Impurity adsorption device for polycrystalline silicon process

Abstract

The utility model relates to the technical field of polycrystalline silicon, and discloses an impurity adsorption device for a polycrystalline silicon process. A heat regeneration mechanism comprises a tank body and a replacement assembly installed on one side of the tank body, a tank cover is welded to the upper end of the tank body, a partition net is arranged at the upper end of an inner cavity of the tank body, a partition plate is installed in the tank body, a first annular heating pipe is installed on the upper side of the partition plate, and a second annular heating pipe is installed at the lower end of the inner cavity of the tank body. An inert gas connecting pipe is fixedly connected to one side of the tank body, molecular sieve particles used for adsorbing impurities in the adsorption column are sucked out through a replacement assembly, inert gas is introduced into one end of the inert gas connecting pipe, a first annular heating pipe and a second annular heating pipe are opened, the impurities are removed through heating, and waste gas flows into a tail gas treatment mechanism; the molecular sieve is prevented from being blown into the tail gas treatment mechanism by utilizing the separation net, and then the molecular sieve particles after thermal regeneration are sent back to the adsorption column, so that the impurity adsorption efficiency of the molecular sieve for adsorption in the adsorption column is stable.

Description

Technical Field

[0001] The utility model relates to the technical field of polysilicon, in particular to an impurity adsorption device for a polysilicon process. Background Art

[0002] Polysilicon is a semiconductor material with a gray metallic luster and a density of 2.32-2.34 g / cm 3 Its hardness lies between that of germanium and quartz. It is brittle at room temperature and easily breaks when cut. Polycrystalline silicon exhibits a certain degree of plasticity at high temperatures, with a melting point of 1410°C. Its conductivity lies between that of conductors and insulators, making it the primary raw material for solar cells. With the global emphasis on renewable energy and the continued development of the solar photovoltaic industry, the market for polycrystalline silicon is promising.

[0003] At present, the existing process in the polysilicon industry is that the output from the coarse fractionation tower of the cold hydrogenation process directly enters the distillation process for impurity treatment. The distillation process operates at the set temperature and pressure. In recent years, companies have paid more and more attention to the exploration of reducing the cost of raw materials. The use of coarser silicon powder has become an industry trend, which indirectly leads to an increase in the load of the cold hydrogenation process and an increase in impurities brought into the material, which in turn leads to an increase in the processing load of the distillation impurity treatment tower. The impurities are not fully distilled and are brought into the subsequent system, resulting in the accumulation of impurities in the distillation system.

[0004] In the above process, selective molecular sieves are often used to adsorb impurities containing B and P to achieve the impurity removal effect. After long-term use, if the impurities in the molecular sieve cannot be removed in time, the impurity removal effect of the molecular sieve will be reduced, affecting the product quality of polysilicon.

[0005] Therefore, in order to solve such problems, we propose an impurity adsorption device for polysilicon process. Utility Model Content

[0006] The purpose of the utility model is to provide an impurity adsorption device for a polysilicon process, aiming to solve the problem in the above-mentioned background technology that the impurity removal effect of the existing selective molecular sieve used for impurity removal is reduced after long-term use, which affects product quality.

[0007] In order to achieve the above-mentioned purpose, the utility model adopts the following technical solutions: an impurity adsorption device for a polysilicon process, comprising a reaction tower and an exhaust gas treatment mechanism fixedly connected to the upper end of the reaction tower, the end of the reaction tower away from the exhaust gas treatment mechanism is fixedly connected to a tower kettle extraction mechanism, the output end of the tower kettle extraction mechanism is provided with an adsorption column, and one side of the adsorption column is provided with a thermal regeneration mechanism; the thermal regeneration mechanism comprises a tank body and a replacement assembly installed on one side of the tank body, a tank cover is welded to the upper end of the tank body, the upper end of the tank cover is fixedly connected to one end of the exhaust gas treatment mechanism, a partition is provided at the upper end of the inner cavity of the tank body, the partition is fixedly connected to the tank cover, a partition is installed inside the tank body, an annular heating pipe 1 is installed on the upper side of the partition, an annular heating pipe 2 is installed at the lower end of the inner cavity of the tank body, and an inert gas connecting pipe is fixedly connected to one side of the lower end of the tank body.

[0008] Preferably, the replacement assembly includes a solenoid valve and a connecting pipe fixedly connected to one side of the solenoid valve, one end of the solenoid valve is fixedly connected to the adsorption column, the end of the connecting pipe away from the solenoid valve is fixedly connected to a bidirectional pump, and the other end of the bidirectional pump is fixedly connected to the tank body.

[0009] Preferably, the reaction tower includes a tower body and a tower cover welded to the upper end of the tower body, the upper end of the tower cover is fixedly connected to one end of the exhaust gas treatment mechanism, the lower end of the tower body is welded with a tower kettle, and one side of the tower kettle is fixedly connected to the input end of the tower kettle extraction mechanism.

[0010] Preferably, the exhaust gas treatment mechanism includes exhaust pipe 1 and exhaust pipe 2 fixedly connected to one end of exhaust pipe 1, exhaust pipe 1 is fixedly connected to the upper end of the tower cover, one side of exhaust pipe 2 is fixedly connected to exhaust pipe 3, the lower end of exhaust pipe 3 is fixedly connected to the upper end of the tank cover, the end of exhaust pipe 2 away from exhaust pipe 1 is fixedly connected to the exhaust condenser, and the end of the exhaust condenser away from exhaust pipe 2 is fixedly connected to the exhaust treatment main pipe.

[0011] Preferably, the tower bottom extraction mechanism includes a tower bottom extraction pipe and a tower bottom extraction pump fixedly connected to the output end of the tower bottom extraction pipe. The tower bottom extraction pipe extends into the interior of the tower bottom. The end of the tower bottom extraction pump away from the tower bottom extraction pipe is fixedly connected to a delivery pipe 1. The output end of the delivery pipe 1 is provided with a tower bottom condenser pipe. The end of the tower bottom condenser pipe away from the delivery pipe 1 is fixedly connected to a delivery pipe 2. The output end of the tower bottom delivery pipe 2 is fixedly connected to the input end of the adsorption column.

[0012] Preferably, the adsorption column includes a column body and a column cover welded to the upper end of the column body, the upper end of the column cover is fixedly connected to the output end of the tower kettle delivery pipe 2, a filter screen 1 is fixedly connected to the inner wall of the column body, an adsorption rod is provided at the center of the filter screen 1, a filter screen 2 is provided on the side of the adsorption rod away from the filter screen 1, the adsorption rod passes through the filter screen 1 and the filter screen 2, the filter screen 2 is fixedly connected to the inner wall of the column body, a column bottom is welded to the lower end of the column body, and the lower end of the column bottom is fixedly connected to the finished product delivery pipe.

[0013] The utility model has the following beneficial effects:

[0014] In the utility model, a heat regeneration mechanism is provided on one side of the adsorption column; the heat regeneration mechanism includes a tank body and a replacement assembly installed on one side of the tank body, a tank cover is welded on the upper end of the tank body, a partition is provided on the upper end of the tank inner cavity, a partition is installed inside the tank body, an annular heating pipe 1 is installed on the upper side of the partition, and an annular heating pipe 2 is installed at the lower end of the tank inner cavity, and an inert gas connecting pipe is fixedly connected to one side of the tank body. The molecular sieve particles used for adsorbing impurities inside the adsorption column are sucked out by using the replacement assembly, inert gas is introduced at one end of the inert gas connecting pipe, the annular heating pipe 1 and the annular heating pipe 2 are opened, impurities are removed by heating, and the waste gas flows into the exhaust gas treatment mechanism, and the partition is used to prevent the molecular sieve from being blown into the exhaust gas treatment mechanism, and the molecular sieve particles after heat regeneration are returned to the adsorption column, thereby ensuring the stable efficiency of the molecular sieve in the adsorption column in adsorbing impurities. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a three-dimensional schematic diagram of an impurity adsorption device for a polysilicon process proposed by the present invention;

[0016] Figure 2 This is a three-dimensional schematic diagram of a reaction tower in an impurity adsorption device for a polysilicon process proposed by the present invention;

[0017] Figure 3 This is a three-dimensional schematic diagram of an exhaust gas treatment mechanism in an impurity adsorption device for a polysilicon process proposed by the present invention;

[0018] Figure 4 This is a three-dimensional schematic diagram of a tower kettle extraction mechanism in an impurity adsorption device for a polysilicon process proposed by the present invention;

[0019] Figure 5 This is a schematic plan view of an adsorption column in an impurity adsorption device for a polysilicon process proposed by the present invention;

[0020] Figure 6 This is a schematic plan view of a heat regeneration mechanism in an impurity adsorption device for a polysilicon process proposed by the present invention;

[0021] Figure 7 The present invention is a three-dimensional schematic diagram of a replacement component in an impurity adsorption device for a polysilicon process.

[0022] Legend:

[0023] 1. Reaction tower; 11. Tower body; 12. Tower cover; 13. Tower reactor; 2. Tail gas treatment mechanism; 21. Tail gas pipe 1; 22. Tail gas pipe 2; 23. Tail gas pipe 3; 24. Tail gas condenser; 25. Tail gas treatment main pipe; 3. Tower reactor extraction mechanism; 31. Tower reactor extraction pipe; 32. Tower reactor extraction pump; 33. Delivery pipe 1; 34. Tower reactor condenser pipe; 35. Delivery pipe 2; 4. Adsorption column; 41. Column Body; 42. Column cover; 43. Filter screen 1; 44. Adsorption rod; 45. Filter screen 2; 46. Column bottom; 47. Finished product delivery pipe; 5. Heat regeneration mechanism; 51. Tank body; 52. Replacement assembly; 521. Solenoid valve; 522. Connecting pipe; 523. Two-way pump; 53. Tank cover; 54. Partition screen; 55. Partition; 56. Annular heating pipe 1; 57. Annular heating pipe 2; 58. Inert gas connecting pipe. DETAILED DESCRIPTION

[0024] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0025] In the description of the present invention, it should be noted that the terms "center," "up," "down," "left," "right," "vertical," "horizontal," "inside," "outside," etc., indicating positions or positional relationships, are based on the positions or positional relationships shown in the accompanying drawings and are used only to facilitate the description of the present invention and simplify the description. They do not indicate or imply that the devices or components referred to must have a specific position, be constructed and operate in a specific position. Therefore, they should not be understood as limiting the present invention. The terms "first," "second," and "third" are used for descriptive purposes only and should not be understood as indicating or implying relative importance. In addition, unless otherwise expressly specified or limited, the terms "installed," "connected," and "connected" should be understood in a broad sense. For example, they can be fixedly connected, detachably connected, or integrally connected. They can be mechanically connected or electrically connected. They can be directly connected, indirectly connected through an intermediate medium, or can be internal communication between two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0026] See also Figure 1 、 Figure 6The utility model provides an embodiment: an impurity adsorption device for a polysilicon process, comprising a reaction tower 1 and an exhaust gas treatment mechanism 2 fixedly connected to the upper end of the reaction tower 1, a tower kettle extraction mechanism 3 fixedly connected to one end of the reaction tower 1 away from the exhaust gas treatment mechanism 2, an adsorption column 4 is provided at the output end of the tower kettle extraction mechanism 3, a heat regeneration mechanism 5 is provided on one side of the adsorption column 4; the heat regeneration mechanism 5 comprises a tank body 51 and a replacement component 52 installed on one side of the tank body 51, a tank cover 53 is welded to the upper end of the tank body 51, the upper end of the tank cover 53 is fixedly connected to one end of the exhaust gas treatment mechanism 2, a partition 54 is provided at the upper end of the inner cavity of the tank body 51, the partition 54 is fixedly connected to the tank cover 53, and a heat regeneration mechanism 52 is provided inside the tank body 51. A partition 55 is installed, and an annular heating pipe 1 56 is installed on the upper side of the partition 55. An annular heating pipe 2 57 is installed at the lower end of the inner cavity of the tank body 51. An inert gas connecting pipe 58 is fixedly connected to one side of the lower end of the tank body 51. The molecular sieve particles used to adsorb impurities in the adsorption column 4 are sucked out by using the replacement component 52. Inert gas is introduced into one end of the inert gas connecting pipe 58, and the annular heating pipe 1 56 and the annular heating pipe 2 57 are opened to heat and remove impurities. The waste gas flows into the exhaust gas treatment mechanism 2, and the partition net 54 is used to prevent the molecular sieve from being blown into the exhaust gas treatment mechanism 2. The molecular sieve particles after thermal regeneration are then returned to the adsorption column 4, ensuring that the efficiency of the adsorption molecular sieve in the adsorption column 4 in adsorbing impurities is stable.

[0027] See also Figure 7 The replacement component 52 includes a solenoid valve 521 and a connecting pipe 522 fixedly connected to one side of the solenoid valve 521. One end of the solenoid valve 521 is fixedly connected to the adsorption column 4. The end of the connecting pipe 522 away from the solenoid valve 521 is fixedly connected to a two-way pump 523. The other end of the two-way pump 523 is fixedly connected to the tank body 51. When the adsorbent in the adsorption column 4 needs to be replaced, the solenoid valve 521 is opened, the two-way pump 523 is turned on, and all the used adsorbent in the adsorption column 4 is sucked out. The solenoid valve 521 is closed, and the adsorbent is thermally regenerated by the thermal regeneration mechanism 5. Then, the solenoid valve 521 is opened, the conveying direction of the two-way pump 523 is changed, and the thermally regenerated adsorbent is conveyed into the adsorption column 4.

[0028] See also Figure 2 The reaction tower 1 includes a tower body 11 and a tower cover 12 welded to the upper end of the tower body 11. The upper end of the tower cover 12 is fixedly connected to one end of the exhaust gas treatment mechanism 2. The lower end of the tower body 11 is welded with a tower kettle 13. One side of the tower kettle 13 is fixedly connected to the input end of the tower kettle extraction mechanism 3. The raw materials participate in the reaction inside the reaction tower 1, the exhaust gas flows to the exhaust gas treatment mechanism 2, and the products are extracted through the tower kettle extraction mechanism 3.

[0029] See also Figure 3The exhaust gas treatment mechanism 2 includes an exhaust pipe 21 and an exhaust pipe 22 fixedly connected to one end of the exhaust pipe 1 21. The exhaust pipe 1 21 is fixedly connected to the upper end of the tower cover 12. One side of the exhaust pipe 2 22 is fixedly connected to the exhaust pipe 3 23. The lower end of the exhaust pipe 3 23 is fixedly connected to the upper end of the tank cover 53. The end of the exhaust pipe 2 22 away from the exhaust pipe 1 21 is fixedly connected to the exhaust condenser 24. The end of the exhaust condenser 24 away from the exhaust pipe 2 22 is fixedly connected to the exhaust treatment main pipe 25. The exhaust gas generated in the reaction tower 1 is merged with the exhaust gas generated in the heat regeneration mechanism 5, enters the exhaust pipe 2 22, and is collected and treated by the exhaust treatment main pipe 25 after condensation treatment by the exhaust condenser 24.

[0030] See also Figure 4 The tower bottom extraction mechanism 3 includes a tower bottom extraction pipe 31 and a tower bottom extraction pump 32 fixedly connected to the output end of the tower bottom extraction pipe 31. The tower bottom extraction pipe 31 extends into the interior of the tower bottom 13. The end of the tower bottom extraction pump 32 away from the tower bottom extraction pipe 31 is fixedly connected to a delivery pipe 1 33. The output end of the delivery pipe 1 33 is provided with a tower bottom condenser pipe 34. The end of the tower bottom condenser pipe 34 away from the delivery pipe 1 33 is fixedly connected to a delivery pipe 2 35. The output end of the tower bottom delivery pipe 2 35 is fixedly connected to the input end of the adsorption column 4. The product is extracted from the tower bottom 13 by the tower bottom extraction pump 32, and after condensation through the tower bottom condenser pipe 34, it enters the adsorption column 4 for impurity removal.

[0031] See also Figure 5 The adsorption column 4 includes a column body 41 and a column cover 42 welded to the upper end of the column body 41, the upper end of the column cover 42 is fixedly connected to the output end of the tower bottom delivery pipe 2 35, and a filter screen 1 43 is fixedly connected to the inner wall of the column body 41. An adsorption rod 44 is arranged at the center of the filter screen 1 43, and a filter screen 2 45 is arranged on the side of the adsorption rod 44 away from the filter screen 1 43. The adsorption rod 44 passes through the filter screen 1 43 and the filter screen 2 45, and the filter screen 2 45 is fixedly connected to the inner wall of the column body 41. A column bottom 46 is welded to the lower end of the column body 41, and the lower end of the column bottom 46 is fixedly connected to the finished product delivery pipe 47. The tower bottom condensate containing impurities passes through the boron selective molecular sieve on the filter screen 1 43 and the phosphorus selective molecular sieve arranged on the filter screen 2 45, and cooperates with the adsorption rod 44 made of a metal organic framework material MOFS to remove impurities containing boron and phosphorus, and then flows into the distillation storage tank through the finished product delivery pipe 47.

[0032] Working principle: The product is extracted from the tower bottom 13 through the tower bottom extraction pump 32, condensed through the tower bottom condenser 34 and then enters the adsorption column 4 for impurity removal. The tower bottom condensate containing impurities passes through the boron selective molecular sieve on the filter screen 1 43 and the phosphorus selective molecular sieve set on the filter screen 2 45, and cooperates with the adsorption rod 44 made of a metal organic framework material MOFS to remove impurities containing boron and phosphorus, and flows into the distillation storage tank through the finished product delivery pipe 47; when the adsorbent in the adsorption column 4 needs to be replaced, the solenoid valve 521 is opened, the two-way pump 523 is turned on, and all the used adsorbent in the adsorption column 4 is sucked out, the solenoid valve 521 is closed, and inert gas is introduced into one end of the inert gas connecting pipe 58, the annular heating pipe 1 56 and the annular heating pipe 2 57 are opened, and impurities are removed by heating. The partition 54 is used to prevent the molecular sieve from being blown into the tail gas pipe 3 23, and then the solenoid valve 521 is opened to change the delivery direction of the two-way pump 523, and the thermally regenerated adsorbent is delivered into the adsorption column 4.

[0033] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or make equivalent replacements for some of the technical features therein. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. An impurity adsorption device for a polysilicon process, comprising a reaction tower (1) and an exhaust gas treatment mechanism (2) fixedly connected to the upper end of the reaction tower (1), an end of the reaction tower (1) away from the exhaust gas treatment mechanism (2) fixedly connected to a tower bottom extraction mechanism (3), an output end of the tower bottom extraction mechanism (3) provided with an adsorption column (4), characterized in that: A heat regeneration mechanism (5) is provided on one side of the adsorption column (4); the heat regeneration mechanism (5) includes a tank body (51) and a replacement assembly (52) installed on one side of the tank body (51); a tank cover (53) is welded to the upper end of the tank body (51); the upper end of the tank cover (53) is fixedly connected to one end of the tail gas treatment mechanism (2); a partition (54) is provided at the upper end of the inner cavity of the tank body (51); a partition (55) is installed inside the tank body (51); an annular heating pipe (56) is installed on the upper side of the partition (55); an annular heating pipe (57) is installed at the lower end of the inner cavity of the tank body (51); and an inert gas connecting pipe (58) is fixedly connected to one side of the tank body (51).

2. The impurity adsorption device for a polysilicon process according to claim 1, characterized in that: The replacement assembly (52) comprises a solenoid valve (521) and a connecting pipe (522) fixedly connected to one side of the solenoid valve (521); one end of the solenoid valve (521) is fixedly connected to the adsorption column (4); one end of the connecting pipe (522) away from the solenoid valve (521) is fixedly connected to a bidirectional pump (523); and the other end of the bidirectional pump (523) is fixedly connected to the tank body (51).

3. The impurity adsorption device for a polysilicon process according to claim 1, characterized in that: The reaction tower (1) comprises a tower body (11) and a tower cover (12) welded to the upper end of the tower body (11); the upper end of the tower cover (12) is fixedly connected to one end of the tail gas treatment mechanism (2); a tower kettle (13) is welded to the lower end of the tower body (11); and one side of the tower kettle (13) is fixedly connected to the input end of the tower kettle extraction mechanism (3).

4. The impurity adsorption device for a polysilicon process according to claim 3, characterized in that: The exhaust gas treatment mechanism (2) includes an exhaust pipe (21) and an exhaust pipe (22) fixedly connected to one end of the exhaust pipe (21), the exhaust pipe (21) is fixedly connected to the upper end of the tower cover (12), one side of the exhaust pipe (22) is fixedly connected to the exhaust pipe (23), the lower end of the exhaust pipe (23) is fixedly connected to the upper end of the tank cover (53), the end of the exhaust pipe (22) away from the exhaust pipe (21) is fixedly connected to the exhaust condenser (24), and the end of the exhaust condenser (24) away from the exhaust pipe (22) is fixedly connected to the exhaust treatment main pipe (25).

5. The impurity adsorption device for polysilicon process according to claim 3, characterized in that: The tower bottom extraction mechanism (3) comprises a tower bottom extraction pipe (31) and a tower bottom extraction pump (32) fixedly connected to the output end of the tower bottom extraction pipe (31). The tower bottom extraction pipe (31) extends into the interior of the tower bottom (13). The end of the tower bottom extraction pump (32) away from the tower bottom extraction pipe (31) is fixedly connected to a delivery pipe 1 (33). The output end of the delivery pipe 1 (33) is provided with a tower bottom condenser pipe (34). The end of the tower bottom condenser pipe (34) away from the delivery pipe 1 (33) is fixedly connected to a delivery pipe 2 (35). The output end of the tower bottom delivery pipe 2 (35) is fixedly connected to the input end of the adsorption column (4).

6. The impurity adsorption device for polysilicon process according to claim 5, characterized in that: The adsorption column (4) comprises a column body (41) and a column cover (42) welded to the upper end of the column body (41); the upper end of the column cover (42) is fixedly connected to the output end of the second tower kettle delivery pipe (35); a filter screen (43) is fixedly connected to the inner wall of the column body (41); an adsorption rod (44) is provided at the center of the filter screen (43); a filter screen (45) is provided on the side of the adsorption rod (44) away from the filter screen (43); the adsorption rod (44) passes through the filter screen (43) and the filter screen (45); the filter screen (45) is fixedly connected to the inner wall of the column body (41); a column bottom (46) is welded to the lower end of the column body (41); and the lower end of the column bottom (46) is fixedly connected to the finished product delivery pipe (47).

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