Tail gas emission system of boron diffusion equipment

Abstract

The utility model discloses a tail gas emission system of boron diffusion equipment, and belongs to the field of waste gas treatment. The tail gas emission system of the boron diffusion equipment comprises a cooling bottle and a water filtering unit, the cooling bottle is used for cooling the high-temperature waste gas and outputting the cooled waste gas; the water filtration unit is used for providing at least two stages of water filtration for the cooled waste gas, the water filtration unit is provided with a liquid inlet pipeline and a gas path, and the liquid inlet pipeline is isolated from the gas path. The device has more than two stages of filtration, B2O3, BCl3 and Cl2 generated by boron diffusion equipment can be filtered to the greatest extent, so that the gas [YT1] substances cannot reach the tail discharge pipe at the rear end, the problem that the B2O3 is deposited on the diaphragm and the tail discharge pipe is avoided, and the maintenance period and the maintenance cost are reduced. And meanwhile, the liquid inlet pipeline is isolated from the gas path, so that a series of problems caused by the fact that the liquid remains in the gas path and then enters a subsequent system are avoided.

Description

Technical Field

[0001] This application relates to the field of waste gas treatment, and particularly to an exhaust gas emission system for a boron diffusion equipment. Background Art

[0002] Currently, the boron diffusion equipment is a PN junction manufacturing equipment, which uses gaseous boron trichloride to diffuse silicon wafers in a diffusion furnace. Boron atoms enter the silicon wafers through diffusion, and at the same time, a layer of borosilicate glass layer is formed on the surface of the silicon wafers.

[0003] During the operation of the boron diffusion equipment, conventional cooling liquid accumulation devices and fiber filters are used for waste gas treatment. However, due to different mesh numbers of the filter screens of the fiber filter elements, it will also cause pressure on the load of the vacuum pump, and it is easy to increase the load due to blockage, or due to insufficient filtering ability, dust accumulates in the vacuum pump, resulting in the stuck failure of the vacuum pump. Therefore, it needs to be maintained frequently, and the maintenance cycle is generally 3 to 10 days. The maintenance frequency is high, and the consumption of exhaust gas emission accessories is large. The operation of the boron diffusion equipment will also be affected, resulting in unstable process pressure, poor film formation uniformity, and low product yield. Summary of the Utility Model

[0004] This application aims to solve at least one of the technical problems in the related art to some extent. For this reason, this application provides an exhaust gas emission system for a boron diffusion equipment.

[0005] This application provides an exhaust gas emission system for a boron diffusion equipment, including: a cooling bottle and a water filtration unit;

[0006] The cooling bottle is used to cool high-temperature waste gas and output the cooled waste gas;

[0007] The water filtration unit is used to provide at least two-stage water filtration for the cooled waste gas. The water filtration unit has a liquid inlet pipeline and a gas path, and the liquid inlet pipeline and the gas path are isolated from each other.

[0008] In the embodiment of this application, a non-filter element design is adopted, with more than two-stage filtration, which can filter B2O3, BCl3 and Cl2 generated by the boron diffusion equipment to the greatest extent, so that the above substances cannot reach the rear exhaust pipe, thereby avoiding the deposition problem of B2O3 on the diaphragm and the exhaust pipe, reducing the maintenance cycle and maintenance cost. At the same time, the liquid inlet pipeline and the gas path are isolated from each other, avoiding a series of problems caused by the liquid remaining in the gas path and then entering the subsequent system.

[0009] According to an embodiment of the present application, in the tail gas emission system of the boron diffusion equipment, the water filtration unit includes a first filtration bottle to an nth filtration bottle, where n is an integer greater than or equal to 2; the first filtration bottle to the nth filtration bottle are respectively used for the first-stage filtration to the nth-stage filtration of the cooled waste gas; a waste liquid outlet is further provided on the first filtration bottle, and a compressed air inlet is further provided on the nth filtration bottle. When compressed air enters the nth filtration bottle through the compressed air inlet, the liquid in the nth filtration bottle to the second filtration bottle can be pressed into the first filtration bottle and discharged through the waste liquid outlet. Thus, the filtered waste liquid is compressed by the compressed air and then flows backward, and finally enters the first filtration bottle and is discharged. The design of the backward flow can carry away the liquid remaining in the pipeline, and further avoid the accumulated waste liquid in the pipeline from entering the subsequent process.

[0010] According to an embodiment of the present application, in the tail gas emission system of the boron diffusion equipment, a short-circuit gas path is further included; the short-circuit gas path is connected in parallel with the pipeline where the first filtration bottle to the nth filtration bottle are located, and a short-circuit valve is provided on the short-circuit gas path. Thus, the water filtration unit can be short-circuited, and most of the waste gas directly reaches the subsequent process through the short-circuit gas path.

[0011] According to an embodiment of the present application, in the tail gas emission system of the boron diffusion equipment, the first filtration bottle satisfies: the first filtration bottle is provided with an inlet for waste gas before the first-stage filtration, an outlet for waste gas after the first-stage filtration, and a waste liquid outlet; wherein, the inlet for waste gas before the first-stage filtration is communicated with the outlet for cooled waste gas, allowing the cooled waste gas to enter the first filtration bottle for filtration, and the outlet for waste gas after the first-stage filtration is used for discharging the waste gas after the first-stage filtration.

[0012] According to an embodiment of the present application, in the tail gas emission system of the boron diffusion equipment, the nth filtration bottle satisfies: the nth filtration bottle is provided with an inlet for waste gas before the nth-stage filtration, an outlet for waste gas after the nth-stage filtration, and a compressed air inlet; wherein, the inlet for waste gas before the nth-stage filtration allows the waste gas after the (n - 1)th-stage filtration to enter for the nth-stage filtration, and the outlet for waste gas after the nth-stage filtration is used for discharging the waste gas after the nth-stage filtration.

[0013] According to an embodiment of the present application, in the tail gas emission system of the boron diffusion equipment, a diaphragm pump is connected to the outlet for waste gas after the nth-stage filtration, and a evacuation valve is provided on the pipeline between the diaphragm pump and the outlet for waste gas after the nth-stage filtration. Thus, the waste gas can be evacuated from the water filtration unit.

[0014] According to an embodiment of the present application, in the tail gas emission system of the boron diffusion equipment, a buffer bottle is further included; the buffer bottle is arranged between the cooling bottle and the first filtration bottle. Thus, it can play a role of secondary cooling during intake, and can also avoid excessive or uneven air flow when entering the water filtration unit.

[0015] In accordance with an embodiment of the present application, in the tail gas emission system of the boron diffusion equipment, a waste liquid outlet is connected to a waste liquid pipeline, and an acid discharge valve is provided on the waste liquid pipeline. Thus, the discharge of the waste liquid can be controlled.

[0016] In accordance with an embodiment of the present application, in the tail gas emission system of the boron diffusion equipment, a first filter liquid inlet to an nth filter liquid inlet are respectively provided on the first filter bottle to the nth filter bottle; the first filter liquid inlet to the nth filter liquid inlet are respectively connected to filter liquid pipelines, and a one-way valve is provided on each filter liquid pipeline. Thus, n-stage filtration is provided, and liquid backflow into the filter liquid pipelines is prevented.

[0017] In accordance with an embodiment of the present application, in the tail gas emission system of the boron diffusion equipment, when n≥3, a first filter liquid inlet to a (n - 1)th filter liquid inlet are respectively provided on the first filter bottle to the (n - 1)th filter bottle; the first filter liquid inlet to the (n - 1)th filter liquid inlet are respectively connected to filter liquid pipelines, and a one-way valve is provided on each filter liquid pipeline. Thus, (n - 1)-stage filtration is provided, and liquid backflow into the filter liquid pipelines is prevented. The nth filter bottle is used for gas-liquid separation of the waste gas.

[0018] In accordance with an embodiment of the present application, in the tail gas emission system of the boron diffusion equipment, the filter liquid includes water. Thus, substances in the waste gas that react with water are filtered out.

[0019] Additional aspects and advantages of the present application will be given in part in the following description, become apparent in part from the following description, or be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The above and / or additional aspects and advantages of the present application will become apparent and be readily understood from the description of the embodiments in conjunction with the following drawings, where:

[0021] Figure 1 is a schematic structural diagram according to some embodiments;

[0022] Figure 2 is a schematic structural diagram according to other embodiments.

[0023] Reference Numerals:

[0024] 1 - High-temperature diffusion furnace; 2 - Cooling bottle; 3 - Buffer bottle; 4 - Specialty gas valve; 5 - First filter bottle; 6 - One-way valve; 7 - Second filter bottle; 8 - Water valve; 9 - Short-circuit valve; 10 - Gas valve; 11 - Third filter bottle; 12 - Evacuation valve; 13 - Diaphragm pump; 14 - Acid discharge valve. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0025] Embodiments of the present application will be described in detail below. Examples of the embodiments are shown in the accompanying drawings, where the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to explain the present application, and should not be construed as limiting the present application.

[0026] The existing tail gas discharge system of the boron diffusion equipment has the following problems in the module design for treating boron diffusion waste gas: 1. The filter element can only filter larger B2O3 particles; 2. Due to the unsatisfactory filtering effect of the original boron diffusion tail gas discharge, the tail gas discharge pipeline is blocked and needs to be replaced and cleaned regularly (about every 10 - 15 days); 3. The diaphragm of the diaphragm pump will reduce its service life due to the deposition of residual B2O3; 4. The system is blocked by B2O3, affecting the operation time of the equipment and causing unstable process pressure; The tail gas has chlorine gas and boron oxide leakage, releasing microboric acid and hydrogen chloride gas in the air, which is corrosive and polluting, causing the metal parts of the tail gas discharge system equipment to rust, corrode and be vulnerable, and accelerating the electrical aging speed. The leaked gas is seriously harmful to the human body.

[0027] Accordingly, the present application proposes a tail gas discharge system for a boron diffusion equipment.

[0028] In some embodiments, referring to Figures 1 to 2 , a tail gas discharge system for a boron diffusion equipment includes: a cooling bottle 2 and a water filtration unit;

[0029] The cooling bottle 2 is used to cool high-temperature waste gas and output the cooled waste gas;

[0030] The water filtration unit is used to provide at least two stages of water filtration for the cooled waste gas. The water filtration unit has a liquid inlet pipeline and a gas path, and the liquid inlet pipeline and the gas path are isolated from each other.

[0031] The embodiments of the present application have more than two stages of filtration, making the filtration effect of the filtered waste gas better. At the same time, the liquid inlet pipeline and the gas path are isolated from each other, avoiding liquid remaining in the gas path and then entering the subsequent system.

[0032] It should be noted that the water filtration unit includes a plurality of sequentially connected water filtration bottles, and the water filtration bottles are used to filter out substances in the waste gas that react with water and dissolve in water.

[0033] In some embodiments, the exhaust gas emission system of the boron diffusion equipment includes a cooling bottle, a first filter bottle to an nth filter bottle, where n is an integer greater than or equal to 2; the cooling bottle is used to cool high-temperature exhaust gas and output the cooled exhaust gas; the first filter bottle to the nth filter bottle are respectively used for the first-stage filtration to the nth-stage filtration of the cooled exhaust gas; the first filter bottle is further provided with a waste liquid outlet, and the nth filter bottle is further provided with a compressed air inlet. When compressed air enters the nth filter bottle through the compressed air inlet, the liquid in the nth filter bottle to the second filter bottle can be pressed into the first filter bottle and discharged through the waste liquid outlet.

[0034] Thus, by using the water in the filter bottle to carry out a chemical reaction with the boron diffusion exhaust gas, B2O3, BCl3 and Cl2 generated by the boron diffusion equipment are filtered to the greatest extent, so that the above substances cannot reach the rear-end exhaust pipe, thereby avoiding the deposition problem of B2O3 on the diaphragm and the exhaust pipe, and reducing the maintenance period and maintenance cost. In addition, in the embodiments of the present application, the filtered waste liquid is compressed by compressed air and then flows backward, and finally enters the first filter bottle and is discharged. The design of the backward flow can take away the liquid remaining in the pipeline, and further avoid the accumulation of the residual waste liquid in the pipeline from entering the subsequent process.

[0035] It should be noted that in the production process, the temperature of the produced high-temperature exhaust gas can reach above 800 °C. After being cooled by the cooling bottle, the temperature is greatly reduced, and the temperature of the cooled exhaust gas is 150 °C, and then filtration is carried out.

[0036] In some embodiments, in combination Figures 1 to 2 viewed Figures 1 to 2 the exhaust gas emission systems of the boron diffusion equipment are all three-stage filtration, and n is all 3.

[0037] In some embodiments, the exhaust gas emission system of the boron diffusion equipment further includes a short-circuit gas path; the short-circuit gas path is connected in parallel with the pipeline where the first filter bottle to the nth filter bottle are located, and a short-circuit valve 9 is provided on the short-circuit gas path. Thus, when it is detected that the contents of B2O3, BCl3 and Cl2 in the exhaust gas are all within an acceptable range, the short-circuit valve 9 is opened to short-circuit the water filter unit composed of the first filter bottle to the nth filter bottle, and most of the exhaust gas directly reaches the subsequent process through the short-circuit gas path.

[0038] In some embodiments, in the exhaust gas emission system of the boron diffusion equipment, the waste liquid outlet is connected to a waste liquid pipeline, and an acid discharge valve 14 is provided on the waste liquid pipeline. Thus, the discharge of the waste liquid is realized by controlling the opening of the acid discharge valve 14.

[0039] In some embodiments, the exhaust gas emission system of the boron diffusion equipment, in combination Figure 1Looking at it, the first filtration bottle 5 satisfies the following: The first filtration bottle 5 is provided with an inlet for waste gas before primary filtration, an outlet for waste gas after primary filtration, and a waste liquid outlet; among them, the inlet for waste gas before primary filtration is connected to the outlet for cooled waste gas, allowing the cooled waste gas to enter the first filtration bottle for filtration, and the outlet for waste gas after primary filtration is used to discharge the waste gas after primary filtration. Thus, the first filtration bottle 5 uses the above inlets and outlets to connect corresponding pipelines to achieve the functions of primary filtration and waste liquid discharge. Optionally, the inlet for waste gas before primary filtration and the outlet for waste gas after primary filtration are located on the side surface of the first filtration bottle 5, and the waste liquid outlet is located at the bottom of the first filtration bottle 5.

[0040] In some embodiments, in the tail gas emission system of the boron diffusion equipment, combined with Figure 1 Looking at it, when n = 3, the nth filtration bottle satisfies the following: The nth filtration bottle is provided with an inlet for waste gas before the nth stage of filtration, an outlet for waste gas after the nth stage of filtration, and an inlet for compressed air; among them, the inlet for waste gas before the nth stage of filtration allows the waste gas after the (n - 1)th stage of filtration to enter for the nth stage of filtration, and the outlet for waste gas after the nth stage of filtration is used to discharge the waste gas after the nth stage of filtration. Thus, the nth filtration bottle uses the above inlets and outlets to connect corresponding pipelines to achieve the functions of the nth stage of filtration and discharging the waste gas after the nth stage of filtration. Optionally, the inlet for compressed air is located at the top of the nth filtration bottle, and the inlet for waste gas before the nth stage of filtration and the outlet for waste gas after the nth stage of filtration are located on the side surface of the nth filtration bottle.

[0041] Furthermore, in the tail gas emission system of the boron diffusion equipment, the outlet for waste gas after the nth stage of filtration is connected to a diaphragm pump 13, and an evacuation valve 12 is provided on the pipeline between the diaphragm pump 13 and the outlet for waste gas after the nth stage of filtration. Thus, the diaphragm pump 13 provides suction to extract the cooled waste gas, enabling the cooled waste gas to diffuse sequentially from the first filtration bottle to the nth filtration bottle and finally be discharged through the nth filtration bottle; and the presence of the evacuation valve 12 is used to control the on-off between the diaphragm pump 13 and the waste gas after the nth stage of filtration.

[0042] In some embodiments, referring to Figures 1 to 2 , in the tail gas emission system of the boron diffusion equipment, a buffer bottle 3 is further included; the buffer bottle 3 is provided between the cooling bottle 2 and the first filtration bottle 5. Thus, it plays a role of secondary cooling during the air intake process.

[0043] In some embodiments, the filtrate includes water. For example, municipal water supply, various aqueous solutions, etc. are all acceptable.

[0044] In some embodiments, in the tail gas emission system of the boron diffusion equipment, a first filter liquid inlet to an nth filter liquid inlet are respectively provided on the first filter bottle to the nth filter bottle; the first filter liquid inlet to the nth filter liquid inlet are respectively connected with filter liquid pipelines, and a check valve 6 is provided on each filter liquid pipeline. Thus, each filter bottle is filled with liquid separately. Compared with filling a single filter bottle with liquid and then making the liquid enter other filter bottles, the independent filling of the filter bottles can avoid the problem of a sharp increase in system resistance caused by liquid seal during single-bottle filling. The presence of the check valve 6 can prevent the risk of waste gas backwashing through the water path. Optionally, the first filter liquid inlet to the nth filter liquid inlet are all located at the top of the corresponding filter bottle. As an example, refer to Figure 2 , at this time, n is 3, a first filter liquid inlet, a second filter liquid inlet, and a third filter liquid inlet are respectively provided on the first filter bottle 5, the second filter bottle 7, and the third filter bottle 11, the first filter liquid inlet, the second filter liquid inlet, and the third filter liquid inlet are respectively connected with filter liquid pipelines, and a check valve 6 is provided on each filter liquid pipeline.

[0045] In other embodiments, in the tail gas emission system of the boron diffusion equipment, when n≥3, a first filter liquid inlet to an (n - 1)th filter liquid inlet are respectively provided on the first filter bottle to the (n - 1)th filter bottle; the first filter liquid inlet to the (n - 1)th filter liquid inlet are respectively connected with filter liquid pipelines, and a check valve 6 is provided on each pipeline. At this time, the nth filter bottle plays a buffering role, and the waste gas with liquid after being filtered at the (n - 1)th stage enters it, and gas-liquid separation is carried out under the action of gravity, the carried liquid falls into the nth filter bottle, and the waste gas is output through the waste gas outlet after being filtered at the nth stage. As an example, refer to Figure 1 , at this time, n is 3, the first filter bottle 5 and the second filter bottle 7 are filled with liquid separately by filter liquid pipelines, and the presence of the third filter bottle 11 is used to prevent the water in the second filter bottle 7 from being introduced into the diaphragm pump 13 along with a large flow of air during operation, and a part of the liquid will splash into the third filter bottle 11, and gas-liquid separation occurs under the action of gravity.

[0046] The present application will be described below with reference to specific embodiments. It should be noted that these embodiments are merely descriptive and do not limit the present application in any way.

[0047] Embodiment 1

[0048] Refer to Figure 1 As can be seen, Embodiment 1 provides a tail gas emission system of a boron diffusion equipment, at this time, n is 3.

[0049] The tail gas emission system of a boron diffusion device includes: a high-temperature diffusion furnace 1, a cooling bottle 2, a buffer bottle 3, a special gas valve 4, a first filter bottle 5, a check valve 6, a second filter bottle 7, a water valve 8, a short-circuit valve 9, a gas valve 10, a third filter bottle 11, a vacuum valve 12, a diaphragm pump 13, and an acid discharge valve 14; among them, the cooling bottle 2 has an inlet before waste gas cooling and an outlet after waste gas cooling, the buffer bottle 3 has a buffer inlet and a buffer outlet, the first filter bottle 5 has an inlet for waste gas before primary filtration, an outlet for waste gas after primary filtration, a waste liquid outlet, and a first filter liquid inlet, the second filter bottle 7 has an inlet for waste gas before secondary filtration, an outlet for waste gas after secondary filtration, and a second filter liquid inlet, the third filter bottle 11 has an inlet for waste gas before tertiary filtration, an outlet for waste gas after tertiary filtration, and a compressed air inlet; the inlet before waste gas cooling is connected to the high-temperature diffusion furnace 1, the outlet after waste gas cooling is connected to the inlet before waste gas cooling through a pipeline, the outlet after waste gas cooling is connected to the buffer inlet through a pipeline, the buffer outlet is connected to both the inlet for waste gas before primary filtration and a short-circuit gas path through a pipeline, and a special gas valve 4 is provided on the pipeline at the buffer outlet to control the gas flow rate into the inlet for waste gas before primary filtration and the short-circuit gas path by adjusting the opening degree of the valve core thereon; the outlet for waste gas after primary filtration is connected to the inlet for waste gas before secondary filtration through a pipeline, the outlet for waste gas after secondary filtration is connected to the inlet for waste gas before tertiary filtration through a pipeline, the outlet for waste gas after tertiary filtration is connected to the diaphragm pump 13 through a pipeline, and a vacuum valve 12 is provided on the pipeline between the two, and the end of the short-circuit gas path is connected to the pipeline between the outlet for waste gas after tertiary filtration and the vacuum valve 12; the first filter liquid inlet and the second filter liquid inlet are respectively connected to filter liquid pipelines, check valves 6 are provided on both filter liquid pipelines, the two filter liquid pipelines converge on the total filter liquid path, and the water valve 8 is provided on the total filter liquid path; the waste liquid outlet is connected to a waste liquid pipeline, and the acid discharge valve 14 is provided on the waste liquid pipeline; the compressed air inlet is connected to a compressed air pipeline, and a gas valve 10 is provided thereon.

[0050] The working process of the tail gas emission system of this boron diffusion device includes a water addition operation, a tail gas treatment operation, and a drainage operation, which are specifically as follows:

[0051] Water addition operation: Open the water valve 8 and the vacuum valve 12. The water used as the filter liquid enters the connected first filter bottle 5 and second filter bottle 7 respectively through the water valve 8 and the check valve 6 via the filter liquid branch. When the water level reaches the set height, close the water valve 8 and the vacuum valve 12 to complete the water addition.

[0052] Tail gas treatment operation: The high-temperature waste gas is discharged from the high-temperature diffusion furnace 1 and enters the cooling bottle 2; it is preliminarily cooled and sublimated in the cooling bottle 2, and the high-temperature waste gas above 800 °C is preliminarily cooled to below 150 °C. In this operation, part of the boron oxide crystallizes, and the residual uncondensed boron oxide, boron chloride and other waste gases are discharged from the outlet of the cooling bottle 2.

[0053] The cooled waste gas discharged from the outlet of the cooling bottle 2 enters the buffer bottle 3 for secondary cooling. According to whether the waste gas contains harmful substances such as B2O3, BCL3, and Cl2, it is determined whether to take the short-circuit gas path or the water filtration unit. If the contents of B2O3, BCL3, and Cl2 in the waste gas are all within the acceptable range, the short-circuit valve 9 is opened, and the waste gas is directly discharged to the diaphragm pump 13 through the short-circuit gas path. If the content of any one of B2O3, BCL3, and Cl2 in the waste gas is not within its acceptable range, the short-circuit valve 9 remains closed, and the waste gas is discharged to the diaphragm pump 13 after passing through the secondary filtration of the first filter bottle 5 and the second filter bottle 7 in sequence and the gas-liquid separation of the third filter bottle 11. The remaining tail gas reaches the diaphragm pump 13 through the evacuation valve 12 and is then discharged.

[0054] Drainage operation: The air valve 10 and the acid discharge valve 14 are opened. The compressed air first presses the waste liquid in the third filter bottle 9 into the second filter bottle 7 and the first filter bottle 5 in sequence through the connecting pipeline, and then discharges it through the waste liquid pipeline at the bottom of the first filter bottle 5 to complete the acid discharge.

[0055] Example 2

[0056] Others are the same as Example 1, except that the third filter bottle 11 is provided with a third filter liquid inlet, the third filter liquid inlet is connected with a filter liquid branch, one-way valves 6 are provided on all three filter liquid branches, and the three filter liquid branches converge on the filter liquid main road.

[0057] In the description of this specification, the description with reference to terms such as "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0058] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present application. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present application.

Claims

1. An exhaust gas emission system for a boron diffusion device, characterized in that, Comprising: A cooling bottle (2) and a water filtration unit; The cooling bottle (2) is used to cool high-temperature exhaust gas and output the cooled exhaust gas; The water filtration unit is used to provide at least two stages of water filtration for the cooled exhaust gas. The water filtration unit has a liquid inlet pipe and a gas path, and the liquid inlet pipe and the gas path are isolated from each other.

2. The tail gas emission system of the boron diffusion equipment according to claim 1, characterized in that, Comprising: The water filtration unit includes a first filtration bottle to an nth filtration bottle, where n is an integer greater than or equal to 2; The first filtration bottle to the nth filtration bottle are respectively used for the 1st stage filtration to the nth stage filtration of the cooled exhaust gas; The first filtration bottle is further provided with a waste liquid outlet, and the nth filtration bottle is further provided with a compressed air inlet. When compressed air enters the nth filtration bottle through the compressed air inlet, the liquid in the nth filtration bottle to the 2nd filtration bottle can be pressed into the first filtration bottle and discharged through the waste liquid outlet.

3. The tail gas emission system of the boron diffusion equipment according to claim 2, characterized in that It further includes a short-circuit gas path; The short-circuit gas path is connected in parallel with the pipeline where the first filtration bottle to the nth filtration bottle are located, and a short-circuit valve (9) is provided on the short-circuit gas path.

4. The tail gas emission system of the boron diffusion device according to claim 2, characterized in that The first filtration bottle satisfies: The first filtration bottle is provided with a pre-first-stage filtration exhaust gas inlet, a first-stage filtration exhaust gas outlet, and a waste liquid outlet; wherein, the pre-first-stage filtration exhaust gas inlet is communicated with the cooled exhaust gas outlet, allowing the cooled exhaust gas to enter the first filtration bottle for filtration, and the first-stage filtration exhaust gas outlet is used to discharge the first-stage filtered exhaust gas; and / or The nth filtration bottle satisfies: The nth filtration bottle is provided with a pre-nth-stage filtration exhaust gas inlet, an nth-stage filtration exhaust gas outlet, and a compressed air inlet; wherein, the pre-nth-stage filtration exhaust gas inlet allows the (n - 1)th-stage filtered exhaust gas to enter for nth-stage filtration, and the nth-stage filtration exhaust gas outlet is used to discharge the nth-stage filtered exhaust gas.

5. The tail gas emission system of the boron diffusion equipment according to claim 4, characterized in that The nth-stage filtration exhaust gas outlet is connected with a diaphragm pump (13), and a vacuum valve (12) is provided on the pipeline between the diaphragm pump (13) and the nth-stage filtration exhaust gas outlet.

6. The exhaust gas emission system of the boron diffusion equipment according to claim 2, characterized in that, It further includes a buffer bottle (3); The buffer bottle (3) is arranged between the cooling bottle (2) and the first filtration bottle (5).

7. The exhaust gas emission system of the boron diffusion equipment according to claim 5, characterized in that, The waste liquid outlet is connected with a waste liquid pipeline, and an acid discharge valve (14) is provided on the waste liquid pipeline.

8. The tail gas emission system of the boron diffusion equipment according to any one of claims 2 to 7, characterized in that, The first filtration bottle to the nth filtration bottle are respectively provided with a first filtration liquid inlet to an nth filtration liquid inlet; The first filtration liquid inlet to the nth filtration liquid inlet are respectively connected with filtration liquid pipelines, and a one-way valve (6) is provided on each filtration liquid pipeline.

9. The tail gas emission system of the boron diffusion equipment according to any one of claims 2 to 7, characterized in that When n ≥ 3, the first filtration bottle to the (n - 1)th filtration bottle are respectively provided with a first filtration liquid inlet to the (n - 1)th filtration liquid inlet; The first filtration liquid inlet to the (n - 1)th filtration liquid inlet are respectively connected with filtration liquid pipelines, and a one-way valve (6) is provided on each filtration liquid pipeline.

10. The tail gas emission system of the boron diffusion equipment according to any one of claims 2 to 7, characterized in that, The liquid in the nth filtration bottle to the 2nd filtration bottle includes water.

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