Tertiary amine resin treatment system for polycrystalline silicon production

Abstract

A tertiary amine resin treatment system for polycrystalline silicon production. An upper part of a spray tower (1) is provided with a spray mechanism (1-1); a packing layer (1-2) of the spray tower (1) is located below the spray mechanism (1-1) and is used to absorb gases volatilized from a tower bottom portion of the spray tower (1); the tower bottom portion of the spray tower (1) is in communication with a resin feeding pipe (1-3); a nitrogen pressure-supplementing pipe (1-4) is connected to the resin feeding pipe (1-3); feeding ports of centrifuges (2) are in communication with a discharging port of the spray tower (1); two centrifuges (2) are distributed in parallel; an inlet of a liquid container (5) is in communication with liquid outlets of the centrifuges (2); a water inlet (5-1) and a neutralization solution inlet (5-2) are disposed in the liquid container (5); an input end of a canned motor pump (6) is in communication with the liquid container (5); an output end of the canned motor pump (6) is in communication with the spray mechanism (1-1); a drum dryer (4) is configured to dry solid materials obtained after dewatering in the centrifuges (2); and an overhead crane (3) hoists the materials to the drum dryer (4) by means of filter cloths of the centrifuges (2).

Description

A tertiary amino resin processing system for polysilicon production Technical Field

[0001] The present invention relates to the field of polysilicon production equipment, in particular to a tertiary amino resin processing system for polysilicon production. Background Art

[0002] Tertiary amino resin is a resin that can be used as both a catalyst for the anti-disproportionation reaction and an adsorbent for impurity removal in the improved Siemens polysilicon production process. Its main performance as a catalyst is to catalyze the following reactions:

[0003] When used as an adsorbent, the main performance of tertiary amino groups is to adsorb impurities containing B and P elements. Tertiary amino resins have excellent catalytic and adsorption properties, but their disadvantage is that they are non-renewable. After a certain period of use, their adsorption and impurity removal performance will significantly decrease. At this time, a new batch of tertiary amino resins needs to be replaced to maintain stable production operations, and the original tertiary amino resins must be replaced and discharged. After replacement and discharge, the internal structure of the tertiary amino resin still adsorbs chlorosilanes and impurities containing B and P elements; the most common treatment method is to pass the tertiary amino resin into water. The chlorosilanes and impurities containing B and P elements adsorbed in the resin react with water to produce products such as silicon dioxide, hydrogen chloride (which becomes hydrochloric acid when dissolved in water), and hydrogen. This reaction is commonly known as hydrolysis reaction. The hydrolyzed resin is dried and bagged for disposal as hazardous waste. Common hydrolysis equipment is ton barrels or water tanks. After the production water is injected into the hydrolysis equipment, the tertiary amino resin is then injected. After it is fully hydrolyzed, the tertiary amino resin and water are separated by gravity using a filter. The separated acidic water is sent to the waste treatment section. The tertiary amino resin is manually cleaned from the hydrolysis equipment, air-dried, and then bagged. However, this treatment method is inefficient. During the hydrolysis process, the chlorosilanes adsorbed within the tertiary amino resin react with water to release large amounts of hydrogen chloride, which seriously harms human health and pollutes the environment. Furthermore, relying on gravity filtration increases time costs, and drying the resin is affected by weather. It also requires a large area, which takes up production space. Summary of the Invention

[0004] In view of this, the present invention provides a tertiary amino resin processing system for polysilicon production, the main purpose of which is to improve the processing efficiency of tertiary amino resin, reduce the volatilization of harmful gases, and improve the working environment of operators.

[0005] To achieve the above objectives, the present invention mainly provides the following technical solutions:

[0006] An embodiment of the present invention provides a tertiary amino resin processing system for polysilicon production, comprising: a spray tower, a centrifuge, a liquid container, a shielded pump, a drum dryer, and a crane;

[0007] The upper part of the spray tower is provided with a spray mechanism;

[0008] The top of the spray tower is provided with a vent;

[0009] The packing layer of the spray tower is located below the spray mechanism and is used to absorb the volatilized gas from the bottom of the spray tower;

[0010] The bottom part of the spray tower has a resin feed port; the resin feed port is connected to a resin feed pipe; the resin feed pipe is connected to a nitrogen pressure-compensating pipe;

[0011] The feed port of the centrifuge is connected to the discharge port of the spray tower; a filter cloth is provided in the centrifuge for wrapping the material to be deliquated;

[0012] There are two centrifuges; the two centrifuges are distributed in parallel;

[0013] The inlet of the liquid container is in communication with the liquid outlet of the centrifuge;

[0014] The liquid container is provided with a water inlet;

[0015] The liquid container is provided with a neutralizing liquid inlet;

[0016] The input end of the shielded pump is connected to the liquid container; the output end of the shielded pump is connected to the spray mechanism;

[0017] The drum dryer is used to dry the solid material after the centrifuge removes the liquid;

[0018] The crane lifts the solid material after deliquoring in the centrifuge to the drum dryer through the filter cloth.

[0019] Furthermore, the two centrifuges are respectively connected to the discharge port of the spray tower through a conveying pipeline; and a shut-off valve is provided on the conveying pipelines of the two centrifuges.

[0020] Furthermore, the drum dryer comprises: a heat exchanger and a drum drying device;

[0021] The tube side of the heat exchanger is used to heat the compressed air;

[0022] The shell side of the heat exchanger is connected to the condensate system of the distillation tower for the circulation of steam condensate;

[0023] The drum drying device is connected to the pipe side of the heat exchanger, and is used for the heated compressed air to flow in to achieve material drying.

[0024] Furthermore, a resin collecting container is provided at the output end of the drum drying device for collecting the dried tertiary amino resin.

[0025] Furthermore, the spray tower has at least two packing layers.

[0026] By means of the above technical solution, the tertiary amino resin treatment system for polysilicon production of the present invention has at least the following advantages:

[0027] It can improve the processing efficiency of tertiary amino resin, reduce the volatilization of harmful gases, improve the working environment of operators, save drying space, and is not affected by weather.

[0028] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention and implement it according to the contents of the specification, the following is a detailed description of the preferred embodiments of the present invention with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] FIG1 is a schematic diagram of a tertiary amino resin processing system for polysilicon production provided by an embodiment of the present invention.

[0030] As shown in the figure:

[0031] 1 is a spray tower, 1-1 is a spray mechanism, 1-2 is a packing layer, 1-3 is a resin feed pipe, 1-4 is a nitrogen pressure boosting pipe, 2 is a centrifuge, 3 is a crane, 4 is a drum dryer, 4-1 is a feeding hopper, 4-2 is a feed conveyor, 4-3 is a drying drum, 4-4 is a cyclone separator, 4-5 is a discharge conveyor, 4-6 is a heat exchanger, 5 is a liquid container, 5-1 is a water inlet, 5-2 is a neutralizing liquid inlet, 6 is a shielded pump, and 7 is a resin collection container. DETAILED DESCRIPTION

[0032] To further illustrate the technical means and effects employed by the present invention to achieve its intended objectives, the following detailed description of the specific implementation methods, structures, features, and effects of the present invention is provided in conjunction with the accompanying drawings and preferred embodiments. In the following description, different references to "one embodiment" or "embodiment" do not necessarily refer to the same embodiment. Furthermore, specific features, structures, or characteristics of one or more embodiments may be combined in any suitable manner.

[0033] As shown in FIG1 , one embodiment of the present invention provides a tertiary amino resin processing system for polysilicon production, comprising: a spray tower 1, a centrifuge 2, a liquid container 5, a shielded pump 6, a drum dryer 4, and a crane 3. The upper portion of the spray tower 1 is provided with a spray mechanism 1-1 for spraying water onto a packing layer 1-2 and the bottom of the tower. The top of the spray tower 1 is provided with a vent for venting hydrogen and other gases. The packing layer 1-2 of the spray tower 1 is located below the spray mechanism 1-1 and is used to absorb volatile gases from the bottom of the spray tower 1. Chlorosilane reacts with water to release a large amount of hydrogen chloride, most of which dissolves in water. A small amount of volatile gas is absorbed by the spray liquid on the wetted packing surface, preventing the discharge of volatiles and avoiding environmental pollution. The bottom part of the spray tower 1 has a resin feed port for the resin to be treated to enter; the resin feed port is connected to a resin feed pipe 1-3 for the resin to be treated to enter; the resin feed pipe 1-3 is connected to a nitrogen pressure-boosting pipe 1-4 for promoting the resin to enter the spray tower 1.

[0034] The feed inlet of centrifuge 2 is connected to the discharge outlet of spray tower 1. A filter cloth is installed inside centrifuge 2 to wrap the material to be dehydrated. The mixture of tertiary amino resin and water after the hydrolysis reaction enters centrifuge 2 for dehydration. Two centrifuges 2 are arranged in parallel, allowing them to be used alternately, ensuring continuous operation of spray tower 1. This eliminates the need to discharge the tertiary amino resin in batches, significantly saving time and costs. Preferably, the two centrifuges 2 are connected to the discharge outlet of spray tower 1 via separate delivery pipes. Both delivery pipes are equipped with shut-off valves to facilitate automatic control.

[0035] The inlet of the liquid container 5 is communicated with the liquid outlet of the centrifuge 2 for receiving the liquid discharged from the centrifuge 2 .

[0036] Liquid container 5 is provided with a water inlet 5-1 for adding water to maintain a normal liquid level. A neutralizing liquid inlet 5-2 is provided for adding dilute NaOH solution to maintain the pH of the liquid level within liquid container 5. During the initial stage, process water is injected into liquid container 5. This water is consumed due to contact with the tertiary amino resin and a hydrolysis reaction. The hydrogen chloride generated by the hydrolysis reaction dissolves in the water to form hydrochloric acid. Therefore, the water returned from centrifuge 2 to liquid container 5 is acidic, and the amount of water is reduced. Depending on the liquid level and pH value within liquid container 5, process water or a small amount of dilute NaOH solution must be added promptly to maintain a normal liquid level and a neutral pH within liquid container 5.

[0037] The input end of the canned motor pump 6 is connected to the liquid container 5; the output end of the canned motor pump 6 is connected to the spray mechanism 1-1, continuously delivering the neutralized liquid in the liquid container 5 to the spray mechanism 1-1, thereby recycling the liquid in the liquid container 5. The drum dryer 4 is used to dry the solid material after the centrifuge 2 removes the liquid. The crane 3 lifts the solid material removed from the centrifuge 2 to the drum dryer 4 through the filter cloth. The crane 3 lifts the removed solid material to the drum dryer 4 for drying before discharging it.

[0038] An embodiment of the present invention provides a tertiary amino resin processing system for polysilicon production, which can improve the processing efficiency of tertiary amino resin, reduce the volatilization of harmful gases, improve the working environment of operators, save drying space, and is not affected by weather.

[0039] As a preferred embodiment of the above embodiment, drum dryer 4 includes: a heat exchanger 4-6 and a drum drying device. The tube side of heat exchanger 4-6 is used to heat compressed air. The shell side of heat exchanger 4-6 is connected to the condensate system of the distillation tower for the circulation of steam condensate. The steam condensate is used to heat the compressed air, recovering the energy of the steam condensate, thereby achieving energy conservation and consumption reduction. The drum drying device is connected to the tube side of heat exchanger 4-6, allowing the heated compressed air to flow in and dry the material. Drum dryer 4 does not require a large area for drying resin in the sun, thus avoiding weather conditions. It also eliminates the need for spreading and turning the resin, saving labor costs. Preferably, a resin collection container 7 is provided at the output end of the drum drying device for collecting the dried tertiary amino resin. The drum drying device includes: a hopper 4-1, a feed conveyor 4-2, a drying drum 4-3, a discharge conveyor 4-5, and a cyclone separator 4-4. The hopper 4-1 is used for temporary storage of material. The feed conveyor 4-2 is used to transport the material in the hopper 4-1 to the drying drum 4-3, and the discharge conveyor 4-5 is used to output the dried material; the cyclone separator 4-4 is used to achieve solid-gas separation.

[0040] As a preference of the above embodiment, the packing layers 1-2 of the spray tower 1 are at least two layers, so as to fully absorb the volatiles.

[0041] One embodiment of the present invention provides a tertiary amino resin processing system for polysilicon production. The specific operating process is as follows: sufficient production water is added to a liquid container 5; the vent at the top of a spray tower 1 is opened; a shielded pump 6 delivers the production water from the liquid container 5 to the spray tower 1. The spray water passes through packing layers 1-2 and reaches the bottom of the spray tower 1. When the bottom of the spray tower 1 reaches a certain liquid level, the tertiary amino resin to be hydrolyzed is introduced through the resin feed port of the spray tower 1. A nitrogen booster pipe 1-4 is opened to facilitate the entry of the tertiary amino resin into the spray tower 1. The feed rates of the tertiary amino resin and spray water are adjusted to maintain a slurry-like mixture in the bottom of the spray tower 1, thereby ensuring sufficient hydrolysis. After the tertiary amino resin fully contacts the water in the bottom of the spray tower 1, it reacts to generate a large amount of hydrogen chloride and a small amount of hydrogen. The gas fully contacts the spray water on the packing layers 1-2 of the spray tower 1, dissolving the hydrogen chloride in the spray water. The hydrogen is discharged from the vent at the top of the spray tower 1. The discharge port of spray tower 1 is opened, and the slurry mixture of tertiary amino resin and water enters centrifuge 2. Centrifuge 2 is turned on to separate the tertiary amino resin and acid water, and the acid water is returned to liquid container 5. When the tertiary amino resin in centrifuge 2 reaches the designed amount, the other centrifuge 2 is switched to operate. The two centrifuges 2 can be used interchangeably. The filter cloth wrapped around the separated tertiary amino resin in centrifuge 2 is lifted by crane 3 and transported to drum dryer 4. The tertiary amino resin enters drum dryer 4's hopper 4-1. The feed conveyor 4-2 conveys the tertiary amino resin to the upper portion of drying drum 4-3. Compressed air, after being heated by heat exchanger 4-6, enters the lower portion of drying drum 4-3, fully contacts the dried tertiary amino resin, and removes any moisture it carries. Most of the dried tertiary amino resin is directly discharged from discharge conveyor 4-5. A small portion enters cyclone separator 4-4 with compressed air, undergoes gas-solid phase separation, and the compressed air is discharged from the top of cyclone separator 4-4. The tertiary amino resin falls into the hopper of cyclone separator 4-4 and enters discharge conveyor 4-5. Discharge conveyor 4-5 delivers the dried resin to dry resin collection container 7.

[0042] In the description of the present invention, unless otherwise expressly specified or limited, the terms "mounted," "connected," "connected," and "fixed" should be understood in a broad sense. For example, they may refer to fixed connection, detachable connection, or integration; mechanical connection or electrical connection; direct connection or indirect connection through an intermediate medium; and internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention in specific circumstances.

[0043] The standard parts used in the present invention can all be purchased from the market, and special-shaped parts can be customized according to the description in the specification and the drawings. The specific connection methods of each part adopt conventional means such as mature bolts, rivets, welding, etc. in the existing technology. The machinery, parts and equipment all adopt 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.

[0044] The above description is merely a preferred embodiment of the present invention and does not constitute any form of limitation to the present invention. Any simple modifications, equivalent changes and modifications made to the above embodiment 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 tertiary amino resin processing system for polysilicon production, characterized in that: Including: spray tower, centrifuge, liquid container, shielded pump, drum dryer and crane; The upper part of the spray tower is provided with a spray mechanism; The top of the spray tower is provided with a vent; The packing layer of the spray tower is located below the spray mechanism and is used to absorb the volatilized gas from the bottom of the spray tower; The bottom part of the spray tower has a resin feed port; the resin feed port is connected to a resin feed pipe; the resin feed pipe is connected to a nitrogen pressure-compensating pipe; The feed port of the centrifuge is connected to the discharge port of the spray tower; a filter cloth is provided in the centrifuge for wrapping the material to be deliquated; There are two centrifuges; the two centrifuges are distributed in parallel; The inlet of the liquid container is in communication with the liquid outlet of the centrifuge; The liquid container is provided with a water inlet; The liquid container is provided with a neutralizing liquid inlet; The input end of the shielded pump is connected to the liquid container; the output end of the shielded pump is connected to the spray mechanism; The drum dryer is used to dry the solid material after the centrifuge removes the liquid; The crane lifts the solid material after deliquoring in the centrifuge to the drum dryer through the filter cloth.

2. The tertiary amino resin processing system for polysilicon production according to claim 1, characterized in that: The two centrifuges are respectively communicated with the discharge port of the spray tower through a conveying pipeline; and a shut-off valve is provided on the conveying pipelines of the two centrifuges.

3. The tertiary amino resin processing system for polysilicon production according to claim 1, characterized in that: The drum dryer comprises: a heat exchanger and a drum drying device; The tube side of the heat exchanger is used to heat the compressed air; The shell side of the heat exchanger is connected to the condensate system of the distillation tower for the circulation of steam condensate; The drum drying device is connected to the pipe side of the heat exchanger, and is used for the heated compressed air to flow in to achieve material drying.

4. The tertiary amino resin processing system for polysilicon production according to claim 3, characterized in that: The output end of the drum drying device is provided with a resin collecting container for collecting the dried tertiary amino resin.

5. The tertiary amino resin processing system for polysilicon production according to claim 1, characterized in that: The spray tower has at least two packing layers.

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