CN205616579U

CN205616579U - Silane moving bed reactor

Info

Publication number: CN205616579U
Application number: CN201620214808.4U
Authority: CN
Inventors: 许文; 唐瑾; 卢喆宇
Original assignee: China Chengda Engineering Co Ltd
Current assignee: China Chengda Engineering Co Ltd
Priority date: 2016-03-21
Filing date: 2016-03-21
Publication date: 2016-10-05
Anticipated expiration: 2026-03-21

Abstract

The utility model discloses a silane moving bed reactor, including reactor casing and granule polycrystalline silicon filling tube, the discharging port of polycrystalline silicon filling tube is located the reactor casing, be divided into the reactor separation region on upper portion and the reactor conversion zone of lower part in the reactor casing reactor casing top do not is provided with and exports with tail gas with reactor separation region connected's hydrogen inlet reactor casing lower part is provided with reaction gas mixture import a plurality of and reactor reaction region connected, reactor casing bottom is provided with the material export. The utility model discloses a move the mode production granule polycrystalline silicon of the bed technique of piling up, its topmost characteristics divide the polycrystalline silicon granule contact decomposition reaction after the heating of polycrystalline silicon granule and reaction gas and the heating to open to go on to through manifold cycles heating, reaction back, make the polycrystalline silicon granule of little particle diameter grow up gradually, thereby obtain the grain product polycrystalline silicon product that we need.

Description

Silane moving-burden bed reactor

Technical field

This utility model belongs to technical field of polysilicon production, particularly to a kind of silane moving-burden bed reactor.

Background technology

At present, whole world polysilicon uses improved Siemens production technology and thermal decomposition of silane production technology mostly, and thermal decomposition of silane produces polycrystalline silicon technology two kinds at present, and one is CVD form, and one is fluid bed form.

Fluidization is to heat in the reactor that silane decomposes the heating of polycrysalline silcon, the silane gas of polycrysalline silcon and participation reaction is heated by it simultaneously, substantial amounts of silane gas so can be caused to decompose, produce substantial amounts of dust, although polycrysalline silcon surface after the heating also can deposit silicon, but efficiency can reduce.The problem of especially severe is, the heat transfer type of this heating is heater by the outer wall of reactor apparatus, heat passed to reactor in polycrysalline silcon is heated, also can be heated because of equipment inner wall simultaneously, and the temperature of outer wall can be higher than the temperature of polycrysalline silcon, make equipment inner wall also can deposit silicon, increase over time, the silicon of equipment inner wall is more and more thicker, the heats to polycrysalline silcon can be directly affected, finally result in the purpose that can not reach polycrysalline silcon heating, thus affect production of polysilicon；And due to fluid bed, polycrysalline silcon, by airflow function, seethes with excitement the most up and down, equipment inner wall is had the phenomenon washed away, so can produce metal and stain, affect the quality of polysilicon.

Utility model content

Goal of the invention of the present utility model is: for the problem of above-mentioned existence, it is provided that a kind of mode using moving bed accumulation technology produces the silane moving-burden bed reactor of granular polycrystalline silicon.

The technical solution of the utility model is achieved in that silane moving-burden bed reactor, it is characterized in that: include reactor shell and polysilicon charge pipe, the discharging port of described polysilicon charge pipe is positioned at reactor enclosure body, the reactor separated region on top and the reactor reaction region of bottom it is divided in described reactor enclosure body, the hydrogen inlet and offgas outlet connected with reactor separated region it is respectively arranged with on described reactor shell top, multiple reaction mixture gas import connected with reactor reaction region it is provided with in described reactor shell bottom, it is provided with material outlet bottom described reactor shell.

Silane moving-burden bed reactor described in the utility model, the reactor shell diameter that its described reactor separated region is corresponding is the twice of reactor shell diameter corresponding to reactor reaction region, and polysilicon crystal seed is deposited in reactor reaction region.

Silane moving-burden bed reactor described in the utility model, its described polysilicon charge pipe extends to inside reactor separated region, and polysilicon crystal seed is accumulated to the discharging port of polysilicon charge pipe.

Silane moving-burden bed reactor described in the utility model, it is provided with dust board in described reactor separated region.

Silane moving-burden bed reactor described in the utility model, it is lined with polysilicon films at described reactor shell inwall.

Silane moving-burden bed reactor described in the utility model, it is provided with chuck in described reactor shell periphery.

Silane moving-burden bed reactor described in the utility model, axial arranged along reactor shell of its multiple reaction mixture gas imports, the Inlet Position of multiple differing heights in formation reactor reaction region, described reaction mixture gas import is connected with reactor reaction region by nozzle.

This utility model have employed the mode of moving bed accumulation technology and produces granular polycrystalline silicon, this technology is different from the silane CVD and the mode of production of fluid bed that the whole world uses at present, its topmost feature is with the polycrysalline silcon after heating, polycrysalline silcon to be contacted decomposition reaction with the heating of reaction gas separately carry out, and by silane moving-burden bed reactor repeatedly circulating-heating, reaction after, the polycrysalline silcon making small particle is gradually grown up, thus obtains the finished particle polysilicon product that we need.

Accompanying drawing explanation

Fig. 1 is structural representation of the present utility model.

Fig. 2 is the process chart using this utility model to produce granular polycrystalline silicon.

Labelling in figure: 1 is reactor shell, 1a is reactor separated region, 1b reactor reaction region, 2 is polysilicon charge pipe, 3 is hydrogen inlet, 4 is offgas outlet, 5 is reaction mixture gas import, 6 is material outlet, 7 is dust board, 8 is polysilicon films, 9 is chuck, 10 is flow control regulator, 11 is nozzle, 12 is silane moving-burden bed reactor, 13 is valve, 14 is polycrysalline silcon high position receiving slit/pre-heater, 15 is heater, 16 is polycrysalline silcon low level receiving slit, 17 is solid material blood circulation, 18 is silane and hydrogen blender, 19 is cyclone separator, 20 is tail gas recycle, separate and blood circulation, 21 is finished product receiving slit, 22 is product handling system system.

Detailed description of the invention

Below in conjunction with the accompanying drawings, this utility model is described in detail.

In order to make the purpose of this utility model, technical scheme and advantage clearer, below in conjunction with drawings and Examples, this utility model is further elaborated.Should be appreciated that specific embodiment described herein, only in order to explain this utility model, is not used to limit this utility model.

nullAs shown in Figure 1，Silane moving-burden bed reactor，Including reactor shell 1 and polysilicon charge pipe 2，Described reactor shell material uses 310S rustless steel，The discharging port of described polysilicon charge pipe 2 is positioned at reactor shell 1，The reactor separated region 1a on top and the reactor reaction region 1b of bottom it is divided in described reactor shell 1，The hydrogen inlet 3 and offgas outlet 4 connected with reactor separated region 1a it is respectively arranged with on described reactor shell 1 top，Described reactor shell 1 bottom is provided with multiple reaction mixture gas import 5 connected with reactor reaction region 1b，Axial arranged along reactor shell 1 of multiple reaction mixture gas imports 5，The Inlet Position of multiple differing heights in formation reactor reaction region 1b，To increase reaction contact area and to be more effectively completed reaction，Described reaction mixture gas import 5 is connected with reactor reaction region 1b by nozzle 11，Make gas abundant in reactor reaction region and polysilicon seed particles surface haptoreaction，It is provided with material outlet 6 bottom described reactor shell 1.

Wherein, described reactor shell diameter corresponding for reactor separated region 1a is the twice of reactor shell diameter corresponding for reactor reaction region 1b, polysilicon crystal seed is deposited in the 1b of reactor reaction region, is provided with dust board 7 in described reactor separated region 1a.Use the design of said structure, it is simple to polysilicon crystal seed is piled up in reactor reaction region, increase the response time；Upper separation zone territory diameter is more than territory, lower reaction zone and the setting of dust board simultaneously, it is easy to tail gas escapes from piling up seed particles, allows and carries dust settling secretly and get off；Described polysilicon charge pipe 2 extends to inside reactor separated region 1a, polysilicon crystal seed is accumulated to the discharging port of polysilicon charge pipe 2, this design is to increase after reaction in tail gas abjection reactor solids surface to the distance exported, the depositing dust treatment measures carrying polysilicon dust secretly can also be set up in reaction end gas in the space of this part simultaneously, it is to avoid polysilicon dust results in blockage in outside exhaust pipe.

Do not contact with moving bed equipment metal inner surface to isolate the polycrysalline silcon participating in reaction, thus reach the purpose avoiding polycrysalline silcon by equipment metallic pollution, maintain polysilicon product purity, it is lined with polysilicon films 8 at described reactor shell 1 inwall, described reactor shell 1 periphery is provided with chuck 9, play insulation effect, at the material outlet 6 of described reactor shell 1, be provided with flow control regulator 10, it is simple to the polycrysalline silcon of control different-grain diameter flow in the reactor.

As in figure 2 it is shown, for the method using silane moving-burden bed reactor of the present utility model to produce granular polycrystalline silicon, specifically include following steps:

A), produce the beginning initial stage, close the valve 13 of silane moving-burden bed reactor 12 bottoms material outlet 6, and make polycrysalline silcon high position receiving slit/pre-heater 14 and heater 15 work.

B), in polycrysalline silcon high position receiving slit/pre-heater 14, a certain amount of granular polycrystalline silicon is loaded as crystal seed, polycrysalline silcon particle diameter after grinding is about 0.3mm, amount is about the weight of 4 times of moving-burden bed reactor conversion zone volume, as the crystal seed producing granular polycrystalline silicon, polycrysalline silcon is made to be re-fed in heater 15 heating after preheating in high-order receiving slit/pre-heater 14, polycrysalline silcon after heating flows to silane moving-burden bed reactor 12, makes the polysilicon in silane moving-burden bed reactor 12 conversion zone reach to pile up full state.

C), after first heating, open the valve 13 of silane moving-burden bed reactor 12 bottoms material outlet 6, the granular polycrystalline silicon after heating is made to fall in polycrysalline silcon low level receiving slit 16, the flow-control of this valve can determine according to the production capacity of reactor, if 500 tons/year of granular polycrystalline silicon assay devices, flow is about 12.8kg/min；Described polycrysalline silcon low level receiving slit 16 is connected formation loop structure by pipeline and solid material blood circulation 17 with polycrysalline silcon high position receiving slit/pre-heater 14, makes solid material circulate.

D), solid material is after repeatedly circulation, after the polycrysalline silcon temperature checking the polysilicon charge pipe 2 discharging near ports entering silane moving-burden bed reactor 12 reaches 850 DEG C～1000 DEG C, open silane and hydrogen blender 18 valve, spray into through silane and the mixed silane of hydrogen vaporization/blender 18 and hydrogen mixed gas in silane moving-burden bed reactor 12, this mixture temperature is about 450 DEG C, silane and hydrogen mixed gas after vaporization enter in reactor three height sections by nozzle 11, contact with the polysilicon crystal seed piling up movement from top to bottom, silane and hydrogen mixed gas thermally decompose at the polysilicon seed surface of heat, the polysilicon deposited is attached to polysilicon seed surface, polysilicon crystal seed particle diameter is made to be gradually increased, tail gas (unreacted SiH after decomposition reaction₄And H₂) it is discharged into cyclone separator 19 from reactor upper separation zone territory, enter back into tail gas recycle, separation and blood circulation 20, enter polycrysalline silcon low level receiving slit 16 with the material outlet 6 bottom silane moving-burden bed reactor 12 of the granular polycrystalline silicon after silane and hydrogen mixed gas haptoreaction, enter back into solid material blood circulation 17 and carry out repeatedly circular response.

E), after repeatedly reaction cycle, the particle diameter of granular polycrystalline silicon is progressively grown up from 0.3mm, when reaching the granular polycrystalline silicon of regulation particle diameter when being recycled to polycrysalline silcon high position receiving slit, screened device is diverted to finished product receiving pipeline to finished product receiving slit 21, enters product handling system system 22；At present, the particle diameter of the granular polycrystalline silicon product of international market is mostly 1mm, and we can be set to product the granular polycrystalline silicon of 1mm particle diameter, it is also possible to increases cycle-index, produces the granular polycrystalline silicon product of bigger particle diameter；The granular polycrystalline silicon product of different-grain diameter, the train design of respective series to be carried out, so could more effectively carry out the production of granular polycrystalline silicon.

Wherein, it is provided with temperature monitor in silane moving-burden bed reactor bottoms material exit, the solid material temperature in exit controls within 550 DEG C, when temperature herein being detected higher than 550 DEG C, then strengthen silane and the flow of hydrogen mixed gas or slow down the circulation rate of solid particle to reduce the temperature at this, enter in outlet conduit and follow-up equipment in order to avoid overheated solid, avoid occurring the temperature of pipeline and follow-up equipment inwall to be raised to produce the situation that silane decomposes, thus reach to avoid pipeline and the purpose of follow-up equipment blocking.

Producing at present polysilicon many employings improved Siemens to produce, the most a small amount of factory have employed silane thermal decomposition process and produces polysilicon, from it is understood that situation from the point of view of, the energy consumption that improved Siemens produces polysilicon is the highest.From the point of view of the feature of silane decomposes, the resolution ratios of about 800 DEG C more than 90%, and producing the reduction technique of the improved Siemens of polysilicon at present, SiHCl3+H2 decomposes restores the conversion ratio of polysilicon less than 12%, reduction temperature about 1050 DEG C.What we calculated use silane moving bed method of piling the produces reduction direct consumption of electr ic energy of granular polycrystalline silicon less than 5 (kw.h/), and at present production of polysilicon enterprise in terms of producing polycrystalline reduction power consumption averagely at 50 (kw.h/).Visible, use silane moving bed method of piling to produce granular polycrystalline silicon it is considered that the energy consumption of production of polysilicon can be substantially reduced.And use the technology of fluid bed production polysilicon because of the restriction of mode of heating, stablizing aspect in production has some problems.Therefore, it is considered that use silane moving bed technique to produce granular polycrystalline silicon can make up the deficiency of silane fluid bed, relatively improved Siemens, uses silane moving bed technique can accomplish continuous production truly, significant to the production cost of energy efficient and reduction polysilicon.

The foregoing is only preferred embodiment of the present utility model, not in order to limit this utility model, all any amendment, equivalent and improvement etc. made within spirit of the present utility model and principle, within should be included in protection domain of the present utility model.

Claims

null1. silane moving-burden bed reactor，It is characterized in that: include reactor shell (1) and polysilicon charge pipe (2)，The discharging port of described polysilicon charge pipe (2) is positioned at reactor shell (1)，The reactor separated region (1a) on top and the reactor reaction region (1b) of bottom it is divided in described reactor shell (1)，The hydrogen inlet (3) connected with reactor separated region (1a) and offgas outlet (4) it is respectively arranged with on described reactor shell (1) top，Multiple reaction mixture gas import (5) connected with reactor reaction region (1b) it is provided with in described reactor shell (1) bottom，Described reactor shell (1) bottom is provided with material outlet (6)，Axial arranged along reactor shell (1) of multiple reaction mixture gas imports (5)，The Inlet Position of multiple differing heights in formation reactor reaction region (1b).
Silane moving-burden bed reactor the most according to claim 1, it is characterized in that: the reactor shell diameter of described reactor separated region (1a) correspondence is the twice of the reactor shell diameter of reactor reaction region (1b) correspondence, and polysilicon crystal seed is deposited in reactor reaction region (1b).
Silane moving-burden bed reactor the most according to claim 1, it is characterised in that: it is internal that described polysilicon charge pipe (2) extends to reactor separated region (1a), and polysilicon crystal seed is accumulated to the discharging port of polysilicon charge pipe (2).
Silane moving-burden bed reactor the most according to claim 1, it is characterised in that: in described reactor separated region (1a), it is provided with dust board (7).
Silane moving-burden bed reactor the most according to claim 1, it is characterised in that: it is lined with polysilicon films (8) at described reactor shell (1) inwall.
Silane moving-burden bed reactor the most according to claim 1, it is characterised in that: described reactor shell (1) periphery is provided with chuck (9).
Silane moving-burden bed reactor the most as claimed in any of claims 1 to 6, it is characterised in that: described reaction mixture gas import (5) is connected with reactor reaction region (1b) by nozzle (11).