Heating device for particle silicon digestion

Abstract

The utility model discloses a heating device for particle silicon digestion, which comprises a device body, and the device body comprises a top wall and a cavity arranged below the top wall; the top wall is provided with more than two digestion container heating placement areas which are arranged at intervals and a ventilation area positioned outside the digestion container heating placement areas, and the ventilation area is communicated with the inside and the outside of the cavity; the device body is provided with a suction opening, and the suction opening is communicated with the cavity. When the suction opening sucks air, negative pressure is formed in the cavity, smoke generated by heating and melting enters the cavity through the ventilation area, and the smoke in the cavity is sucked away through the suction opening. Therefore, smoke generated by heating ablation is prevented from staying in the heating placement area of the digestion container for a long time, so that the probability of mutual influence among samples contained in different digestion containers is reduced, and the detection accuracy is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of granular silicon digestion, in particular to a heating device for granular silicon digestion. Background Art

[0002] Granular silicon is the primary material for solar cells. Metallic impurities in silicon can affect the electrical, mechanical, thermal, and chemical properties of the wafer. For example, when trace amounts of phosphorus are added to silicon, its electrical conductivity significantly increases because phosphorus has excess electrons, which enhances conductivity. Furthermore, impurities and defects, such as interstitial atoms, precipitates, and dislocations of transition metals, introduce energy levels into the silicon. The closer these energy levels are to the Fermi level, the greater the recombination cross-section for charge carriers, resulting in more severe carrier recombination, which can significantly reduce the battery's voltage and current, impacting electrical performance.

[0003] Moreover, the presence of impurities will introduce lattice defects, resulting in changes in the mechanical properties of the material, such as strength, toughness, and hardness. For example, when a small amount of carbon impurities is added to a metal material, it will form a carbide phase, which will significantly increase the hardness of the material. However, in some cases, the presence of impurities may also cause the material to become brittle and reduce its toughness. The addition of impurities can change the thermal performance parameters of the material, such as thermal conductivity and thermal expansion coefficient. For example, adding an appropriate amount of aluminum oxide to a ceramic material can improve its refractory properties and improve its application performance in high-temperature environments. When there are too many oxygen-containing impurities in a metal material, the thermal conductivity of the material may decrease.

[0004] The addition of some impurities can also alter the chemical properties of a material, such as its catalytic activity. For example, adding an appropriate amount of cerium to a catalyst can improve its efficiency. Furthermore, certain impurities can affect a material's corrosion resistance and alter its environmental stability.

[0005] Detecting trace impurities in granular silicon is a crucial tool for determining and controlling impurity levels. Currently, in laboratories, this requires pre-digestion of the granular silicon using a concentrated acid mixture, which reacts with the granular silicon to produce a large amount of yellow smoke. This process involves the hydrofluoric acid reacting with silicon to form silicon tetrafluoride, which is then expelled from the silicon. The remaining granular silicon is then tested for impurities.

[0006] To accelerate the reaction between the acid and granular silicon and shorten the reaction time, the acid and granular silicon mixture is usually heated and evaporated to dryness. This process requires the use of high-temperature resistant containers and corrosion-resistant heating plates.

[0007] Currently, the heating plate used is the American Labtech EG20BT. This type of heating plate can heat the samples well, but it cannot effectively discharge the yellow smoke generated during the reaction between granular silicon and concentrated acid. It can only rely on the downward pressure of the air flow in the Class 100 fume hood. However, the current heating plate is a whole-piece heating plate and does not allow the yellow smoke to pass through in time, which causes the yellow smoke to stay in the samples for a long time, increases the probability of mutual influence between samples, and reduces the detection accuracy. In addition, this heating plate cannot fix the intervals between individual samples, and it may cause cross-contamination between samples due to human reasons, such as placing two samples close to each other.

[0008] Therefore, currently, the heating plate is usually placed in the fume hood. When in use, after completely removing the yellow smoke from the ablation container in other ventilated areas of the fume hood, it is then transferred to the heating plate for heating and evaporation to dryness. This transfer process is likely to introduce impurities, thereby reducing the detection accuracy.

[0009] In the current granular silicon market, the impurity content in granular silicon has been reduced to less than 3 ppb, and the requirements for environmental and facility cleanliness are extremely high. Any small error can lead to inaccurate sample detection. The above-mentioned heating plate can no longer meet the usage requirements.

[0010] The information disclosed in this background art section is only intended to increase the understanding of the overall background of the present utility model, and should not be regarded as an admission or any form of implication that this information constitutes the prior art already known to those of ordinary skill in the art. Summary of the Utility Model

[0011] Object of the Utility Model: The technical problem to be solved by the present utility model is to provide a heating device for granular silicon digestion, which has higher trace impurity detection accuracy, aiming at the deficiencies of the prior art.

[0012] To solve the above technical problems, the present utility model discloses a heating device for granular silicon digestion, which includes a device body. The device body includes a top wall and a cavity provided below the top wall. The top wall is provided with two or more digestion container heating and placement areas arranged at intervals and a ventilation area located outside the digestion container heating and placement areas. The ventilation area communicates the inside and outside of the cavity. The device body is provided with an air extraction port, and the air extraction port communicates with the cavity.

[0013] When the air extraction port extracts air, a negative pressure is formed inside the cavity, and the smoke generated by heating and ablation enters the cavity through the ventilation area. The smoke in the cavity is drawn away through the air extraction port. Thus, it is avoided that the smoke generated by heating and ablation stays in the digestion container heating and placement areas for a long time, thereby reducing the probability of mutual influence between the samples contained in different digestion containers, and thus improving the detection accuracy.

[0014] Specifically, the device body is a hollow housing, and its inner wall defines the cavity.

[0015] Specifically, the device body includes two side walls connected to and opposite to the top wall, and the two side walls are respectively provided with the air extraction openings.

[0016] Specifically, a heating component is provided in the heating placement area of the digestion container.

[0017] More specifically, the heating component is a resistive heating element.

[0018] Further, the device further includes a protective cover for the resistive heating element, and the protective cover for the resistive heating element is disposed in the cavity and covers the outside of the resistive heating element.

[0019] In this embodiment, a protective cover for the resistive heating element is provided, and the protective cover for the resistive heating element can protect the resistive heating element from being corroded by chemical reagents such as acids and alkalis in the flue gas, thereby increasing the continuous working time of the device.

[0020] Specifically, a plurality of through holes are provided in the breathable area of the top wall of the device body.

[0021] Specifically, the device further includes an exhaust fan group, and the exhaust fan group is connected to the air extraction opening.

[0022] Specifically, the exhaust fan group is installed on the side wall of the device body.

[0023] Specifically, the inner wall of the cavity is provided with an acid and alkali resistant anti-corrosion coating.

[0024] Further, a protrusion for limiting the digestion container is further provided at the edge of the heating placement area of the digestion container.

[0025] Beneficial effects:

[0026] 1) The heating device for granular silicon digestion disclosed by the present utility model, while heating and melting the container in the heating placement area of the digestion container, timely extracts the flue gas generated by the melting, avoiding the long-term stay of the flue gas in the heating placement area of the digestion container, thereby reducing the probability of mutual influence between the samples contained in different digestion containers, and thus improving the detection accuracy. Compared with the prior art, the device completes the functions of extracting yellow smoke and heating at the same station, without transferring the melting container, avoiding the problem of reduced detection accuracy caused by human factors introducing impurities, and at the same time improving the work efficiency.

[0027] 2) By providing heating placement areas for the digestion containers that are spaced apart from each other, the present utility model fixes the interval between the digestion containers, allowing different samples to be processed on the same heating device, and improving the sample analysis efficiency.

[0028] 3) Further, by providing a protrusion for limiting the digestion container at the edge of the heating and placing area of the digestion container, the interval between the digestion containers is fixed, avoiding problems such as cross-contamination between samples caused by placing two samples close to each other. Description of the Drawings

[0029] The following further specifically describes the present utility model in conjunction with the drawings and specific embodiments, and the above and / or other advantages of the present utility model will become clearer.

[0030] Figure 1 It is a schematic internal structure diagram of a heating device for digesting granular silicon disclosed by the present utility model.

[0031] Figure 2 is Figure 1 a top view of the heating device for digesting granular silicon shown.

[0032] Description of the reference numerals:

[0033] 1. Device body; 11. Top wall; 111. Heating and placing area for digestion container; 1111. Heating component; 112. Venting area; 113. Protrusion; 12. Cavity; 13. Side wall; 131. Air extraction port; 2. Resistance heating element protection cover; 3. Exhaust fan group; 4. Digestion container. Specific Embodiments

[0034] Refer to Figures 1 to 2 , the present utility model discloses a heating device for digesting granular silicon, which includes a device body 1. The device body 1 includes a top wall 11 and a cavity 12 provided below the top wall 11. The top wall 11 is provided with two or more spaced-apart heating and placing areas 111 for digestion containers and a venting area 112 located outside the heating and placing areas 111 for digestion containers. The venting area 112 communicates the inside and outside of the cavity 12. The device body 1 is provided with an air extraction port 131, and the air extraction port 131 communicates with the cavity 12.

[0035] Refer to Figure 1 , Figure 1 The hollow arrows in represent the flow direction of the flue gas. When the air extraction port 131 extracts air, a negative pressure is formed inside the cavity 12, and the flue gas generated by heating and ablation enters the cavity 12 through the venting area 112. The flue gas in the cavity 12 is extracted through the air extraction port 131. Thus, it is avoided that the flue gas generated by heating and ablation stays in the heating and placing area of the digestion container for a long time, thereby reducing the probability of mutual influence between the samples contained in different digestion containers 4, and thus improving the detection accuracy.

[0036] Ablation and heating can be carried out in steps or simultaneously.

[0037] In this application, the sample contained in the digestion container 4 is a mixture of granular silicon and a digestion solution.

[0038] Specifically, referring to Figure 1 , the device body 1 is a hollow housing, and a cavity 12 is defined inside it.

[0039] Specifically, referring to Figure 1 , the device body 1 includes two side walls 13 connected to and oppositely arranged with the top wall 11, and air extraction openings 131 are respectively formed in the two side walls 13.

[0040] Specifically, referring to Figure 1 , a heating component 1111 is provided in the digestion container heating placement area 111.

[0041] More specifically, referring to Figure 1 , the heating component 1111 is a resistance heating element such as an electric heating tube, etc., or a PTC heating element.

[0042] It should be understood that other heating elements that can be used for heating and do not precipitate impurities can be used in this embodiment.

[0043] Further, referring to Figure 1 , the device further includes a resistance heating element protection cover 2, and the resistance heating element protection cover 2 is arranged in the cavity 12 and covers the outside of the resistance heating element.

[0044] In this embodiment, a resistance heating element protection cover 2 is provided, and the resistance heating element protection cover 2 can protect the resistance heating element from being corroded by chemical reagents such as acids and alkalis in the flue gas, thereby increasing the continuous working time of the device.

[0045] Specifically, referring to Figure 1 , a plurality of through holes 1121 are provided in the air permeable area 112 of the top wall 11 of the device body 1.

[0046] Specifically, referring to Figure 1 , the device further includes an exhaust fan group 3, and the exhaust fan group 3 is connected to the air extraction openings 131.

[0047] Specifically, referring to Figure 1 , the exhaust fan group 3 is installed on the side wall of the device body 1.

[0048] Specifically, the inner wall of the cavity 12 is provided with an acid and alkali resistant anti-corrosion coating.

[0049] Further, referring to Figure 1 , a protrusion 113 for limiting the digestion container is further provided at the edge of the digestion container heating placement area 111. The protrusion 113 can be a complete ring or incomplete.

[0050] More specifically, the size of the top wall 11 is 400mm * 600mm. The heating and placement area 111 of the digestion container is a circular area with a diameter of 30mm. The interval between the central positions of two adjacent heating and placement areas 111 of the digestion container is 60mm. The height of the protrusion 113 from the top wall 11 is 0.5mm.

[0051] The present invention provides an idea and method for a heating device for granular silicon digestion. There are many methods and ways to specifically implement this technical solution. The above is only the preferred embodiment of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention. Each component not clearly defined in this embodiment can be implemented by the prior art.

Claims

1. A heating device for the digestion of granular silicon, characterized in that, It includes a device body (1), and the device body (1) includes a top wall (11) and a cavity (12) disposed below the top wall (11); the top wall (11) is provided with two or more digestion container heating and placing areas (111) spaced apart from each other and a ventilation area (112) located outside the digestion container heating and placing areas (111), and the ventilation area (112) communicates the inside and outside of the cavity (12); the device body (1) is provided with an air extraction port (131), and the air extraction port (131) communicates with the cavity (12).

2. The heating device for silicon particle digestion according to claim 1, characterized in that, The device body (1) is a hollow shell, and its inner wall defines the cavity (12).

3. The heating device for silicon particle digestion according to claim 1, wherein The device body (1) includes two side walls (13) connected to and oppositely disposed with the top wall (11), and the two side walls (13) are respectively provided with the air extraction port (131).

4. The heating device for granular silicon digestion according to claim 1, characterized in that, The digestion container heating and placing area (111) is provided with a heating assembly (1111).

5. The heating device for granulated silicon digestion according to claim 4, wherein, The heating assembly (1111) is a resistance heating element or a PTC heating element.

6. The heating device for silicon particle digestion according to claim 5, wherein, It further includes a resistance heating element protection cover (2), and the resistance heating element protection cover (2) is disposed in the cavity (12) and covers the outside of the resistance heating element.

7. The heating device for granulated silicon digestion according to claim 1, characterized in that, The ventilation area (112) in the top wall (11) of the device body (1) is provided with a plurality of through holes (1121).

8. The heating device for granulated silicon digestion according to claim 1, characterized in that, It further includes an air extraction fan group (3), and the air extraction fan group (3) is connected to the air extraction port (131); the air extraction fan group (3) is installed on the side wall of the device body (1).

9. The heating device for silicon particle digestion according to claim 1, wherein, The inner wall of the cavity (12) is provided with an acid and alkali resistant anti-corrosion coating.

10. The heating device for silicon particle digestion according to claim 1, characterized in that, A protrusion (113) for limiting the digestion container is further provided at the edge of the digestion container heating and placing area (111).

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