Conveying system for recovering chlorosilane material and directly supplying chlorosilane material to rectification section

Abstract

The utility model discloses a conveying system for directly supplying recovered chlorosilane materials to a rectification section, which belongs to the technical field of polycrystalline silicon production equipment, and comprises a recovery storage tank, a transfer tank, a rectification tower and a controller, the recovery storage tank is connected with a pump I through a pipeline I, and the pump I is directly connected with a feed port of the rectification tower through a main pipe; the pump I is connected with the transfer tank through a pipeline II, a regulating valve I is arranged on the pipeline II, a material outlet of the transfer tank is connected with the pump II and then converged into the main pipe through a pipeline III, a liquid level sensor is arranged on the recovery storage tank, and the controller is in control connection with the liquid level sensor and the regulating valve I. The conveying system for directly supplying the recovered chlorosilane material to the rectification section is provided. The recovered materials are directly conveyed to the rectification section from the recovery storage tank of the recovery section without being transferred in a tank area, so that the system operation cost is reduced, and the safe and stable operation of the rectification section is ensured.

Description

Technical Field

[0001] The utility model belongs to the technical field of polysilicon production equipment, and in particular relates to a conveying system for recovering chlorosilane materials and directly supplying them to a distillation section. Background Art

[0002] In the traditional polysilicon production process, the material extracted from the kettle of the recovery and analysis tower undergoes a first-level heat exchange with the material in the absorption tower, then enters a circulating water cooler to be cooled to 60°C, and is then transported to the tank area through a shielded pump. Finally, it is transported to the recovery distillation device for separation and purification through a shielded pump in the tank area.

[0003] The above-mentioned whole material conveying process mainly has the following problems:

[0004] 1. Since the entire transportation process involves many devices (tank areas) and pipelines, it is easy to introduce process impurities, which has a certain impact on the final product quality;

[0005] 2. The entire conveying process requires the use of multiple shielded pumps, and each shielded pump has a high operating pressure and consumes a lot of electricity, which makes the entire conveying process very costly. Utility Model Content

[0006] The utility model aims to solve the above technical problems and proposes a conveying system for recovering chlorosilane materials and directly supplying them to a distillation section. It is considered that the recovered materials do not need to be transferred through a tank area, but can be directly sent from the recovery storage tank of the recovery section to the distillation section, thereby reducing the system operation cost and ensuring the safe and stable operation of the distillation section.

[0007] In order to achieve the above-mentioned invention object, the technical solution of the utility model is as follows:

[0008] A conveying system for recovering chlorosilane materials and directly supplying them to a distillation section comprises a recovery tank, a transfer tank, a distillation tower and a controller, wherein the recovery tank is connected to a pump I through a pipeline I, the pump I is directly connected to a feed port of the distillation tower through a main pipe, the pump I is connected to the transfer tank through a pipeline II, a regulating valve I is arranged on the pipeline II, a material outlet of the transfer tank is connected to the pump II and then merged into the main pipe through a pipeline III, a liquid level sensor is arranged on the recovery tank, and the controller is respectively controlled and connected to the liquid level sensor and the regulating valve I.

[0009] Furthermore, a regulating valve II and a flow meter I are provided on the main pipe between the pipeline III and the distillation tower, and the controller is respectively connected to the flow meter I and the regulating valve II.

[0010] Furthermore, the pump I is a shielded pump with a head of 110m.

[0011] Furthermore, the pump II is a shielded pump with a head of 105m.

[0012] Further, a stirring mechanism is provided in the transfer tank.

[0013] Further, a valve III is provided on the main pipe.

[0014] Further, the recovery storage tank is connected to the analytical column through pipeline IV. A heat exchanger is connected to pipeline IV. A temperature sensor is also provided on the recovery storage tank. A regulating valve IV is provided on the medium inlet pipe of the heat exchanger. The controller is respectively connected to the temperature sensor and the regulating valve IV for control connection.

[0015] Advantages of the present utility model:

[0016] 1. In the present utility model, the chlorosilane recovered from the recovery section is subjected to primary heat exchange through a heat exchanger and then temporarily stored in the recovery storage tank. At this time, the temperature of the material flow is about 60°C. Then, the chlorosilane material in the recovery storage tank is divided into two material flows: a main conveying path and an adjusting auxiliary path. The main conveying path is as follows: the chlorosilane material in the recovery storage tank is pressurized to 17 bar by pump I through pipeline I, and then sent to the distillation column through the main pipe. The liquid level gauge on the recovery storage tank is connected to the regulating valve I on pipeline II for control connection to ensure the stability of the material flow in the main pipe; the adjusting auxiliary path is used to temporarily store excess chlorosilane material or supplement the material that is less than the preset value, and assist in ensuring the stability of the material flow in the main pipe. It is no longer necessary to pump it to the original tank area for temporary storage after water cooling, and then send a stable material flow to the distillation section after the material is stable. In this way, both the stable operation of the distillation column can be ensured, and excessive impurities introduced by excessive conveying processes (too many conveying pipelines) can be avoided. At the same time, the pump II on the adjusting auxiliary path can select a smaller power canned motor pump. The reduction of the conveying volume in the auxiliary path also reduces the power consumption and the operating cost, thus reducing the power consumption of pump I and pump II.

[0017] 2. In the present utility model, the recovery storage tank is connected to the analytical column through pipeline IV. A heat exchanger is connected to pipeline IV. A temperature sensor is also provided on the recovery storage tank. A regulating valve IV is provided on the medium inlet pipe of the heat exchanger. The controller is respectively connected to the temperature sensor and the regulating valve IV for control connection. Through the interlock of the temperature sensor and the regulating valve IV, precise control of the material temperature in the recovery storage tank is achieved, and it is maintained at about 60°C, which is also the optimal maintenance temperature during the operation of the distillation column. When the material flow in the recovery storage tank is directly sent to the distillation column, the normal operation of the distillation column and even the stable operation of the entire conveying system are prevented from being affected by temperature fluctuations.

[0018] 3. In the present utility model, since only a part of the material flow passes through pipeline II, a pump with a smaller power can be selected. In this solution, pump I preferably selects a canned motor pump with a head of 110 m, and pump II preferably selects a canned motor pump with a head of 105 m. Compared with the traditional technology, the energy consumption can be reduced.

[0019] 4. In the present utility model, the valve III provided on the main pipe preferably selects a check valve to ensure the conveying of the material flow in the expected direction. Description of the Drawings

[0020] Figure 1 It is a structural schematic diagram of the utility model.

[0021] Figure 2 is a structural diagram of another embodiment of a conveying system.

[0022] Figure 3 It is a structural diagram of another embodiment of the conveying system

[0023] Among them, 1. Recovery storage tank; 2. Transfer tank; 3. Distillation tower; 4. Pipeline I; 5. Pump I; 6. Main pipe; 7. Pipeline II; 8. Control valve I; 9. Pump II; 10. Pipeline III; 11. Liquid level sensor; 12. Control valve II; 13. Flow meter I; 14. Analysis tower; 15. Heat exchanger; 16. Valve III; 17. Pipeline IV; 18. Control valve IV; 19. Controller; 20. Temperature sensor; 2.1. Material outlet; 2.2. Stirring mechanism; 3.1. Feed inlet; 15.1. Medium inlet pipe. DETAILED DESCRIPTION

[0024] The present invention is further described in detail below in conjunction with the embodiments, but the implementation manner of the present invention is not limited thereto.

[0025] Example 1

[0026] A conveying system for recovering chlorosilane materials and directly supplying them to a distillation section, belonging to the technical field of polysilicon production equipment, comprises a recovery storage tank 1, a transfer tank 2, a distillation tower 3 and a controller 19, with reference to Figure 1 The recovery tank 1 is connected to the pump I5 through the pipeline I4, and the pump I5 is directly connected to the feed port 3.1 of the distillation tower 3 through the main pipe 6. The pump I5 is connected to the transfer tank 2 through the pipeline II7, and the pipeline II7 is provided with a regulating valve I8. The material outlet 2.1 of the transfer tank 2 is connected to the pump II9 and then merged into the main pipe 6 through the pipeline III10. The recovery tank 1 is provided with a liquid level sensor 11, and the controller 19 is respectively controlled and connected with the liquid level sensor 11 and the regulating valve I8.

[0027] Preferably, the pump Ⅰ5 is a shielded pump with a head of 110m.

[0028] Preferably, the pump II 9 is a canned pump with a head of 105 m.

[0029] During transportation by the conveying system, when the liquid level sensor 11 detects that the liquid level of the recovery tank 1 is equal to the preset value, the regulating valve I8 is closed, and the material in the recovery tank 1 is directly transported to the distillation tower 3 via the pipeline I4 and the main pipe 6;

[0030] When the liquid level sensor 11 detects that the liquid level in the recovery storage tank 1 is higher than the preset value, the regulating valve I 8 is opened, and a part of the logistics is separated and temporarily stored in the transfer tank 2 to ensure that the logistics directly transported from the main pipe 6 to the distillation column 3 is a constant value;

[0031] When the liquid level sensor 11 detects that the liquid level in the recovery storage tank 1 is lower than the preset value, the regulating valve I 8 is closed, and the pump II 9 is started to supply a part of the logistics from the transfer tank 2 to the main pipe 6 to ensure that the logistics directly transported from the main pipe 6 to the distillation column 3 is a constant value. This can not only ensure the stable operation of the distillation column 3, but also avoid introducing too many impurities in the excessive transportation process (too many transportation pipelines). At the same time, the reduction of the auxiliary pipeline transportation volume also reduces the power consumption.

[0032] Example 2

[0033] This example is a further optimization based on Example 1. The difference is that a regulating valve II 12 and a flowmeter I 13 are provided on the main pipe 6 between the pipeline III 10 and the distillation column 3, and the controller 19 is respectively connected to the flowmeter I 13 and the regulating valve II 12 for control. Refer to Figure 2 .

[0034] Preferably, a stirring mechanism 2.2 is provided in the transfer tank 2 to stir the logistics in the transfer tank 2 to prevent the logistics from aggregating into groups and affecting the normal transportation.

[0035] Example 3

[0036] This example is a further optimization based on Example 2. The difference is that a valve III 16 is provided on the main pipe 6, and the valve III 16 is preferably a one-way valve. Refer to Figure 3 .

[0037] Example 4

[0038] Compared with Examples 1-3, the difference in this example is that the recovery storage tank 1 is connected to the analytical column 14 through a pipeline IV 17. Refer to Figure 3 , a heat exchanger 15 is connected to the pipeline IV 17, a temperature sensor is also provided on the recovery storage tank 1, a regulating valve IV 18 is provided on the medium inlet pipe 15.1 of the heat exchanger 15, and the controller 19 is respectively connected to the temperature sensor and the regulating valve IV 18 for control.

[0039] Example 5

[0040] This example takes a relatively excellent conveying system for directly supplying the recovered chlorosilane material to the rectification section of our company as an example to further illustrate this solution.

[0041] Refer to Figure 3The conveying system includes a recovery tank 1, a transfer tank 2, a distillation tower 3 and a controller 19. The recovery tank 1 is used to collect the chlorosilane material sent from the analysis tower 14 in the recovery section of polysilicon production. The temperature of the chlorosilane material sent from the analysis tower 14 is generally 80°C. After the first-level heat exchange in the heat exchanger 15, the temperature of the chlorosilane material drops to 60°C and can be directly sent to the distillation tower 3 of the distillation section for treatment.

[0042] The main reason why the chlorosilane material sent out from the analysis tower 14 is generally not directly transported to the distillation tower 3 in the prior art is that the amount of recovered material is fluctuating and very unstable. If all of it is directly sent to the distillation tower 3, the fluctuation of the feed amount of the distillation tower 3 will disrupt the normal operation of the distillation tower 3, and the pressure and temperature of the whole tower will fluctuate frequently, affecting the distillation effect.

[0043] In this embodiment, the recovery tank 1 is connected to the pump I5 through the pipeline I4, and the pump I5 is directly connected to the feed port 3.1 of the distillation tower 3 through the main pipe 6. The pump I5 is connected to the transfer tank 2 through the pipeline II7, and the pipeline II7 is provided with a regulating valve I8. The material outlet 2.1 of the transfer tank 2 is connected to the pump II9 and then merged into the main pipe 6 through the pipeline III10. The recovery tank 1 is provided with a liquid level sensor 11, and the controller 19 is respectively connected to the liquid level sensor 11 and the regulating valve I8. The liquid level sensor 11 and the regulating valve I8 are interlocked to control the material flow entering the main pipe 6 to be stable. The main pipe 6 between the pipeline III10 and the distillation tower 3 is provided with a regulating valve II12 and a flowmeter I13, and the controller 19 is respectively connected to the flowmeter I13 and the regulating valve II12. The flowmeter I13 uploads the collected flow signal to the controller 19, and the controller 19 controls the opening and closing of the regulating valve II12.

[0044] In this embodiment, the pump I5 is a shielded pump with a head of 110 m; the pump II9 is ​​a shielded pump with a head of 105 m.

[0045] In this embodiment, a stirring mechanism 2.2 is provided in the transfer tank 2.

[0046] In this embodiment, a valve III16 is provided on the main pipe 6, and the valve III16 is preferably a one-way valve.

[0047] In this embodiment, the recovery tank 1 is connected to the analytical tower 14 via a pipeline IV17, a heat exchanger 15 is connected to the pipeline IV17, a temperature sensor is also provided on the recovery tank 1, a regulating valve IV18 is provided on the medium inlet pipe 15.1 of the heat exchanger 15, and a controller 19 is respectively connected to the temperature sensor and the regulating valve IV18 for control. The temperature sensor and the regulating valve IV18 are interlocked to control the temperature of the material in the recovery tank 1 to be stable within the expected range.

[0048] The chlorosilane material in the recovery storage tank 1 is divided into two streams: the main conveying path and the auxiliary regulating path. The main conveying path is as follows: The chlorosilane material in the recovery storage tank 1 is pressurized to 17 bar by the pump I 5 through the pipeline I 4, and then sent to the distillation column 3 through the main pipe 6. The control valve I 8, the control valve II 12, and the valve III 16 on the main pipe 6 are all normally open valves. The flowmeter I 13 is used to collect the flow rate on the main pipe 6 entering the distillation column 3 and upload the collected information to the controller 19. The auxiliary controller 19 judges the conveying process and issues instructions to the corresponding actuators (such as the control valve I 8, the pump II 9, etc.) to ensure the stability of the material quantity conveyed to the distillation column 3. The auxiliary regulating path includes the pipeline II 7, the transfer tank 2, and the pump II 9. The control valve I 8 installed on the pipeline II 7 is interlocked with the liquid level sensor 11 of the recovery storage tank 1. The conveying volume is assisted to be regulated by adjusting the opening degree of the control valve I 8 or starting and stopping the pump II 9. The transfer tank 2 in the auxiliary regulating path is used to temporarily store the excess chlorosilane material or supply the material that is less than the preset value, which helps to ensure the stability of the material flow in the main pipe 6. It is no longer necessary to pump it to the original tank area for temporary storage after water cooling and then convey stable material flow to the distillation section after the material is stable. This can not only ensure the stable operation of the distillation column 3, but also avoid introducing too many impurities due to excessive conveying processes (too many conveying pipelines). At the same time, the reduction of the conveying volume in the auxiliary path also reduces the power consumption.

[0049] In the original system, the material transfer pumps in the recovery section and the tank area are all large-flow pumps. Calculated based on processing 1,215,000 m 3 of chlorosilane material per month, after adopting this system, 90,720 kW•h of electricity can be saved per month compared with the previous process, and the operating cost can be reduced by about 48,000 yuan per month.

Claims

1. A conveying system for directly supplying recovered chlorosilane materials to a rectification section, characterized in that: The invention comprises a recovery tank (1), a transfer tank (2), a distillation tower (3) and a controller (19). The recovery tank (1) is connected to a pump I (5) via a pipeline I (4). The pump I (5) is directly connected to a feed port (3.1) of a distillation tower (3) via a main pipe (6). The pump I (5) is connected to the transfer tank (2) via a pipeline II (7). A regulating valve I (8) is provided on the pipeline II (7). The material outlet (2.1) of the transfer tank (2) is connected to the pump II (9) and then flows into the main pipe (6) via a pipeline III (10). A liquid level sensor (11) is provided on the recovery tank (1). The controller (19) is respectively connected to the liquid level sensor (11) and the regulating valve I (8).

2. The conveying system for directly supplying the rectification section with recovered chlorosilane materials according to claim 1, wherein: A regulating valve II (12) and a flow meter I (13) are provided on the main pipe (6) between the pipeline III (10) and the distillation tower (3), and a controller (19) is respectively connected to the flow meter I (13) and the regulating valve II (12) for control.

3. The conveying system for directly supplying the rectification section with recycled chlorosilane materials according to claim 1, wherein: The pump I (5) is a canned pump with a head of 110 m.

4. The conveying system for directly supplying the rectification section with recovered chlorosilane materials according to claim 1, characterized in that: The pump II (9) is a canned pump with a head of 105 m.

5. The conveying system for directly supplying the rectification section with recovered chlorosilane materials according to claim 1, characterized in that: The transfer tank (2) is provided with a stirring mechanism (2.2).

6. The conveying system for directly supplying the recovered chlorosilane material to the rectification section according to claim 1, wherein: The main pipe (6) is provided with a valve III (16).

7. The conveying system for directly supplying the recovered chlorosilane material to the rectification section according to claim 1, wherein: The recovery tank (1) is connected to the analytical tower (14) via a pipeline IV (17), the pipeline IV (17) is connected to a heat exchanger (15), the recovery tank (1) is also provided with a temperature sensor, a regulating valve IV (18) is provided on a medium inlet pipe (15.1) of the heat exchanger (15), and a controller (19) is respectively connected to the temperature sensor and the regulating valve IV (18).

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