CN111036029B - Method for recovering waste gas in polycrystalline silicon production process - Google Patents
Method for recovering waste gas in polycrystalline silicon production process Download PDFInfo
- Publication number
- CN111036029B CN111036029B CN201811196199.4A CN201811196199A CN111036029B CN 111036029 B CN111036029 B CN 111036029B CN 201811196199 A CN201811196199 A CN 201811196199A CN 111036029 B CN111036029 B CN 111036029B
- Authority
- CN
- China
- Prior art keywords
- adsorption
- waste gas
- chlorosilane
- adsorption column
- polycrystalline silicon
- 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
- 239000002912 waste gas Substances 0.000 title claims abstract description 61
- 238000000034 method Methods 0.000 title claims abstract description 58
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 45
- 229910021420 polycrystalline silicon Inorganic materials 0.000 title claims abstract description 45
- 238000001179 sorption measurement Methods 0.000 claims abstract description 182
- 239000005046 Chlorosilane Substances 0.000 claims abstract description 63
- KOPOQZFJUQMUML-UHFFFAOYSA-N chlorosilane Chemical compound Cl[SiH3] KOPOQZFJUQMUML-UHFFFAOYSA-N 0.000 claims abstract description 63
- 239000012535 impurity Substances 0.000 claims abstract description 48
- 239000003463 adsorbent Substances 0.000 claims abstract description 35
- 229910052796 boron Inorganic materials 0.000 claims abstract description 23
- 229910052698 phosphorus Inorganic materials 0.000 claims abstract description 23
- ZOXJGFHDIHLPTG-UHFFFAOYSA-N Boron Chemical compound [B] ZOXJGFHDIHLPTG-UHFFFAOYSA-N 0.000 claims abstract description 21
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 claims abstract description 21
- 239000011574 phosphorus Substances 0.000 claims abstract description 21
- 229910001510 metal chloride Inorganic materials 0.000 claims abstract description 17
- 238000011049 filling Methods 0.000 claims abstract description 3
- 239000007789 gas Substances 0.000 claims description 35
- 239000011347 resin Substances 0.000 claims description 20
- 229920005989 resin Polymers 0.000 claims description 20
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims description 12
- 125000000524 functional group Chemical group 0.000 claims description 12
- 150000001805 chlorine compounds Chemical class 0.000 claims description 11
- 239000000126 substance Substances 0.000 claims description 11
- 230000008569 process Effects 0.000 claims description 10
- 229910052739 hydrogen Inorganic materials 0.000 claims description 9
- 239000001257 hydrogen Substances 0.000 claims description 9
- VXEGSRKPIUDPQT-UHFFFAOYSA-N 4-[4-(4-methoxyphenyl)piperazin-1-yl]aniline Chemical compound C1=CC(OC)=CC=C1N1CCN(C=2C=CC(N)=CC=2)CC1 VXEGSRKPIUDPQT-UHFFFAOYSA-N 0.000 claims description 7
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 7
- MROCJMGDEKINLD-UHFFFAOYSA-N dichlorosilane Chemical compound Cl[SiH2]Cl MROCJMGDEKINLD-UHFFFAOYSA-N 0.000 claims description 7
- 238000010438 heat treatment Methods 0.000 claims description 7
- 239000005049 silicon tetrachloride Substances 0.000 claims description 7
- ZDHXKXAHOVTTAH-UHFFFAOYSA-N trichlorosilane Chemical compound Cl[SiH](Cl)Cl ZDHXKXAHOVTTAH-UHFFFAOYSA-N 0.000 claims description 7
- 239000005052 trichlorosilane Substances 0.000 claims description 7
- MYRTYDVEIRVNKP-UHFFFAOYSA-N 1,2-Divinylbenzene Chemical compound C=CC1=CC=CC=C1C=C MYRTYDVEIRVNKP-UHFFFAOYSA-N 0.000 claims description 6
- 229910052757 nitrogen Inorganic materials 0.000 claims description 6
- 125000002887 hydroxy group Chemical group [H]O* 0.000 claims description 5
- 229920005591 polysilicon Polymers 0.000 claims description 5
- 239000011148 porous material Substances 0.000 claims description 5
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 claims description 4
- 229910052782 aluminium Inorganic materials 0.000 claims description 4
- 239000011575 calcium Substances 0.000 claims description 4
- 229910052791 calcium Inorganic materials 0.000 claims description 4
- 229910052742 iron Inorganic materials 0.000 claims description 4
- 239000004925 Acrylic resin Substances 0.000 claims description 3
- 229920000178 Acrylic resin Polymers 0.000 claims description 3
- OYPRJOBELJOOCE-UHFFFAOYSA-N Calcium Chemical compound [Ca] OYPRJOBELJOOCE-UHFFFAOYSA-N 0.000 claims description 3
- BZHJMEDXRYGGRV-UHFFFAOYSA-N Vinyl chloride Chemical compound ClC=C BZHJMEDXRYGGRV-UHFFFAOYSA-N 0.000 claims description 3
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 3
- 150000003440 styrenes Chemical class 0.000 claims description 3
- 125000000542 sulfonic acid group Chemical group 0.000 claims description 3
- 125000003277 amino group Chemical group 0.000 claims description 2
- 238000011084 recovery Methods 0.000 abstract description 19
- 239000002994 raw material Substances 0.000 abstract description 8
- 238000005265 energy consumption Methods 0.000 abstract description 5
- 238000005086 pumping Methods 0.000 description 26
- 238000002386 leaching Methods 0.000 description 16
- 238000009833 condensation Methods 0.000 description 8
- 230000005494 condensation Effects 0.000 description 8
- 238000007599 discharging Methods 0.000 description 5
- 150000002431 hydrogen Chemical class 0.000 description 5
- VSCWAEJMTAWNJL-UHFFFAOYSA-K aluminium trichloride Chemical compound Cl[Al](Cl)Cl VSCWAEJMTAWNJL-UHFFFAOYSA-K 0.000 description 4
- 238000004891 communication Methods 0.000 description 4
- 239000002699 waste material Substances 0.000 description 4
- 239000003513 alkali Substances 0.000 description 3
- 238000001816 cooling Methods 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- 230000008929 regeneration Effects 0.000 description 3
- 238000011069 regeneration method Methods 0.000 description 3
- UXVMQQNJUSDDNG-UHFFFAOYSA-L Calcium chloride Chemical compound [Cl-].[Cl-].[Ca+2] UXVMQQNJUSDDNG-UHFFFAOYSA-L 0.000 description 2
- 229910001628 calcium chloride Inorganic materials 0.000 description 2
- 239000001110 calcium chloride Substances 0.000 description 2
- 238000005984 hydrogenation reaction Methods 0.000 description 2
- 230000008676 import Effects 0.000 description 2
- FBAFATDZDUQKNH-UHFFFAOYSA-M iron chloride Chemical compound [Cl-].[Fe] FBAFATDZDUQKNH-UHFFFAOYSA-M 0.000 description 2
- 239000007788 liquid Substances 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 125000002924 primary amino group Chemical group [H]N([H])* 0.000 description 2
- 230000009467 reduction Effects 0.000 description 2
- 229920006395 saturated elastomer Polymers 0.000 description 2
- ZAMOUSCENKQFHK-UHFFFAOYSA-N Chlorine atom Chemical compound [Cl] ZAMOUSCENKQFHK-UHFFFAOYSA-N 0.000 description 1
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 1
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 1
- 230000002378 acidificating effect Effects 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 230000008901 benefit Effects 0.000 description 1
- 229910052801 chlorine Inorganic materials 0.000 description 1
- 239000000460 chlorine Substances 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000003912 environmental pollution Methods 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- IXCSERBJSXMMFS-UHFFFAOYSA-N hydrogen chloride Substances Cl.Cl IXCSERBJSXMMFS-UHFFFAOYSA-N 0.000 description 1
- 229910000041 hydrogen chloride Inorganic materials 0.000 description 1
- 238000000746 purification Methods 0.000 description 1
- 238000004064 recycling Methods 0.000 description 1
- 229910052710 silicon Inorganic materials 0.000 description 1
- 239000010703 silicon Substances 0.000 description 1
- 238000001228 spectrum Methods 0.000 description 1
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
- B01D53/02—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols by adsorption, e.g. preparative gas chromatography
- B01D53/04—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols by adsorption, e.g. preparative gas chromatography with stationary adsorbents
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B33/00—Silicon; Compounds thereof
- C01B33/02—Silicon
- C01B33/021—Preparation
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2253/00—Adsorbents used in seperation treatment of gases and vapours
- B01D2253/20—Organic adsorbents
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2257/00—Components to be removed
- B01D2257/20—Halogens or halogen compounds
- B01D2257/204—Inorganic halogen compounds
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2259/00—Type of treatment
- B01D2259/40—Further details for adsorption processes and devices
- B01D2259/40083—Regeneration of adsorbents in processes other than pressure or temperature swing adsorption
- B01D2259/40088—Regeneration of adsorbents in processes other than pressure or temperature swing adsorption by heating
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Inorganic Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Analytical Chemistry (AREA)
- General Chemical & Material Sciences (AREA)
- Oil, Petroleum & Natural Gas (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Silicon Compounds (AREA)
Abstract
The invention discloses a method for recovering waste gas in the production process of polycrystalline silicon, which uses an adsorption device to recover the waste gas, wherein the adsorption device comprises an adsorption column and comprises the following steps: 1) introducing waste gas in the production process of polycrystalline silicon into an adsorption column of an adsorption device, filling an adsorbent in the adsorption column, and adsorbing chlorosilane, boron, phosphorus and metal chloride in the waste gas by the adsorbent; 2) and (3) carrying out segmented analysis on the adsorption column, firstly analyzing the adsorbed chlorosilane, and then analyzing the other adsorbed impurities. According to the recovery method, the impurities adsorbed by the adsorption column are separated through segmented analysis, and the chlorosilane adsorbed by the adsorption column is separated from other impurities, so that the chlorosilane can be fully and effectively recycled, a large amount of impurities in the chlorosilane can be removed, the purity of the chlorosilane is improved, the recovery efficiency is high, the energy consumption is low, the impurity content in the chlorosilane can be reduced through selective recovery, and the quality of raw materials and products is improved.
Description
Technical Field
The invention belongs to the technical field of polycrystalline silicon production, and particularly relates to a method for recovering waste gas in a polycrystalline silicon production process.
Background
In the production process of polycrystalline silicon, in order to improve the product purity, waste gas and waste liquid rich in impurities need to be continuously discharged, so that the impurities are continuously led out of the system. The main components of waste discharge are as follows: the method is characterized in that hydrogen chloride, dichlorosilane, trichlorosilane, silicon tetrachloride, hydrogen, nitrogen, P, B, Fe, Al, Ca and other impurities are treated by adopting a method of leaching and absorbing alkali liquor, a large amount of alkali liquor is consumed by the method, the waste of hydrogen, silicon and chlorine which are raw materials for producing polycrystalline silicon is caused, and if the leaching process is not thorough, the acidic gas overflows to pollute the atmosphere and the environment.
In order to reduce environmental pollution and reduce resource waste, polysilicon production enterprises begin to adopt various methods to recycle waste gas, and the following methods are mainly adopted for recycling the waste gas in the current polysilicon production process: the deep cooling method is characterized in that the waste gas is deeply cooled by adopting a low-temperature leaching or condensing method, the temperature of the gas is reduced to be below-20 ℃, dichlorosilane, trichlorosilane and silicon tetrachloride in the gas are condensed into liquid, and therefore, part of effective substances chlorosilane in the waste gas is recycled. The method has the disadvantages that a large amount of cold energy needs to be consumed, the recovery rate is low, and the waste gas needs to be treated again by adopting an alkali liquor leaching method after being subjected to deep cooling.
Disclosure of Invention
The technical problem to be solved by the invention is to provide a method for recovering waste gas in the production process of polycrystalline silicon, aiming at the defects in the prior art, and the method is used for separating impurities adsorbed by an adsorption column through segmented analysis and separating chlorosilane adsorbed by the adsorption column from other impurities.
The technical scheme adopted for solving the technical problem of the invention is to provide a method for recovering waste gas in the production process of polycrystalline silicon, the method uses an adsorption device to recover the waste gas, the adsorption device comprises an adsorption column, and the method comprises the following steps:
1) introducing waste gas in the production process of polycrystalline silicon into an adsorption column of an adsorption device, filling an adsorbent in the adsorption column, and adsorbing chlorosilane, boron, phosphorus and metal chloride in the waste gas by the adsorbent;
2) and (3) carrying out segmented analysis on the adsorption column, firstly analyzing the adsorbed chlorosilane, and then analyzing the other adsorbed impurities.
The invention is suitable for treating the waste gas in the production process of the polycrystalline silicon, and the waste gas comprises the following components: tail gas containing low-boiling-point substances discharged from a rectification process, tail gas containing iron chloride, calcium chloride and aluminum chloride discharged from a cold hydrogenation process, and replacement gas for starting and stopping a reduction furnace.
Preferably, the adsorbent in step 1) adsorbs chlorosilane in the exhaust gas through physical adsorption, and adsorbs boron, phosphorus and metal chloride in the exhaust gas through chemical adsorption.
Preferably, the adsorbent packed in the adsorption column in step 1) is a resin containing a functional group that selectively adsorbs boron, phosphorus, and metal chloride.
Preferably, the adsorbent in step 1) is one or more of modified styrene resin, divinylbenzene resin, acrylic resin and vinyl chloride resin.
Preferably, the functional group selectively adsorbing boron, phosphorus and metal chloride in the step 1) is one or more of a sulfonic acid group, a hydroxyl group and an amine group.
Preferably, the pore diameter of the adsorbent filled in the adsorption column in the step 1) is 30-80 nm.
Preferably, the adsorption conditions in step 1) are as follows: not more than 60 ℃ and 0-50 KpaG.
Preferably, the resolving process in step 2) is specifically: firstly, resolving for 10-60 minutes at the temperature of 20-60 ℃ and under the pressure of not higher than-90 KpaG to obtain chlorosilane; then heating to 70-90 ℃, and resolving for 10-60 minutes under the pressure of not less than-95 KpaG to resolve the adsorbed other impurities.
Preferably, the adsorption device comprises at least three adsorption columns, wherein at least two adsorption columns are connected in series for performing the steps 1) and 2), at least one adsorption column is reserved, and the number of reserved adsorption columns is at least 1 less than that of the working adsorption columns.
Preferably, the off-gas in the production process of polycrystalline silicon comprises: the total content of trichlorosilane, silicon tetrachloride and dichlorosilane is 40-90 mas%, the total content of hydrogen and nitrogen is 9-60 mas%, and the total content of chlorides of boron, phosphorus and iron, chlorides of calcium and chlorides of aluminum is 0.01-1 mas%.
According to the method for recovering the waste gas in the production process of the polycrystalline silicon, the impurities adsorbed by the adsorption column are separated through segmented analysis, and the chlorosilane adsorbed by the adsorption column is separated from the rest impurities, so that the chlorosilane can be fully and effectively recycled, a large amount of impurities in the chlorosilane can be removed, the purity of the chlorosilane is improved, the recovery method is high in recovery efficiency and low in energy consumption, the content of the impurities in the chlorosilane can be reduced through selective recovery, and the quality of raw materials and products is improved.
Drawings
FIG. 1 is a schematic view of the structure of an adsorption apparatus used in the method for recovering an off-gas in the production of polycrystalline silicon in example 2 of the present invention.
In the figure: 1-a first adsorption column; 2-a second adsorption column; 3-a third adsorption column; 4-a first inlet valve; 5-a second inlet valve; 6-a third inlet valve; 7-a first communication valve; 8-a second communication valve; 9-a third communicating valve; 10-a first outlet valve; 11-a second outlet valve; 12-a third outlet valve; 13-a first evacuation valve; 14-a second vacuum-pumping valve; 15-a third vacuum-pumping valve; 16-a condensation valve; 17-leaching the valve; 18-a condensing unit; 19-rinsing device.
Detailed Description
In order to make the technical solutions of the present invention better understood, the present invention will be described in further detail with reference to the accompanying drawings and specific embodiments.
Example 1
The embodiment provides a method for recovering waste gas in a polycrystalline silicon production process, which uses an adsorption device to recover the waste gas, wherein the adsorption device comprises an adsorption column and comprises the following steps:
1) introducing waste gas in the production process of polycrystalline silicon into an adsorption column of an adsorption device to adsorb chlorosilane, boron, phosphorus and metal chloride in the waste gas;
2) and (3) carrying out segmented analysis on the adsorption column, firstly analyzing the adsorbed chlorosilane, and then analyzing the other adsorbed impurities.
In the method for recovering the waste gas in the production process of the polycrystalline silicon, the impurities adsorbed by the adsorption column are separated through segmented analysis, and the chlorosilane adsorbed by the adsorption column is separated from the rest impurities, so that the chlorosilane can be fully and effectively recycled, a large amount of impurities in the chlorosilane can be removed, the purity of the chlorosilane is improved, the recovery method is high in recovery efficiency and low in energy consumption, the impurity content in the recycled chlorosilane can be reduced through selective recovery, and the quality of raw materials and products is improved.
Example 2
As shown in fig. 1, the present embodiment provides an adsorption apparatus for use in a method of recovering exhaust gas from a polycrystalline silicon production process, comprising: at least three adsorption columns, wherein at least two adsorption columns are connected in series and used for performing adsorption in a working mode, at least one adsorption column is reserved, and the number of the reserved adsorption columns is at least 1 less than that of the working adsorption columns.
Specifically, adsorption equipment includes three adsorption columns in this embodiment, and wherein, two adsorption columns are established ties and are used for work execution to adsorb, and another adsorption column is reserve.
Specifically, the adsorption device used in the method for recovering exhaust gas in the polycrystalline silicon production process in the embodiment includes: a first adsorption column 1, a second adsorption column 2 and a third adsorption column 3,
the embodiment is suitable for treating the waste gas in the production process of polycrystalline silicon and comprises the following steps: tail gas containing low-boiling-point substances discharged from a rectification process, tail gas containing iron chloride, calcium chloride and aluminum chloride discharged from a cold hydrogenation process, and replacement gas for starting and stopping a reduction furnace.
Specifically, the exhaust gas in the production process of polycrystalline silicon in the present embodiment includes: the total content of trichlorosilane, silicon tetrachloride and dichlorosilane is 40-90 mas%, the total content of hydrogen and nitrogen is 9-60 mas%, and the total content of chlorides of boron, phosphorus and iron, chlorides of calcium and chlorides of aluminum is 0.01-1 mas%.
The embodiment provides a method for recovering waste gas in a polycrystalline silicon production process, which uses the adsorption device to recover the waste gas and comprises the following steps:
1) in the production process of polycrystalline silicon, waste gas enters a first adsorption column 1 from an upper pipe orifice of the first adsorption column 1 (an adsorbent is filled in the adsorption column), the first adsorption column 1 is used as a first-stage adsorption column to perform first-stage adsorption, then the waste gas enters a second adsorption column 2, the second adsorption column 2 is used as a second-stage adsorption column to perform second-stage adsorption, and two-stage adsorption is performed at 60 ℃ and 50 KpaG. The adsorbent adsorbs chlorosilane, boron, phosphorus and metal chloride in the waste gas. The lower the temperature, the more favorable the adsorption process, wherein, the adsorbent packed in the adsorption column is resin containing functional groups for selectively adsorbing boron, phosphorus and metal chloride, the functional groups are hydroxyl groups, and the functional groups can combine B, P and the metal chloride to play a role in separating impurities. Specifically, the adsorbent is a modified styrene resin. The aperture of the adsorbent is 30-80 nm, the adsorbent has the advantage of a porous structure, and chlorosilane can be adsorbed by utilizing intermolecular force, so that the chlorosilane can be recovered. The types and the quantity of the adsorbents filled in the two-stage adsorption columns are the same, and the two-stage adsorption mainly has the effects of improving the utilization rate of the adsorption device and reducing the construction investment of the adsorption device; meanwhile, the waste gas purification degree is improved, and the recovery rate is improved.
2) After an adsorption period, the first adsorption column 1 is first saturated, the first adsorption column 1 is cut out, and the second adsorption column 2 and the regenerated third adsorption column 3 are used as a first-stage adsorption column for first-stage adsorption and a second-stage adsorption column for second-stage adsorption.
3) In order to recover the desorbed chlorosilane without recovering the desorbed impurities, according to the properties of the adsorbent, the bond energy of N-, S-, OH-and boron, phosphorus and metal chloride after the combination of hydroxyl, amino and sulfonic acid groups on the adsorbent can be destroyed at a higher temperature, so that the boron, phosphorus and metal chloride can be released. Therefore, the segmented analysis is carried out on the cut first adsorption column 1 under the controlled analysis condition, the chlorosilane physically adsorbed and adsorbed in the resin pores as the adsorbent is analyzed and recovered under the pressure of-50 KpaG at the temperature of 20 ℃ for 10 minutes; and (3) heating to 90 ℃, resolving for 60 minutes under the pressure of-95 KpaG, resolving out the other adsorbed impurities and a small amount of chlorosilane by destroying the combination of chemical bonds and impurities, thereby completing the regeneration of the cut-out first adsorption column 1, cooling the regenerated adsorption column to the condition of having the re-investment, and leaching and discharging the other resolved impurities and a small amount of chlorosilane.
Specifically, three adsorption columns of the adsorption device are switched and alternately used, two adsorption columns are in an adsorption state in each adsorption period to perform two-stage adsorption, and one adsorption column is in a regeneration state.
Specifically, the adsorption device used in the method for recovering exhaust gas in the polycrystalline silicon production process in the embodiment includes: a first adsorption column 1, a second adsorption column 2 and a third adsorption column 3,
and in the production process of the polycrystalline silicon, the waste gas is discharged through a main discharge waste gas pipeline.
A first inlet valve 4 is arranged between the inlet of the first adsorption column 1 and the outward exhaust gas main pipeline, a second inlet valve 5 is arranged between the inlet of the second adsorption column 2 and the outward exhaust gas main pipeline, and a third inlet valve 6 is arranged between the inlet of the third adsorption column 3 and the outward exhaust gas main pipeline.
A first communicating valve 7 is arranged on a pipeline between the outlet of the first adsorption column 1 and the inlet of the second adsorption column 2, a second communicating valve 8 is arranged on a pipeline between the outlet of the second adsorption column 2 and the inlet of the third adsorption column 3, and a third communicating valve 9 is arranged on a pipeline between the outlet of the third adsorption column 3 and the inlet of the first adsorption column 1.
An outlet of the first adsorption column 1 is connected with a first outer discharge pipeline for discharging waste gas, and a first outlet valve 10 is arranged on the first outer discharge pipeline; the outlet of the second adsorption column 2 is connected with a second external exhaust pipeline for discharging waste gas, and a second outlet valve 11 is arranged on the second external exhaust pipeline; an outlet of the third adsorption column 3 is connected with a third outer discharge pipeline for discharging waste gas, and a third outlet valve 12 is arranged on the third outer discharge pipeline.
The outlet of the first adsorption column 1 is connected with a first vacuumizing pipeline for vacuumizing, and a first vacuumizing valve 13 is arranged on the first vacuumizing pipeline; the outlet of the second adsorption column 2 is connected with a second vacuum-pumping pipeline for vacuum-pumping, and a second vacuum-pumping valve 14 is arranged on the second vacuum-pumping pipeline; the outlet of the third adsorption column 3 is connected with a third vacuum-pumping pipeline for vacuum-pumping, and a third vacuum-pumping valve 15 is arranged on the third vacuum-pumping pipeline. The first vacuum-pumping pipeline, the second vacuum-pumping pipeline and the third vacuum-pumping pipeline in the embodiment are all connected with a vacuum-pumping device, and vacuum pumping is carried out through the vacuum-pumping device.
The operation method of the adsorption device in this embodiment is as follows:
in the using process, the discharged waste gas in the polycrystalline silicon production process enters the adsorption device from the discharged waste gas main pipeline, the first inlet valve 4, the first communicating valve 7, the second outlet valve 11 and the leaching valve 17 are opened,
the waste gas enters the first adsorption column 1 and the second adsorption column 2 from top to bottom in sequence, chlorosilane is adsorbed and impurities are combined in the contact process of the waste gas with the first adsorbent and the second adsorbent, the main component of the adsorbed gas is hydrogen, and the hydrogen enters the leaching device 19 from the outlet of the second adsorption column 2 for leaching.
After one adsorption period expires, the first adsorbent in the first adsorption column 1 first reaches adsorption saturation, the first adsorbent needs to be regenerated, the first inlet valve 4 and the first communication valve 7 are closed, the first vacuumizing valve 13 is opened, and chlorosilane and impurities adsorbed in the first adsorption column 1 are analyzed and separated in a heating and negative-pressure pumping mode. At this time, the second adsorption column 2 is not saturated to be adsorbed and can be used continuously, and the second adsorption column 2 and the third adsorption column 3 are communicated and put into use. And opening a second inlet valve, opening a second communication valve 8, opening a third outlet valve 12 and closing a second outlet valve 11, and enabling the waste gas to sequentially enter the second adsorption column 2 and the third adsorption column 3 from top to bottom. The first adsorption column 1, the second adsorption column 2 and the third adsorption column 3 are sequentially put into use in the system in this order.
Vacuumizing the first adsorption column 1 under the condition of no heating, opening a condensation valve 16, pumping the pressure in the first adsorption column 1 to-50 KPaG, maintaining the pressure for 10min at the temperature control range of 20 ℃, sending the pumped chlorosilane gas into a condensing device 18 for condensation and recovery, and storing the recovered chlorosilane as a polycrystalline silicon production raw material; and when the pressure in the first adsorption column 1 reaches-50 KPaG and is maintained for 10min, closing the condensation valve 16, heating the first adsorption column 1 to 90 ℃, opening the leaching valve 17, pumping the pressure in the first adsorption column 1 to-95 KPaG, and sending the pumped impurities and a small amount of chlorosilane gas into the leaching device 19 for discharging, wherein the content of the impurities in the chlorosilane is high, and the chlorosilane is not recycled.
When the pressure in the first adsorption column 1 is pumped to-95 KPaG, the first vacuumizing valve 13 is closed to cool the first adsorption column 1, and when the temperature is reduced to below 30 ℃, the first adsorption column 1 is put into use again.
In the operation process, adopt online chromatograph and spectrum appearance to the waste gas of the import of first adsorption column 1, the waste gas of the 2 exports of second adsorption column respectively and monitor gas composition, and the import waste gas of first adsorption column 1 includes: 60 mas% of trichlorosilane, 20 mas% of silicon tetrachloride, 8 mas% of dichlorosilane, 6 mas% of hydrogen, 5 mas% of nitrogen and 0.3 mas% of chlorides of boron, phosphorus and metal. The waste gas at the outlet of the second adsorption column 2 comprises: 3mas percent of trichlorosilane, 1mas percent of silicon tetrachloride, 1mas percent of dichlorosilane, 48mas percent of hydrogen, 42mas percent of nitrogen and 0.01mas percent of chlorides of boron, phosphorus and metal. The adsorption rate of chlorosilane can reach about 95%.
In the regeneration process of the adsorption column, the materials of the condensation system and the leaching system are respectively subjected to impurity detection at the outlet of the vacuum pumping system, and the impurity content of the materials recovered by the condensation system is as follows: p-100ppb, B-50ppb, Fe-500ppb, Al-200ppb, Ca-300 ppb; the impurity content of the discharged materials of the leaching system is as follows: p-1500ppb, B-1000ppb, Fe-20000ppb, Al-2000ppb, Ca-3500 ppb; the removal rate of impurities can reach about 96%.
In the method for recovering the waste gas in the production process of the polycrystalline silicon, the impurities adsorbed by the adsorption column are separated through segmented analysis, and the chlorosilane adsorbed by the adsorption column is separated from the rest impurities, so that the chlorosilane can be fully and effectively recycled, a large amount of impurities in the chlorosilane can be removed, the purity of the chlorosilane is improved, the recovery method is high in recovery efficiency and low in energy consumption, the impurity content in the recycled chlorosilane can be reduced through selective recovery, and the quality of raw materials and products is improved.
In the embodiment, modified resin with a selective adsorption function is used as an adsorbent, and macromolecular chlorosilane in waste gas is adsorbed by utilizing the porous structural characteristics of the resin, so that the chlorosilane can be recovered; specific functional groups on a resin macromolecular chain are utilized, impurity molecules in the waste gas are combined through chemical bonds to play a role in separating impurities, under the combined action of physical adsorption and chemical adsorption, chlorosilane in the waste gas is recycled, a large amount of impurities in the chlorosilane are removed, the chlorosilane with high purity is obtained, and the chlorosilane with high purity can be directly used as a production raw material.
Two adsorption columns of the adsorption device used in the method in the embodiment are used in series, namely, the waste gas is firstly subjected to first-stage adsorption through the first adsorption column 1 and then enters the second adsorption column 2 for second-stage adsorption, the adsorption recovery rate is improved through the two-stage adsorption, the chlorosilane recovery rate can reach more than 90%, and the purity of the recovered product is also greatly improved. The method adopted by the embodiment has high recovery efficiency and low energy consumption, and can reduce the content of impurities in the recovered chlorosilane and improve the quality of raw materials and products through selective recovery.
Example 3
This example provides a method for recovering exhaust gas from a polycrystalline silicon production process, which uses the adsorption apparatus of example 2 to recover the exhaust gas, and differs from the method of example 2 in that:
1) two-stage adsorption was carried out at 30 ℃ and 0 KpaG. The adsorbent filled in the adsorption column is resin containing functional groups for selectively adsorbing boron, phosphorus and metal chloride, the functional groups are sulfonic groups, and the adsorbent is divinylbenzene resin.
2) Analyzing the cut first adsorption column in segments at 40 ℃ and-20 KpaG for 40 minutes to analyze chlorosilane physically adsorbed in the resin pores serving as the adsorbent and recover the chlorosilane; heating to 80 deg.C, and desorbing at a pressure of not less than-135 KpaG for 10min to desorb the adsorbed impurities and small amount of chlorosilane by breaking the bonds between the chemical bonds and the impurities.
Example 4
This example provides a method for recovering exhaust gas from a polycrystalline silicon production process, which uses the adsorption apparatus of example 2 to recover the exhaust gas, and differs from the method of example 2 in that:
1) two stages of adsorption were carried out at 0 ℃ and 25 KpaG. The adsorbent filled in the adsorption column is resin containing functional groups for selectively adsorbing boron, phosphorus and metal chloride, the functional groups are hydroxyl and amino (the molar ratio is 1:1), and the adsorbent is acrylic resin and vinyl chloride resin (the mass ratio is 2: 1).
2) Analyzing the cut first adsorption column in segments at 60 ℃ under the pressure of-90 KpaG for 60 minutes to analyze chlorosilane physically adsorbed in the resin pores serving as the adsorbent and recover the chlorosilane; then heated to 70 ℃, and the mixture is resolved for 30 minutes under the pressure of not less than-115 KpaG, and the other adsorbed impurities and a small amount of chlorosilane are resolved out by breaking the combination of chemical bonds and impurities.
It will be understood that the above embodiments are merely exemplary embodiments taken to illustrate the principles of the present invention, which is not limited thereto. It will be apparent to those skilled in the art that various modifications and improvements can be made without departing from the spirit and substance of the invention, and these modifications and improvements are also considered to be within the scope of the invention.
Claims (10)
1. A method for recovering waste gas in the production process of polycrystalline silicon uses an adsorption device to recover the waste gas, the adsorption device comprises an adsorption column, and the method is characterized by comprising the following steps:
1) introducing waste gas in the production process of polycrystalline silicon into an adsorption column of an adsorption device, filling an adsorbent in the adsorption column, and adsorbing chlorosilane, boron, phosphorus and metal chloride in the waste gas by the adsorbent;
2) and (3) carrying out segmented analysis on the adsorption column, firstly analyzing the adsorbed chlorosilane, and then analyzing the other adsorbed impurities.
2. The method for recovering the waste gas generated in the production process of the polycrystalline silicon according to claim 1, wherein the adsorbent in the step 1) adsorbs chlorosilane in the waste gas through physical adsorption and adsorbs boron, phosphorus and metal chloride in the waste gas through chemical adsorption.
3. The method for recovering exhaust gas from the production of polycrystalline silicon according to claim 1 or 2, wherein the adsorbent in the step 1) is a resin having a functional group that selectively adsorbs boron, phosphorus, and metal chloride.
4. The method for recovering the waste gas in the polysilicon production process according to claim 3, wherein the adsorbent in the step 1) is one or more of modified styrene resin, divinylbenzene resin, acrylic resin and vinyl chloride resin.
5. The method for recovering exhaust gas from the production process of polycrystalline silicon according to claim 3, wherein the functional group selectively adsorbing boron, phosphorus and metal chloride in the step 1) is one or more of a sulfonic acid group, a hydroxyl group and an amine group.
6. The method for recovering the waste gas in the production process of the polycrystalline silicon according to claim 1 or 2, wherein the pore diameter of the adsorbent in the step 1) is 30-80 nm.
7. The method for recovering the exhaust gas from the production process of polycrystalline silicon according to any one of claims 1 and 2, wherein the adsorption conditions in the step 1) are as follows: not more than 60 ℃ and 0-50 KpaG.
8. The method for recovering the exhaust gas in the polysilicon production process according to any one of claims 1 and 2, wherein the step 2) analysis process is specifically as follows: firstly, resolving for 10-60 minutes at the temperature of 20-60 ℃ and under the pressure of not higher than-90 KpaG to obtain chlorosilane; then heating to 70-90 ℃, and resolving for 10-60 minutes under the pressure of not less than-95 KpaG to resolve the adsorbed other impurities.
9. The method for recovering the exhaust gas in the polysilicon production process according to any one of claims 1 and 2, wherein the adsorption device comprises at least three adsorption columns, wherein at least two adsorption columns are connected in series for performing the steps 1) and 2), at least one adsorption column is reserved, and the number of the reserved adsorption columns is at least 1 less than that of the adsorption columns in operation.
10. The method for recovering exhaust gas from the production of polycrystalline silicon according to any one of claims 1 and 2, wherein the exhaust gas from the production of polycrystalline silicon comprises: the total content of trichlorosilane, silicon tetrachloride and dichlorosilane is 40-90 mas%, the total content of hydrogen and nitrogen is 9-60 mas%, and the total content of chlorides of boron, phosphorus and iron, chlorides of calcium and chlorides of aluminum is 0.01-1 mas%.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811196199.4A CN111036029B (en) | 2018-10-15 | 2018-10-15 | Method for recovering waste gas in polycrystalline silicon production process |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811196199.4A CN111036029B (en) | 2018-10-15 | 2018-10-15 | Method for recovering waste gas in polycrystalline silicon production process |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN111036029A CN111036029A (en) | 2020-04-21 |
| CN111036029B true CN111036029B (en) | 2022-03-04 |
Family
ID=70230244
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201811196199.4A Active CN111036029B (en) | 2018-10-15 | 2018-10-15 | Method for recovering waste gas in polycrystalline silicon production process |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111036029B (en) |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112121465B (en) * | 2020-10-21 | 2025-08-26 | 新疆大全新能源股份有限公司 | A method for filling adsorption/deproportionation resin |
| US12391559B2 (en) | 2020-11-05 | 2025-08-19 | Wacker Chemie Ag | Process for removing an impurity from a chlorosilane mixture |
| CN113603096A (en) * | 2021-05-26 | 2021-11-05 | 中国科学院过程工程研究所 | Method for adsorbing trace boron and phosphorus impurities in chlorosilane system |
| CN115006861B (en) * | 2022-06-10 | 2024-01-30 | 内蒙古新特硅材料有限公司 | System and process for separating polycrystalline silicon reduction tail gas absorption rich liquid and condensate |
| CN116637468A (en) * | 2023-05-02 | 2023-08-25 | 瓮福（集团）有限责任公司 | Method for recycling organic matters in wet-process purified phosphoric acid tail gas |
| CN118221287B (en) * | 2024-02-02 | 2025-02-07 | 东莞市倍益清环保科技有限公司 | A carbon fiber filter element |
Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5320817A (en) * | 1992-08-28 | 1994-06-14 | Novapure Corporation | Process for sorption of hazardous waste products from exhaust gas streams |
| CN102058992A (en) * | 2010-11-13 | 2011-05-18 | 天津大学 | Clapboard adsorption device and method for removing boron impurities in chlorosilane system |
| CN102574680A (en) * | 2009-10-14 | 2012-07-11 | 信越化学工业株式会社 | Hydrogen recovery system and hydrogen separation and recovery method |
| CN102580459A (en) * | 2012-03-02 | 2012-07-18 | 洛阳晶辉新能源科技有限公司 | Method for treating waste gas in production of polycrystalline silicon |
| CN105174265A (en) * | 2015-08-25 | 2015-12-23 | 中国恩菲工程技术有限公司 | Recovery system and recovery method |
| CN105480981A (en) * | 2014-09-19 | 2016-04-13 | 新特能源股份有限公司 | Method and device for recovering dichlorosilane from tail gas in reduction production of polysilicon |
| CN105731465A (en) * | 2016-02-29 | 2016-07-06 | 天津大学 | Method and equipment for removing boron and phosphorous by utilizing chlorosilane fixed bed chemical adsorption reaction method |
| CN106554021A (en) * | 2015-09-30 | 2017-04-05 | 新特能源股份有限公司 | A kind of rectification tail gas recovery system |
| CN107648979A (en) * | 2016-07-26 | 2018-02-02 | 新特能源股份有限公司 | The method and system of tail gas in a kind of processing production of polysilicon |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP6179246B2 (en) * | 2012-07-31 | 2017-08-16 | 三菱マテリアル株式会社 | Polycrystalline silicon manufacturing method and manufacturing apparatus |
| CN106061585B (en) * | 2014-01-24 | 2018-12-11 | 韩华化学株式会社 | The purification method and cleaning equipment of exhaust gas |
| KR20160143994A (en) * | 2015-06-05 | 2016-12-15 | 주식회사 케이씨씨 | Method for removing phosphorous compounds from chlorosilanes |
-
2018
- 2018-10-15 CN CN201811196199.4A patent/CN111036029B/en active Active
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5320817A (en) * | 1992-08-28 | 1994-06-14 | Novapure Corporation | Process for sorption of hazardous waste products from exhaust gas streams |
| CN102574680A (en) * | 2009-10-14 | 2012-07-11 | 信越化学工业株式会社 | Hydrogen recovery system and hydrogen separation and recovery method |
| CN102058992A (en) * | 2010-11-13 | 2011-05-18 | 天津大学 | Clapboard adsorption device and method for removing boron impurities in chlorosilane system |
| CN102580459A (en) * | 2012-03-02 | 2012-07-18 | 洛阳晶辉新能源科技有限公司 | Method for treating waste gas in production of polycrystalline silicon |
| CN105480981A (en) * | 2014-09-19 | 2016-04-13 | 新特能源股份有限公司 | Method and device for recovering dichlorosilane from tail gas in reduction production of polysilicon |
| CN105174265A (en) * | 2015-08-25 | 2015-12-23 | 中国恩菲工程技术有限公司 | Recovery system and recovery method |
| CN106554021A (en) * | 2015-09-30 | 2017-04-05 | 新特能源股份有限公司 | A kind of rectification tail gas recovery system |
| CN105731465A (en) * | 2016-02-29 | 2016-07-06 | 天津大学 | Method and equipment for removing boron and phosphorous by utilizing chlorosilane fixed bed chemical adsorption reaction method |
| CN107648979A (en) * | 2016-07-26 | 2018-02-02 | 新特能源股份有限公司 | The method and system of tail gas in a kind of processing production of polysilicon |
Non-Patent Citations (2)
| Title |
|---|
| "First Principles Investigation of HCl, H2, and Chlorosilane Adsorption";Shwetank Yadav et al.;《The Journal Of Physical Chemistry》;20180906;第122卷(第35期);第20252-20260页 * |
| "高效除三氯氢硅中痕量硼、磷工艺研究进展";钱浩等;《化学工业与工程》;20170112;第35卷(第2期);第42-48页 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN111036029A (en) | 2020-04-21 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN111036029B (en) | Method for recovering waste gas in polycrystalline silicon production process | |
| KR101837535B1 (en) | Methane recovering method and methane recovering apparatus | |
| CN107789949A (en) | A kind of gas separating method of negative pressure pressure-variable adsorption | |
| KR20100126660A (en) | CO2 Recovery Plant and Method | |
| JP6104935B2 (en) | Gas improvement method | |
| CN113277471B (en) | Method and device for recovering reduction tail gas in polycrystalline silicon production | |
| CN103111157A (en) | Method for purifying and recovering discharge tail gas of regeneration process of adsorption tower in polycrystalline silicon production | |
| CN102580459A (en) | Method for treating waste gas in production of polycrystalline silicon | |
| KR20110115534A (en) | How to recover nf3 from adsorption work | |
| JP2009226257A (en) | Process for separation of blast furnace gas, and system of separating blast furnace gas | |
| CN106902617A (en) | A kind of high concentration VOC air purifying recovering apparatus and method | |
| CN103170214A (en) | Method for recovering methane chloride from organic silicon synthetic tail gas | |
| CN101279178B (en) | A method and device for recovering H2 in tail gas produced from trichlorosilane | |
| JPS63107720A (en) | Method for separating and removing water content and carbon dioxide gas in air | |
| CN107352510B (en) | Polycrystalline silicon reduction exhaust recovery method and recovery system | |
| CN202620982U (en) | Pressure swing adsorption system for separation of mixed gas including hydrogen and chlorosilane and/or chlorine hydride | |
| CN102718621B (en) | Method for selectively desorbing carbon disulfide in coarse benzene | |
| CN206444410U (en) | Transformation reclaims hydrogen adsorption tower | |
| CN102899096B (en) | Method for decarburizing coke oven gas | |
| CN101973603A (en) | Desorption method for reutilization of desorption agent | |
| JP2012254421A (en) | Siloxane removal method and methane recovery method | |
| JP2001335305A (en) | Co gas/h2 gas recovery equipment and method for recovering co gas/h2 gas | |
| JPS59116115A (en) | Method for recovering carbon monoxide | |
| CN113772673A (en) | A process system and method for recovering and purifying carbon dioxide from lime kiln tail gas | |
| JPS621766B2 (en) |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| EE01 | Entry into force of recordation of patent licensing contract | ||
| EE01 | Entry into force of recordation of patent licensing contract |
Application publication date: 20200421 Assignee: Inner Mongolia Xinte silicon material Co.,Ltd. Assignor: XINTE ENERGY Co.,Ltd. Contract record no.: X2022990000326 Denomination of invention: Recovery method of waste gas in polysilicon production process Granted publication date: 20220304 License type: Common License Record date: 20220627 Application publication date: 20200421 Assignee: Xinte silicon based new materials Co.,Ltd. Assignor: XINTE ENERGY Co.,Ltd. Contract record no.: X2022990000325 Denomination of invention: Recovery method of waste gas in polysilicon production process Granted publication date: 20220304 License type: Common License Record date: 20220627 |