Water cooling screen structure for single crystal furnace

Abstract

The utility model relates to a water-cooling screen structure for a single crystal furnace, which structurally comprises a water-cooling screen body, a circulating water inlet and a circulating water outlet are arranged on the water-cooling screen body, and a flowing working medium in the water-cooling screen body is a carbon nano tube-sodium dodecyl benzene sulfonate solution. A flowing working medium in the water cooling screen body is replaced by the carbon nano tube-sodium dodecyl benzene sulfonate solution from pure water, and compared with pure water, carbon nano tubes have better heat exchange performance and can effectively enhance heat conductivity. The water-cooling screen has the advantages that the structural design is reasonable, and compared with pure water in the prior art, the carbon nano tube-sodium dodecyl benzene sulfonate solution is introduced into the water-cooling screen body, so that the heat conduction performance of a flowing working medium in the water-cooling screen can be improved, the heat exchange performance of the water-cooling screen is further improved, and the crystal bar production rate is effectively improved.

Description

Technical Field

[0001] The utility model relates to a water cooling screen structure for a single crystal furnace, belonging to the technical field of single crystal furnaces. Background Art

[0002] In the photovoltaic monocrystalline silicon growth industry, the process of pulling the crystal rod is the process of liquid silicon solidifying into solid monocrystalline silicon. The water cooling screen is an important structure of the single crystal furnace, which is used to cool the crystal rod, reduce the crystal rod temperature, and speed up the growth of the crystal rod. The cooling performance of the water cooling screen is closely related to the pulling rate of silicon single crystal.

[0003] In the prior art, the heat dissipation performance of the water cooling screen is generally optimized by changing the structure of the water cooling screen, such as designing double-layer water cooling, optimizing the flow channel in the water cooling screen, etc. The flowing medium in the water cooling screen is pure water. The above improvement measures still cannot meet the growing demand for increasing the production rate of crystal rods.

[0004] Consider optimizing the thermal conductivity of the flowing working fluid in the water-cooled shield to further improve the heat exchange performance of the water-cooled shield and achieve a more efficient crystal rod production rate.

[0005] Carbon nanotube suspension is a new type of fluid, specifically carbon nanotube-sodium dodecylbenzene sulfonate solution, which has the following advantages: 1) Carbon nanoparticles have high thermal conductivity, which can enhance the thermal conductivity of the fluid; 2) Carbon nanoparticles have small particle size and large specific surface area, which can increase the heat exchange area with the base fluid; 3) The irregular movement of carbon nanoparticles in the suspension can enhance disturbance and convection heat transfer; 4) Sodium dodecylbenzene sulfonate solute is added to the circulating water to prevent the precipitation of carbon nanotubes to prepare a sodium dodecylbenzene sulfonate solution, which can make the carbon nanotube particles highly dispersed and stable in the solution. Utility Model Content

[0006] The utility model proposes a water-cooling screen structure for a single crystal furnace, which aims to overcome the above-mentioned deficiencies in the prior art, further improve the heat exchange performance of the water-cooling screen, and thus achieve a more efficient crystal rod production rate.

[0007] The technical solution of the utility model is a water-cooled shield structure for a single crystal furnace, which includes a water-cooled shield body, a circulating water inlet and a circulating water outlet are arranged on the water-cooled shield body, and the flowing working fluid in the water-cooled shield body is a carbon nanotube-sodium dodecylbenzene sulfonate solution. The flowing working fluid in the water-cooled shield body is replaced by a carbon nanotube-sodium dodecylbenzene sulfonate solution from pure water, and the carbon nanotube has better heat exchange performance than pure water, and can effectively enhance thermal conductivity.

[0008] Preferably, the outer side of the lower part of the water-cooled screen body is a guide tube, and below the guide tube is a quartz crucible filled with molten silicon, the outer side of the quartz crucible is wrapped with a carbon-carbon crucible, the upper part of the outer side of the carbon-carbon crucible is a main heater, the bottom of the carbon-carbon crucible is a graphite support rod, and below the top of the graphite support rod is a bottom heater, and both sides of the graphite support rod below the bottom heater are vacuum ports, and the guide tube, main heater, carbon-carbon crucible, graphite support rod, and bottom heater are wrapped with insulation felt as a whole, and the vacuum port is opened at the bottom of the insulation felt.

[0009] The advantages of the utility model are as follows: the structure is reasonably designed, and a carbon nanotube-sodium dodecylbenzene sulfonate solution is introduced into the water-cooling screen body. Compared with pure water in the prior art, the thermal conductivity of the flowing working fluid in the water-cooling screen can be improved, thereby improving the heat exchange performance of the water-cooling screen and effectively increasing the crystal rod production rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 The utility model is a structural schematic diagram of a water-cooling screen structure for a single crystal furnace.

[0011] In the figure, 1 is the water-cooled screen body, 11 is the circulating water inlet, 12 is the circulating water outlet, 2 is the guide tube, 3 is the quartz crucible, 4 is the silicon melt, 5 is the carbon-carbon crucible, 6 is the main heater, 7 is the insulation felt, 8 is the graphite support rod, 9 is the bottom heater, and 10 is the vacuum port. DETAILED DESCRIPTION

[0012] The present invention is further described in detail below in conjunction with embodiments and specific implementation methods.

[0013] like Figure 1 As shown, a water-cooled shield structure for a single crystal furnace comprises a water-cooled shield body 1, on which a circulating water inlet 11 and a circulating water outlet 12 are provided, the flowing working medium in the water-cooled shield body 1 is a carbon nanotube-sodium dodecylbenzene sulfonate solution, the outer side of the lower part of the water-cooled shield body 1 is a guide tube 2, below the guide tube 2 is a quartz crucible 3 filled with silicon melt 4, the outer side of the quartz crucible 3 is wrapped with a carbon-carbon crucible 5, the upper part of the outer side of the carbon-carbon crucible 5 is a main heater 6, the bottom of the carbon-carbon crucible 5 is a graphite support rod 8, below the top of the graphite support rod 8 is a bottom heater 9, and both sides of the graphite support rod 8 below the bottom heater 9 are vacuum ports 10, the guide tube 2, the main heater 6, the carbon-carbon crucible 5, the graphite support rod 8, and the bottom heater 9 are wrapped on the outer side of the insulation felt 7 as a whole, and the vacuum port 10 is opened at the bottom of the insulation felt 7.

[0014] According to the above structure, the flowing medium in the water-cooled screen body 1 is replaced by carbon nanotube-sodium dodecylbenzene sulfonate solution from pure water. This is because the thermal conductivity of carbon nanotubes is as high as about 3000w / m*k, which has better heat exchange performance than pure water and can effectively enhance thermal conductivity.

[0015] The mass fractions of sodium dodecylbenzene sulfonate and carbon nanotubes in the carbon nanotube-sodium dodecylbenzene sulfonate solution can be selected and adjusted according to the existing technology and production needs, and do not belong to the protection scope of the present utility model.

[0016] According to the prior art, when the mass fraction of sodium dodecylbenzene sulfonate is between 0 and 3 g / L -1 As the concentration of sodium dodecylbenzene sulfonate increases, the stability of the carbon nanotube fluid gradually increases. When the mass fraction of sodium dodecylbenzene sulfonate is greater than 3g / L -1 , the stability of the carbon nanotube fluid gradually weakens.

[0017] When the mass fraction of carbon nanotubes is between 0.5 and 5 g / L -1 , the mass fraction of sodium dodecylbenzene sulfonate is 3g / L -1 The increase in the mass fraction of carbon nanotubes gradually increases the thermal conductivity of the fluid (0.9%-15%). Considering that the water in the water-cooled screen is always in a state of continuous flow, it is preferred to use a carbon nanotube mass fraction of 5g / L. -1 , the mass fraction of sodium dodecylbenzene sulfonate is 3g / L -1 .

[0018] All the components mentioned above are prior art, and those skilled in the art can use any model and existing design that can achieve their corresponding functions.

[0019] The above is only a preferred embodiment of the present invention. It should be pointed out that a person skilled in the art can make several modifications and improvements without departing from the inventive concept of the present invention, and these modifications and improvements all fall within the protection scope of the present invention.

Claims

1. A water-cooling shield structure for a single crystal furnace, comprising a water-cooling shield body (1), the water-cooling shield body (1) being provided with a circulating water inlet (11) and a circulating water outlet (12), characterized in that: The working fluid flowing in the water-cooling screen body (1) is a carbon nanotube-sodium dodecylbenzene sulfonate solution; the outer side of the lower part of the water-cooling screen body (1) is a guide tube (2); below the guide tube (2) is a quartz crucible (3) containing a silicon melt (4); the outer side of the quartz crucible (3) is wrapped with a carbon-carbon crucible (5); the upper outer side of the carbon-carbon crucible (5) is a main heater (6); the bottom of the carbon-carbon crucible (5) is a graphite support rod (8); below the top of the graphite support rod (8) is a bottom heater (9); both sides of the graphite support rod (8) below the bottom heater (9) are vacuum ports (10); the guide tube (2), the main heater (6), the carbon-carbon crucible (5), the graphite support rod (8), and the bottom heater (9) are wrapped with a thermal insulation felt (7) as a whole; and the vacuum port (10) is opened at the bottom of the thermal insulation felt (7).

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