CN103449447A

CN103449447A - Equipment for preparing trichlorosilane

Info

Publication number: CN103449447A
Application number: CN2013103737570A
Authority: CN
Inventors: 张升学; 万烨; 严大洲; 毋克力; 肖荣辉; 汤传斌; 杨永亮
Original assignee: China ENFI Engineering Corp
Current assignee: China ENFI Engineering Corp
Priority date: 2013-08-23
Filing date: 2013-08-23
Publication date: 2013-12-18
Anticipated expiration: 2033-08-23
Also published as: CN103449447B

Abstract

The invention discloses equipment for preparing trichlorosilane. The equipment comprises a hydrochlorination synthesis reaction device, and a first distillation purification device, wherein the hydrochlorination synthesis reaction device is used for carrying out hydrochlorination synthesis reaction on ganister sand, hydrogen and at least one material selected from hydrogen chloride and silicon tetrachloride, so as to obtain a hydrochlorination synthesis reaction product containing the trichlorosilane; the first distillation purification device is used for carrying out first distillation purification treatment on the hydrochlorination synthesis reaction product containing the trichlorosilane, so as to obtain the trichlorosilane and first refined raffinate. By using the equipment, the trichlorosilane can be effectively prepared; the process related to the equipment is simple, safe, energy-saving and environment-friendly, low in cost, and high in purity of produced trichlorosilane; the generated tail gas and waste residue can be recycled, so as to achieve the environmental requirements.

Description

The equipment for preparing trichlorosilane

Technical field

The present invention relates to the photovoltaic industry technical field, particularly, relate to the equipment for preparing trichlorosilane.

Background technology

Sun power has been subject to global attention as a kind of renewable and clean energy resource, and the technology of utilizing solar energy resources to generate electricity has been considered to the most promising new energy technology in the current whole world.Thereby the photovoltaic industry that the solar energy generation technology of take is core has obtained swift and violent development at the beginning of 21 century.Polysilicon is as the main raw material(s) of photovoltaic industry, and along with the fast development of photovoltaic industry, its demand significantly increases.And then the demand of producing the main raw material trichlorosilane of polysilicon also increases thereupon.

Yet, present stage preparation technology and the equipment of trichlorosilane still remain to be improved.

Summary of the invention

The following discovery that the present invention is based on the contriver completes:

The production of polysilicon technique of having reported at present is more, but production efficiency is lower, and cost is higher, and producing intermediate product needs further to purify and separate, and separating difficulty is larger, produces liquid and waste slag produced many, seriously polluted.Thereby, seek a kind of cost electronic-grade polycrystalline silicon production method low, that consume energy few imperative.And then, find that a kind of cost is low, power consumption less, the preparation technology of the production of polysilicon main raw material trichlorosilane of energy-conserving and environment-protective, clean, also significant.

The present invention is intended at least solve one of technical problem existed in prior art.For this reason, one object of the present invention is to propose the equipment that a kind of low-cost energy-saving environmental protection ground produces trichlorosilane.

According to an aspect of the present invention, the present invention proposes a kind of equipment for the preparation of trichlorosilane.According to embodiments of the invention, this equipment comprises: chlorine hydrogenation synthetic reaction device, described chlorine hydrogenation synthetic reaction device is for making silica flour, hydrogen and being selected from hydrogenchloride and at least one generation chlorine hydrogenation building-up reactions of silicon tetrachloride, in order to obtain the chlorine hydrogenation building-up reactions product that comprises trichlorosilane; And the first rectifying purification devices, described the first rectifying purification devices is connected with described chlorine hydrogenation synthetic reaction device, for the described chlorine hydrogenation building-up reactions product that comprises trichlorosilane is carried out to the first rectifying purification process, in order to obtain trichlorosilane and the first distillation residual liquid.

The contriver is surprised to find, utilize this equipment can effectively prepare trichlorosilane, and the technique that this equipment relates to is simple, safety, energy-conserving and environment-protective, cost are low, and the purity of trichlorosilane of producing is high, can be effective to the production of electronic-grade polycrystalline silicon, the tail gas and the waste residue that produce can be utilized again, thus meet the requirement of environmental protection.

In addition, the equipment for the preparation of trichlorosilane according to the above embodiment of the present invention can also have following additional technical characterictic:

According to embodiments of the invention, be provided with nickel-base catalyst or copper-based catalysts in described chlorine hydrogenation synthetic reaction device, so that when having nickel-base catalyst or copper-based catalysts, the gaseous mixture that comprises silicon tetrachloride and hydrogen is contacted with silica flour, described chlorine hydrogenation building-up reactions occurs.Thus, can effectively improve the efficiency of chlorine hydrogenation building-up reactions, be conducive to trichlorosilane and generate, and the carrying out of subsequent purification step.

According to embodiments of the invention, in the described gaseous mixture that comprises silicon tetrachloride and hydrogen, the mol ratio of silicon tetrachloride and hydrogen is 1:2～5.Thus, the efficiency of chlorine hydrogenation building-up reactions significantly improves, and be conducive to trichlorosilane and generate, and the carrying out of subsequent purification step.

According to embodiments of the invention, described chlorine hydrogenation building-up reactions is to carry out at the temperature of 500～550 degrees centigrade.

According to embodiments of the invention, described chlorine hydrogenation building-up reactions is at 500～550 degrees centigrade, under the condition of 1.5～3.5MPa, carries out.Thus, the efficiency of chlorine hydrogenation building-up reactions is high, and be conducive to trichlorosilane and generate, and the carrying out of subsequent purification step.

According to embodiments of the invention, further comprise: Liqiud-gas mixing device, described Liqiud-gas mixing device, for silicon tetrachloride liquid is mixed with hydrogen, obtains gas-liquid mixture; Heat exchanger, described heat exchanger is connected with described chlorine hydrogenation synthetic reaction device with described Liqiud-gas mixing device respectively, for utilizing described chlorine hydrogenation building-up reactions product to carry out heat exchange process to described gas-liquid mixture, in order to obtain through the gas-liquid mixture of preheating with through overcooled chlorine hydrogenation building-up reactions product; And resistance heater, described resistance heater is connected with described chlorine hydrogenation synthetic reaction device with described heat exchanger respectively, for the gas-liquid mixture to through preheating, heated, in order to obtain the described gaseous mixture that comprises silicon tetrachloride and hydrogen, and the described gaseous mixture that comprises silicon tetrachloride and hydrogen is supplied to described chlorine hydrogenation synthetic reaction device.Thus, can in the situation that power consumption minimumly realize the cooling of chlorine hydrogenation building-up reactions product simultaneously and gas-liquid mixture carried out to preheating, and can effectively obtain the gaseous mixture that comprises silicon tetrachloride and hydrogen, for chlorine hydrogenation building-up reactions in follow-up circulation is supplied raw materials, thereby can effectively realize energy-conserving and environment-protective, the purpose reduced costs.

According to embodiments of the invention, further comprise: cleaning apparatus, described cleaning apparatus is connected with described heat exchanger, in order to carry out dust removal process by described through overcooled chlorine hydrogenation building-up reactions product; And first condensing works, described the first condensing works is connected with the first rectifying purification devices with described cleaning apparatus respectively, for carrying out condensation through the chlorine hydrogenation building-up reactions product of dust removal process, so that difference recover hydrogen and chlorosilane liquid produced, described chlorosilane liquid produced comprises trichlorosilane and silicon tetrachloride, and described chlorosilane liquid produced is supplied to described the first rectifying purification devices for described the first rectifying purification process.Thus, after overcooled chlorine hydrogenation building-up reactions product is by above-mentioned processing, can obtain chlorosilane liquid produced and hydrogen, and chlorosilane liquid produced and hydrogen can be supplied to respectively the related device for the preparation of the equipment of polysilicon, carry out recycle again, thereby can effectively realize energy-conserving and environment-protective, the purpose reduced costs.

According to embodiments of the invention, described the first condensing works is connected with described chlorine hydrogenation synthetic reaction device, for described hydrogen being supplied to described chlorine hydrogenation synthetic reaction device.Thus, hydrogen can be recycled, for the chlorine hydrogenation building-up reactions of carrying out in chlorine hydrogenation synthetic reaction device is supplied raw materials, energy-conserving and environment-protective, and can reduce production costs.

According to embodiments of the invention, described the first rectifying purification devices comprises a plurality of rectifying tower of series connection, and wherein, each rectifying tower all arranges respectively opening for feed and discharge port from bottom to top along the axial direction due of described rectifying tower.Thus, can effectively improve the efficiency of rectifying purification process in the first rectifying purification devices, thereby can obtain highly purified trichlorosilane.

According to embodiments of the invention, described the first rectifying purification devices comprises the first rectifying tower, Second distillation column and the 3rd rectifying tower of series connection.Thus, can guarantee suitable production cost and higher rectifying purification efficiency simultaneously, thereby can obtain highly purified trichlorosilane.

According to embodiments of the invention, the rectification temperature of described the first rectifying tower is 60～100 degrees centigrade, and pressure is 0.2MPa, and reflux ratio is 10～50:1; The rectification temperature of described Second distillation column is 100～140 degrees centigrade, and pressure is 0.5MPa, and reflux ratio is 20～50:1; The rectification temperature of described the 3rd rectifying tower is 60～80 degrees centigrade, and pressure is 0.2MPa, and reflux ratio is 20～50:1.Thus, can guarantee the safety in production, and the power consumption less, production cost is low, the rectifying purification efficiency is high, effective, thereby can obtain highly purified trichlorosilane.

According to embodiments of the invention, equipment of the present invention further comprises: the disproportionation reaction device, described disproportionation reaction device is connected with described the first rectifying purification devices, for making described trichlorosilane generation disproportionation reaction, in order to obtain the disproportionation reaction product that comprises silicon tetrachloride and silane; The second rectifying purification devices, described the second rectifying purification devices is connected with described disproportionation reaction device, for described disproportionation reaction product is carried out to the second rectifying purification process, in order to obtain silane gas and silicon tetrachloride; And the pyrolytic reaction device, described pyrolytic reaction device is connected with described the second rectifying purification devices, for making described silane gas generation pyrolytic reaction, in order to obtain polysilicon.Thus, the highly purified trichlorosilane that the present invention prepares can be effective to the production of electronic-grade polycrystalline silicon, thereby based on above-mentioned various annexations, of the present invention for the preparation of trichlorosilane equipment and above-mentioned each device can effectively be formed for preparing the equipment of electronic-grade polycrystalline silicon, and should be low for the preparation of device fabrication cost of electronic-grade polycrystalline silicon, power consumption less, energy-conserving and environment-protective, the polysilicon purity of production is very high.

According to embodiments of the invention, at least a portion of described silicon tetrachloride derives from described disproportionation reaction device.Thus, the silicon tetrachloride be about in the disproportionation reaction product has carried out recycle, thereby can realize energy-conserving and environment-protective, the purpose reduced costs.

According to embodiments of the invention, described the second rectifying purification devices is connected with described chlorine hydrogenation synthesizer, so as by the silicon tetrachloride that obtains in described the second rectifying purification devices for described chlorine hydrogenation building-up reactions.Thus, the silicon tetrachloride in the second rectifying purification devices product has been carried out to recycle, thereby can realize energy-conserving and environment-protective, the purpose reduced costs.

According to embodiments of the invention, in described disproportionation reaction device, described disproportionation reaction is at 50～80 degrees centigrade, under the condition of 0.2～0.6MPa, carries out.Thus, production safety, and the power consumption less, production cost is low, disproportionation reaction efficiency is high, effective, is conducive to the carrying out of subsequent step.

According to embodiments of the invention, described disproportionation reaction device is disproportionation reactor, described disproportionation reactor further comprises: the disproportionation reactor body limits the disproportionation reaction space in described disproportionation reactor body, and is provided with catalyst layer in described disproportionation reaction space; The trichlorosilane opening for feed, described trichlorosilane opening for feed is arranged on the below of described catalyst layer, for to described disproportionation reaction space, supplying with trichlorosilane; And disproportionation reaction product discharge port, described disproportionation reaction product discharge port is arranged on the top of described catalyst layer, for the formed disproportionation reaction product that comprises silicon tetrachloride and silane is discharged to described disproportionation reactor.Thus, disproportionation reaction efficiency is high, effective, and production safety, power consumption less, cost is low, the carrying out that be conducive to subsequent step.

According to embodiments of the invention, described the second rectifying purification devices is low-temperature fractionating tower, and wherein, the temperature in described low-temperature fractionating tower is-60～-80 degrees centigrade, and pressure is 0.6～1.0MPa, and reflux ratio is 5～20:1.Thus, production safety, and the power consumption less, production cost is low, the rectifying purification efficiency is high, effective, is conducive to the carrying out of subsequent step.

According to embodiments of the invention, further comprise the vaporization process device, described vaporization process device is connected with described pyrolytic reaction device with described the second rectifying purification devices respectively, and for before pyrolytic reaction, the silane gas that will store with liquid form in advance carries out vaporization process.Thus, be conducive to the carrying out of pyrolytic reaction in the pyrolytic reaction device, thereby can effectively prepare polysilicon, and cost is low, needing can be few, energy-conserving and environment-protective, and pyrolytic reaction efficiency is high.

According to embodiments of the invention, described pyrolytic reaction device is reduction furnace, is provided with the carrier of silicon core as crystal deposition in described reduction furnace.Thus, pyrolytic reaction efficiency is high, effective, and the electronic-grade polycrystalline silicon purity prepared is high.

According to embodiments of the invention, described reduction furnace is the bell-jar reduction furnace.Thus, pyrolytic reaction efficiency is high, effective.

According to embodiments of the invention, be provided with 12,24 or 36 pairs of silicon rods in described reduction furnace.Thus, adopt the silicon core as carrier.Further, according to embodiments of the invention, also be provided with the cooling jacket consistent with silicon core logarithm in reduction furnace.Thereby, be conducive to silane gas checking solution deposition, prepare high-purity electronic-grade polycrystalline silicon.

According to embodiments of the invention, the temperature in described reduction furnace is 750～900 degrees centigrade, and pressure is 0.15～0.30MPa.Thus, pyrolytic reaction efficiency is high, effective, and reaction safety, and the electronic-grade polycrystalline silicon purity prepared is high.

According to embodiments of the invention, further comprise: the flash distillation treatment unit, described flash distillation treatment unit is connected with described the first rectifying purification devices, for described the first distillation residual liquid is carried out to the flash distillation processing, in order to obtain silicon tetrachloride gas and solid residue; The second condensing works, described the second condensing works is connected with described Liqiud-gas mixing device with described flash distillation treatment unit respectively, for described silicon tetrachloride gas is carried out to condensation process, so that acquisition silicon tetrachloride liquid, and described silicon tetrachloride liquid is supplied to described Liqiud-gas mixing device, for described chlorine hydrogenation building-up reactions; And the residue treatment device, described residue treatment device is connected with described flash distillation treatment unit, for described solid residue being carried out successively to alkali lye hydrolysis neutralizing treatment and press filtration, processes.Thus, can effectively realize the cycling and reutilization of the first distillation residual liquid, thereby reach energy-conserving and environment-protective, the purpose reduced costs.

According to embodiments of the invention, further comprise: the first compression set, described the first compression set is connected with described pyrolytic reaction device, and being compressed to pressure for the reduction tail gas by pyrolytic reaction is 6.0～10.0MPa; And the 3rd condensing works, described the 3rd condensing works is connected with described the first compression set, described Liqiud-gas mixing device and described vaporization process device, being used for to be-100～-120 degrees centigrade through reduction tail gas condensing to the temperature of overdraft, in order to silane gas is condensed into to silane liquid and obtains hydrogen, and by described silane liquid supply to described vaporization process device, described hydrogen is supplied to described Liqiud-gas mixing device, for described chlorine hydrogenation building-up reactions.Thus, can effectively to the reduction tail gas produced in the pyrolytic reaction device, be processed, be realized non-pollution discharge, be guaranteed cleaner production, and be realized the cycling and reutilization of reduction tail gas, thereby be reached energy-conserving and environment-protective, the purpose reduced costs.

According to embodiments of the invention, further comprise: the second compression set, described the second compression set is 0.25～0.50MPa for each device is produced contain chlorosilane but containing the tail gas of silane, be not compressed to pressure; The 4th condensing works, described the 4th condensing works is connected with described the first rectifying purification devices with described the second compression set respectively, for will through overdraft to contain chlorosilane but containing the tail gas of silane, be not cooled to temperature be-15～-30 degrees centigrade, in order to obtain chlorosilane liquid produced and residual gas, and described chlorosilane liquid produced be supplied to described the first rectifying purification devices for described the first rectifying purification process; Elution device, described elution device is connected with described the 4th condensing works, for described residual gas is carried out to drip washing, in order to obtain gas and the washing water through drip washing; And the washing water treatment unit, described washing water treatment unit is connected with described elution device, for utilizing alkali lye, described washing water is neutralized, and carries out press filtration to neutralizing rear liquid, so that in obtaining and water and filter residue.Thus, can effectively to what produce in each device, contain chlorosilane but do not processed containing the tail gas of silane, realize non-pollution discharge, guarantee cleaner production, and realize the cycling and reutilization of tail gas, thereby reach energy-conserving and environment-protective, the purpose reduced costs.

According to embodiments of the invention, by described and water supply to described elution device, for described residual gas is carried out to drip washing.Thus, can by and water carry out recycle, thereby reduce production costs, and realize non-pollution discharge, guarantee cleaner production.

It should be noted that, with respect to prior art, the equipment for the preparation of trichlorosilane of the present invention has the following advantages:

1, the whole process system safety and stability related to, technique is simple, can realize.

2, production cost purity of trichlorosilane low, that prepare is high, the energy saving technology environmental protection.

3, the equipment for the preparation of trichlorosilane of the present invention can with the effectively combination such as aforesaid disproportionation reaction device, the second rectifying purification devices and pyrolytic reaction device, thereby form the new equipment for the preparation of electronic-grade polycrystalline silicon, and should can effectively realize that by the trichlorosilane one stage disproportionation be silane gas for the preparation of the equipment of electronic-grade polycrystalline silicon; Silane gas and chlorosilane are easily separated, and after purifying, purity is high, more than can reaching 9N; The silane gas checking solution temperature obtained is lower, and energy consumption is lower, and then the cost of production polysilicon is lower; The polysilicon of preparation is electronic-grade polycrystalline silicon, and purity is high, can reach 9N-11N; Tail gas and the waste residue of discharge all meet environmental requirement, are polysilicon cleaner production equipment.

Additional aspect of the present invention and advantage part in the following description provide, and part will become obviously from the following description, or recognize by practice of the present invention.

The accompanying drawing explanation

Above-mentioned and/or additional aspect of the present invention and advantage are from obviously and easily understanding becoming the description of embodiment in conjunction with following accompanying drawing, wherein:

Fig. 1 has shown the schematic flow sheet for preparing according to an embodiment of the invention the method for polysilicon;

Fig. 2 has shown the schematic flow sheet for preparing according to an embodiment of the invention the method for polysilicon;

Fig. 3 has shown according to an embodiment of the invention the structural representation for the preparation of the equipment of polysilicon;

Fig. 4-Figure 11 has shown respectively according to an embodiment of the invention the local structure schematic diagram for the preparation of the equipment of polysilicon;

Figure 12 has shown according to an embodiment of the invention the structural representation for the preparation of the equipment of trichlorosilane.

Embodiment

Below describe embodiments of the invention in detail, the example of described embodiment is shown in the drawings, and wherein same or similar label means same or similar element or the element with identical or similar functions from start to finish.Be exemplary below by the embodiment be described with reference to the drawings, only for explaining the present invention, and can not be interpreted as limitation of the present invention.

In description of the invention, term " axially ", " on ", orientation or the position relationship of the indications such as D score, " top ", " end " be based on orientation shown in the drawings or position relationship, be only the present invention for convenience of description rather than require the present invention with specific orientation structure and operation, therefore can not be interpreted as limitation of the present invention.

In the present invention, broad understanding should be done in the terms such as unless otherwise clearly defined and limited, term " is connected ", " connection ", " fixing ", for example, can be to be fixedly connected with, and can be also to removably connect, or connect integratedly; Can be mechanical connection, can be also to be electrically connected to; Can be directly to be connected, also can indirectly be connected by intermediary, can be the connection of two element internals.For the ordinary skill in the art, can understand as the case may be above-mentioned term concrete meaning in the present invention.

In the present invention, unless otherwise clearly defined and limited, First Characteristic Second Characteristic it " on " or D score can comprise that the first and second features directly contact, also can comprise that the first and second features are not directly contacts but by the other feature contact between them.And, First Characteristic Second Characteristic " on ", " top " and " above " comprise First Characteristic directly over Second Characteristic and oblique upper, or only mean that the First Characteristic level height is higher than Second Characteristic.First Characteristic Second Characteristic " under ", " below " and " below " comprise First Characteristic under Second Characteristic and tiltedly, or only mean that the First Characteristic level height is less than Second Characteristic.

It should be noted that, term " first ", " second " be only for describing purpose, and can not be interpreted as indication or hint relative importance or the implicit quantity that indicates indicated technical characterictic.Thus, one or more these features can be expressed or impliedly be comprised to the feature that is limited with " first ", " second ".

According to an aspect of the present invention, the present invention proposes a kind of equipment for the preparation of trichlorosilane.According to embodiments of the invention, with reference to Figure 12, the equipment for the preparation of trichlorosilane of the present invention comprises: chlorine hydrogenation synthetic reaction device 1 and the first rectifying purification devices 2.According to some embodiments of the invention, described chlorine hydrogenation synthetic reaction device 1 is for making silica flour, hydrogen and being selected from hydrogenchloride and at least one generation chlorine hydrogenation building-up reactions of silicon tetrachloride, in order to obtain the chlorine hydrogenation building-up reactions product that comprises trichlorosilane; Described the first rectifying purification devices 2 is connected with described chlorine hydrogenation synthetic reaction device 1, for the described chlorine hydrogenation building-up reactions product that comprises trichlorosilane is carried out to the first rectifying purification process, in order to obtain trichlorosilane and the first distillation residual liquid.

In addition, according to embodiments of the invention, with reference to Fig. 3, the equipment for the preparation of trichlorosilane of the present invention may further include: disproportionation reaction device 3, the second rectifying purification devices 4 and pyrolytic reaction device 5.According to some embodiments of the present invention, disproportionation reaction device 3 is connected with above-mentioned the first rectifying purification devices 2, for making described trichlorosilane generation disproportionation reaction, in order to obtain the disproportionation reaction product that comprises silicon tetrachloride and silane; The second rectifying purification devices 4 is connected with disproportionation reaction device 3, for described disproportionation reaction product is carried out to the second rectifying purification process, in order to obtain silane gas and silicon tetrachloride; Pyrolytic reaction device 5 is connected with the second rectifying purification devices 4, for making described silane gas generation pyrolytic reaction, in order to obtain polysilicon.

Thus, the highly purified trichlorosilane that the present invention prepares can be effective to the production of electronic-grade polycrystalline silicon, and then the various annexations based on above-mentioned, of the present invention for the preparation of trichlorosilane equipment and above-mentioned each the device effectively combination, thereby form a kind of new equipment for the preparation of electronic-grade polycrystalline silicon, and should be low for the preparation of device fabrication cost of electronic-grade polycrystalline silicon, power consumption less, energy-conserving and environment-protective, the polysilicon purity of production is very high.

Thereby, according to a further aspect in the invention, the invention allows for a kind of equipment for the preparation of polysilicon.According to embodiments of the invention, with reference to Fig. 3, the equipment for the preparation of polysilicon of the present invention comprises: chlorine hydrogenation synthetic reaction device 1, the first rectifying purification devices 2, disproportionation reaction device 3, the second rectifying purification devices 4 and pyrolytic reaction device 5.According to some embodiments of the invention, described chlorine hydrogenation synthetic reaction device 1 is for making silica flour, hydrogen and being selected from hydrogenchloride and at least one generation chlorine hydrogenation building-up reactions of silicon tetrachloride, in order to obtain the chlorine hydrogenation building-up reactions product that comprises trichlorosilane; Described the first rectifying purification devices 2 is connected with described chlorine hydrogenation synthetic reaction device 1, for the described chlorine hydrogenation building-up reactions product that comprises trichlorosilane is carried out to the first rectifying purification process, in order to obtain trichlorosilane and the first distillation residual liquid; Described disproportionation reaction device 3 is connected with described the first rectifying purification devices 2, for making described trichlorosilane generation disproportionation reaction, in order to obtain the disproportionation reaction product that comprises silicon tetrachloride and silane; Described the second rectifying purification devices 4 is connected with described disproportionation reaction device 3, for described disproportionation reaction product is carried out to the second rectifying purification process, in order to obtain silane gas and silicon tetrachloride; Described pyrolytic reaction device 5 is connected with described the second rectifying purification devices 4, for making described silane gas generation pyrolytic reaction, in order to obtain polysilicon.The contriver is surprised to find, utilize this equipment can effectively prepare electronic-grade polycrystalline silicon, and the technique that this equipment relates to is simple, safety, energy-conserving and environment-protective, cost are low, and the polysilicon purity of producing is high, the tail gas produced and waste residue can meet the requirement of environmental protections, are the electronic-grade polycrystalline silicon process for cleanly preparing.

In order to make those skilled in the art more easily understand the method for polysilicon and the applicable equipment thereof of preparing of the present invention, below in conjunction with Fig. 3-Figure 11, the Whole Equipment for the preparation of polysilicon of the present invention and local structure and function thereof are described in detail.

Wherein, it should be noted that, each accompanying drawing reaches described " STC " herein and refers to silicon tetrachloride, and " TCS " refers to trichlorosilane.

According to embodiments of the invention, in the chlorine hydrogenation synthetic reaction device 1 shown in Fig. 3, the condition of chlorine hydrogenation building-up reactions is not particularly limited.According to concrete examples more of the present invention, be provided with nickel-base catalyst or copper-based catalysts in chlorine hydrogenation synthetic reaction device 1, so that when having nickel-base catalyst or copper-based catalysts, the gaseous mixture that comprises silicon tetrachloride and hydrogen is contacted with silica flour, described chlorine hydrogenation building-up reactions occurs.Wherein, the chemical reaction related generally to is: 3SiCl ₄+ 2H ₂+ Si---4SiHCl ₃.Thus, can effectively improve the efficiency of chlorine hydrogenation building-up reactions, be conducive to subsequent step and carry out.Wherein, in the gaseous mixture that comprises silicon tetrachloride and hydrogen, the ratio of silicon tetrachloride and hydrogen is not particularly limited.According to embodiments of the invention, in the described gaseous mixture that comprises silicon tetrachloride and hydrogen, the mol ratio of silicon tetrachloride and hydrogen is 1:2～5.Thus, the efficiency of chlorine hydrogenation building-up reactions significantly improves, and is conducive to subsequent step and carries out.

According to embodiments of the invention, the temperature and pressure that carries out chlorine hydrogenation building-up reactions in chlorine hydrogenation synthetic reaction device 1 is not particularly limited, as long as can effectively be reacted, obtains the chlorine hydrogenation building-up reactions product that comprises trichlorosilane and gets final product.According to some embodiments of the present invention, described chlorine hydrogenation building-up reactions is to carry out at the temperature of 500～550 degrees centigrade.According to other embodiment of the present invention, described chlorine hydrogenation building-up reactions is at 500～550 degrees centigrade, under the condition of 1.5～3.5MPa, carries out.Thus, the efficiency of chlorine hydrogenation building-up reactions is high, is conducive to subsequent step and carries out.

In addition, the source of the silicon tetrachloride adopted in chlorine hydrogenation synthetic reaction device 1 is not particularly limited, and can directly provide, and also can from the reaction product of subsequent step or waste liquid, separate and obtain.According to embodiments of the invention, at least a portion of described silicon tetrachloride derives from described disproportionation reaction device 3.Thus, the silicon tetrachloride be about in the disproportionation reaction product has carried out recycle, thereby can realize energy-conserving and environment-protective, the purpose reduced costs.

According to embodiments of the invention, described the second rectifying purification devices 4 (not shown) that is connected with described chlorine hydrogenation synthesizer 1 so that by the silicon tetrachloride that obtains in described the second rectifying purification devices for described chlorine hydrogenation building-up reactions.Thus, the silicon tetrachloride produced in the second rectifying purification devices can be carried out to recycle, thereby can realize energy-conserving and environment-protective, the purpose reduced costs.

According to embodiments of the invention, with reference to Fig. 4, the equipment for the preparation of polysilicon of the present invention may further include: Liqiud-gas mixing device 6, heat exchanger 7 and resistance heater 8.According to embodiments of the invention, described Liqiud-gas mixing device 6, for silicon tetrachloride liquid is mixed with hydrogen, obtains gas-liquid mixture; Described heat exchanger 7 is connected with described chlorine hydrogenation synthetic reaction device 1 with described Liqiud-gas mixing device 6 respectively, for utilizing described chlorine hydrogenation building-up reactions product to carry out heat exchange process to described gas-liquid mixture, in order to obtain through the gas-liquid mixture of preheating with through overcooled chlorine hydrogenation building-up reactions product; Described resistance heater 8 is connected with described chlorine hydrogenation synthetic reaction device 1 with described heat exchanger 7 respectively, for the gas-liquid mixture to through preheating, heated, in order to obtain the described gaseous mixture that comprises silicon tetrachloride and hydrogen, and the described gaseous mixture that comprises silicon tetrachloride and hydrogen is supplied to described chlorine hydrogenation synthetic reaction device 1.Thus, can in the situation that power consumption minimumly realize the cooling of chlorine hydrogenation building-up reactions product simultaneously and gas-liquid mixture carried out to preheating, and can effectively obtain the gaseous mixture that comprises silicon tetrachloride and hydrogen, for chlorine hydrogenation building-up reactions in follow-up circulation is supplied raw materials, thereby can effectively realize energy-conserving and environment-protective, the purpose reduced costs.

According to embodiments of the invention, with reference to Fig. 4, the equipment for the preparation of polysilicon of the present invention may further include: cleaning apparatus 9 and the first condensing works 10.According to embodiments of the invention, cleaning apparatus 9 is connected with heat exchanger 7, in order to carry out dust removal process by described through overcooled chlorine hydrogenation building-up reactions product; The first condensing works 10 is connected with the first rectifying purification devices 2 with cleaning apparatus 9 respectively, for carrying out condensation through the chlorine hydrogenation building-up reactions product of dust removal process, so that difference recover hydrogen and chlorosilane liquid produced, described chlorosilane liquid produced comprises trichlorosilane and silicon tetrachloride, and described chlorosilane liquid produced is supplied to described the first rectifying purification devices 2 for described the first rectifying purification process.Thus, after overcooled chlorine hydrogenation building-up reactions product is by above-mentioned processing, can obtain chlorosilane liquid produced and hydrogen, and chlorosilane liquid produced and hydrogen can be supplied to respectively the related device of equipment of the present invention, carry out recycle again, thereby can effectively realize energy-conserving and environment-protective, the purpose reduced costs.

According to embodiments of the invention, described the first condensing works 10 is connected with described chlorine hydrogenation synthetic reaction device 1, for described hydrogen being supplied to described chlorine hydrogenation synthetic reaction device 1.Thus, hydrogen can be recycled, for the chlorine hydrogenation building-up reactions of carrying out in chlorine hydrogenation synthetic reaction device is supplied raw materials, energy-conserving and environment-protective, and can reduce production costs.

According to embodiments of the invention, described the first rectifying purification devices 2 comprises a plurality of rectifying tower of series connection, and wherein, each rectifying tower all arranges respectively opening for feed and discharge port from bottom to top along the axial direction due of described rectifying tower.Thus, can be used in the material that carries out rectification process and be along the axial direction due of each rectifying tower and move from bottom to top, thereby can effectively improve the efficiency of rectifying purification process in the first rectifying purification devices, be conducive to the carrying out of subsequent step.

According to concrete examples more of the present invention, with reference to Fig. 5, the first rectifying purification devices 2 comprises the first rectifying tower 21, Second distillation column 22 and the 3rd rectifying tower 23 of series connection.Thus, can guarantee suitable production cost and higher rectifying purification efficiency simultaneously, be conducive to the carrying out of subsequent step.Wherein, the condition of carrying out the first rectifying purification process in the first rectifying purification devices 2 is that the reaction conditions in each rectifying tower is not particularly limited, as long as can from the chlorine hydrogenation building-up reactions product that comprises trichlorosilane, obtain trichlorosilane by effective purifying.According to embodiments of the invention, the rectification temperature of described the first rectifying tower 21 is 60～100 degrees centigrade, and pressure is 0.2MPa, and reflux ratio is 10～50:1; The rectification temperature of described Second distillation column 22 is 100～140 degrees centigrade, and pressure is 0.5MPa, and reflux ratio is 20～50:1; The rectification temperature of described the 3rd rectifying tower 23 is 60～80 degrees centigrade, and pressure is 0.2MPa, and reflux ratio is 20～50:1.Thus, can guarantee the safety in production, and the power consumption less, production cost is low, the rectifying purification efficiency is high, effective, is conducive to the carrying out of subsequent step.

Wherein, the chemical reaction related in disproportionation reaction device 3 is mainly: 4SiHCl ₃---SiH ₄+ 3SiCl ₄.And, according to embodiments of the invention, the condition of carrying out disproportionation reaction in disproportionation reaction device 3 is not particularly limited, as long as can carry out safely the disproportionation reaction of trichlorosilane, effectively obtains the disproportionation reaction product and get final product.According to concrete examples more of the present invention, in described disproportionation reaction device 3, described disproportionation reaction is at 50～80 degrees centigrade, under the condition of 0.2～0.6MPa, carries out.Thus, production safety, and the power consumption less, production cost is low, disproportionation reaction efficiency is high, effective, is conducive to the carrying out of subsequent step.

According to embodiments of the invention, disproportionation reaction device 3 is disproportionation reactor, and with reference to Fig. 6, described disproportionation reactor further comprises: disproportionation reactor body 31, trichlorosilane opening for feed 34 and disproportionation reaction product discharge port 35.Wherein, according to embodiments of the invention, in described disproportionation reactor body 31, limit disproportionation reaction space 32, and be provided with catalyst layer 33 in described disproportionation reaction space 32; Described trichlorosilane opening for feed 34 is arranged on the below of described catalyst layer 33, for to described disproportionation reaction space 32, supplying with trichlorosilane; Described disproportionation reaction product discharge port 35 is arranged on the top of described catalyst layer 33, for the formed disproportionation reaction product that comprises silicon tetrachloride and silane is discharged to described disproportionation reactor.Thus, disproportionation reaction efficiency is high, effective, and production safety, power consumption less, cost is low, the carrying out that be conducive to subsequent step.

According to embodiments of the invention, the type of the second rectifying purification devices 4 and the condition of wherein being processed are not particularly limited.According to concrete examples more of the present invention, with reference to Fig. 7, described the second rectifying purification devices 4 is low-temperature fractionating tower, and wherein, the temperature in described low-temperature fractionating tower is-60～-80 degrees centigrade, and pressure is 0.6～1.0MPa, and reflux ratio is 5～20:1.Thus, production safety, and the power consumption less, production cost is low, the rectifying purification efficiency is high, effective, is conducive to the carrying out of subsequent step.

According to embodiments of the invention, with reference to Fig. 8, equipment for the preparation of polysilicon of the present invention may further include vaporization process device 11, described vaporization process device 11 is connected with described pyrolytic reaction device 5 with described the second rectifying purification devices 4 respectively, for before pyrolytic reaction, the silane gas that will store with liquid form in advance carries out vaporization process.Thus, be conducive to the carrying out of pyrolytic reaction in the pyrolytic reaction device, thereby can effectively prepare polysilicon, and cost is low, needing can be few, energy-conserving and environment-protective, and pyrolytic reaction efficiency is high.

According to embodiments of the invention, the type of pyrolytic reaction device is not particularly limited.According to concrete examples more of the present invention, described pyrolytic reaction device 5 is reduction furnace, is provided with the carrier of silicon core as crystal deposition in described reduction furnace.Thus, pyrolytic reaction efficiency is high, effective, and the electronic-grade polycrystalline silicon purity prepared is high.According to other embodiment of the present invention, with reference to Fig. 8, described reduction furnace is the bell-jar reduction furnace.Thus, pyrolytic reaction efficiency is high, effective.In addition, temperature, pressure condition in reduction furnace in the quantity of silicon rod and reduction furnace also are not particularly limited, as long as be conducive to pyrolytic reaction.According to embodiments of the invention, be provided with 12,24 or 36 pairs of silicon rods in described reduction furnace.Thus, can adopt the silicon core as carrier.Further, according to embodiments of the invention, also be provided with the cooling jacket consistent with silicon core logarithm in reduction furnace.Thereby, be conducive to silane gas checking solution deposition, prepare high-purity electronic-grade polycrystalline silicon.According to other embodiment of the present invention, the temperature in described reduction furnace is 750～900 degrees centigrade, and pressure is 0.15～0.30MPa.Thus, pyrolytic reaction efficiency is high, effective, and reaction safety, and the electronic-grade polycrystalline silicon purity prepared is high.

According to embodiments of the invention, with reference to Fig. 9, the equipment for the preparation of polysilicon of the present invention can further include: flash distillation treatment unit 12, the second condensing works 13 and residue treatment device 14.According to embodiments of the invention, as shown in Figure 9, described flash distillation treatment unit 12 is connected with described the first rectifying purification devices 2, for described the first distillation residual liquid is carried out to the flash distillation processing, in order to obtain silicon tetrachloride gas and solid residue; Described the second condensing works 13 is connected with described Liqiud-gas mixing device 6 with described flash distillation treatment unit 12 respectively, for described silicon tetrachloride gas is carried out to condensation process, so that acquisition silicon tetrachloride liquid, and described silicon tetrachloride liquid is supplied to described Liqiud-gas mixing device 6, for described chlorine hydrogenation building-up reactions; Described residue treatment device 14 is connected with described flash distillation treatment unit 12, for described solid residue being carried out successively to alkali lye hydrolysis neutralizing treatment and press filtration, processes.Thus, can effectively realize the cycling and reutilization of the first distillation residual liquid, thereby reach energy-conserving and environment-protective, the purpose reduced costs.Wherein, it should be noted that, when the first rectifying purification devices 2 as shown in Figure 5, during for first rectifying tower, Second distillation column of series connection and the 3rd rectifying tower, the first distillation residual liquid is the raffinate that discharge the Second distillation column bottom.

According to embodiments of the invention, with reference to Figure 10, equipment for the preparation of polysilicon of the present invention may further include: the first compression set 15 and the 3rd condensing works 16, according to embodiments of the invention, described the first compression set 15 is connected with described pyrolytic reaction device 5, and being compressed to pressure for the reduction tail gas by pyrolytic reaction is 6.0～10.0MPa; Described the 3rd condensing works 16 is connected with described the first compression set 15, described Liqiud-gas mixing device 6 and described vaporization process device 11, being used for to be-100～-120 degrees centigrade through reduction tail gas condensing to the temperature of overdraft, in order to silane gas is condensed into to silane liquid and obtains hydrogen, and by described silane liquid supply to described vaporization process device 11, described hydrogen is supplied to described Liqiud-gas mixing device 6, for described chlorine hydrogenation building-up reactions.Thus, can effectively to the reduction tail gas produced in the pyrolytic reaction device, be processed, be realized non-pollution discharge, be guaranteed cleaner production, and be realized the cycling and reutilization of reduction tail gas, thereby be reached energy-conserving and environment-protective, the purpose reduced costs.

According to embodiments of the invention, with reference to Figure 11, the equipment for the preparation of polysilicon of the present invention can further include: the second compression set 17, the 4th condensing works 18, elution device 19 and washing water treatment unit (not shown).Wherein, according to embodiments of the invention, described the second compression set 17 is 0.25～0.50MPa for each device is produced contain chlorosilane but containing the tail gas of silane, be not compressed to pressure; Described the 4th condensing works 18 is connected with described the first rectifying purification devices 2 with described the second compression set 17 respectively, for will through overdraft to contain chlorosilane but containing the tail gas of silane, be not cooled to temperature be-15～-30 degrees centigrade, in order to obtain chlorosilane liquid produced and residual gas, and described chlorosilane liquid produced be supplied to described the first rectifying purification devices 2 for described the first rectifying purification process; Described elution device 19 is connected with described the 4th condensing works 18, for described residual gas is carried out to drip washing, in order to obtain gas and the washing water through drip washing; Described washing water treatment unit is connected with described elution device 19, for utilizing alkali lye, described washing water is neutralized, and carries out press filtration to neutralizing rear liquid, so that in obtaining and water and filter residue.Thus, can effectively to what produce in each device, contain chlorosilane but do not processed containing the tail gas of silane, realize non-pollution discharge, guarantee cleaner production, and realize the cycling and reutilization of tail gas, thereby reach energy-conserving and environment-protective, the purpose reduced costs.

According to embodiments of the invention, can also by pipeline by described and water supply to described elution device 19, for described residual gas is carried out to drip washing.Thus, can by and water carry out recycle, thereby reduce production costs, and realize non-pollution discharge, guarantee cleaner production.

Above part has been described the equipment for the preparation of polysilicon of the present invention in detail, and in order to understand better this equipment, below to this equipment, applicable method is described in detail again.

According to a further aspect in the invention, the invention allows for a kind of method for preparing polysilicon.According to embodiments of the invention, see figures.1.and.2, the method comprises the following steps:

S100: chlorine hydrogenation building-up reactions

At first, make silica flour, hydrogen and be selected from hydrogenchloride and at least one generation chlorine hydrogenation building-up reactions of silicon tetrachloride, in order to obtain the chlorine hydrogenation building-up reactions product that comprises trichlorosilane.Wherein, the chemical reaction that this step relates generally to is:

3SiCl ₄+2H ₂+Si——4SiHCl ₃。

According to embodiments of the invention, the condition of chlorine hydrogenation building-up reactions is not particularly limited.According to concrete examples more of the present invention, can when having nickel-base catalyst or copper-based catalysts, the gaseous mixture that comprises silicon tetrachloride and hydrogen be contacted with silica flour, in order to described chlorine hydrogenation building-up reactions occurs.Thus, can effectively improve the efficiency of chlorine hydrogenation building-up reactions, be conducive to trichlorosilane and generate, and the carrying out of subsequent purification step.Wherein, in the gaseous mixture that comprises silicon tetrachloride and hydrogen, the ratio of silicon tetrachloride and hydrogen is not particularly limited.According to embodiments of the invention, in the described gaseous mixture that comprises silicon tetrachloride and hydrogen, the mol ratio of silicon tetrachloride and hydrogen is 1:2～5.Thus, the efficiency of chlorine hydrogenation building-up reactions significantly improves, and be conducive to trichlorosilane and generate, and the carrying out of subsequent purification step.

According to embodiments of the invention, the preparation method of the gaseous mixture that comprises silicon tetrachloride and hydrogen is not particularly limited.According to some embodiments of the present invention, this gaseous mixture that comprises silicon tetrachloride and hydrogen can obtain through the following steps: silicon tetrachloride liquid is mixed with hydrogen, obtain gas-liquid mixture; Utilize described chlorine hydrogenation building-up reactions product to carry out heat exchange process to described gas-liquid mixture, in order to obtain through the gas-liquid mixture of preheating with through overcooled chlorine hydrogenation building-up reactions product; And utilize resistance heater, the gas-liquid mixture through preheating is heated, in order to obtain the described gaseous mixture that comprises silicon tetrachloride and hydrogen.Thus, can in the situation that power consumption minimumly realize the cooling of chlorine hydrogenation building-up reactions product simultaneously and gas-liquid mixture carried out to preheating, and can effectively obtain the gaseous mixture that comprises silicon tetrachloride and hydrogen, for the chlorine hydrogenation building-up reactions in follow-up circulation is supplied raw materials, thereby can effectively realize energy-conserving and environment-protective, the purpose reduced costs.

In addition, for through overcooled chlorine hydrogenation building-up reactions product, can also be further processed.According to embodiments of the invention, above-mentioned method of the present invention may further include: by described, through overcooled chlorine hydrogenation building-up reactions product, carry out dust removal process; To carry out condensation through the chlorine hydrogenation building-up reactions product of dust removal process, so that difference recover hydrogen and chlorosilane liquid produced, described chlorosilane liquid produced comprises trichlorosilane and silicon tetrachloride; And described chlorosilane liquid produced is used for to described the first rectifying purification process.Thus, after overcooled chlorine hydrogenation building-up reactions product is by above-mentioned processing, can obtain chlorosilane liquid produced and hydrogen, and chlorosilane liquid produced and hydrogen can be supplied to respectively corresponding steps follow-up in polycrystalline silicon preparing process, carry out recycle again, thereby can effectively realize energy-conserving and environment-protective, the purpose reduced costs.And, for reclaiming the hydrogen obtained, according to embodiments of the invention, described hydrogen can be returned for carrying out described chlorine hydrogenation building-up reactions.Thus, hydrogen can be recycled, for chlorine hydrogenation building-up reactions is supplied raw materials, energy-conserving and environment-protective, and can reduce production costs.

According to embodiments of the invention, the temperature and pressure of chlorine hydrogenation building-up reactions is not particularly limited, as long as can effectively be reacted, obtains the chlorine hydrogenation building-up reactions product that comprises trichlorosilane and gets final product.According to some embodiments of the present invention, described chlorine hydrogenation building-up reactions is to carry out at the temperature of 500～550 degrees centigrade.Thus, the efficiency of chlorine hydrogenation building-up reactions is high, and be conducive to trichlorosilane and generate, and the carrying out of subsequent purification step.According to embodiments of the invention, described chlorine hydrogenation building-up reactions is at 500～550 degrees centigrade, under the condition of 1.5～3.5MPa, carries out.Thus, chlorine hydrogenation building-up reactions safety, efficiency are high, and be conducive to trichlorosilane and generate, and the carrying out of subsequent purification step.

In addition, the source of the silicon tetrachloride that chlorine hydrogenation building-up reactions adopts is not particularly limited, and can directly provide, and also can from the reaction product of subsequent step or waste liquid, separate and obtain.According to embodiments of the invention, at least a portion of described silicon tetrachloride obtains by trichlorosilane is carried out to disproportionation reaction.Thus, the silicon tetrachloride be about in the disproportionation reaction product in production of polysilicon technique subsequent step has carried out recycle, thereby can realize energy-conserving and environment-protective, the purpose reduced costs.According to other embodiment of the present invention, in first distillation residual liquid that comprises silicon tetrachloride that can also produce from follow-up the first rectifying purification step, separate and obtain.Thus, can effectively realize producing the cycling and reutilization of waste liquid, thereby reach energy-conserving and environment-protective, the purpose reduced costs.

S200: the first rectifying purification process

Secondly, the chlorine hydrogenation building-up reactions product that comprises trichlorosilane of above-mentioned acquisition is carried out to the first rectifying purification process, in order to obtain trichlorosilane and the first distillation residual liquid.

According to embodiments of the invention, the device that the first rectifying purification process adopts is not particularly limited, as long as can effectively realize that the chlorine hydrogenation building-up reactions product to comprising trichlorosilane carries out purification process.According to some embodiments of the present invention, described the first rectifying purification process is to utilize a plurality of rectifying tower of series connection to carry out, and wherein, in each rectifying tower, for the material that carries out rectification process, is along the axial direction due of described rectifying tower and moves from bottom to top.Thus, can effectively improve the efficiency of rectifying purification process, thereby can obtain highly purified trichlorosilane, be conducive to the carrying out of subsequent step.According to preferred embodiments more of the present invention, described the first rectifying purification process is to utilize the first rectifying tower, Second distillation column and the 3rd rectifying tower of series connection to carry out.Thus, can guarantee suitable production cost and higher rectifying purification efficiency simultaneously, thereby can obtain highly purified trichlorosilane, be conducive to the carrying out of subsequent step.Wherein, the condition of the first rectifying purification process is that the reaction conditions in each rectifying tower is not particularly limited, as long as can from the chlorine hydrogenation building-up reactions product that comprises trichlorosilane, obtain trichlorosilane by effective purifying.According to embodiments of the invention, the rectification temperature of described the first rectifying tower is 60～100 degrees centigrade, and pressure is 0.2MPa, and reflux ratio is 10～50:1; The rectification temperature of described Second distillation column is 100～140 degrees centigrade, and pressure is 0.5MPa, and reflux ratio is 20～50:1; The rectification temperature of described the 3rd rectifying tower is 60～80 degrees centigrade, and pressure is 0.2MPa, and reflux ratio is 20～50:1.Thus, can guarantee safety in production, and power consumption less, production cost is low, the rectifying purification efficiency is high, effective, can purify and obtain purity is the trichlorosilane more than 99%.

The waste liquid that can also produce the first rectifying purification process in addition, i.e. the first distillation residual liquid is further processed.According to embodiments of the invention, further comprise: described the first distillation residual liquid is carried out to the flash distillation processing, in order to obtain silicon tetrachloride gas and solid residue; Described silicon tetrachloride gas is carried out to condensation process, in order to obtain silicon tetrachloride liquid; Described silicon tetrachloride liquid is used for to described chlorine hydrogenation building-up reactions; And described solid residue is carried out to alkali lye hydrolysis neutralizing treatment and press filtration processing successively.Thus, can effectively realize the cycling and reutilization of the first distillation residual liquid, thereby reach energy-conserving and environment-protective, the purpose reduced costs.Wherein, when the first rectifying purification process is while utilizing the first rectifying tower of series connection recited above, Second distillation column and the 3rd rectifying tower to carry out, the first distillation residual liquid is the raffinate that discharge the Second distillation column bottom.

S300: disproportionation reaction

Then, make described trichlorosilane generation disproportionation reaction, in order to obtain the disproportionation reaction product that comprises silicon tetrachloride and silane.Wherein, the chemical reaction that this step relates generally to is: 4SiHCl ₃---SiH ₄+ 3SiCl ₄.

According to embodiments of the invention, the condition of disproportionation reaction is not particularly limited, as long as can carry out safely the disproportionation reaction of trichlorosilane, effectively obtains above-mentioned disproportionation reaction product and gets final product.According to concrete examples more of the present invention, described disproportionation reaction is at 50～80 degrees centigrade, under the condition of 0.2～0.6MPa, carries out.Thus, production safety, and the power consumption less, production cost is low, disproportionation reaction efficiency is high, effective, is conducive to the carrying out of subsequent step.

In addition, the device that carries out disproportionation reaction also is not particularly limited, as long as can guarantee production safety, efficiently.According to embodiments of the invention, described disproportionation reaction is carried out in disproportionation reactor, and described disproportionation reactor may further include: disproportionation reactor body, trichlorosilane opening for feed and disproportionation reaction product discharge port.According to concrete examples more of the present invention, limit the disproportionation reaction space in above-mentioned disproportionation reactor body, and be provided with catalyst layer in described disproportionation reaction space; Described trichlorosilane opening for feed is arranged on the below of described catalyst layer, for to described disproportionation reaction space, supplying with trichlorosilane; Described disproportionation reaction product discharge port is arranged on the top of described catalyst layer, for the formed disproportionation reaction product that comprises silicon tetrachloride and silane is discharged to described disproportionation reactor.Thus, disproportionation reaction efficiency is high, effective, and production safety, power consumption less, cost is low, the carrying out that be conducive to subsequent step.

S400: the second rectifying purification process

Next, described disproportionation reaction product is carried out to the second rectifying purification process, in order to obtain silane gas and silicon tetrachloride.

According to embodiments of the invention, device and the required condition of carrying out the second rectifying purification process are not particularly limited.According to concrete examples more of the present invention, described the second rectifying purification process is carried out in low-temperature fractionating tower, and wherein, the temperature in described low-temperature fractionating tower is-60～-80 degrees centigrade, and pressure is 0.6～1.0MPa, and reflux ratio is 5～20:1.Thus, can guarantee production safety, and the power consumption less, production cost is low, the rectifying purification efficiency is high, effective, is conducive to the carrying out of subsequent step.

Wherein, the silicon tetrachloride raffinate for producing in the second rectifying purification step, can be further processed.According to embodiments of the invention, the silicon tetrachloride raffinate is by processing, and the silicon tetrachloride of acquisition is for described chlorine hydrogenation building-up reactions.Thus, effectively realize the recycle of silicon tetrachloride raffinate, and reduced the dispensing of chlorine hydrogenation building-up reactions raw material, thereby can realize energy-conserving and environment-protective, the purpose reduced costs.

S500: pyrolytic reaction

Then, make the silane gas of above-mentioned acquisition that pyrolytic reaction occur in reduction furnace, wherein, be provided with the carrier of silicon core as crystal deposition in described reduction furnace, in order to obtain polysilicon.Wherein, the chemical reaction that this step relates generally to is: SiH ₄---Si+2H ₂.

According to embodiments of the invention, the described silane gas obtained in previous step is stored with the liquid form collection, and, before in entering reduction furnace, pyrolytic reaction occurring, in advance the silane of described liquid form is carried out in vaporizer to vaporization process.Thus, be convenient to the transportation of silane gas, and be conducive to pyrolytic reaction and carry out, and then can effectively prepare polysilicon, and cost is low, need to lack, energy-conserving and environment-protective, and pyrolytic reaction efficiency is high.

According to embodiments of the invention, the type of the reduction furnace that pyrolytic reaction can adopt is not particularly limited.According to concrete examples more of the present invention, described reduction furnace is the bell-jar reduction furnace.Thus, pyrolytic reaction efficiency is high, effective, and the electronic-grade polycrystalline silicon purity prepared is high.

In addition, temperature, pressure condition in reduction furnace in the quantity of silicon rod and reduction furnace also are not particularly limited, as long as be conducive to pyrolytic reaction.According to embodiments of the invention, be provided with 12,24 or 36 pairs of silicon rods in described reduction furnace.Thus, can adopt the silicon core as carrier.Further, according to embodiments of the invention, also be provided with the cooling jacket consistent with silicon core logarithm in reduction furnace.Thereby, be conducive to silane gas checking solution deposition, prepare high-purity electronic-grade polycrystalline silicon.According to other embodiment of the present invention, the temperature in described reduction furnace is 750～900 degrees centigrade, and pressure is 0.15～0.30MPa.Thus, pyrolytic reaction efficiency is high, effective, and reaction safety, and the electronic-grade polycrystalline silicon purity prepared is high.

Wherein, the reduction tail gas produced in pyrolytic reaction can also be further processed, in order to carry out recycle, wherein, the method that reduction tail gas is processed is not particularly limited.According to embodiments of the invention, may further include: it is 6.0～10.0MPa that the reduction tail gas of pyrolytic reaction is compressed to pressure; To be-100～-120 degrees centigrade through reduction tail gas condensing to the temperature of overdraft, in order to silane gas is condensed into to silane liquid, and obtain hydrogen; And described hydrogen is used for to described chlorine hydrogenation building-up reactions.Thus, can effectively to reduction tail gas, be processed, be realized non-pollution discharge, guarantee cleaner production, and realize the cycling and reutilization of reduction tail gas, thereby reach energy-conserving and environment-protective, the purpose reduced costs.

In addition, to what produce in each step, contain chlorosilane but also can not be further processed containing the tail gas of silane, in order to carry out cycling and reutilization, wherein, the method for being processed is not particularly limited.According to embodiments of the invention, may further include: by each step, produce to contain chlorosilane but containing the tail gas of silane, be not compressed to pressure be 0.25～0.50MPa, and further be cooled to the temperature of-15～-30 degrees centigrade, in order to obtain chlorosilane liquid produced and residual gas; Described chlorosilane liquid produced is carried out to described the first rectifying purification process; Described residual gas is carried out to drip washing, in order to obtain gas and washing water through drip washing; And utilize alkali lye to be neutralized described washing water, carry out press filtration to neutralizing rear liquid, so that in obtaining and water and filter residue.Thus, can effectively to what produce in each step, contain chlorosilane but do not processed containing the tail gas of silane, realize non-pollution discharge, guarantee cleaner production, and realize the cycling and reutilization of tail gas, thereby reach energy-conserving and environment-protective, the purpose reduced costs.Wherein, above-mentioned in and water also can be recycled, according to embodiments of the invention, will be in described and water be used for described residual gas is carried out to drip washing.Thus, can by and water carry out recycle, thereby reduce production costs, and realize non-pollution discharge, guarantee cleaner production.

According to other embodiment of the present invention, the polysilicon method for preparing of the present invention can further include: by separating the silicon tetrachloride obtained in intermediate steps, return to S100(chlorine hydrogenation building-up reactions), make it participate in chlorine hydrogenation building-up reactions, and then enter in the processing step of the method for preparing polysilicon of the present invention, carry out sequential loop.Thus, can realize the production purpose of economy, environmental protection.

The contriver is surprised to find, utilize the polysilicon method for preparing of the present invention can effectively prepare electronic-grade polycrystalline silicon, and the method technique is simple, safety, energy-conserving and environment-protective, cost are low, and the polysilicon purity of producing is high, the tail gas produced and waste residue can meet the requirement of environmental protections, are the electronic-grade polycrystalline silicon process for cleanly preparing.

In addition, according to some embodiments of the present invention, with reference to Fig. 2, the polysilicon method for preparing of the present invention can also comprise the following steps:

(a) chlorine hydrogenation synthesis step: adopting silica flour, hydrogen and supplementary silicon tetrachloride (or hydrogenchloride) is raw material with the silicon tetrachloride that comes from subsequent step (b), (c), control temperature 500～550 degree, pressure 1.5～3.5MPa, silicon tetrachloride and hydrogen proportioning 1:2～1:5, under Ni-based or copper-base catalyst effect, in fixed bed (or fluidized-bed) hydrogenation reactor, by converting silicon tetrachloride, be trichlorosilane, for step (c) provides the trichlorosilane raw material.Main reaction is: 3SiCl ₄+ 2H ₂+ Si---4SiHCl ₃.

(b) trichlorosilane rectification and purification step: the chlorosilane mixed solution that comes from step (a) enters in three rectifying tower of series connection, controls 60～100 ℃ of the first rectifying tower temperature, pressure 0.2MPa, reflux ratio 10:1～50:1; Control 100～140 ℃ of Second distillation column temperature, pressure 0.5MPa, reflux ratio 20:1～50:1; Control 60～80 ℃ of the 3rd rectifying tower temperature, pressure 0.2MPa, reflux ratio 20:1～50:1.Obtaining purity is the trichlorosilane more than 99%, and silicon tetrachloride returns to step (a).

(c) trichlorosilane disproportionation step: come from the trichlorosilane of step (b), pass in disproportionation reactor, under catalyst action, control 50～80 ℃ of reactor temperatures, pressure 0.2～0.6MPa, make trichlorosilane be converted into silane gas.The principal reaction equation is: 4SiHCl ₃---SiH ₄+ 3SiCl ₄.

(d) silane gas low temperature fractionation step: come from the silane gas that contains impurity of step (c), enter in low-temperature fractionating tower, temperature-60 in control tower～-80 ℃, pressure 0.60～1.0MPa, reflux ratio 5:1～20:1.Thereby the silane purity of overhead extraction can reach 9N～11N, has mainly removed the impurity compounds such as B, P, Al, C.This part silane gas is with the extraction of liquid mode storage.

(e) silane gas Pintsch process prepares the polysilicon step: the silane gas from step (d) enters in the bell-jar reduction furnace, control 750～900 ℃ of internal temperatures, 0.15MPa～0.30MPa, be deposited on the silicon core silane gas cracking, the hydrogen of generation is back to step (a) recycle.Cracking transformation efficiency of silane gas can reach more than 90%.The principal reaction equation is: SiH ₄---Si+2H ₂.

(f) raffinate recycling step: be that the raffinate that discharge the Second distillation column bottom mainly is rich in silicon tetrachloride and a small amount of solid residue from the first distillation residual liquid produced in step (b), by it after flash distillation, dedusting and condensation etc. are processed, silicon tetrachloride is reclaimed, and solid residue drains into step (h) and processes.

(g) tail gas recycle step: mainly process two portions tail gas, the tail gas that is rich in chlorosilane that a part is discharged for step (a) and (b), (c), (f), after the overdraft deep cooling, after being separated, reclaimed to step (b) most of chlorosilane, contain on a small quantity the tail gas of chlorosilane after tail gas eluting column hydrolysis treatment is qualified, be disposed in atmosphere, and hydrolysis residue to step (h) is processed; Another part is the reduction tail gas from step (e), this partial tail gas contains hydrogen and silane gas, after the overdraft deep cooling, hydrogen is separated and is supplied to step (a) recycle, silane gas be condensed into liquid after overflash to step (e) recycle.

(h) residue neutralization procedure: by the aforementioned solid residue of step (f) and the hydrolysis residue of step (g) of coming from, interpolation neutralizing agent (calcium hydroxide alkali lye) is neutralized, press filtration is processed, then qualified solid slag is carried out to environment protection emission, and waste water is back to the recycle of the described tail gas eluting column of step (g).

Below by specific embodiment, the present invention will be described, it should be noted that these embodiment are only for illustration purpose, and can not be construed to by any way limitation of the present invention.In addition, in the following example, if not otherwise specified, the equipment that adopted and material are commercially available.

Embodiment 1

Utilize the equipment shown in Fig. 3-Figure 12, the flow process shown in seeing figures.1.and.2 according to the method for the preparation of polysilicon of the present invention, prepares trichlorosilane according to following process, and then prepares polysilicon:

(1) chlorine hydrogenation synthesis step: from the silicon tetrachloride of following step (2), step (3) with hydrogen after the gas liquid mixer proportioning is mixed, with the heat exchange of hydrogenation reactor exit gas process, enter resistive heater heats to certain temperature, this mixed gas directly enters in hydrogenation reactor, control temperature 500～550 degree, pressure 1.5～3.5MPa, silicon tetrachloride and hydrogen proportioning 1:2～1:5, under Ni-based or copper-base catalyst effect, with silica flour, react.Reacted gas after efficient gas-solid fly-ash separator in gas-gas heat exchanger with from the gas converting heat of gas liquid mixer, reactant gases after cooling enters the bubbling gas wash tower, to after the further dedusting of solid dust, enter integrated condenser, chlorosilane condensate enters liquid collection tank, and Hydrogen Separation out compressed machine enters the gas liquid mixer recycle.

(2) chlorosilane purification step: utilize the difference of trichlorosilane and silicon tetrachloride boiling point, the principle of different volatility is arranged at the same temperature, adopt three towers (being rectifying tower) purify trichlorosilane.Raffinate is discharged from Second distillation column, and the TCS that process is purified is from the 3rd rectifying tower top extraction, and the STC of recovery discharges and is back to the gas liquid mixer step (1) from the 3rd rectifier bottoms.Obtaining purity is the trichlorosilane more than 99%.

(3) trichlorosilane disproportionation step: 50～80 ℃ of the temperature of control disproportionation reactor, pressure 0.2～0.6MPa, under catalyst action, pass into the TCS of the 3rd rectifying tower top extraction in reactor, and disproportionation reaction occurs, and produces silane gas.

(4) silane gas low temperature fractionation step: utilize the difference of impurity, chlorosilane and the silane gas boiling points such as B, P, C, the principle of different volatility is arranged at the same temperature, adopt low-temperature fractionating tower purification silane gas.The silane gas that comes from step (3) enters low-temperature fractionating tower, temperature-60 in control tower～-80 ℃, pressure 0.60～1.0MPa, reflux ratio 5:1～20:1.Can reach 9N-11N from the silane purity of overhead extraction, mainly remove the impurity compounds such as B, P, Al, C.Go step (5) from the high purity silane gas of overhead extraction, impurity etc. are discharged at the bottom of tower.

(5) silane gas high temperature pyrolysis step: the high purity silane gas from step (4) enters vaporizer, is vaporizated into gas and enters the bell-jar reduction furnace, and inside arranges the carrier of silicon core as crystal deposition, can be 12 pairs of rods, 24 pairs of rods or 36 pairs of excellent reduction furnaces.Control 750～900 ℃ of internal temperatures, under 0.15MPa～0.30MPa, the silane gas cracking is deposited on the silicon core, generates bar-shaped electronic-grade polycrystalline silicon.Being back to step (7) after the reduction tail gas recycle produced processes.Wherein, cracking transformation efficiency of silane gas can reach more than 90%.

(6) raffinate recycling step: the raffinate of discharging from step (2) the 3rd rectifier bottoms, be rich in silicon tetrachloride and a small amount of solid residue, through the flash tank evaporation, flash tank is with whipping appts, axle and body adopt mechanical seal, and its outside is steam jacket, adopt steam heating.The silicon tetrachloride gas be evaporated from flash tank enters follow-up water cooler condensation, and silicon tetrachloride liquid is back to gas liquid mixer in step (1).Solid residue through with alkali lye hydrolysis neutralization by press filtration be harmless in and slag discharge.

(7) tail gas recycle step: whole system is divided into two strands of tail gas.The tail gas of tail gas 1 for containing chlorosilane, wherein containing silane gas.This partial tail gas is through compressor compresses to 0.25～0.50MPa, enter deep freezer, control cryogenic temperature-15～-30 ℃, chlorosilane condensate gets off to be back to step (2), the uncooled gas got off enters the tail gas eluting column, and the qualified gas emptying after drip washing, in washing water and alkali lye and rear press filtration, filter residue effluxes, and Zhong Heshui returns to the eluting column recycle; Tail gas 2 is for being rich in the gas of hydrogen and a small amount of silane gas, the i.e. reduction tail gas out from the bell-jar reduction furnace, this portion gas is through compressor compresses to 6.0～10.0MPa, enter deep freezer and be condensed to-100～-120 ℃, silane gas is condensed into liquid and enters vaporizer, and Hydrogen Separation out enters chlorine hydrogenation synthetic reaction device.

In the description of this specification sheets, the description of reference term " embodiment ", " some embodiment ", " example ", " concrete example " or " some examples " etc. means to be contained at least one embodiment of the present invention or example in conjunction with specific features, structure, material or the characteristics of this embodiment or example description.In this manual, the schematic statement of above-mentioned term not necessarily referred to identical embodiment or example.And the specific features of description, structure, material or characteristics can be with suitable mode combinations in any one or more embodiment or example.

Although illustrated and described embodiments of the invention, those having ordinary skill in the art will appreciate that: in the situation that do not break away from principle of the present invention and aim can be carried out multiple variation, modification, replacement and modification to these embodiment, scope of the present invention is limited by claim and equivalent thereof.

Claims

1. the equipment for the preparation of trichlorosilane, is characterized in that, comprising:

Chlorine hydrogenation synthetic reaction device, described chlorine hydrogenation synthetic reaction device is for making silica flour, hydrogen and being selected from hydrogenchloride and at least one generation chlorine hydrogenation building-up reactions of silicon tetrachloride, in order to obtain the chlorine hydrogenation building-up reactions product that comprises trichlorosilane; And

The first rectifying purification devices, described the first rectifying purification devices is connected with described chlorine hydrogenation synthetic reaction device, for the described chlorine hydrogenation building-up reactions product that comprises trichlorosilane is carried out to the first rectifying purification process, in order to obtain trichlorosilane and the first distillation residual liquid.

2. equipment according to claim 1, it is characterized in that, be provided with nickel-base catalyst or copper-based catalysts in described chlorine hydrogenation synthetic reaction device, so that when having nickel-base catalyst or copper-based catalysts, the gaseous mixture that comprises silicon tetrachloride and hydrogen is contacted with silica flour, described chlorine hydrogenation building-up reactions occurs.

3. equipment according to claim 2, is characterized in that, in the described gaseous mixture that comprises silicon tetrachloride and hydrogen, the mol ratio of silicon tetrachloride and hydrogen is 1:2～5.

4. equipment according to claim 2, is characterized in that, described chlorine hydrogenation building-up reactions is to carry out at the temperature of 500～550 degrees centigrade.

5. equipment according to claim 4, is characterized in that, described chlorine hydrogenation building-up reactions is at 500～550 degrees centigrade, under the condition of 1.5～3.5MPa, carries out.

6. equipment according to claim 2, is characterized in that, further comprises:

Liqiud-gas mixing device, described Liqiud-gas mixing device, for silicon tetrachloride liquid is mixed with hydrogen, obtains gas-liquid mixture;

Heat exchanger, described heat exchanger is connected with described chlorine hydrogenation synthetic reaction device with described Liqiud-gas mixing device respectively, for utilizing described chlorine hydrogenation building-up reactions product to carry out heat exchange process to described gas-liquid mixture, in order to obtain through the gas-liquid mixture of preheating with through overcooled chlorine hydrogenation building-up reactions product; And

Resistance heater, described resistance heater is connected with described chlorine hydrogenation synthetic reaction device with described heat exchanger respectively, for the gas-liquid mixture to through preheating, heated, in order to obtain the described gaseous mixture that comprises silicon tetrachloride and hydrogen, and the described gaseous mixture that comprises silicon tetrachloride and hydrogen is supplied to described chlorine hydrogenation synthetic reaction device.

7. equipment according to claim 6, is characterized in that, further comprises:

Cleaning apparatus, described cleaning apparatus is connected with described heat exchanger, in order to carry out dust removal process by described through overcooled chlorine hydrogenation building-up reactions product; And

The first condensing works, described the first condensing works is connected with the first rectifying purification devices with described cleaning apparatus respectively, for carrying out condensation through the chlorine hydrogenation building-up reactions product of dust removal process, so that difference recover hydrogen and chlorosilane liquid produced, described chlorosilane liquid produced comprises trichlorosilane and silicon tetrachloride, and described chlorosilane liquid produced is supplied to described the first rectifying purification devices for described the first rectifying purification process.

8. equipment according to claim 7, is characterized in that, described the first condensing works is connected with described chlorine hydrogenation synthetic reaction device, for described hydrogen being supplied to described chlorine hydrogenation synthetic reaction device.

9. equipment according to claim 1, is characterized in that, described the first rectifying purification devices comprises a plurality of rectifying tower of series connection, and wherein, each rectifying tower all arranges respectively opening for feed and discharge port from bottom to top along the axial direction due of described rectifying tower.

10. equipment according to claim 9, is characterized in that, described the first rectifying purification devices comprises the first rectifying tower, Second distillation column and the 3rd rectifying tower of series connection.

11. equipment according to claim 10, is characterized in that, the rectification temperature of described the first rectifying tower is 60～100 degrees centigrade, and pressure is 0.2MPa, and reflux ratio is 10～50:1; The rectification temperature of described Second distillation column is 100～140 degrees centigrade, and pressure is 0.5MPa, and reflux ratio is 20～50:1; The rectification temperature of described the 3rd rectifying tower is 60～80 degrees centigrade, and pressure is 0.2MPa, and reflux ratio is 20～50:1.

12. equipment according to claim 6, is characterized in that, further comprises:

The disproportionation reaction device, described disproportionation reaction device is connected with described the first rectifying purification devices, for making described trichlorosilane generation disproportionation reaction, in order to obtain the disproportionation reaction product that comprises silicon tetrachloride and silane;

The second rectifying purification devices, described the second rectifying purification devices is connected with described disproportionation reaction device, for described disproportionation reaction product is carried out to the second rectifying purification process, in order to obtain silane gas and silicon tetrachloride; And

The pyrolytic reaction device, described pyrolytic reaction device is connected with described the second rectifying purification devices, for making described silane gas generation pyrolytic reaction, in order to obtain polysilicon.

13. equipment according to claim 12, is characterized in that, at least a portion of described silicon tetrachloride derives from described disproportionation reaction device.

14. equipment according to claim 12, is characterized in that, described the second rectifying purification devices is connected with described chlorine hydrogenation synthesizer, so as by the silicon tetrachloride that obtains in described the second rectifying purification devices for described chlorine hydrogenation building-up reactions.

15. equipment according to claim 12, is characterized in that, in described disproportionation reaction device, described disproportionation reaction is at 50～80 degrees centigrade, under the condition of 0.2～0.6MPa, carries out.

16. equipment according to claim 12, is characterized in that, described disproportionation reaction device is disproportionation reactor, and described disproportionation reactor further comprises:

The disproportionation reactor body, limit the disproportionation reaction space in described disproportionation reactor body, and be provided with catalyst layer in described disproportionation reaction space;

The trichlorosilane opening for feed, described trichlorosilane opening for feed is arranged on the below of described catalyst layer, for to described disproportionation reaction space, supplying with trichlorosilane; And

Disproportionation reaction product discharge port, described disproportionation reaction product discharge port is arranged on the top of described catalyst layer, for the formed disproportionation reaction product that comprises silicon tetrachloride and silane is discharged to described disproportionation reactor.

17. equipment according to claim 12, is characterized in that, described the second rectifying purification devices is low-temperature fractionating tower, and wherein, the temperature in described low-temperature fractionating tower is-60～-80 degrees centigrade, and pressure is 0.6～1.0MPa, and reflux ratio is 5～20:1.

18. equipment according to claim 12, it is characterized in that, further comprise the vaporization process device, described vaporization process device is connected with described pyrolytic reaction device with described the second rectifying purification devices respectively, for before pyrolytic reaction, the silane gas that will store with liquid form in advance carries out vaporization process.

19. equipment according to claim 12, is characterized in that, described pyrolytic reaction device is reduction furnace, is provided with the carrier of silicon core as crystal deposition in described reduction furnace.

20. equipment according to claim 19, is characterized in that, described reduction furnace is the bell-jar reduction furnace.

21. equipment according to claim 20, is characterized in that, is provided with 12,24 or 36 pairs of silicon rods in described reduction furnace.

22. equipment according to claim 20, is characterized in that, the temperature in described reduction furnace is 750～900 degrees centigrade, and pressure is 0.15～0.30MPa.

23. equipment according to claim 6, is characterized in that, further comprises:

The flash distillation treatment unit, described flash distillation treatment unit is connected with described the first rectifying purification devices, for described the first distillation residual liquid is carried out to the flash distillation processing, in order to obtain silicon tetrachloride gas and solid residue;

The second condensing works, described the second condensing works is connected with described Liqiud-gas mixing device with described flash distillation treatment unit respectively, for described silicon tetrachloride gas is carried out to condensation process, so that acquisition silicon tetrachloride liquid, and described silicon tetrachloride liquid is supplied to described Liqiud-gas mixing device, for described chlorine hydrogenation building-up reactions; And

The residue treatment device, described residue treatment device is connected with described flash distillation treatment unit, for described solid residue being carried out successively to alkali lye hydrolysis neutralizing treatment and press filtration, processes.

24. equipment according to claim 18, is characterized in that, further comprises:

The first compression set, described the first compression set is connected with described pyrolytic reaction device, and being compressed to pressure for the reduction tail gas by pyrolytic reaction is 6.0～10.0MPa; And

The 3rd condensing works, described the 3rd condensing works is connected with described the first compression set, described Liqiud-gas mixing device and described vaporization process device, being used for to be-100～-120 degrees centigrade through reduction tail gas condensing to the temperature of overdraft, in order to silane gas is condensed into to silane liquid and obtains hydrogen, and by described silane liquid supply to described vaporization process device, described hydrogen is supplied to described Liqiud-gas mixing device, for described chlorine hydrogenation building-up reactions.

25. equipment according to claim 12, is characterized in that, further comprises:

The second compression set, described the second compression set is 0.25～0.50MPa for each device is produced contain chlorosilane but containing the tail gas of silane, be not compressed to pressure;

The 4th condensing works, described the 4th condensing works is connected with described the first rectifying purification devices with described the second compression set respectively, for will through overdraft to contain chlorosilane but containing the tail gas of silane, be not cooled to temperature be-15～-30 degrees centigrade, in order to obtain chlorosilane liquid produced and residual gas, and described chlorosilane liquid produced be supplied to described the first rectifying purification devices for described the first rectifying purification process;

Elution device, described elution device is connected with described the 4th condensing works, for described residual gas is carried out to drip washing, in order to obtain gas and the washing water through drip washing; And

The washing water treatment unit, described washing water treatment unit is connected with described elution device, for utilizing alkali lye, described washing water is neutralized, and carries out press filtration to neutralizing rear liquid, so that in obtaining and water and filter residue.

26. equipment according to claim 25, is characterized in that, by described and water supply to described elution device, for described residual gas is carried out to drip washing.