Bed sampling device

Abstract

The present invention discloses a bed sampling device, comprising an internal sampling tube and an external sampler; wherein the internal sampling tube extends into the bed, passes through the bottom of the reactor and is connected to the external sampler; the external sampler is an oblique three-way structure, and is provided with a nitrogen exhaust port and an air inlet. This embodiment can solve the problem that the downstream sampling of the existing fluidized bed reactor cannot accurately reflect the real-time particle size distribution inside the reactor, and the secondary sampling brings more impurity pollution.

Description

Technical Field

[0001] The invention relates to the technical field of automated production, and in particular to a bed sampling device. Background Art

[0002] The technology of producing granular silicon by silane fluidized bed has great advantages in all aspects. Fluidized bed reactor provides high and large production volume with less energy consumption, and its product is granular silicon, which can be packaged and sold without processing, greatly reducing production costs. Fluidized bed reactor can be continuous and highly automated, and the product specifications can not only reach solar grade, but also electronic grade, which can connect with the advantages of downstream industries.

[0003] In the process of implementing the present invention, the inventors found that there are at least the following problems in the prior art:

[0004] Generally, the particle size sample or mass sample is obtained at the downstream position of the fluidized bed reactor. Due to the hysteresis, it is impossible to accurately reflect the real-time particle size distribution inside the reactor, and it is impossible to establish an effective correlation between it and the relevant process parameters. In addition, the current single bed sampling device used for research properties needs to remove the remaining materials in the pipeline before, and perform two samplings to remove the empty sample, which will bring more pollution and reduce the sampling efficiency, thereby increasing labor costs. Summary of the invention

[0005] In view of this, an embodiment of the present invention provides a bed sampling device, which can solve the problem that the downstream sampling of the existing fluidized bed reactor cannot accurately reflect the real-time particle size distribution inside it, and the secondary sampling brings more impurity pollution.

[0006] To achieve the above-mentioned purpose, a bed sampling device is provided according to an embodiment of the present invention, comprising an internal sampling tube and an external sampler; wherein the internal sampling tube extends into the interior of the bed and passes through the bottom of the reactor to be connected with the external sampler; the external sampler is an oblique three-way structure, and is provided with an exhaust port and an air inlet for nitrogen.

[0007] Optionally include:

[0008] A nitrogen inlet is provided at one end of the straight pipe section of the external sampler oblique three-way structure and the oblique pipe section respectively, and a nitrogen outlet is provided at the other end of the straight pipe section of the external sampler oblique three-way structure.

[0009] Optionally include:

[0010] The top end of the straight pipe section of the external sampler's oblique tee structure is connected to the internal sampling tube, the upper end of the straight pipe section of the external sampler's oblique tee structure is provided with a nitrogen outlet, and the lower end of the straight pipe section and the oblique pipe section of the external sampler's oblique tee structure are respectively provided with nitrogen inlets.

[0011] Optionally, include

[0012] The volume from the bifurcation of the oblique tee structure of the external sampler to the bottom end of the straight pipe section is greater than the volume of the internal sampling tube.

[0013] Optionally include:

[0014] The inner and outer diameter surfaces of the internal sampling tube have a protective coating or a protective sleeve, and the inner diameter surface of the external sampler has a protective coating.

[0015] Optionally include:

[0016] A protective coating is provided partially or entirely on the outer diameter surface of the inner sampling tube.

[0017] Optionally include:

[0018] The inner diameter surface of the internal sampling tube is provided with protective sleeves in sections or continuously, and the protective sleeves are closely fitted to the inner wall of the internal sampling tube.

[0019] Optionally include:

[0020] Two layers of flange surfaces are arranged on the outer wall of the internal sampling tube, the upper flange surface is connected to the reactor, and the lower flange surface is connected to the external sampler.

[0021] Optionally include:

[0022] Each port of the external sampler in an oblique three-way structure is equipped with a ball valve.

[0023] Optionally include:

[0024] A plurality of thermometers are respectively distributed at different heights of the inclined pipe section of the inclined tee structure of the external sampler.

[0025] One embodiment of the above invention has the following advantages or beneficial effects: The bed sampling device of the present invention can obtain samples inside the reactor, timely analyze the real-time particle size distribution and quality status inside the reactor, and provide reliable data for the adjustment of the reactor. The inner and outer diameter surfaces of the internal sampler are both designed with protective coatings or protective sleeves, and the protective coating design of the inner diameter surface of the external sampler ensures that the product and the sample itself are not contaminated during the sampling process. In addition, the oblique three-way structure of the external sampler avoids the tediousness of multiple operations, improves the sampling efficiency, and can avoid unnecessary impurity contamination.

[0026] The further effects of the above-mentioned non-conventional optional manner will be described below in conjunction with the specific implementation manner. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The accompanying drawings are used to better understand the present invention and do not constitute an improper limitation of the present invention.

[0028] Figure 1 is a schematic diagram of the longitudinal section structure of an internal sampling tube of a bed sampling device according to an embodiment of the present invention;

[0029] Figure 2 Schematic diagram of the structure of an external sampler of a bed sampling device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0030] The following is a description of exemplary embodiments of the present invention in conjunction with the accompanying drawings, including various details of the embodiments of the present invention to facilitate understanding, which should be considered as merely exemplary. Therefore, it should be recognized by those of ordinary skill in the art that various changes and modifications may be made to the embodiments described herein without departing from the scope and spirit of the present invention. Similarly, for clarity and conciseness, the description of well-known functions and structures is omitted in the following description.

[0031] At least one embodiment of the present invention provides a bed sampling device, which includes an internal sampling tube and an external sampler. The internal sampling tube extends into the bed and passes through the bottom of the reactor to connect with the external sampler. The external sampler is an oblique three-way structure, and is provided with an exhaust port and an air inlet for nitrogen.

[0032] It can be seen that a bed sampling device is adopted inside the reactor, that is, the internal sampling tube can extend into the bed to a certain height, directly obtain the sample inside the reactor, and at the same time, the appropriate height will not cause the reactants to agglomerate in the sampling device, resulting in affecting the normal operation of the normal reactor. Preferably, the height at which the internal sampling tube extends into the inside of the bed is 10-50cm. The design of the oblique three-way structure of the external sampler can discharge the material previously remaining in the internal sampling tube into the straight pipe section of the oblique three-way structure of the external sampler during the sampling process as a clearing sample, and then the sample obtained by the oblique pipe section is used as a normal sample. Therefore, the present invention can obtain a normal sample through a single operation, avoiding the tediousness of multiple operations and improving the sampling efficiency. That is, the present invention realizes the ability to obtain real-time particle size samples of the bed in the reactor, accurately reflecting the real-time particle size distribution inside the reactor.

[0033] Some other embodiments of the present invention provide bed sampling devices, in which nitrogen inlets are respectively provided at one end of the straight pipe section and the inclined pipe section of the external sampler's inclined three-way structure, and a nitrogen outlet is provided at the other end of the straight pipe section of the external sampler's inclined three-way structure.

[0034] Furthermore, the top of the straight tube section of the oblique three-way structure of the external sampler is connected to the internal sampling tube, the upper end of the straight tube section of the oblique three-way structure of the external sampler is provided with a nitrogen outlet, and the lower end of the straight tube section of the oblique three-way structure of the external sampler and the oblique tube section are respectively provided with nitrogen inlets. Thus, during the sampling process, the material previously remaining in the internal sampling tube can be discharged to the lower end of the straight tube section of the oblique three-way structure of the external sampler as a clear sample, and then the sample obtained by the oblique tube section is used as a normal sample. Among them, the clear sample is the material that previously remained in the internal sampling tube, which cannot reflect the current material in the reactor and needs to be discharged. The "normal sample" taken out after the clear sample is discharged is the material in the reactor obtained at that time, which is a real-time sample.

[0035] It is worth noting that the volume from the bifurcation of the external sampler oblique tee structure to the bottom of the straight pipe section is greater than the volume of the internal sampling tube. In addition, the shape of the straight pipe section is a cylinder, but is not limited to a regular cylinder.

[0036] Preferably, each port of the external sampler in an oblique three-way structure is equipped with a ball valve. In addition, two layers of flange surfaces are arranged on the outer wall of the internal sampling tube, the upper flange surface is connected to the reactor, and the lower flange surface is connected to the external sampler.

[0037] Some further embodiments of the present invention provide a bed sampling device, wherein the inner and outer diameter surfaces of the internal sampling tube have a protective coating or a protective sleeve, which can reduce or eliminate the contamination of granular polysilicon caused by contact with the surface of the metal insert in the reactor. The inner diameter surface of the external sampler has a protective coating, which can reduce or eliminate the contamination of the granular polysilicon sample caused by contact with the wall surface of the external sampler. Therefore, the present invention can solve the problem of the deficiency of more impurity contamination caused by secondary sampling, thereby avoiding unnecessary impurity contamination. It is worth noting that the thickness of the protective coating is preferably in the range of 0.2 mm to 0.9 mm.

[0038] Preferably, if a protective coating is provided on the outer diameter surface of the inner sampling tube, the protective coating may be provided partially or entirely, wherein the protective coating comprises quartz, silicon, low nickel alloy, nickel alloy, cobalt alloy, silicon nitride, graphite, silicon carbide, molybdenum, or molybdenum alloy.

[0039] If a protective coating is provided on the inner diameter surface of the inner sampling tube, the protective coating comprises quartz, silicon, a low nickel alloy, a nickel alloy, a cobalt alloy, silicon nitride, graphite, silicon carbide, molybdenum, or a molybdenum alloy.

[0040] If a protective sleeve is provided on the inner diameter surface of the internal sampling tube, the protective sleeve can be provided in sections or continuously, and the protective sleeve is closely fitted to the inner wall of the internal sampling tube. The material of the protective sleeve includes quartz, silicon, silicon nitride, graphite or silicon carbide.

[0041] If the outer sampler inner diameter surface has a protective coating, the protective coating includes quartz, silicon, a low nickel alloy, a nickel alloy, a cobalt alloy, silicon nitride, graphite, silicon carbide, molybdenum, or a molybdenum alloy.

[0042] It is also worth noting that the material of the internal sampling tube is preferably an alloy containing more than 18% chromium and more than 8% nickel, wherein the alloy includes 304 series stainless steel, low nickel alloy, nickel alloy, Incoloy alloy, cobalt alloy, ULTIMET alloy or molybdenum alloy.

[0043] Of course, the material or coating material of the bed sampling device can be modified according to different actual application scenarios, so as to more effectively solve the pollution problem.

[0044] The bed sampling device provided in some other embodiments of the present invention may also include a thermometer. A plurality of thermometers are respectively distributed at different heights of the inclined pipe section of the inclined tee structure of the external sampler. Preferably, the installation form of the thermometer may include an inserted thermocouple thermometer or a surface thermocouple thermometer.

[0045] As a specific embodiment of the present invention, Figure 1 and 2 As shown, the bed sampling device includes an internal sampling tube 1 and an external sampler, the inner diameter surface of the internal sampling tube 1 has a protective coating or a protective sleeve 3, and the outer diameter surface of the internal sampling tube 1 has a protective coating 2. The height of the internal sampling tube 1 is required to extend into the fluidized bed and be in a moderate position, and pass through the bottom of the reactor to connect with the top of the external sampler. The inner diameter surface of the external sampler has a protective coating 4, and the external sampler is an oblique three-way structure. The upper end of the straight pipe section 5 of the oblique three-way structure of the external sampler is provided with a nitrogen outlet 9, the lower end of the straight pipe section 5 of the oblique three-way structure of the external sampler is provided with a first nitrogen inlet 7, and the oblique pipe section 6 of the oblique three-way structure of the external sampler is provided with a second nitrogen inlet 8. A plurality of thermometers 10 are respectively distributed at different heights of the oblique pipe section 6 of the oblique three-way structure of the external sampler.

[0046] The fluidized bed reactor is a reaction device, and the fluidized bed layer refers to the height formed by the materials in the fluidized bed reactor.

[0047] Better, such as Figure 1 As shown in , two layers of flange surfaces are arranged on the outer wall of the internal sampling tube 1, the upper flange surface is connected to the reactor, and the lower flange surface is connected to the external sampler.

[0048] It is worth noting that if Figure 2As shown, each port of the external sampler in an oblique three-way structure is installed with a ball valve. Specifically, ball valves are installed at the upper and lower ports of the straight pipe section 5 and the port of the oblique pipe section 6, respectively, so that the external sampler can obtain the empty sample and the normal sample and isolate the empty sample and the normal sample from the outside world.

[0049] It can be seen that the protective coating 2 on the outer surface of the internal sampling tube 1 can isolate the normal product of the reactor from the outer wall of the internal sampling tube 1, avoiding the introduction of metal impurities into the normal product, resulting in the contamination of the normal product with metal impurities. The protective coating or protective sleeve 3 on the inner diameter surface of the internal sampling tube 1 can isolate the sampled sample from the inner wall of the internal sampling tube 1, avoiding the introduction of metal impurities into the sampled sample, resulting in a large deviation in the detection results in terms of metal impurities.

[0050] The inner diameter surface of the external sampler has a protective coating 4, which can isolate the sampled sample from the inner wall of the external sampler to avoid the introduction of metal impurities into the sampled sample, resulting in a large deviation in the detection results in terms of metal impurities. The volume from the bifurcation of the external sampler's oblique tee structure to the bottom of the straight pipe section 5 is at least 1.2 times the internal volume of the internal sampling tube 1, ensuring that the remaining empty sample can be collected before sampling. After the sampling starts, the nitrogen exhaust port 9, the first nitrogen inlet 7 and the second nitrogen inlet 8 need to be opened. After the sample fills the oblique pipe section 6, the thermometer will rise suddenly, indicating that enough samples have been collected. After cooling to a certain temperature, the straight pipe section 5 collects the empty sample, and the oblique pipe section collects the normal sample for analysis and testing.

[0051] The above specific implementations do not constitute a limitation on the protection scope of the present invention. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions may occur depending on design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A bed sampling device, characterized in that: It includes an internal sampling tube and an external sampler; wherein the internal sampling tube extends into the interior of the bed layer and passes through the bottom of the reactor to be connected with the external sampler; the external sampler is an oblique three-way structure, and is provided with a nitrogen outlet and an inlet; The top of the straight pipe section of the external sampler oblique tee structure is connected to the internal sampling tube, the upper end of the straight pipe section of the external sampler oblique tee structure is provided with a nitrogen outlet, and the lower end of the straight pipe section and the oblique pipe section of the external sampler oblique tee structure are respectively provided with nitrogen inlets; The volume from the bifurcation of the oblique tee structure of the external sampler to the bottom end of the straight pipe section is greater than the volume of the internal sampling tube; The inner and outer diameter surfaces of the internal sampling tube have a protective coating or a protective sleeve, and the inner diameter surface of the external sampler has a protective coating.

2. The bed sampling device according to claim 1, characterized in that: include: A protective coating is provided partially or entirely on the outer diameter surface of the inner sampling tube.

3. The bed sampling device according to claim 1, characterized in that: include: The inner diameter surface of the internal sampling tube is provided with protective sleeves in sections or continuously, and the protective sleeves are closely fitted to the inner wall of the internal sampling tube.

4. The bed sampling device according to claim 1, characterized in that: include: Two layers of flange surfaces are arranged on the outer wall of the internal sampling tube, the upper flange surface is connected to the reactor, and the lower flange surface is connected to the external sampler.

5. The bed sampling device according to claim 1, characterized in that: include: Each port of the external sampler in an oblique three-way structure is equipped with a ball valve.

6. The bed sampling device according to any one of claims 1 to 5, characterized in that: include: A plurality of thermometers are respectively distributed at different heights of the inclined pipe section of the inclined tee structure of the external sampler.

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