector 167 is coaxially and fixedly connected to the upper end of the inner housing 1011.

Referring to fig. 1 and 3, a first cooling air inlet 17, a first cooling air outlet 18, a second cooling air inlet 19 and a second cooling air outlet 20 are formed in the upper end of the protective shell 161, and the first cooling air inlet 17, the first cooling air outlet 18, the second cooling air inlet 19 and the second cooling air outlet 20 all penetrate through the upper end of the protective shell 161 downwards along the vertical direction. One end of the first cooling air inlet 17 and the lower end of the first cooling air outlet 18 are both communicated above the gap between the first bellows expansion joint 162 and the second bellows expansion joint 163, respectively. The lower end of the second cooling air inlet 19 and the lower end of the second cooling air outlet 20 are respectively communicated with the upper part of the gap between the third corrugated expansion joint 164 and the fourth corrugated expansion joint 165.

Referring to fig. 1 and 3, in actual use, the liner 1012 and the inner shell 1011 expand due to heat, the first bellows expansion joint 162 and the second bellows expansion joint 163 can freely expand and contract according to the expansion amount of the liner 1012 to offset the thermal stress of the liner 1012, and the third bellows expansion joint 164 and the fourth bellows expansion joint 165 can freely expand and contract according to the expansion amount of the inner shell 1011 to offset the thermal stress of the inner shell 1011, thereby ensuring that the liner 1012 and the inner shell 1011 can operate for a long time. The first cooling air inlet 17 can cool the first bellows expansion joint 162 and the second bellows expansion joint 163 by introducing cooling air, thereby reducing the possibility that the first bellows expansion joint 162 and the second bellows expansion joint 163 may fail at high temperatures. The second cooling air inlet 19 can introduce cooling air to cool the third corrugated expansion joint 164 and the fourth corrugated expansion joint 165, so that the possibility that the third corrugated expansion joint 164 and the fourth corrugated expansion joint 165 fail at a high temperature is reduced.

The working principle of the embodiment is as follows: the seed crystal feeding pipe 5 is led into the seed crystal, the fluidizing gas feeding pipe 8 is led in fluidizing gas, the seed crystal is kept in a fluidizing state by the fluidizing gas, and the reaction gas feeding pipe 9 is led in reaction gas to react with the seed crystal, so that polycrystalline silicon is generated in a high-temperature state; the arrangement of the expansion section 42 ensures that the rising process of the bulk bubbles is gradually broken, and the occurrence of slugging is reduced; the reaction gas feeding pipe 9, the fluidizing gas feeding pipe 8 and the protective gas feeding pipe 12 are arranged in a staggered manner, so that the mutual combination of the bulk bubbles can be reduced, and the occurrence of slugging is further reduced.

Example two

The difference from the first embodiment is that, referring to fig. 4, the bottom of the outer shell 102 is provided with a mounting opening, the bearing body 21 is fixed at the mounting opening, and the upper ends of the fluidizing gas feeding pipe 8, the reaction gas feeding pipe 9 and the shielding gas feeding pipe 12 all extend into the reaction section 43.

The above embodiments are preferred embodiments of the present application, and the protection scope of the present application is not limited by the above embodiments, so: all equivalent changes made according to the structure, shape and principle of the present application shall be covered by the protection scope of the present application.

Claims (10)

1. A cracking reactor comprising a reactor shell (1), characterized in that: the reactor shell (1) comprises an outer shell (102) and an inner shell (101), and an inner cavity (4) is arranged in the inner shell (101);

the inner cavity (4) comprises a feeding section (41), an expanding section (42) and a reaction section (43) which are sequentially arranged from top to bottom;

the feeding section (41) is provided with a seed crystal feeding pipe (5);

a heating device (2) for heating the reaction section (43) is arranged between the outer shell (102) and the inner shell (101), a gas distribution device is arranged below the reaction section (43), the gas distribution device comprises a bearing main body (21), and a fluidized gas feeding pipe (8) and a reaction gas feeding pipe (9) which are arranged on the bearing main body (21), and a polycrystalline silicon sorting hole (10) for leading out polycrystalline silicon is formed in the bearing main body (21);

the cross-sectional area of the expanding section (42) in the horizontal direction is gradually increased towards the direction far away from the reaction section (43).

2. Cracking reactor according to claim 1, characterized in that: the gas distribution device further comprises a shielding gas feeding pipe (12), and the outer ring of the reaction gas feeding pipe (9) is coaxially sleeved on the shielding gas feeding pipe (12).

3. Cracking reactor according to claim 2, characterized in that: reaction gas inlet pipe (9) and protective gas inlet pipe (12) all are vertical setting, the top height of reaction gas inlet pipe (9) is higher than the top height of protective gas inlet pipe (12).

4. Cracking reactor according to claim 1, characterized in that: the fluidized gas feeding pipe (8) and the reaction gas feeding pipe (9) are both vertically arranged, and the top height of the fluidized gas feeding pipe (8) is inconsistent with that of the reaction gas feeding pipe (9).

5. Cracking reactor according to claim 1, characterized in that: interior casing (101) include inner shell (1011) and inside lining (1012), inside lining (1012) set up in the inside of inner shell (1011), inner chamber (4) are seted up in the inside of inside lining (1012), the material of inside lining (1012) is high temperature resistant non-metallic material, the material of inner shell (1011) is heat conduction metal material.

6. Cracking reactor according to claim 5, characterized in that: the top of the inner shell (101) is provided with an expansion joint device (16), and the expansion joint device (16) comprises a protective shell (161), a first corrugated expansion joint (162), a second corrugated expansion joint (163), a third corrugated expansion joint (164), a fourth corrugated expansion joint (165), a first connecting piece (166) and a second connecting piece (167);

the protective shell (161) is fixed to the top of the feeding section (41), the second corrugated expansion joint (163) is sleeved on the outer ring of the first corrugated expansion joint (162), the upper end of the second corrugated expansion joint (163) and the upper end of the first corrugated expansion joint (162) are fixedly connected with the protective shell (161), the lower end of the second corrugated expansion joint (163) and the lower end of the first corrugated expansion joint (162) are connected to the upper end of the first connecting piece (166), and the lower end of the first connecting piece (166) is connected with the upper end of the lining (1012);

third ripple expansion joint (164) sets up in the outer lane of second ripple expansion joint (163), the outer lane of third ripple expansion joint (164) is located to fourth ripple expansion joint (165) cover, the upper end of third ripple expansion joint (164) and the upper end of fourth ripple expansion joint (165) are equallyd divide and do not be connected with protective housing (161) fixed connection, second connecting piece (167) are located the lower extreme of first connecting piece (166), the lower extreme of third ripple expansion joint (164) and the lower extreme of fourth ripple expansion joint (165) are equallyd divide and do not be connected with second connecting piece (167) upper end, the lower extreme of second connecting piece (167) is connected with the upper end of inner shell (1011).

7. Cracking reactor according to claim 6, characterized in that: a first cooling air inlet (17), a first cooling air outlet (18), a second cooling air inlet (19) and a second cooling air outlet (20) are formed in the protective shell (161);

the lower end of the first cooling air inlet (17) and the lower end of the first cooling air outlet (18) are respectively communicated above a gap between the first corrugated expansion joint (162) and the second corrugated expansion joint (163);

the lower end of the second cooling air inlet (19) and the lower end of the second cooling air outlet (20) are respectively communicated with the upper part of a gap between the third corrugated expansion joint (164) and the fourth corrugated expansion joint (165).

8. Cracking reactor according to claim 5, characterized in that: and a heat insulation layer (3) is arranged between the inner shell (101) and the outer shell (102).

9. Cracking reactor according to claim 2, characterized in that: the top of fluidization gas inlet pipe (8) is equipped with fluidization gas shower nozzle (15), the top of reaction gas inlet pipe (9) is equipped with reaction gas shower nozzle (13), the top of protection gas inlet pipe (12) is equipped with protection gas shower nozzle (14).

10. Cracking reactor according to claim 1, characterized in that: the top of feed section (41) is equipped with cooling gas inlet pipe (6), the end of giving vent to anger of cooling gas inlet pipe (6) sets up towards expanding section (42).

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