Testing device for on-line complexing agent adding of rectifying tower

Abstract

The utility model relates to the technical field of polycrystalline silicon production equipment, in particular to a testing device for online adding a complexing agent into a rectifying tower. A liquid level meter is arranged on the feeding tank; a gas phase communication opening is formed in the feeding tank; the gas phase communicating port is communicated with a charged device through a communicating pipe; a gas phase communicating valve is arranged on the communicating pipe; a pressure gauge is arranged on the communicating pipe; a feeding replacement opening is formed in the feeding tank; a feeding replacement valve is arranged on the feeding replacement port; a liquid outlet is formed in the bottom of the feeding tank; the liquid outlet is connected with a reserved opening of a fed device through a liquid outlet pipe; a flow meter is arranged on the liquid discharge pipe; a liquid discharging valve is arranged on the liquid discharging pipe; the lower liquid valve is arranged at the downstream of the flow meter; a liquid discharge pipe is connected to the liquid discharge pipe; the liquid discharging pipe is connected between the flow meter and the liquid discharging valve; and a liquid discharge guide shower is arranged on the liquid discharge pipe. By adopting the device, the complexing agent can be added into the running rectifying tower, the test efficiency is high, the running of the rectifying tower is not influenced, and the cost is low.

Description

Technical Field

[0001] The utility model relates to the technical field of polysilicon production equipment, in particular to a test device for adding a complexing agent online to a distillation tower. Background Art

[0002] The raw materials for polysilicon production are mostly prepared by cold hydrogenation synthesis to prepare trichlorosilane. In the process of cold hydrogenation to produce trichlorosilane, impurities such as BCl3, PCl3, PCl5, POCl3, and methylchlorosilane will be formed. At present, the impurity removal process of chlorosilane generally undergoes multi-stage distillation to repeatedly remove impurities, but only through distillation can only remove substances with a large difference in segregation coefficient with trichlorosilane. Another part of impurities with very close segregation coefficients will form azeotropes with chlorosilane. The boiling points of each component are relatively close, and it is difficult to separate the components by commonly used separation methods. Among them, non-metallic impurities B and non-metallic impurities P are more difficult to remove. At present, complex adsorption is widely used for impurity removal. The impurity remover used is generally based on macroporous resin loaded with organic amines. Impurities are removed through adsorption devices, and boron and phosphorus impurities are removed by chemical adsorption principle. However, due to a series of chemical reactions that occur during the adsorption process, which are almost irreversible, the adsorbent needs to be frequently replaced, and the adsorption efficiency is greatly reduced in the later period of use. Although the content of B and P in the chlorosilane after adsorption is greatly reduced, the impurity content cannot be continuously guaranteed to meet the requirements for the preparation of electronic first-level polysilicon. In order to continuously improve the quality of polysilicon products, it is necessary to continue to effectively reduce the content of impurities such as B and P in trichlorosilane. In order to verify the effect of various new complexing agents on removing impurities, as well as the effect of the same complexing agents from different manufacturers, it is necessary to continuously try to add various complexing agents during the distillation of trichlorosilane in order to find an adsorbent with better effect. At present, when adding complexing agents to the distillation tower, it is necessary to add them when the distillation tower is stopped, which affects the operation of the entire production line, increases the test cost, and has low test efficiency. Utility Model Content

[0003] In view of this, the utility model provides a test device for online addition of complexing agent to a distillation tower, the main purpose of which is to realize the addition of complexing agent to a running distillation tower, with high test efficiency, no influence on the operation of the distillation tower and low test cost.

[0004] In order to achieve the above purpose, the utility model mainly provides the following technical solutions:

[0005] The embodiment of the utility model provides a test device for adding a complexing agent online to a distillation tower, comprising: a feeding tank;

[0006] The main body of the feeding tank is a cylindrical container; the bottom of the main body is conical;

[0007] The feeding tank is provided with a liquid level gauge;

[0008] The feeding tank is provided with a gas phase communication port; the gas phase communication port is connected with the feeding device through a connecting pipe;

[0009] The connecting pipe is provided with a gas phase connecting valve for controlling the opening and closing of the connecting pipe;

[0010] The connecting pipe is provided with a pressure gauge;

[0011] The feeding tank is provided with a feeding replacement port; the feeding replacement port is provided with a feeding replacement valve;

[0012] The bottom of the feeding tank is provided with a liquid discharge port; the liquid discharge port is connected to the reserved port of the feeding device through a down pipe;

[0013] A flow meter is provided on the lower liquid pipe;

[0014] The lower liquid pipe is provided with a lower liquid valve; the lower liquid valve is provided downstream of the flow meter;

[0015] The lower liquid pipe is connected with a drain pipe; the drain pipe is connected between the flow meter and the lower liquid valve;

[0016] The drainage pipe is provided with a drainage guide.

[0017] Furthermore, the liquid level gauge is a magnetic flap liquid level gauge.

[0018] Furthermore, the feed replacement port is communicated with an exhaust gas treatment system.

[0019] Furthermore, the position of the downpipe is lower than the bottom of the feeding tank.

[0020] Furthermore, the position of the liquid discharge pipe is lower than that of the liquid down pipe.

[0021] By means of the above technical solution, the test device for adding complexing agent online to a distillation tower of the utility model has at least the following advantages:

[0022] The complexing agent can be added to the running distillation tower, the test efficiency is high, the operation of the distillation tower is not affected, and the test cost is low.

[0023] The above description is only an overview of the technical solution of the utility model. In order to more clearly understand the technical means of the utility model and implement it according to the contents of the specification, the following is a detailed description of the preferred embodiments of the utility model in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 A schematic diagram of a test device for adding a complexing agent online to a distillation tower provided in an embodiment of the utility model;

[0025] Figure 2 A schematic diagram of a test device for online addition of a complexing agent to a distillation tower provided in an embodiment of the utility model and connected to the distillation tower.

[0026] As shown in the figure: 1 is the gas phase connecting valve, 2 is the feeding replacement valve, 3 is the liquid level meter, 4 is the drainage guide, 5 is the flow meter, 6 is the lower liquid valve, 7 is the feeding tank, 8 is the pressure gauge, and 9 is the distillation tower. DETAILED DESCRIPTION

[0027] In order to further explain the technical means and effects adopted by the utility model to achieve the predetermined utility model purpose, the specific implementation methods, structures, features and effects of the utility model application are described in detail below in conjunction with the accompanying drawings and preferred embodiments. In the following description, different "one embodiment" or "embodiment" does not necessarily refer to the same embodiment. In addition, specific features, structures, or characteristics in one or more embodiments may be combined in any suitable form.

[0028] like Figure 1 and Figure 2 As shown, an embodiment of the utility model proposes a test device for online addition of complexing agent to a distillation tower, comprising: a feeding tank 7; the main body of the feeding tank 7 is a cylindrical container; the bottom of the main body is conical; a liquid level gauge 3 is provided on the feeding tank 7 for observing and monitoring the liquid level of the feeding tank 7; preferably, in this embodiment, the liquid level gauge 3 is a magnetic flap liquid level gauge 3. The feeding tank 7 has a gas-phase connecting port; the gas-phase connecting port is connected to the fed device through a connecting pipe to achieve the consistency of the air pressure in the feeding tank 7 with the air pressure in the fed device; a gas-phase connecting valve 1 is provided on the connecting pipe to control the opening and closing of the connecting pipe. A pressure gauge 8 is provided on the connecting pipe to monitor the pressure of the feeding tank 7.

[0029] The feeding tank 7 is provided with a feeding replacement port; the feeding replacement port is provided with a feeding replacement valve 2; the feeding replacement port is connected to the feeding container or the exhaust gas treatment system; the feeding replacement port is connected to the exhaust gas treatment system to treat the replaced exhaust gas. The feeding replacement valve 2 can control the feeding replacement port to be connected to the feeding container or the exhaust gas treatment system. The feeding replacement valve 2 is a two-position three-way valve, and can also be controlled by two independent valves.

[0030] A drain port is provided at the bottom of the feeding tank 7; the drain port is connected to the reserved port of the feeding device through a lower liquid pipe; in this embodiment, the position of the lower liquid pipe is lower than the bottom of the feeding tank 7 so that the complexing agent can be emptied by gravity. A flow meter 5 is provided on the lower liquid pipe to check the feeding rate; a lower liquid valve 6 is provided on the lower liquid pipe; the lower liquid valve 6 is provided downstream of the flow meter 5; a drain pipe is connected to the lower liquid pipe; the drain pipe is connected between the flow meter 5 and the lower liquid valve 6; in this embodiment, the position of the drain pipe is lower than that of the lower liquid pipe so that the materials in the feeding tank 7 and the lower liquid pipe can be emptied by gravity. A drain guide 4 is provided on the drain pipe to control the on and off of the drain pipe.

[0031] An embodiment of the utility model proposes a test device for adding a complexing agent to a distillation tower online, which can realize the addition of a complexing agent to a running distillation tower 9, has high test efficiency, does not affect the operation of the distillation tower 9, has low cost, can quickly verify the effect of a new complexing agent in removing impurities, and is convenient for finding an efficient complexing agent for removing impurities, thereby improving the quality of trichlorosilane in polysilicon production.

[0032] An embodiment of the utility model provides a test device for online addition of a complexing agent to a distillation tower. The device has a simple structure, is light and compact, does not require additional large-scale supporting equipment, and is easy to install and use at any time. The device is not only suitable for the distillation tower 9, but can also be installed in various reaction vessels, storage tanks, etc. for small-scale experiments.

[0033] An embodiment of the utility model provides a test device for online addition of a complexing agent to a distillation tower. During the feeding process, a connecting pipe is used to balance the pressure inside a feeding tank 7 and a device to be fed. The liquid gravity potential energy is used for gravity feeding, and there is no need to pressurize the system to avoid introducing impurities.

[0034] The lower liquid pipe is connected to the reserved port of the distillation tower 9, the lower liquid valve 6 is in a closed state, the feeding replacement valve 2 is opened, and the complexing agent to be added to the feeding tank 7 is added by a funnel. After the filling is completed, the feeding replacement valve 2 is closed; the gas phase connecting valve 1 is opened, and the gas phase inside the fed device is used to replace the feeding tank 7, and the replacement gas is discharged to the ground trough / tail gas treatment system through the feeding replacement valve 2. After the replacement is qualified, the feeding replacement valve 2 is closed. At this time, since the gas phase connecting valve 1 is in an open state, the pressure inside the feeding tank 7 and the fed device gradually tends to be consistent. By opening the lower liquid valve 6, the complexing agent in the feeding tank 7 will flow into the fed device by itself under the action of gravitational potential energy to achieve the purpose of feeding. During the feeding process, the liquid level of the feeding tank 7 can be checked through the liquid level meter 3, the pressure of the feeding tank 7 can be checked through the pressure gauge 8, the feeding rate can be checked through the flow meter 5, and the liquid lowering valve 6 can control the liquid lowering speed. The feeding tank 7 is a cylindrical container, which is convenient for calculating the volume of the feeding tank 7 according to the diameter of the cylinder. The bottom is conical in design to facilitate complete drainage of the liquid. After the feeding is completed, the liquid lowering valve 6 is closed, and the feeding tank 7 is replaced through the drainage guide 4 to facilitate the feeding of the next test.

[0035] In the description of the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0036] The standard parts used in the utility model can all be purchased from the market, and special-shaped parts can be customized according to the instructions and the drawings. The specific connection methods of each part adopt the conventional means such as mature bolts, rivets, welding, etc. in the existing technology. The machinery, parts and equipment all adopt the conventional models in the existing technology, and the circuit connection adopts the conventional connection method in the existing technology, which will not be described in detail here.

[0037] The above is only a preferred embodiment of the present invention and does not constitute any form of limitation to the present invention. Any simple modification, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A test device for adding a complexing agent online to a distillation tower, characterized in that: Including: feeding tank; The main body of the feeding tank is a cylindrical container; the bottom of the main body is conical; The feeding tank is provided with a liquid level gauge; The feeding tank is provided with a gas phase communication port; the gas phase communication port is connected with the feeding device through a connecting pipe; The connecting pipe is provided with a gas phase connecting valve for controlling the opening and closing of the connecting pipe; The connecting pipe is provided with a pressure gauge; The feeding tank is provided with a feeding replacement port; the feeding replacement port is provided with a feeding replacement valve; The bottom of the feeding tank is provided with a liquid discharge port; the liquid discharge port is connected to the reserved port of the feeding device through a down pipe; A flow meter is provided on the lower liquid pipe; The lower liquid pipe is provided with a lower liquid valve; the lower liquid valve is provided downstream of the flow meter; The lower liquid pipe is connected with a drain pipe; the drain pipe is connected between the flow meter and the lower liquid valve; The drainage pipe is provided with a drainage guide.

2. The test device for adding a complexing agent online to a distillation tower according to claim 1, characterized in that: The liquid level meter is a magnetic flap liquid level meter.

3. The test device for adding a complexing agent online to a distillation tower according to claim 1, characterized in that: The feed replacement port is communicated with the tail gas treatment system.

4. The test device for adding a complexing agent online to a distillation tower according to claim 1, characterized in that: The position of the downpipe is lower than the bottom of the feeding tank.

5. The test device for adding a complexing agent online to a distillation tower according to claim 4, characterized in that: The position of the liquid discharge pipe is lower than that of the liquid down pipe.

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