CN105174265B - recovery system and recovery method - Google Patents
recovery system and recovery method Download PDFInfo
- Publication number
- CN105174265B CN105174265B CN201510527559.4A CN201510527559A CN105174265B CN 105174265 B CN105174265 B CN 105174265B CN 201510527559 A CN201510527559 A CN 201510527559A CN 105174265 B CN105174265 B CN 105174265B
- Authority
- CN
- China
- Prior art keywords
- desorption
- gas
- unit
- hydrogen
- recovery system
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Abstract
The invention provides a kind of recovery system and recovery method.The recovery system includes：Condensing unit, reduction tail gas is by obtaining on-condensible gas and condensed liquid after condensing unit, and the outlet of condensing unit is connected with on-condensible gas output channel and condensed liquid output channel；Adsorption desorption unit, it is connected with on-condensible gas output channel, adsorption desorption unit is used to come out the Hydrogen Separation in on-condensible gas, on-condensible gas obtains desorption gas after absorption and desorption occurs by adsorption desorption unit, and the outlet of adsorption desorption unit is connected with hydrogen output channel and desorption gas output channel, and hydrogen output channel is connected to the entrance of polycrystalline silicon reduction system, desorption gas output channel is connected to the entrance of hydrogenation of silicon tetrachloride system.The frequent heating-cooling of liquid chlorosilane material is avoided using above-mentioned recovery system, reduces the consumption of hot and cold amount in Dry recovery system, avoids its condensing unit waste cold for returning to recovery system, while it also avoid the enrichment of impurity.
Description
Technical field
The present invention relates to technical field prepared by polysilicon, in particular to a kind of recovery system and recovery method.
Background technology
The hydrogen reduction of improved Siemens trichlorosilane produces polysilicon process, and reaction conversion ratio is 10% or so, unreacted
Hydrogen, trichlorosilane and byproduct of reaction silicon tetrachloride, hydrogen chloride, dichlorosilane collectively constitute reduction tail gas, into dry
The separation of method recovery system, recovery.Traditional Dry recovery system is by " condensation separation chlorosilane-absorption desorption separating hydrogen chloride-suction
Attached Recovery Purifying hydrogen " three parts form.Concrete technology is condensed with recovering liquid chlorosilane for reduction tail gas is first pressurized, then is led to
The mode for crossing low temperature chlorosilane absorption-high temperature desorption separates and recovers hydrogen chloride most in fixed gas, after through activated carbon
Absorption wherein minimal amount of chlorosilane, hydrogen chloride and other impurity, the overwhelming majority recovery hydrogen after absorption return to silicon tetrachloride
Hydrogenation system, least a portion of recovery hydrogen by the chlorosilane of charcoal absorption and chlorination hydrogen desorption, mix as blowback air after desorption
Gas is back to the condensation procedure of Dry recovery system, and the hydrogen chloride isolated delivers to hydrogenation of silicon tetrachloride system and participates in reaction.
But in the production of actual polysilicon, reduce the chlorine silicon that substantial amounts of hydrogen chloride in tail gas is easily soluble in cryogenic condensation
In alkane lime set, the chlorination hydrogen amount of such Dry recovery system recovery is seldom, and liquid chlorosilanes material is also created for this
Frequently cooling and heating, so as to cause hot and cold amount consumption all very big.Meanwhile it is desorbed to remove in the desorption gas of adsorption column and contains chlorine
Outside silane and hydrogen chloride, the also impurity such as the boron containing trace, phosphorus, nitrogen, oxygen, carbon, gas returns to dry method system, impurity one after desorption
The directly circulation collection in hydrogen, so as to also influence the quality of product high purity polycrystalline silicon.
The content of the invention
It is a primary object of the present invention to provide a kind of recovery system and recovery method, to improve the polysilicon produced
Purity and quality.
To achieve these goals, according to an aspect of the invention, there is provided a kind of recovery system, for reclaiming polycrystalline
Reduction tail gas caused by Si reduction system, polycrystalline silicon reduction system and hydrogenation of silicon tetrachloride system connectivity, it is characterised in that recovery
System includes：Condensing unit, reduction tail gas is by obtaining on-condensible gas and condensed liquid after condensing unit, and condensing unit
Outlet is connected with on-condensible gas output channel and condensed liquid output channel；Adsorption desorption unit, with on-condensible gas output channel
Connection, adsorption desorption unit are used to come out the Hydrogen Separation in on-condensible gas, and on-condensible gas is adsorbed by adsorption desorption unit
With desorption gas is obtained after desorption, and the outlet of adsorption desorption unit is connected with hydrogen output channel and desorption gas output channel,
And hydrogen output channel is connected to the entrance of polycrystalline silicon reduction system, desorption gas output channel is connected to hydrogenation of silicon tetrachloride system
The entrance of system.
Further, recovery system also includes：Desorption unit, it is connected with condensed liquid output channel, condensed liquid
Gas after desorption by obtaining component including hydrogen chloride after desorption unit；Tail gas treating unit, it is connected to going out for desorption unit
Mouthful, for gas after desorption to be condensed and purified to obtain including tail gas after the condensation of hydrogen chloride；Crystalline element, it is connected to
The outlet of tail gas treating unit, including neutralization chamber and vaporising device, the alkali lye in hydrogen chloride and neutralization chamber after condensation in tail gas
Reaction generation chloride solution, and chloride solution be evaporated by vaporising device after obtain chloride crystallization body.
Further, desorption unit includes low pressure chlorosilane basin and/or chlorosilane separating-purifying tower.
Further, reduction tail gas includes hydrogen, hydrogen chloride, chlorosilane and boron and phosphorus matter, desorption gas including hydrogen chloride,
Chlorosilane and boron and phosphorus matter.
According to another aspect of the present invention, there is provided a kind of recovery method, utilize returning for any one of Claims 1-4 4
Reduction tail gas, polycrystalline silicon reduction system and hydrogenation of silicon tetrachloride system connectivity caused by receipts system recovery polycrystalline silicon reduction system,
Recovery method includes：Step S1, the condensing unit being passed through reduction tail gas in recovery system, obtains liquid after on-condensible gas and condensation
Body；Step S2, the adsorption desorption unit being passed through on-condensible gas in recovery system carries out adsorption desorption processing, by on-condensible gas
Hydrogen Separation comes out, and on-condensible gas after adsorption desorption unit progress adsorption treatment and desorption processing by obtaining desorption gas；Step
Rapid S3, the hydrogen separated by adsorption desorption unit is passed through in polycrystalline silicon reduction system, and desorption gas is passed through four chlorinations
In silicon hydrogenation system.
Further, recovery system is the recovery system of claim 2；Recovery method also includes：Step S4, after condensing
Liquid is passed into desorption unit, obtains gas after desorption of the component including hydrogen chloride；Step S5, gas after desorption is passed through tail
Condensation process is carried out in gas disposal unit to obtain including tail gas after the condensation of hydrogen chloride；Step S6, tail gas after condensation is passed through
In neutralization chamber, make the alkaline reaction generation chloride solution in the hydrogen chloride and neutralization chamber after condensation in tail gas, and reclaim neutralization
The supernatant of groove, the chloride crystallization in supernatant is made by vaporising device.
Further, recovery system is the recovery system of claim 3；The step of obtaining gas after desorption includes：Will be cold
Liquid is passed through low pressure chlorosilane basin after solidifying, to isolate gas after desorption from condensed liquid；And/or by condensed liquid
It is passed through chlorosilane separating-purifying tower to be purified, gas after desorption is formed at the top of purifying column.
Further, in step sl, by carrying out low pressure condensation process and high pressure condensation process to reduction tail gas, obtain
On-condensible gas and condensed liquid；In step s3, after carrying out pressurized treatments to desorption gas, it is passed through hydrogenation of silicon tetrachloride system
In.
Further, in step sl, the gauge pressure of low pressure condensation process is 0.4~0.6MPaG, low pressure condensation process temperature
Spend for -5~-30 DEG C, the gauge pressure of high pressure condensation process is 1.0~1.2MPaG, and the temperature of high pressure condensation process is -45~-35
℃；In step s 2, the gauge pressure of adsorption treatment is 1.0~1.2MPaG, and the temperature of adsorption treatment is 15~40 DEG C, desorption processing
Gauge pressure be 0.03~0.06MPaG, be desorbed processing temperature be 100~130 DEG C；In step s3, the gauge pressure of pressurized treatments is
1.9~3.0MPaG.
Further, in step s 5, the gauge pressure of condensation process is 0.3~0.6MPaG, and the temperature of condensation process is -15
~-30 DEG C；In step s 6, alkali lye is the calcium hydroxide that mass concentration is 5~25%.
Apply the technical scheme of the present invention, the invention provides a kind of recovery system, the recovery system includes condensing unit
With adsorption desorption unit, because adsorption desorption unit is connected with condensing unit by on-condensible gas output channel, adsorption desorption unit passes through
Hydrogen output channel is connected with polycrystalline silicon reduction system, and adsorption desorption unit also passes through desorption gas output channel and silicon tetrachloride
Hydrogenation system connects, so as to eliminate the process of hydrogen chloride low temperature absorption-high temperature desorption in the Dry recovery system of prior art,
The frequent heating-cooling of liquid chlorosilane material is avoided, reduces the consumption of hot and cold amount in Dry recovery system；Also, due to
Hydrogen chloride in fixed gas caused by condensing unit is present in desorption gas and enters hydrogenation of silicon tetrachloride system, so as to avoid
It returns to the condensing unit of recovery system and wastes cold, while it also avoid reducing tail gas in polycrystalline silicon reduction system and recovery
Closed cycle between system and caused by impurity enriched, and then improve the purity and quality of the polysilicon produced.
Brief description of the drawings
The Figure of description for forming the part of the application is used for providing a further understanding of the present invention, and of the invention shows
Meaning property embodiment and its illustrate be used for explain the present invention, do not form inappropriate limitation of the present invention.In the accompanying drawings：
Fig. 1 shows the recovery system that embodiment of the present invention is provided, and recovery system is connected with polycrystalline reduction system
System and the schematic diagram of hydrogenation of silicon tetrachloride system；And
Fig. 2 shows the schematic flow sheet for the recovery method that embodiment of the present invention is provided.
Embodiment
It should be noted that in the case where not conflicting, the feature in embodiment and embodiment in the application can phase
Mutually combination.Describe the present invention in detail below with reference to the accompanying drawings and in conjunction with the embodiments.
It should be noted that term used herein above is merely to describe embodiment, and be not intended to restricted root
According to the illustrative embodiments of the present invention.As used herein, unless the context clearly indicates otherwise, otherwise singulative
It is also intended to include plural form, additionally, it should be understood that, when in this manual using term "comprising" and/or " bag
Include " when, it indicates existing characteristics, step, operation, device, component and/or combinations thereof.
For the ease of description, space relative terms can be used herein, as " ... on ", " ... top ",
" ... upper surface ", " above " etc., for describing such as a device shown in the figure or feature and other devices or spy
The spatial relation of sign.It should be appreciated that space relative terms are intended to comprising the orientation except device described in figure
Outside different azimuth in use or operation.For example, if the device in accompanying drawing is squeezed, it is described as " in other devices
It will be positioned as " under other devices or construction after the device of part or construction top " or " on other devices or construction "
Side " or " under other devices or construction ".Thus, exemplary term " ... top " can include " ... top " and
" in ... lower section " two kinds of orientation.The device can also other different modes positioning (being rotated by 90 ° or in other orientation), and
And respective explanations are made to the relative description in space used herein above.
As described in background technology, in the production of actual polysilicon, the hydrogen chloride of Dry recovery system recovery
Amount is seldom, and hot and cold amount consumption is all very big, and the circulation collection in hydrogen always of the impurity in desorption gas, so as to also influence production
The quality of product high purity polycrystalline silicon.The present inventor is studied regarding to the issue above, it is proposed that a kind of recovery system, is used for
Reduction tail gas, polycrystalline silicon reduction system 30 caused by polycrystalline silicon reduction system 30 is reclaimed to connect with hydrogenation of silicon tetrachloride system 20,
Its structure is as shown in figure 1, the recovery system 10 includes：Condensing unit 110, reduction tail gas after condensing unit 110 by obtaining not
Solidifying gas and condensed liquid, and the outlet of condensing unit 110 is connected with on-condensible gas output channel and condensed liquid output
Pipeline；Adsorption desorption unit 120, it is connected with on-condensible gas output channel, adsorption desorption unit 120 is used for the hydrogen in on-condensible gas
Separate, on-condensible gas obtains desorption gas, and adsorption desorption unit after absorption and desorption occurs by adsorption desorption unit 120
120 outlet is connected with hydrogen output channel 122 and desorption gas output channel 121, and hydrogen output channel 122 be connected to it is more
The entrance of crystal silicon also original system 30, desorption gas output channel 121 are connected to the entrance of hydrogenation of silicon tetrachloride system 20.
Because adsorption desorption unit is connected with condensing unit by on-condensible gas output channel in above-mentioned recovery system, adsorption desorption
Unit is connected by hydrogen output channel with polycrystalline silicon reduction system, and adsorption desorption unit also by desorption gas output channel with
Hydrogenation of silicon tetrachloride system connects, and is taken off so as to eliminate hydrogen chloride low temperature absorption-high temperature in the Dry recovery system of prior art
The process of suction, the frequent heating-cooling of liquid chlorosilane material is avoided, reduces the consumption of hot and cold amount in Dry recovery system；
Also, because the hydrogen chloride in fixed gas caused by condensing unit is present in desorption gas and enters hydrogenation of silicon tetrachloride system
System, so as to avoid the condensing unit waste cold that it returns to recovery system, while it also avoid reducing tail gas in polysilicon also
Closed cycle between original system and recovery system and caused by impurity enriched, and then improve the polysilicon produced purity and
Quality.
Above-mentioned condensed liquid includes liquid chlorosilane and is dissolved in the hydrogen chloride of liquid chlorosilane；Wrapped in above-mentioned on-condensible gas
The impurity such as hydrogen and hydrogen chloride, chlorosilane and boron phosphorus are included, and above-mentioned on-condensible gas is inhaled by the adsorbent in adsorption desorption unit 120
Attached to obtain pure recovery hydrogen, most of hydrogen that reclaims is back to polycrystalline silicon reduction system 30, and small part recovery hydrogen is used
In pulse cleaning adsorbent, adsorbent hydrogen chloride, chlorosilane and boron and phosphorus matter etc. are desorbed, to form above-mentioned desorption
Gas.
In the above-mentioned recovery system of the present invention, recovery system 10 can also include：Desorption unit 130, with condensed liquid
Output channel connects, gas after desorption of the condensed liquid by obtaining component including hydrogen chloride after desorption unit 130；At tail gas
Unit 140 is managed, the outlet of desorption unit 130 is connected to, for being condensed gas after desorption to reclaim chlorosilane liquid produced, obtains
Tail gas after to the condensation of containing hydrogen chloride；Crystalline element 150, it is connected to the outlet of tail gas treating unit 140, including neutralization chamber and steaming
Transmitting apparatus, hydrogen chloride gas and the alkaline reaction generation chloride solution in neutralization chamber, and chloride solution passes through vaporising device
Chloride crystallization body is obtained after being evaporated.
It is preferably carried out above-mentioned in mode, because condensing unit 110 is also connected with desorption unit 130 in turn, at tail gas
Unit 140 and crystalline element 150 are managed, so that passing through desorption unit 130 by the condensed liquid obtained after condensing unit 110
Component is obtained as gas after the desorption of hydrogen chloride, and gas after desorption is entered by tail gas treating unit 140 to gas after desorption
Tail gas after condensation is passed through crystalline element 150 by row condensation and purification to obtain including tail gas after the condensation of hydrogen chloride, will condensation
The hydrogen chloride in tail gas carries out neutralization reaction afterwards and evaporative crystallization obtains chloride crystallization product, and above-mentioned chloride crystallization product can
To be sold outside as chemical products.Gas including hydrogen chloride except also including nitrogen, hydrogen and chlorosilane, wherein chlorine after above-mentioned desorption
Change hydrogen accounts for gas volume total amount after desorption 5~15%.
In the above-mentioned recovery system of the present invention, the species and composition of desorption unit 130 can be set according to prior art
It is fixed, it is preferable that desorption unit 130 includes low pressure chlorosilane basin 131 and/or chlorosilane separating-purifying tower 132.Dry recovery system
Condensed liquid (including liquid chlorosilane and be dissolved in hydrogen chloride of a liquid chlorosilane) part is obtained during the condensation of system 10 with nitrogen
Desorption comes out hydrogen chloride and enters tail gas treating unit 140 in the low pressure chlorosilane basin 131 of hermetic seal, and another part enters purification
System, enter tail gas treating unit 140 in the form of incoagulable gas in the top hydrogen chloride of chlorosilane separating-purifying tower 132.
In the above-mentioned recovery system of the present invention, the trichlorosilane hydrogen reduction production polysilicon in hydrogenation of silicon tetrachloride system 20
For the reaction conversion ratio of process 10% or so, the reduction tail gas for being passed through recovery system 10 can be above-mentioned hydrogenation of silicon tetrachloride system
Reduction tail gas caused by 20, including unreacted hydrogen, trichlorosilane and byproduct of reaction silicon tetrachloride, hydrogen chloride, dichloro two
Hydrogen silicon and with boron and phosphorus matter etc.；It can include chlorination by obtaining desorption gas after the generation of adsorption desorption unit 120 absorption and desorption
Hydrogen and chlorosilane, further, desorption gas can also include a small amount of hydrogen.Above-mentioned desorption gas passes through attached gas output tube
Road enters hydrogenation of silicon tetrachloride system 20, has the function that hydrogen chloride cycling and reutilization, while avoids it and return to recovery system
10 condensing unit 110 wastes cold.
According to another aspect of the present invention, there is provided a kind of recovery method, as shown in Fig. 2 the recovery method utilizes right
It is required that reduce tail gas, polycrystalline silicon reduction system and four caused by any one of 1 to 4 recovery system recovery polycrystalline silicon producing device
Silicon chloride hydrogenation system connects, and the recovery method includes：Step S1, the condensation list being passed through reduction tail gas in recovery system
Member, obtain on-condensible gas and condensed liquid；Step S2, the adsorption desorption unit that on-condensible gas is passed through in recovery system is inhaled
Desorption processing, the Hydrogen Separation in on-condensible gas is come out, and on-condensible gas by adsorption desorption unit carry out adsorption treatment and
Desorption gas is obtained after desorption processing；Step S3, the hydrogen separated by adsorption desorption unit is passed through polycrystalline silicon reduction system
In, and desorption gas is passed through in hydrogenation of silicon tetrachloride system.
Because above-mentioned recovery method make use of the above-mentioned recovery system of the present invention, and in the recovery system adsorption desorption unit with
Condensing unit is connected by on-condensible gas output channel, and adsorption desorption unit is connected by hydrogen output channel and polycrystalline silicon reduction system
Connect, and adsorption desorption unit is also connected by desorption gas output channel with hydrogenation of silicon tetrachloride system, so as to eliminate existing skill
The process of hydrogen chloride low temperature absorption-high temperature desorption in the Dry recovery system of art, avoid liquid chlorosilane material frequent liter,
Cooling, reduces the consumption of hot and cold amount in Dry recovery system；Also, due to the chlorination in fixed gas caused by condensing unit
Hydrogen is present in desorption gas and enters hydrogenation of silicon tetrachloride system, so as to avoid the condensing unit wave that it returns to recovery system
Take cold, at the same it also avoid reducing closed cycle of the tail gas between polycrystalline silicon reduction system and recovery system and caused by impurity
Enrichment, and then improve the purity and quality of the polysilicon produced.
The illustrative embodiments of the recovery method provided according to the application are provided.However, these
Illustrative embodiments can be implemented by many different forms, and should not be construed to be limited solely to set forth herein
Embodiment.It should be appreciated that these embodiments are provided so that disclosure herein is thoroughly and complete, and will
The design of these illustrative embodiments is fully conveyed to those of ordinary skill in the art.
Tail gas is reduced using caused by above-mentioned recovery system recovery polycrystalline silicon producing device, polycrystalline silicon producing device includes
Hydrogenation of silicon tetrachloride system and polycrystalline silicon reduction system.First, condensing unit reduction tail gas being passed through in recovery system, is obtained
On-condensible gas and condensed liquid.It is further preferable that in above-mentioned steps, by reduction tail gas is carried out low pressure condensation process and
High pressure condensation process, obtains on-condensible gas and condensed liquid.Low pressure condensation process refers to reduction tail gas being passed through compared with low pressure
In the environment of lower temperature, high pressure condensation process then refers to the environment that reduction tail gas is passed through to higher pressure and lower temperature
In.
In above-mentioned preferred embodiment, the gauge pressure of low pressure condensation process can be 0.4~0.6MPaG, low pressure cold
Solidifying treatment temperature can be -5~-30 DEG C；The gauge pressure of high pressure condensation process can be 1.0~1.2MPaG, high pressure condensation process
Temperature can be -45~-35 DEG C.In above-mentioned preferable parameter area, can make to be passed through condensing unit includes trichlorine hydrogen
The reduction tail gas of silicon and silicon tetrachloride is more rapidly and substantially liquefied to form condensed liquid, so as to more efficiently progress
The recovery of liquid chlorosilane, while can will also carry out effectively adsorption desorption and handle.
In the condensing unit for completing reduction tail gas to be passed through in recovery system, obtain the step of on-condensible gas and condensed liquid
After rapid, adsorption desorption unit on-condensible gas being passed through in recovery system carries out adsorption desorption processing, by the hydrogen in on-condensible gas
Gas is separated, and on-condensible gas after adsorption desorption unit generation absorption and desorption by obtaining desorption gas.In above-mentioned steps,
The reduction tail gas for including hydrogen, hydrogen chloride and dichlorosilane not being liquefied forms on-condensible gas, and the on-condensible gas leads to
Enter and adsorption treatment is carried out into adsorption desorption unit, wherein on-condensible gas in addition to hydrogen is tightly held by activated carbon post absorption, so as to
Hydrogen Separation is come out from on-condensible gas, desorption processing is carried out to the on-condensible gas for being tightly held by activated carbon post absorption, so as to shape
Into the desorption gas for including the on-condensible gas for being tightly held by activated carbon post absorption.
In a preferred embodiment, adsorption treatment can be 1.0~1.2MPaG in gauge pressure, and temperature is 15~40
Carried out under conditions of DEG C；Desorption processing can be 0.03~0.06MPaG in gauge pressure, and temperature is to be carried out at 100~130 DEG C.Upper
State in preferable parameter area, can be rapider from the on-condensible gas being passed into adsorption desorption unit and sufficiently isolate hydrogen
Gas, desorption processing is carried out to active carbon adsorption column absorption to form desorption gas so as to more efficiently.
Adsorption desorption processing is carried out in the adsorption desorption unit for completing on-condensible gas being passed through in recovery system, by on-condensible gas
In Hydrogen Separation come out, and on-condensible gas carries out obtaining desorption gas after adsorption treatment and desorption are handled by adsorption desorption unit
The step of after, the hydrogen separated by adsorption desorption unit is passed through in polycrystalline silicon reduction system, and desorption gas is passed through
In hydrogenation of silicon tetrachloride system.In above-mentioned steps, the hydrogen separated by adsorption desorption unit is passed through polycrystalline reduction system
Step in system can carry out effective recycling to the hydrogen in reduction tail gas, i.e., by caused by polycrystalline silicon producing device
Hydrogen in reduction tail gas continues on in the process of production polysilicon, on the other hand, desorption gas is passed through into silicon tetrachloride
The desorption gas that step in hydrogenation system can include hydrogen, hydrogen chloride and chlorosilane participates in four chlorinations as reactant
In the technique of silicon hydrogenation generation trichlorosilane.
In the step of desorption gas is passed through to hydrogenation of silicon tetrachloride system, pressurized treatments first can be carried out to desorption gas
Afterwards, then it is passed through in hydrogenation of silicon tetrachloride system.Pressurized treatments can make desorption gas is more efficiently to be passed into silicon tetrachloride hydrogen
The generation technique of trichlorosilane is participated in change system.Above-mentioned pressurized treatments can be in the process conditions that gauge pressure is 1.9~3.0MPaG
Lower progress.In above-mentioned preferable parameter area, more desorption gas can be made more rapidly to be passed into silicon tetrachloride hydrogen
The generation technique of trichlorosilane is participated in change system.
The step of recovery method for applying providing, is not limited in above-mentioned embodiment.Preferably, the step of recovery method
It can also include：Step S4, condensed liquid is passed into desorption unit, obtains gas after desorption of the component including hydrogen chloride
Body；Step S5, gas after desorption is passed through in tail gas treating unit after carrying out condensation process to obtain including the condensation of hydrogen chloride
Tail gas；Step S6, tail gas after above-mentioned condensation is passed through in neutralization chamber, makes the alkali in the hydrogen chloride and neutralization chamber after condensation in tail gas
Liquid reaction generation chloride solution, and the supernatant of neutralization chamber is reclaimed, the chloride crystallization in supernatant is made by vaporising device.
By carrying out the processing of above-mentioned steps to condensed liquid, the hydrogen chloride in condensed liquid can be made to form chloride crystallization production
Thing, to be sold as product.Wherein, the alkali lye in neutralization chamber can be calcium hydroxide, it is further preferable that the quality of calcium hydroxide
Concentration is 5~25%, now neutralizes generation calcium chloride, finally reclaims the supernatant of neutralization chamber, makes Chlorine in Solution by evaporation
Thing crystallizes, and is sold outside as chemical products.Gas is including hydrogen chloride except also including nitrogen, hydrogen and chlorosilane after above-mentioned desorption,
Wherein hydrogen chloride accounts for 5~15% of gas volume total amount after desorption.
In above-mentioned preferred embodiment, the step of obtaining gas after desorption, can include：Condensed liquid is passed through
Low pressure chlorosilane basin, to isolate gas after the desorption from condensed liquid；And/or condensed liquid is passed through chlorine silicon
Alkane separating-purifying tower carries out purification ＆ isolation chlorosilane, and gas after desorption is formed at the top of purifying column.In above-mentioned steps, after condensation
The hydrogen chloride of liquid chlorosilane is dissolved in liquid can be divided into two parts, low pressure chlorosilane basin of the part in desorption unit
Middle desorption out enters tail gas treating unit, and another part enters the chlorosilane separating-purifying of desorption unit with chlorosilane material
Tower, enter tail gas treating unit in the form of incoagulable gas at the top of purifying column；In tail gas treating unit by condensation and
To reclaim the chlorosilane in condensed liquid, the neutralization chamber entered back into afterwards in crystalline element carries out neutralization reaction with alkali lye for purification
Generate chloride.
It is above-mentioned by desorption after gas be passed through in tail gas treating unit and carry out condensation process to obtain including the cold of hydrogen chloride
After solidifying the step of tail gas in, the gauge pressure of condensation process can be 0.3~0.6MPaG, the temperature of condensation process can for -15~-
30 DEG C, above-mentioned preferable parameter area can make chlorosilane after desorption in gas by more rapidly and sufficiently recovery, so as to return
Chlorosilane liquid produced is received, and then tail gas after the condensation of containing hydrogen chloride is passed into neutralization chamber and efficiently generates chloride.
As can be seen from the above description, the above embodiments of the present invention realize following technique effect：
1st, because adsorption desorption unit is connected with condensing unit by on-condensible gas output channel, so as to eliminate prior art
Dry recovery system in hydrogen chloride low temperature absorption-high temperature desorption process, avoid the frequent ascending, descending of liquid chlorosilane material
Temperature, reduce the consumption of hot and cold amount in Dry recovery system；
2nd, because adsorption desorption unit is connected by hydrogen output channel with polycrystalline silicon reduction system, caused by condensing unit
Hydrogen chloride in fixed gas is present in desorption gas and enters hydrogenation of silicon tetrachloride system, and recovery system is returned so as to avoid it
The condensing unit of system wastes cold, while it also avoid reducing closed circuit between polycrystalline silicon reduction system and recovery system of tail gas and follow
Ring and caused by impurity enriched, and then improve the purity and quality of the polysilicon produced；
3rd, because adsorption desorption unit is connected by desorption gas output channel with hydrogenation of silicon tetrachloride system, and liquid after condensing
Body output channel is connected with desorption unit, tail gas treating unit and crystalline element in turn, so that being dissolved in condensed liquid
Hydrogen chloride can be reclaimed by being converted into the form of chloride crystals, while chlorion in efflux wastewater is also greatly decreased
Content, and then the byproduct hydrogen chloride of polycrystalline silicon reduction system has been obtained comprehensive recovery, utilization, avoid hydrogen chloride material
Loss, there is good economical and environmentally friendly benefit.
The preferred embodiments of the present invention are these are only, are not intended to limit the invention, for those skilled in the art
For member, the present invention can have various modifications and variations.Any modification within the spirit and principles of the invention, being made,
Equivalent substitution, improvement etc., should be included in the scope of the protection.
Claims (8)
- A kind of 1. recovery system, for reclaiming reduction tail gas, the polycrystalline reduction system caused by polycrystalline silicon reduction system (30) System (30) connects with hydrogenation of silicon tetrachloride system (20), it is characterised in that the recovery system (10) includes：Condensing unit (110), the reduction tail gas pass through liquid after on-condensible gas is obtained after the condensing unit (110) and is condensed Body, and the outlet of the condensing unit (110) is connected with on-condensible gas output channel and condensed liquid output channel；Adsorption desorption unit (120), it is connected with the on-condensible gas output channel, the adsorption desorption unit (120) is used for by described in Hydrogen Separation in on-condensible gas comes out, after by the adsorption desorption unit (120) absorption and desorption occur for the on-condensible gas Desorption gas is obtained, and the outlet of the adsorption desorption unit (120) is connected with hydrogen output channel (122) and desorption gas output Pipeline (121), and the hydrogen output channel (122) is connected to the entrance of the polycrystalline silicon reduction system (30), the desorption Gas outlet duct (121) is connected to the entrance of the hydrogenation of silicon tetrachloride system (20),The recovery system (10) also includes：Desorption unit (130), it is connected with the condensed liquid output channel, the condensed liquid passes through the desorption unit (130) gas after the desorption of component including hydrogen chloride is obtained after；Tail gas treating unit (140), the outlet of the desorption unit (130) is connected to, for being carried out to gas after the desorption Condense and purify to obtain including tail gas after the condensation of hydrogen chloride；Crystalline element (150), the outlet of the tail gas treating unit (140), including neutralization chamber and vaporising device are connected to, it is described Hydrogen chloride after condensation in tail gas and the alkaline reaction generation chloride solution in the neutralization chamber, and the chloride solution leads to Pervaporation device obtains chloride crystallization body after being evaporated.
- 2. recovery system according to claim 1, it is characterised in that the desorption unit (130) includes low pressure chlorosilane Basin (131) and/or chlorosilane separating-purifying tower (132).
- 3. recovery system according to claim 1, it is characterised in that the reduction tail gas includes hydrogen, hydrogen chloride, chlorine silicon Alkane and boron and phosphorus matter, the desorption gas include hydrogen chloride, chlorosilane and boron and phosphorus matter.
- 4. a kind of recovery method, it is characterised in that reclaimed using the recovery system (10) any one of claims 1 to 33 Reduction tail gas caused by polycrystalline silicon reduction system (30), the polycrystalline silicon reduction system (30) and hydrogenation of silicon tetrachloride system (20) Connection, the recovery method include：Step S1, the reduction tail gas is passed through condensing unit (110) in the recovery system (10), obtain on-condensible gas and Condensed liquid；Step S2, the adsorption desorption unit (120) that the on-condensible gas is passed through in the recovery system (10) is carried out at adsorption desorption Reason, the Hydrogen Separation in the on-condensible gas is come out, and the on-condensible gas is carried out by the adsorption desorption unit (120) Desorption gas is obtained after adsorption treatment and desorption processing；Step S3, the hydrogen separated by the adsorption desorption unit (120) is passed through in the polycrystalline silicon reduction system (30), And the desorption gas is passed through in the hydrogenation of silicon tetrachloride system (20),The recovery system (10) is the recovery system (10) described in claim 1；The recovery method also includes：Step S4, the condensed liquid is passed into the desorption unit (130), obtaining component includes the desorption of hydrogen chloride Gas afterwards；Step S5, gas after the desorption is passed through in the tail gas treating unit (140) and carries out condensation process to be included Tail gas after the condensation of hydrogen chloride；Step S6, tail gas after the condensation is passed through in the neutralization chamber, makes hydrogen chloride after the condensation in tail gas and described Alkaline reaction generation chloride solution in neutralization chamber, and the supernatant of the neutralization chamber is reclaimed, made by the vaporising device Chloride crystallization in supernatant.
- 5. recovery method according to claim 4, it is characterised in thatThe recovery system (10) is the recovery system (10) described in claim 2；The step of obtaining gas after the desorption includes：The condensed liquid is passed through the low pressure chlorosilane basin (131), to isolate institute from the condensed liquid State gas after desorption；And/orThe condensed liquid is passed through into the chlorosilane separating-purifying tower (132) to be purified, pushed up in the purifying column (132) Portion forms gas after the desorption.
- 6. recovery method according to claim 4, it is characterised in thatIn the step S1, by carrying out low pressure condensation process and high pressure condensation process to the reduction tail gas, obtain described On-condensible gas and the condensed liquid；In the step S3, after carrying out pressurized treatments to the desorption gas, the hydrogenation of silicon tetrachloride system (20) is passed through In.
- 7. recovery method according to claim 6, it is characterised in thatIn the step S1, the gauge pressure of the low pressure condensation process is 0.4~0.6MPaG, described low pressure condensation process temperature Spend for -5~-30 DEG C, the gauge pressure of the high pressure condensation process is 1.0~1.2MPaG, the temperature of the high pressure condensation process for - 45~-35 DEG C；In the step S2, the gauge pressure of the adsorption treatment is 1.0~1.2MPaG, the temperature of the adsorption treatment for 15~ 40 DEG C, the gauge pressure of the desorption processing is 0.03~0.06MPaG, and the temperature of the desorption processing is 100~130 DEG C；In the step S3, the gauge pressure of the pressurized treatments is 1.9~3.0MPaG.
- 8. recovery method according to claim 4, it is characterised in thatIn the step S5, the gauge pressure of the condensation process is 0.3~0.6MPaG, and the temperature of the condensation process is -15 ~-30 DEG C；In the step S6, the alkali lye is the calcium hydroxide that mass concentration is 5~25%.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510527559.4A CN105174265B (en) | 2015-08-25 | 2015-08-25 | recovery system and recovery method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510527559.4A CN105174265B (en) | 2015-08-25 | 2015-08-25 | recovery system and recovery method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN105174265A CN105174265A (en) | 2015-12-23 |
| CN105174265B true CN105174265B (en) | 2018-02-02 |
Family
ID=54896806
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201510527559.4A Active CN105174265B (en) | 2015-08-25 | 2015-08-25 | recovery system and recovery method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN105174265B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111036029B (en) * | 2018-10-15 | 2022-03-04 | 新特能源股份有限公司 | Method for recovering waste gas in polycrystalline silicon production process |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7935327B2 (en) * | 2006-08-30 | 2011-05-03 | Hemlock Semiconductor Corporation | Silicon production with a fluidized bed reactor integrated into a siemens-type process |
| CN101700466B (en) * | 2009-12-11 | 2012-05-02 | 乐山乐电天威硅业科技有限责任公司 | Process for treating residual liquid and tail gas in polysilicon production by improved Siemens method |
| DE102010040293A1 (en) * | 2010-09-06 | 2012-03-08 | Wacker Chemie Ag | Process for producing polycrystalline silicon |
| CN103058140B (en) * | 2013-01-23 | 2015-03-18 | 内蒙古盾安光伏科技有限公司 | Recovery system and recovery method of by-product in polycrystalline silicon production |
| CN205011391U (en) * | 2015-08-25 | 2016-02-03 | 中国恩菲工程技术有限公司 | Recovery system |
-
2015
- 2015-08-25 CN CN201510527559.4A patent/CN105174265B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN105174265A (en) | 2015-12-23 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103848426B (en) | Vacuum falling film method of evaporation is utilized to concentrate the method for silicofluoric acid | |
| CN105036141B (en) | A kind of method of chlorosilane waste gas production nano silicon and by-product hydrochloric acid | |
| WO2023202270A1 (en) | Method for graded utilization of fluorine and silicon resources in phosphate ore | |
| CN104030293B (en) | A kind of silicon tetrachloride purifying technique and system | |
| CN103449446B (en) | Method for preparing trichlorosilane | |
| CN204058313U (en) | A kind of apparatus system recycling chlorosilane slag slurry raffinate | |
| CN107304050B (en) | Polycrystalline silicon reduction exhaust recovery method and recovery system | |
| CN105174265B (en) | recovery system and recovery method | |
| CN103449448B (en) | Equipment for purification trichlorosilane | |
| JP5344113B2 (en) | Hydrogen separation and recovery method and hydrogen separation and recovery equipment | |
| JP2008143776A (en) | Hydrogen purification/collection method and hydrogen purification/collection facility | |
| CN113247862A (en) | High-purity electronic-grade hydrogen chloride production device and process | |
| CN112661115B (en) | Separation and purification method for deep dehydration and impurity removal of FTrPSA refined by anhydrous HF produced by fluorite method | |
| CN102874821A (en) | Preparation method of high-purity silicon dioxide | |
| CN103449440B (en) | Equipment for preparing polycrystalline silicon | |
| CN205011391U (en) | Recovery system | |
| CN202766304U (en) | Polysilicon production tail gas recycling device | |
| CN112744788B (en) | Separation and purification method for deep dehydration and impurity removal of FTrPSA refined by anhydrous HF (hydrogen fluoride) produced by fluosilicic acid method | |
| CN102849681A (en) | Method for removing chlorine included in hydrogen chloride gas | |
| CN103482630B (en) | Prepare the method for polysilicon | |
| CN103011172B (en) | The purifying method of impurity iodine in silicon tetrafluoride gas | |
| CN106032275B (en) | Trichlorosilane synthesis process and system | |
| CN107789966A (en) | The recovery system and method for tail gas in a kind of chlorination toluene production | |
| CN204022481U (en) | A kind of silicon tetrachloride purification system | |
| CN103466633B (en) | The method of purification trichlorosilane |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |