CN115468419A - Device and method for removing boron impurities in metallurgical-grade silicon in ore-smelting furnace - Google Patents
Device and method for removing boron impurities in metallurgical-grade silicon in ore-smelting furnace Download PDFInfo
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- CN115468419A CN115468419A CN202210959737.0A CN202210959737A CN115468419A CN 115468419 A CN115468419 A CN 115468419A CN 202210959737 A CN202210959737 A CN 202210959737A CN 115468419 A CN115468419 A CN 115468419A
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- 229910052710 silicon Inorganic materials 0.000 title claims abstract description 93
- 239000010703 silicon Substances 0.000 title claims abstract description 93
- 238000003723 Smelting Methods 0.000 title claims abstract description 42
- 239000012535 impurity Substances 0.000 title claims abstract description 32
- ZOXJGFHDIHLPTG-UHFFFAOYSA-N Boron Chemical compound [B] ZOXJGFHDIHLPTG-UHFFFAOYSA-N 0.000 title claims abstract description 30
- 229910052796 boron Inorganic materials 0.000 title claims abstract description 30
- 238000000034 method Methods 0.000 title claims description 34
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 claims abstract description 91
- 239000002893 slag Substances 0.000 claims abstract description 68
- 239000007788 liquid Substances 0.000 claims abstract description 51
- 238000010438 heat treatment Methods 0.000 claims abstract description 19
- 238000003756 stirring Methods 0.000 claims abstract description 12
- 238000012546 transfer Methods 0.000 claims abstract description 10
- 229910004298 SiO 2 Inorganic materials 0.000 claims description 46
- 239000003795 chemical substances by application Substances 0.000 claims description 34
- 238000004321 preservation Methods 0.000 claims description 17
- 238000002156 mixing Methods 0.000 claims description 12
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 8
- 239000002994 raw material Substances 0.000 claims description 8
- 238000006243 chemical reaction Methods 0.000 claims description 6
- 235000012239 silicon dioxide Nutrition 0.000 claims description 4
- 239000000377 silicon dioxide Substances 0.000 claims description 4
- 230000000149 penetrating effect Effects 0.000 claims 1
- 238000004519 manufacturing process Methods 0.000 abstract description 7
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 abstract description 5
- 239000010439 graphite Substances 0.000 abstract description 3
- 229910002804 graphite Inorganic materials 0.000 abstract description 3
- 229910052799 carbon Inorganic materials 0.000 abstract description 2
- 229910052810 boron oxide Inorganic materials 0.000 description 6
- 229910004261 CaF 2 Inorganic materials 0.000 description 5
- JKWMSGQKBLHBQQ-UHFFFAOYSA-N diboron trioxide Chemical compound O=BOB=O JKWMSGQKBLHBQQ-UHFFFAOYSA-N 0.000 description 5
- 230000007797 corrosion Effects 0.000 description 3
- 238000005260 corrosion Methods 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 229910021420 polycrystalline silicon Inorganic materials 0.000 description 3
- 229920005591 polysilicon Polymers 0.000 description 3
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N Iron oxide Chemical compound [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 description 2
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- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- 229910052742 iron Inorganic materials 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 230000001590 oxidative effect Effects 0.000 description 2
- 238000000926 separation method Methods 0.000 description 2
- XUKUURHRXDUEBC-SXOMAYOGSA-N (3s,5r)-7-[2-(4-fluorophenyl)-3-phenyl-4-(phenylcarbamoyl)-5-propan-2-ylpyrrol-1-yl]-3,5-dihydroxyheptanoic acid Chemical compound C=1C=CC=CC=1C1=C(C=2C=CC(F)=CC=2)N(CC[C@@H](O)C[C@H](O)CC(O)=O)C(C(C)C)=C1C(=O)NC1=CC=CC=C1 XUKUURHRXDUEBC-SXOMAYOGSA-N 0.000 description 1
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- WUKWITHWXAAZEY-UHFFFAOYSA-L calcium difluoride Chemical compound [F-].[F-].[Ca+2] WUKWITHWXAAZEY-UHFFFAOYSA-L 0.000 description 1
- 229910021419 crystalline silicon Inorganic materials 0.000 description 1
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- 238000011031 large-scale manufacturing process Methods 0.000 description 1
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- 238000010248 power generation Methods 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F27—FURNACES; KILNS; OVENS; RETORTS
- F27B—FURNACES, KILNS, OVENS, OR RETORTS IN GENERAL; OPEN SINTERING OR LIKE APPARATUS
- F27B17/00—Furnaces of a kind not covered by any preceding group
-
- 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
- C01B33/037—Purification
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C1/00—Making non-ferrous alloys
- C22C1/02—Making non-ferrous alloys by melting
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F27—FURNACES; KILNS; OVENS; RETORTS
- F27D—DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS, OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
- F27D11/00—Arrangement of elements for electric heating in or on furnaces
- F27D11/08—Heating by electric discharge, e.g. arc discharge
- F27D11/10—Disposition of electrodes
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F27—FURNACES; KILNS; OVENS; RETORTS
- F27D—DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS, OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
- F27D3/00—Charging; Discharging; Manipulation of charge
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F27—FURNACES; KILNS; OVENS; RETORTS
- F27D—DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS, OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
- F27D3/00—Charging; Discharging; Manipulation of charge
- F27D2003/0034—Means for moving, conveying, transporting the charge in the furnace or in the charging facilities
- F27D2003/0083—Means for stirring the charge
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- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Mechanical Engineering (AREA)
- Organic Chemistry (AREA)
- General Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Inorganic Chemistry (AREA)
- Silicon Compounds (AREA)
Abstract
The invention discloses a device for removing boron impurities in metallurgical-grade silicon in an ore-smelting furnace, which comprises the ore-smelting furnace, wherein a heating electrode is fixedly connected and arranged at the bottom in the ore-smelting furnace, a heat transfer plate is fixedly connected and arranged in the ore-smelting furnace, the heat transfer plate is positioned on the upper side of the heating electrode and is correspondingly matched with the heating electrode, a feed inlet is arranged on the upper left side in the ore-smelting furnace, a feed pipe is fixedly connected and arranged on the lower side of the feed inlet, a piston block is sleeved in the feed inlet in a matching manner, the piston block penetrates through the feed inlet, a rotating rod is rotatably connected and arranged on the upper side in the ore-smelting furnace, the rotating rod is positioned on the right side of the feed inlet, and a plurality of stirring rods are symmetrically and fixedly connected and arranged on the side wall of the rotating rod. The invention is smelted in the ore-smelting furnace, a graphite crucible is not needed, the production cost is reduced, the silicon liquid is prevented from being polluted by carbon elements, the boron impurities obtain good mass transfer conditions between the slag liquid and the silicon liquid, and the slag silicon is separated more thoroughly.
Description
Technical Field
The invention relates to the technical field of metallurgical-grade silicon purification, in particular to a device and a method for removing boron impurities in metallurgical-grade silicon in a submerged arc furnace.
Background
Because the traditional energy sources have various defects of non-regeneration, environmental pollution and the like, the crystalline silicon solar cell gradually attracts the global attention with the advantages of environmental protection, about 1800 ten thousand kilowatt photovoltaic power generation equipment is newly added every year in China, in order to meet the requirement of rapid development of the photovoltaic equipment, researchers make great efforts in the field of low-cost short-process production of solar grade silicon, the boron content has great influence on the photoelectric conversion efficiency and stability of the solar cell, and generally, the B content in qualified solar silicon wafers is less than 0.3 multiplied by 10 -6 P content of 0.5X 10 -6 The metal impurities of Fe, al, ca, etc. are 0.1X 10 -6 (ii) a The Fe, al, ca and other metal impurities can be removed by a directional solidification method due to small segregation coefficient; impurities with large saturated vapor pressure such as P, ca and the like can be removed by vacuum melting, but B impurities cannot be removed by the two methods, so that the exploration of a B removing technology with low cost, low energy consumption and large-scale production capacity is a hot research field for purifying silicon by a metallurgical method.
Chinese patent CN02135841.9 (Zheng Zhixiong, a high purity silicon for solar cell and method for producing the same) discloses a method for preparing solar grade polysilicon by adding fluorite, iron oxide, lime, etc. to a silicon melt, which is essentially by CaF 2 Oxidizing B impurities in silicon into BO by CaO slagging oxidation refining method 2 O 3 ，B 2 O，BO 2 ，B 2 O 2 And when the boron oxide is used, the property that the Gibbs free energy of the boron oxide in a slag system is lower than that of the boron oxide in silicon liquid is utilized, so that the boron oxide tends to enter the slag liquid, and the impurity B in the silicon liquid is removed. The laboratory of metallurgy and mineral processing of Xiamen university passes through CaO-SiO 2 -CaF 2 The B content is successfully reduced to 0 at 1650-1750 ℃ in a slag-forming experiment of a BaO slag system15-0.7ppmw (Cai Jing, chen Chao, luo Xuetao, progress in boron removal for highly pure metallurgical silicon, materials reports, 2009, 23 (12): 81-84).
U.S. Pat. No. 5, 200501391485 (Fujiwara Hiroyasu et al, silicon purifying method, slag for purifying Silicon, and purified Silicon) is prepared by using CaO-SiO 2 The slag system reduces the silicon B content from 7.4ppm to 0.8 ppm, but the process requires blowing and slagging to be carried out simultaneously.
Patent CN101671023A discloses a method for removing boron by polysilicon slagging, which adopts two slagging agents, the first is Na 2 O+SiO 2 (ii) a The second is CaO + CaF 2 +SiO 2 The B content in the polysilicon can be reduced to 0.18ppm, but the process requires vacuum conditions.
The production process of the process has the following disadvantages: 1. the short service time of a graphite crucible used in the smelting process causes higher slagging and boron removal cost; 2. CaF 2 The addition of (2) causes severe corrosion to the crucible and equipment; 3. the blowing and vacuum operations have high requirements on production equipment, so that the process is not beneficial to popularization.
Disclosure of Invention
The invention aims to solve the defects in the prior art, such as: the device and the method for removing boron impurities in metallurgical-grade silicon in the submerged arc furnace have the advantages of high integral boron removal cost, serious corrosion to equipment, high process requirement and no contribution to popularization and production.
In order to achieve the purpose, the invention adopts the following technical scheme:
the utility model provides a get rid of device of metallurgical grade silicon middle boron impurity in ore smelting furnace, includes the hot stove in ore smelting furnace, bottom fixed connection is equipped with heating electrode in stating the hot stove in ore smelting furnace, fixed connection is equipped with the temperature-transfer board in the ore smelting furnace, the temperature-transfer board is located heating electrode's upside and heating electrode matching and corresponds the setting, the last left side of the hot stove in ore smelting furnace is equipped with the feed inlet, feed inlet downside fixed connection is equipped with the inlet pipe, the matching cover is equipped with the piston piece in the feed inlet, the piston piece runs through in the feed inlet setting, upside rotation connection is equipped with the dwang in the hot stove in ore smelting furnace, the dwang is located the right side setting of feed inlet, dwang lateral wall symmetry fixed connection is equipped with a plurality of puddlers, the fixed cover is equipped with first gear in the dwang outside still, first gear is located the upside setting of a plurality of puddlers, be equipped with the control lever in the hot stove in ore smelting furnace, the control lever runs through in the hot stove setting in ore smelting furnace, the control lever is equipped with the control ring in the hot stove, the removal control device in the hot stove in ore smelting furnace.
Preferably, the mobile control device comprises a fixing plate fixedly connected and arranged in the submerged arc furnace, the fixing plate is arranged at the lower side of the second gear, an inner gear ring is arranged at the upper side of the fixing plate, a ring groove is formed in the upper side of the fixing plate, two sliding rods are symmetrically and slidably connected in the ring groove and penetrate through the ring groove and the inner gear ring in a fixed connection mode, the inner gear ring and the second gear ring are correspondingly arranged in a matched mode, a third gear which is the same as the second gear is sleeved in the inner gear ring in a meshed mode, a first spring is arranged at the lower side of the third gear in a fixed connection mode, the other side of the first spring is fixedly connected with the fixing plate, a wire guide groove is formed in the outer side of the inner gear ring, a control wire is wound and connected in the wire guide groove, the control wire penetrates through the wire guide groove, a pull ring is arranged at the upper side of the control ring in a fixed connection mode, and the control wire and the pull ring are fixedly connected and arranged.
Preferably, a first fixing ring is fixedly connected to the inner right side of the submerged arc furnace, a second fixing ring is fixedly connected to the inner upper side of the submerged arc furnace, and the control line penetrates through the first fixing ring and the second fixing ring.
Preferably, the upside of fixed plate is equipped with the quad slit, sliding sleeve is equipped with the quad slit in the quad slit, the quad slit runs through in the quad slit, just quad slit and third gear fixed connection set up.
Preferably, the hot stove inside wall in ore deposit is equipped with the spout, sliding connection is equipped with the slider in the spout, the slider runs through in spout and control ring fixed connection setting.
Preferably, the control rod is located in a submerged arc furnace and sleeved with a control cylinder, the control cylinder is located on the upper side of the second gear and arranged, the control rod is located in the control cylinder and fixedly sleeved with a moving ring, a second spring is fixedly connected to the lower side of the moving ring, a rotating ring is fixedly connected to the other side of the second spring, the rotating ring is rotatably connected to the bottom of the control cylinder, a limiting ring is fixedly sleeved in the control cylinder and arranged on the upper side of the moving ring in a contact connection mode with the moving ring.
A method for removing boron impurities from metallurgical grade silicon in a submerged arc furnace, comprising the steps of:
s1, firstly, taking out a piston block from a feed inlet, putting metallurgical silicon into a submerged arc furnace, starting a heating electrode, and smelting until all raw material silicon is changed into silicon liquid;
s2, mixing the Na 2 CO 3 -SiO 2 Adding slag agents into the silicon liquid through a feeding hole and a feeding pipe, and preserving heat;
s3, mixing the evenly mixed CaO-SiO 2 Adding slag agents into the silicon liquid through a feeding hole and a feeding pipe, and preserving heat;
s4, after the whole reaction is finished, the control rod is moved downwards, the control rod drives the moving ring to move downwards, the moving ring compresses the second spring, the control rod can also drive the second gear to move downwards, the second gear is in contact with the third gear and drives the third gear to move downwards, the third gear compresses the first spring until the third gear is disconnected with the inner gear, the inner gear is meshed with the second gear, the control rod is rotated and drives the inner gear to rotate through the second gear, the control ring is moved downwards under the action of the control line and the self gravity of the control ring until the control ring moves to the upper side of a slag boundary layer, the slag liquid is extracted by using a hose and a corresponding press machine, the operation is repeated, and then the silicon liquid is extracted.
Preferably, the raw materials of silicon and Na are carried out 2 CO 3 -SiO 2 Slag agent and CaO-SiO 2 In the process of adding the slag agent, the control rod is rotated,the control rod drives the rotating rod to rotate through the second gear and the first gear, the rotating rod drives the stirring rod to rotate, corresponding stirring operation is carried out, and the mixing time is shortened.
Preferably, na in said step S2 2 CO 3 -SiO 2 The weight ratio of the slag agent to the metallurgical silicon is 45; the Na is 2 CO 3 -SiO 2 Na in slag agent 2 CO 3 The mass percentage of the silicon dioxide is 64 percent to 69.5 percent, and the balance is SiO 2 (ii) a The heat preservation temperature is 1800-1950 ℃; the heat preservation time is 20-30 minutes.
Preferably, caO-SiO in the step S3 2 The weight ratio of the slag agent to the metallurgical silicon is 87; the CaO-SiO 2 The slag agent CaO accounts for 70-74 percent by mass, and the balance is SiO 2 (ii) a The heat preservation temperature is 1800-1900 ℃; the heat preservation time is 30-40 minutes.
Compared with the prior art, the invention has the beneficial effects that:
1. because the smelting is carried out in the ore-smelting furnace, a graphite crucible is not needed, the production cost is reduced, and the silicon liquid is prevented from being polluted by carbon;
2. the prepared slag agent does not contain CaF 2 The corrosion to equipment in the smelting process is relieved;
3、Na 2 O-SiO 2 the slag liquid is positioned above the silicon liquid to form CaO-Na 2 O-SiO 2 After the slag liquid is submerged, the silicon liquid floats upwards, and impurities B obtain good mass transfer conditions between the slag liquid and the silicon liquid; 4. the slag silicon liquid can be discharged after being layered, and the separation effect is good.
Drawings
FIG. 1 is a schematic structural diagram of an apparatus and a method for removing boron impurities from metallurgical-grade silicon in a submerged arc furnace according to the present invention;
FIG. 2 is a schematic top connection diagram between a control ring and a submerged arc furnace in an apparatus for removing boron impurities from metallurgical grade silicon in the submerged arc furnace and a method thereof according to the present invention;
FIG. 3 is a schematic view showing the connection of a control ring, a hose and a pull ring in the apparatus for removing boron impurities from metallurgical-grade silicon in a submerged arc furnace and the method thereof according to the present invention;
FIG. 4 is an enlarged view of the structure at A in FIG. 1;
FIG. 5 is an enlarged view of the structure of a control cylinder in the apparatus for removing boron impurities from metallurgical grade silicon in a submerged arc furnace and the method thereof according to the present invention;
FIG. 6 is a schematic diagram of an apparatus for removing boron impurities from metallurgical-grade silicon in a submerged arc furnace and a method thereof according to the present invention.
In the figure: 1 submerged arc furnace, 2 heat transfer plates, 3 heating electrodes, 4 rotating rods, 5 stirring rods, 6 first gears, 7 feed inlets, 8 feed pipes, 9 piston blocks, 10 control rods, 11 second gears, 12 third gears, 13 first springs, 14 fixing plates, 15 square holes, 16 square rods, 17 second fixing rings, 18 control cylinders, 19 control rings, 20 pull rings, 21 sliding grooves, 22 sliding blocks, 23 hoses, 24 inner toothed rings, 25 wire grooves, 26 control wires, 27 first fixing rings, 28 annular grooves, 29 sliding rods, 30 moving rings, 31 second springs, 32 limiting rings and 33 rotating rings.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments.
In the description of the present invention, it is to be understood that the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", and the like, indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, are merely for convenience in describing the present invention and simplifying the description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention.
Referring to fig. 1-6, a device for removing boron impurities in metallurgical-grade silicon in an ore-smelting furnace 1, comprising an ore-smelting furnace 1, wherein a heating electrode 3 is fixedly connected and arranged at the bottom of the ore-smelting furnace 1, a temperature transmission plate 2 is fixedly connected and arranged in the ore-smelting furnace 1, the temperature transmission plate 2 is arranged at the upper side of the heating electrode 3 and is correspondingly matched with the heating electrode 3, the heating electrode 3 is the prior art, and therefore redundant description is not provided, a feed inlet 7 is arranged at the upper left side in the ore-smelting furnace 1, a feed pipe 8 is fixedly connected and arranged at the lower side of the feed inlet 7, a piston block 9 is sleeved in the feed inlet 7 in a matching manner, the piston block 9 penetrates through the feed inlet 7, a rotating rod 4 is rotatably connected and arranged at the upper side in the ore-smelting furnace 1, the rotating rod 4 is arranged at the right side of the feed inlet 7, a plurality of stirring rods 5 are fixedly connected and symmetrically arranged on the side wall of the rotating rod 4, a first gear 6 is fixedly sleeved outside the rotating rod 4, the plurality of stirring rods 5, a control rod 10 is arranged in the submerged arc furnace 1, the control rod 10 is arranged to penetrate through the submerged arc furnace 1, the control rod 10 is fixedly connected with a second gear 11 in the submerged arc furnace 1, the second gear 11 is meshed with a first gear 6 and is connected with the first gear, a hose 23 is arranged in the submerged arc furnace 1 in a fixed connection manner, the hose 23 penetrates through the submerged arc furnace 1, a control ring 19 is fixedly connected with one end of the hose 23 in the submerged arc furnace 1, a mobile control device of the control ring 19 is arranged in the submerged arc furnace 1, the mobile control device comprises a fixed plate 14 fixedly connected with the submerged arc furnace 1, the fixed plate 14 is arranged at the lower side of the second gear 11, an inner toothed ring 24 is arranged at the upper side of the fixed plate 14, an annular groove 28 is arranged at the upper side of the fixed plate 14, two sliding rods 29 are symmetrically connected with the annular groove 28 in the annular groove 28, and the two sliding rods 29 penetrate through the annular groove 28 and the inner toothed ring 24 in a fixed connection manner, the inner gear ring 24 and the second gear 11 are correspondingly arranged in a matching manner, a third gear 12 which is the same as the second gear 11 is sleeved in the inner gear ring 24, a first spring 13 is fixedly connected to the lower side of the third gear 12, the other side of the first spring 13 is fixedly connected with the fixing plate 14, a wire guide groove 25 is arranged on the outer side of the inner gear ring 24, a control wire 26 is wound in the wire guide groove 25 and is connected with the wire guide groove 25, the control wire 26 penetrates through the wire guide groove 25 and is arranged, a pull ring 20 is fixedly connected to the upper side of the control ring 19, the control wire 26 is fixedly connected with the pull ring 20, a first fixing ring 27 is fixedly connected to the right side of the submerged arc furnace 1, a second fixing ring 17 is fixedly connected to the inner side of the submerged arc furnace 1, the control wire 26 penetrates through the first fixing ring 27 and the second fixing ring 17, the first fixing ring 27 is matched with the second fixing ring 17 to complete simple limiting operation of the movement track of the control wire 26, a square hole 15 is arranged on the upper side of the fixing plate 14, a square rod 16 is sleeved in the sliding hole 15, the square rod 16 is arranged in the sliding sleeve, the square rod 16 is arranged in the sliding groove 15, the sliding groove 21, the sliding control groove 31 is arranged on the sliding groove 21 which the sliding groove 22 which is arranged to control the sliding control of the sliding control rod 21 which is arranged, the sliding control of the sliding chute 18 which is arranged, the sliding control of the sliding chute 18 which is arranged, the sliding chute 18 which the sliding control of the sliding chute 18 is arranged, the sliding chute 21 which is arranged, the sliding chute 21 which the sliding chute 21 is arranged, the rotating ring 33 is rotatably connected with the bottom of the control cylinder 18, the limiting ring 32 is fixedly sleeved in the control cylinder 18, the limiting ring 32 is located on the upper side of the moving ring 30 and is in contact connection with the moving ring 30, the second spring 31 and the limiting ring 32 in the control cylinder 18 are used for completing the limiting and fixing operation on the moving ring 30, and further the limiting and fixing operation on the control rod 10 is completed.
A method for removing boron impurities in metallurgical-grade silicon in a submerged arc furnace 1 comprises the following steps:
s1, firstly, taking out a piston block 9 from a feeding hole 7, putting metallurgical silicon into a submerged arc furnace 1, starting a heating electrode 3, and smelting until all raw material silicon is changed into silicon liquid;
s2, mixing the Na 2 CO 3 -SiO 2 Adding slag agent into the silicon liquid through a feed inlet 7 and a feed pipe 8, preserving heat, and adding Na 2 CO 3 -SiO 2 The weight ratio of the slag agent to the metallurgical silicon is 45; the Na is 2 CO 3 -SiO 2 Na in slag agent 2 CO 3 The mass percentage of the silicon dioxide is 64 to 69.5 percent, and the balance is SiO 2 (ii) a The heat preservation temperature is 1800-1950 ℃; the heat preservation time is 20-30 minutes;
s3, mixing the evenly mixed CaO-SiO 2 Slag agent is added into the silicon liquid through a feed inlet 7 and a feed pipe 8 and is subjected to heat preservation, and CaO-SiO 2 The weight ratio of the slag agent to the metallurgical silicon is 87; the CaO-SiO 2 The slag agent CaO accounts for 70 percent in percentage by mass74 percent, and the balance being SiO 2 (ii) a The heat preservation temperature is 1800-1900 ℃; the heat preservation time is 30-40 minutes;
s4, after the integral reaction is finished, the control rod 10 is moved downwards, the control rod 10 drives the moving ring 30 to move downwards, the moving ring 30 compresses the second spring 31, the control rod 10 can also drive the second gear 11 to move downwards, the second gear 11 is in contact with the third gear 12 and drives the third gear 12 to move downwards, the third gear 12 compresses the first spring 13 until the third gear 12 is disconnected from the inner gear ring 24 and the inner gear ring 24 is meshed with the second gear 11, the control rod 10 is rotated, the control rod 10 drives the inner gear ring 24 to rotate through the second gear 11, the control ring 19 is moved downwards under the action of the control wire 26 and the control ring 19, until the control ring 19 moves to the upper side of a slag boundary layer, the slag liquid is extracted by the hose 23 and the corresponding press machine, the operation is repeated, the silicon liquid is extracted, and raw materials of silicon and Na are subjected to silicon and Na 2 CO 3 -SiO 2 Slag agent and CaO-SiO 2 In the adding process of the slag agent, the control rod 10 is rotated, the control rod 10 drives the rotating rod 4 to rotate through the second gear 11 and the first gear 6, the rotating rod 4 drives the stirring rod 5 to rotate, corresponding stirring operation is carried out, and the mixing time is shortened.
In the invention, firstly, the piston block 9 is taken out from the feed inlet 7, metallurgical silicon is put into the submerged arc furnace 1, the heating electrode 3 is started, and smelting is started, which is the prior art and is not described in detail, until all raw material silicon is changed into silicon liquid; mixing the mixed Na 2 CO 3 -SiO 2 Adding slag agent into silicon liquid through a feed inlet 7 and a feed pipe 8, and keeping the temperature, wherein Na 2 CO 3 -SiO 2 The weight ratio of the slag agent to the metallurgical silicon is 45; na of (2) 2 CO 3 -SiO 2 Na in slag agent 2 CO 3 The mass percentage of the silicon dioxide is 64 percent to 69.5 percent, and the balance is SiO 2 (ii) a The heat preservation temperature is 1800-1950 ℃; the heat preservation time is 20-30 minutes; mixing the evenly mixed CaO-SiO 2 The slag agent is put into the silicon liquid through the feed inlet 7 and the feed pipe 8 and is insulated, wherein CaO-SiO 2 The weight ratio of the slag agent to the metallurgical silicon is 87; caO-SiO 2 The weight percentage content of CaO in slag agent70 to 74 percent of the total weight of the composition, and the balance of SiO 2 (ii) a The heat preservation temperature is 1800-1900 ℃; the heat preservation time is 30-40 minutes; after the whole reaction is completed, the control rod 10 is moved downwards, the control rod 10 drives the moving ring 30 to move downwards, the moving ring 30 compresses the second spring 31, the control rod 10 can also drive the second gear 11 to move downwards, the second gear 11 is in contact with the third gear 12 and drives the third gear 12 to move downwards, the third gear 12 compresses the first spring 13 until the third gear 12 is disconnected from the inner gear ring 24 and the inner gear ring 24 is meshed with the second gear 11, the control rod 10 is rotated, the control rod 10 drives the inner gear ring 24 to rotate through the second gear 11, the control ring 19 is moved downwards under the self-gravity action of the control wire 26 and the control ring 19 until the control ring 19 moves to the upper side of the slag boundary layer, the slag liquid is pumped out by using the hose 23 and a corresponding press machine, the operation is repeated, the silicon liquid is taken out, and the raw materials of silicon and Na are carried out 2 CO 3 -SiO 2 Slag agent and CaO-SiO 2 In the adding process of the slag agent, the control rod 10 is rotated, the control rod 10 drives the rotating rod 4 to rotate through the second gear 11 and the first gear 6, the rotating rod 4 drives the stirring rod 5 to rotate, corresponding stirring operation is carried out, the mixing time is reduced, and B impurities in the silicon liquid are diffused to a slag-silicon interface and are Na-doped 2 CO 3 Decomposition product Na 2 O, an alkaline earth metal oxide CaO, and free [ O ] can be provided]SiO of (2) 2 And (4) oxidizing. Due to boron oxides BO, B 2 O 3 、B 2 O、BO 2 、B 2 O 2 And the lower Gibbs free energy exists in a slag system, so that boron oxide tends to enter slag liquid, and B impurities in the silicon liquid are removed. In addition, due to Na formation 2 O-SiO 2 The density of the slag liquid is less than that of the silicon liquid, so the slag liquid is positioned above the silicon liquid; when the evenly mixed CaO-SiO is added 2 CaO-Na is formed after slag agent 2 O-SiO 2 The slag system, the density of the slag liquid is greater than that of the silicon liquid; convection is formed between slag silicon liquid floating on slag silicon liquid sinking in the slag silicon liquid, the contact area between the slag silicon liquid is increased, the dynamic condition of mass transfer of impurities between the slag silicon liquid and the slag silicon liquid is improved, the integral boron removal effect is improved, the slag silicon liquid is layered after the reaction reaches balance, and ore is separatedAfter the discharge port of the heating furnace (namely the control ring and the hose) is opened, the slag liquid flows out firstly, thereby realizing the separation of the slag and the silicon liquid.
The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be considered as the technical solutions and the inventive concepts of the present invention within the technical scope of the present invention.
Claims (10)
1. The utility model provides a get rid of device of boron impurity in metallurgical grade silicon in ore smelting furnace, includes hot stove in ore smelting (1), its characterized in that, bottom fixed connection is equipped with heating electrode (3) in hot stove in ore smelting (1), fixed connection is equipped with heat transfer board (2) in hot stove in ore smelting (1), upside and the matching of heating electrode (3) that heat transfer board (2) are located heating electrode (3) correspond the setting, upward the left side is equipped with feed inlet (7) in hot stove in ore smelting (1), feed inlet (7) downside fixed connection is equipped with inlet pipe (8), the matching cover is equipped with piston block (9) in feed inlet (7), piston block (9) run through in feed inlet (7) setting, upside rotation connection is equipped with dwang (4) in hot stove in ore smelting (1), dwang (4) are located the right side setting of feed inlet (7), lateral wall symmetry fixed connection of dwang (4) is equipped with a plurality of dwang puddlers (5), fixed cover still is equipped with first gear (6) in the outside of ore smelting (4), first gear (6) are located the upside setting of a plurality of puddlers (5), be equipped with ore smelting (10) control rod (10) in ore smelting (10) control rod (10), second gear (11) and first gear (6) meshing connection set up, it is equipped with fixed connection and is equipped with hose (23) to be equipped with in hot stove in the ore deposit (1), hose (23) run through in hot stove in the ore deposit (1) setting, hose (23) are located hot stove in the ore deposit (1) one end fixed connection and are equipped with control ring (19), be equipped with the mobile control device of control ring (19) in the hot stove in the ore deposit (1).
2. An apparatus according to claim 1 for removing boron impurities from metallurgical grade silicon in a submerged arc furnace, it is characterized in that the mobile control device comprises a fixed plate (14) fixedly connected and arranged in the submerged arc furnace (1), the fixing plate (14) is arranged at the lower side of the second gear (11), an inner gear ring (24) is arranged on the upper side of the fixing plate (14), an annular groove (28) is arranged on the upper side of the fixing plate (14), two sliding rods (29) are symmetrically and slidably connected in the annular groove (28), the two sliding rods (29) penetrate through the annular groove (28) and the inner gear ring (24) to be fixedly connected, the inner gear ring (24) and the second gear (11) are correspondingly matched, a third gear (12) which is the same as the second gear (11) is sleeved in the inner gear ring (24), a first spring (13) is fixedly connected with the lower side of the third gear (12), the other side of the first spring (13) is fixedly connected with the fixing plate (14), a wire guide groove (25) is arranged on the outer side of the inner gear ring (24), a control wire (26) is wound and connected in the wire guide groove (25), the control wire (26) is arranged by penetrating through the wire guide groove (25), the upper side of the control ring (19) is fixedly connected with a pull ring (20), the control line (26) and the pull ring (20) are fixedly connected.
3. The device for removing the boron impurities in the metallurgical grade silicon in the submerged arc furnace according to the claim 2, characterized in that a first fixing ring (27) is fixedly connected to the right side in the submerged arc furnace (1), a second fixing ring (17) is fixedly connected to the upper side in the submerged arc furnace (1), and the control wire (26) is arranged to penetrate through the first fixing ring (27) and the second fixing ring (17).
4. The device for removing boron impurities in metallurgical-grade silicon in the ore smelting furnace according to claim 2, characterized in that the fixing plate (14) is provided with a square hole (15) at the upper side, a square rod (16) is slidably sleeved in the square hole (15), the square rod (16) penetrates through the square hole (15), and the square rod (16) and the third gear (12) are fixedly connected.
5. The device for removing the boron impurities in the metallurgical-grade silicon in the submerged arc furnace according to the claim 1, characterized in that the inner side wall of the submerged arc furnace (1) is provided with a sliding chute (21), the sliding chute (21) is internally and slidably connected with a sliding block (22), and the sliding block (22) is fixedly connected with a control ring (19) through the sliding chute (21).
6. The device for removing boron impurities in metallurgical-grade silicon in the submerged arc furnace according to claim 1, wherein the control rod (10) is positioned in the submerged arc furnace (1) and sleeved with a control cylinder (18), the control cylinder (18) is positioned on the upper side of the second gear (11), the control rod (10) is positioned in the control cylinder (18) and sleeved with a moving ring (30), the lower side of the moving ring (30) is fixedly connected with a second spring (31), the other side of the second spring (31) is fixedly connected with a rotating ring (33), the rotating ring (33) is rotatably connected with the bottom of the control cylinder (18), the control cylinder (18) is sleeved with a limiting ring (32), and the limiting ring (32) is positioned on the upper side of the moving ring (30) and in contact connection with the moving ring (30).
7. A method for removing boron impurities in metallurgical-grade silicon in a submerged arc furnace is characterized by comprising the following steps:
s1, firstly, taking out a piston block (9) from a feeding hole (7), putting metallurgical silicon into a submerged arc furnace (1), starting a heating electrode (3) and smelting until all raw material silicon is changed into silicon liquid;
s2, mixing the Na 2 CO 3 -SiO 2 Slag agents are put into the silicon liquid through a feeding hole (7) and a feeding pipe (8) and are kept warm;
s3, mixing the evenly mixed CaO-SiO 2 Slag agents are put into the silicon liquid through a feeding hole (7) and a feeding pipe (8) and are kept warm;
s4, after the integral reaction is finished, the control rod (10) is moved downwards, the control rod (10) drives the moving ring (30) to move downwards, the moving ring (30) compresses the second spring (31), the control rod (10) can also drive the second gear (11) to move downwards, the second gear (11) is in contact with the third gear (12) and drives the third gear (12) to move downwards, the third gear (12) compresses the first spring (13) until the third gear (12) is disconnected with the inner gear ring (24), the inner gear ring (24) is meshed with the second gear (11) and connected, the control rod (10) is rotated, the control rod (10) drives the inner gear ring (24) to rotate through the second gear (11), the control ring (19) is moved downwards under the self-gravity action of the control wire (26) and the control ring (19), until the control ring (19) moves to the upper side of a slag boundary layer, the slag liquid is extracted through the hose (23) and then is repeatedly extracted.
8. A method according to claim 7, characterized in that the raw material silicon, na is processed 2 CO 3 -SiO 2 Slag agent and CaO-SiO 2 In the adding process of the slag agent, the control rod (10) is rotated, the control rod (10) drives the rotating rod (4) to rotate through the second gear (11) and the first gear (6), the rotating rod (4) drives the stirring rod (5) to rotate, corresponding stirring operation is carried out, and the mixing time is shortened.
9. The method for removing boron impurities in metallurgical grade silicon in ore furnace according to claim 7, wherein Na in step S2 2 CO 3 -SiO 2 The weight ratio of the slag agent to the metallurgical silicon is 45; said Na 2 CO 3 -SiO 2 Na in slag agent 2 CO 3 The mass percentage of the silicon dioxide is 64 percent to 69.5 percent, and the balance is SiO 2 (ii) a The heat preservation temperature is 1800-1950 ℃; the heat preservation time is 20-30 minutes.
10. The method for removing boron in a submerged arc furnace according to claim 7, wherein CaO-SiO in the step S3 2 The weight ratio of the slag agent to the metallurgical silicon is 87; the CaO-SiO 2 The weight percentage content of the slag agent CaO is 70 percent to 74 percent, and the rest is SiO 2 (ii) a The heat preservation temperature is 1800-1900 ℃; the heat preservation time is 30-40 minutes.
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