CN117619073A

CN117619073A - Waste gas treatment equipment

Info

Publication number: CN117619073A
Application number: CN202311719457.3A
Authority: CN
Inventors: 吴伟力; 顾文豪; 吴叶凡
Original assignee: Zhejiang Yasheng Semiconductor Equipment Co ltd
Current assignee: Zhejiang Yasheng Semiconductor Equipment Co ltd
Priority date: 2023-12-14
Filing date: 2023-12-14
Publication date: 2024-03-01

Abstract

The present invention relates to an exhaust gas treatment device comprising: a cleaning tank for storing cleaning liquid and receiving exhaust gas, the cleaning tank being provided with a first inlet and a first outlet; the input end of the pump is connected with the first outlet of the cleaning box and is used for pumping out the cleaning liquid in the cleaning box; the mixing component is provided with two interfaces at the input end, wherein the first interface is connected with waste gas, the second interface is connected with the output end of the pump, and the output end of the mixing component is connected with the first inlet of the cleaning box; the pump pumps the cleaning liquid into the mixing component and mixes the cleaning liquid with the waste gas entering through the first interface, and the mixed cleaning liquid is discharged into the cleaning box through the first inlet; the output end of the mixing component is provided with a nozzle, and the bottom of the nozzle is positioned below the liquid level in the cleaning box. The invention improves the waste gas cleaning efficiency and reduces the equipment failure rate.

Description

Waste gas treatment equipment

Technical Field

The invention relates to the field of semiconductor waste gas treatment, in particular to waste gas treatment equipment.

Background

The use of a variety of special gases in semiconductor manufacturing processes is required, including process gases: silane, phosphine, arsine, ammonia, boron trichloride, boron trifluoride, chlorine, dichlorosulfonide, silicon tetrachloride, hydrosulfide, sulfur iodide, hydrogen chloride and the like, which are used in different processes of semiconductor manufacture, and the generated waste gas is collected and treated by an exhaust system, and the waste gas is discharged without being well treated, so that atmospheric pollution is caused, the physical health of people is affected, and the waste gas also becomes an important source of gaseous molecular pollutants in semiconductor manufacture.

Currently, for such gas discharge, a treatment method of water washing, adsorption, incineration, or a combination of both is generally adopted. The scrubber is an apparatus for treating halogen-series water-soluble gases such as hydrogen chloride, chlorine, boron trichloride, and hydrogen fluoride. However, the existing treatment equipment only discharges the waste gas into water, and the dissolution efficiency is not high. And because insoluble solid particles are mixed in the waste gas and the insoluble solid particles generated by the reaction of the waste gas and water exist in the waste water, the unsaturated waste water is difficult to recycle. The existing treatment equipment needs to be filled with the filter core when recycling the wastewater so as to filter out particulate matters, and the filter core needs to be cleaned and replaced regularly, so that the use is inconvenient.

Therefore, the invention of the treatment equipment with high treatment efficiency and high wastewater recycling rate is urgently needed.

Disclosure of Invention

In order to improve the treatment efficiency of the waste gas and reduce the consumption of cleaning liquid for cleaning the waste gas, the invention provides waste gas treatment equipment, which comprises:

a cleaning tank for storing cleaning liquid and receiving exhaust gas, the cleaning tank being provided with a first inlet and a first outlet;

the input end of the pump is connected with the first outlet of the cleaning box and is used for pumping out the cleaning liquid in the cleaning box;

the mixing component is provided with two interfaces at the input end, wherein the first interface is connected with waste gas, the second interface is connected with the output end of the pump, and the output end of the mixing component is connected with the first inlet of the cleaning box; the pump pumps the cleaning liquid into the mixing component and mixes the cleaning liquid with the waste gas entering through the first interface, and the mixed cleaning liquid is discharged into the cleaning box through the first inlet;

the output end of the mixing component is provided with a nozzle, the bottom of the nozzle is positioned below the liquid level in the cleaning box, and the nozzle is used for discharging the cleaning liquid mixed with the waste gas below the liquid level in the cleaning box and forming foam cleaning liquid.

Preferably, a partition plate is vertically arranged in the cleaning box, a communication port is formed in the top of the partition plate, the partition plate divides the interior of the cleaning box into a first sub-box and a second sub-box, and the first sub-box and the second sub-box are communicated through the communication port in the top of the partition plate;

the first outlet is arranged at the bottom of the first sub-tank;

the nozzle of the mixing component is arranged above the second sub-tank, so that the cleaning liquid discharged by the nozzle enters the position below the liquid level in the second sub-tank, and when the height of the cleaning liquid in the second sub-tank is larger than that of the communicating opening, the cleaning liquid in the second sub-tank can enter the first sub-tank through the communicating opening.

Preferably, the side wall of the first sub-tank is provided with a liquid level meter, the output end of the pump is further connected with a liquid discharge pipe, when the reading of the liquid level meter is larger than a first preset value, a pipeline between the pump and the mixing component is closed, a pipeline between the pump and the liquid discharge pipe is opened, and the cleaning liquid mixed with waste gas in the first sub-tank is pumped into the liquid discharge pipe through the first outlet.

Preferably, the side wall of the first sub-tank is provided with a second inlet, the second inlet is connected with a cleaning liquid supply device, and cleaning liquid can be injected into the first sub-tank through the second inlet.

Preferably, when the cleaning solution supplying apparatus injects the cleaning solution into the cleaning tank, the injection of the cleaning solution into the first sub-tank through the second inlet is stopped when the reading of the level gauge reaches a second preset value, and the second preset value is smaller than the first preset value.

Preferably, when the reading of the level gauge is lower than a third preset value, the discharge of the cleaning liquid in the cleaning tank into the liquid discharge pipe is stopped, and the third preset value is smaller than the second preset value.

Preferably, an exhaust port is arranged at the top of the cleaning box and is used for exhausting the gas cleaned by the cleaning liquid.

Preferably, the exhaust port is connected with the water-gas separation device and the acid drain pipe assembly in sequence.

Preferably, the washing machine further comprises a cabinet body for accommodating the washing box, the pump, the mixing component, the water-gas separation device, the acid discharge pipe assembly and a pipeline connected with the pump, wherein an exhaust assembly is arranged at the top of the cabinet body and is connected with the acid discharge pipe assembly for discharging the gas washed by the washing liquid to the outside.

Preferably, the exhaust gas contains a carrier gas, the flow rate of the carrier gas is 10 to 100 times that of the exhaust gas, and the carrier gas enters the mixing component after being mixed with the exhaust gas through the first interface; the carrier gas is also connected with the acid discharge pipe assembly and is discharged after being mixed with the cleaned gas.

Preferably, the carrier gas is nitrogen and the cleaning fluid is water.

The invention has the following beneficial effects:

1. the tank body is divided into two parts, so that sediment entering the pump is reduced, and the recycling rate of the cleaning liquid is improved;

2. the mixing component can generate a large amount of foam-shaped cleaning liquid, so that the waste gas cleaning efficiency is improved;

3. the nitrogen is used as carrier gas, so that the deposition of particles in a pipeline is reduced, the failure rate of equipment is reduced, the foam quantity is increased, and the waste gas cleaning efficiency is further improved.

Drawings

FIGS. 1 and 2 are block diagrams of the exhaust gas treatment device of the present invention used in parallel;

fig. 3 is a block diagram of the exhaust gas treatment apparatus of the present invention disposed in parallel to a cabinet.

Detailed Description

An exhaust gas treatment device according to the present invention will be described in further detail with reference to the accompanying drawings and detailed description. The advantages and features of the present invention will become more apparent from the following description. It should be noted that the drawings are in a very simplified form and are all to a non-precise scale, merely for the purpose of facilitating and clearly aiding in the description of embodiments of the invention. For a better understanding of the invention with objects, features and advantages, refer to the drawings. It should be understood that the structures, proportions, sizes, etc. shown in the drawings are for illustration purposes only and should not be construed as limiting the invention to the extent that any modifications, changes in the proportions, or adjustments of the sizes of structures, proportions, or otherwise, used in the practice of the invention, are included in the spirit and scope of the invention which is otherwise, without departing from the spirit or essential characteristics thereof.

Referring to fig. 1 to 3, an exhaust gas treatment apparatus according to the present invention includes: a purge tank 1, a pump 4 and a mixing member 5. The purge bin 1 is for storing a purge liquid and for receiving an exhaust gas, the exhaust gas being purged with the purge liquid, the purge bin 1 being provided with a first inlet 2 and a first outlet 3. The input end of the pump 4 is connected with the first outlet 3 of the cleaning tank and is used for pumping out the cleaning liquid in the cleaning tank. The output end of the mixing component 5 is connected with the first inlet 2 of the cleaning tank 1, specifically, the output end of the mixing component 5 is inserted into the first inlet 2 of the cleaning tank 1 and extends into the cleaning tank 1, the mixing component 5 positioned outside the cleaning tank 1 is an input end, a connecting flange is arranged on the mixing component 5, and the mixing component 5 is fixedly connected with the outer side wall of the cleaning tank 1 through the cooperation of the connecting flange and a bolt; the input end of the mixing component 5 is provided with two interfaces, wherein the first interface 6 is connected with waste gas, the second interface 7 is connected with the output end of the pump 4, and the waste gas and a pipeline connected with the pump 4 can be fixedly connected through a flange. The pump 4 can pump the cleaning liquid in the cleaning tank 1 out through the first outlet 3 and into the mixing element 5 through the second port 7. The exhaust gases are then discharged into the mixing element 5 via the first connection 6 and mixed with the cleaning liquid pumped into the mixing element 5, in which they undergo a first-stage dissolution and/or chemical reaction with the cleaning liquid. The output end of the mixing member 5 is provided with a nozzle 8, the bottom of which nozzle 8 extends below the liquid level in the washing tank 1 for discharging the washing liquid mixed with the exhaust gases below the liquid level in the washing tank 1 and for performing a second stage of dissolution and/or chemical reaction with the washing liquid in the washing tank 1. In the second stage, the cleaning solution in the cleaning tank 1 contacts the exhaust gas to form foam. The foam-shaped cleaning liquid can increase the contact area with the waste gas, so that the treatment efficiency of the waste gas is increased, and the water-soluble waste gas can be more quickly fused into the cleaning liquid, or the reaction efficiency of part of the waste gas and the cleaning liquid is improved. Therefore, the foam-shaped cleaning liquid enhances the cleaning effect of the exhaust gas by increasing the contact area with the exhaust gas. The foam-like cleaning liquid entering the cleaning tank 1 slowly releases the gas insoluble in the cleaning liquid, and after the release of the gas, the foam-like cleaning liquid gradually disappears to form a liquid solution. Before these solutions become saturated solutions, they can also be pumped by the pump 4 through the first outlet 3 and re-enter the mixing element 5 through the second port 7 for recycling. Wherein solid particles in the cleaning liquid are deposited to the bottom of the cleaning tank.

In order to separate the particles and reduce the suction of the particles by the pump 4 when pumping out the cleaning liquid, a partition plate 13 is vertically arranged in the cleaning tank 1, and a communication port 14 is arranged at the top of the partition plate 13. The partition 13 divides the interior of the washing tank 1 into a first sub-tank 11 and a second sub-tank 12, and the first sub-tank 11 and the second sub-tank 12 are communicated through a communication port 14 at the top of the partition 13. The height of the partition 13 in this case is lower than the height of the washing tank 1, and the top of the partition 13 and the top area of the washing tank 1 form the communication port 14. The first outlet 3 is disposed at the bottom of the first sub-tank 11, the nozzle 8 of the mixing member 5 is disposed above the second sub-tank 12, and the cleaning liquid discharged from the nozzle 8 can enter below the liquid level of the cleaning liquid in the second sub-tank 12. When the liquid level of the cleaning liquid in the second sub-tank 12 exceeds the height of the communication port 14 after a large amount of gas is dissolved in the cleaning liquid in the second sub-tank 12, the cleaning liquid in the second sub-tank 12 can enter the first sub-tank 11 through the communication port 14, and here, a part of the foam-like cleaning liquid above the cleaning liquid in the second sub-tank 12 is also included and enters the first sub-tank 11 through the communication port. The partition 13 has an isolating effect, the second sub-tank 12 is mainly used for depositing particulate matters, and the first sub-tank 11 is used for providing circulating cleaning liquid. The cleaning solution on the upper layer of the second sub-tank 12 contains less particulate matters, when the liquid level of the cleaning solution in the second sub-tank 12 is higher than the communication port 14, the cleaning solution in the second sub-tank 12 can pass through the partition plate 13 to enter the first sub-tank 11, and then the entering cleaning solution containing less particulate matters is sucked into the mixing component 5 by the pump 4 to participate in recycling, so that the utilization rate of the cleaning solution is improved.

Further, a liquid level meter 15 is disposed on a side wall of the first sub-tank 11, and is used for monitoring the content of the cleaning solution in the first sub-tank 11, the output end of the pump 4 is further connected with a liquid discharge pipe 16, when the reading of the liquid level meter 15 is greater than a first preset value (also referred to as the highest liquid level), a pipeline between the pump 4 and the mixing component 5 is closed, a pipeline between the pump 4 and the liquid discharge pipe 16 is opened, and the cleaning solution mixed with the waste gas in the first sub-tank 11 is pumped into the liquid discharge pipe 16 through the first outlet 3, and is conveyed to a waste liquid pool by the liquid discharge pipe 16. Wherein the opening and closing of the pipeline can be realized by arranging a valve on the pipeline.

Further, the side wall of the first sub tank 11 is provided with a second inlet 17, which is connected to a cleaning liquid supply device, and cleaning liquid can be injected into the first sub tank 11 through the second inlet 17. The second inlet 17 may be connected to a pipe extending above the washing tank 1 to facilitate the injection of washing liquid. In using the exhaust gas treatment device of the present invention, it is necessary to add a certain amount of cleaning liquid in the cleaning tank 1 in advance, that is, the cleaning liquid supply device adds a certain amount of cleaning liquid to the first sub-tank 11 through the second inlet 17. When the reading of the level gauge 15 is a second preset value (also referred to as the working level), which is smaller than the first preset value, the injection of the cleaning liquid into the first sub-tank 11 is stopped. When the height of the cleaning liquid reaches the working liquid level, a round of cyclic use can be started until the liquid level is saturated to be increased to the highest liquid level, and liquid discharge is started. In this example, when the cleaning solution reaches the maximum level, it means that a large amount of exhaust gas is dissolved in the cleaning solution, and the cleaning solution is close to the saturated solution at this time, and is not suitable for recycling. At this time, the cleaning liquid in the cleaning tank 1 needs to be discharged, and the cleaning liquid in the first sub-tank 11 needs to be pumped out by the pump 4. A third preset value (also called minimum level) may be set when discharging saturated cleaning solution, and when the reading of the level meter 15 is lower than the third preset value, the liquid discharge may be stopped, and the third preset value is smaller than the second preset value.

Further, a second outlet 19 may be further disposed at the bottom of the second sub-tank 12, the second outlet 19 is connected to the input end of the pump 4, a valve is disposed on a pipeline between the pump 4 and the second outlet 19, and when necessary, the valve between the pump 4 and the second outlet 19 is opened to pump the cleaning solution in the second sub-tank 12 out through the second outlet 19, and the cleaning solution is discharged into the drain pipe 16 by the pump 4. When the saturated cleaning liquid is discharged to make the liquid level reach the third preset value, the liquid discharge can be stopped, and the new cleaning liquid can be injected into the first sub-tank 11 through the second inlet 17 by adopting the cleaning liquid supply device until the cleaning liquid level of the first sub-tank 11 reaches the working liquid level.

In a preferred embodiment, as shown in fig. 3, the exhaust gas treatment device further comprises a tank 9 for accommodating and mounting the purge tank 1, the pump 4, the mixing member 5, and a pipe connected to the pump 4. The cabinet body 9 can also be arranged to be used for accommodating a plurality of cleaning boxes 1, a plurality of pumps 4, a plurality of mixing components 5 and pipelines connected with a plurality of pumps 4, namely, integrated equipment for integrating a plurality of cleaning boxes 1 into parallel for use can be integrated through one cabinet body 9, and waste gas is simultaneously connected into the plurality of cleaning boxes 1 for cleaning respectively, so that waste gas cleaning efficiency is quickened.

Further, an exhaust port 18 is provided at the top of the cleaning tank 1, and the exhaust port 18 is used for exhausting the gas cleaned by the cleaning liquid. The exhaust gas mentioned in this example mainly refers to the gas generated during the semiconductor etching, deposition, epitaxy and the like, and the cleaning liquid is water. These gases are often corrosive and toxic and typically require dilution with a carrier gas, which may be nitrogen or other inert gas, before being introduced into the purge bin. The flow of the carrier gas is 10 to 100 times of the flow of the waste gas in general, and the large-flow carrier gas can enable particles in the waste gas to smoothly enter the cleaning box 1, so that the smoothness of a pipeline in the process of entering the cleaning box 1 is ensured. In this embodiment, nitrogen is used as the carrier gas, preferably, the flow rate of the exhaust gas is 800sccm, and 60slm of nitrogen may be used to pass through the mixing component 5 together with 800sccm of exhaust gas. In this example, the nitrogen gas not only serves to dilute the exhaust gas, but also increases the flow rate of the exhaust gas when it is introduced, so that more bubble-like cleaning liquid is generated after passing through the mixing member 5. Therefore, the nitrogen acts to dilute the exhaust gas, reducing the corrosion rate of the purge bin 1 and the side walls of the pipe passing by; the large flow of nitrogen generates more bubble-shaped cleaning liquid, so that the contact area of waste gas and the cleaning liquid is quickened, and the cleaning efficiency is improved; furthermore, the high-flow atmosphere can clean the pipeline through which the waste gas passes, so that the deposition of particulate matters in the pipeline is reduced.

Further, the second exhaust port 18 is sequentially connected to the water-gas separator 21 and the acid pipe assembly 22. The cleaned gas is dried by the water-gas separation device 21 in sequence, and then the acid gas is further removed by the acid pipe assembly 22 and is discharged to the atmosphere. Alternatively, in the cabinet body with a plurality of cleaning tanks 1 connected in parallel, the cabinet body 9 can also accommodate a plurality of water-gas separation devices 21 and acid-discharge pipe assemblies 22, and the gas treated by the acid-discharge pipe assemblies 22 is intensively discharged to the atmosphere through an exhaust assembly 23 arranged at the top of the cabinet body 9.

The invention has the following beneficial effects:

It is noted that relational terms such as first and second, and the like are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Moreover, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one … …" does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises the element.

In the description of the present invention, unless explicitly stated and limited otherwise, the terms "mounted," "connected," and "secured" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communicated with the inside of two elements or the interaction relationship of the two elements. The specific meaning of the above terms in the present invention will be understood in specific cases by those of ordinary skill in the art.

In the present invention, unless expressly stated or limited otherwise, a first feature "above" or "below" a second feature may include both the first and second features being in direct contact, as well as the first and second features not being in direct contact but being in contact with each other through additional features therebetween. Moreover, a first feature being "above," "over" and "on" a second feature includes the first feature being directly above and obliquely above the second feature, or simply indicating that the first feature is higher in level than the second feature. The first feature being "under", "below" and "beneath" the second feature includes the first feature being directly under and obliquely below the second feature, or simply means that the first feature is less level than the second feature.

While the present invention has been described in detail through the foregoing description of the preferred embodiment, it should be understood that the foregoing description is not to be considered as limiting the invention. Many modifications and substitutions of the present invention will become apparent to those of ordinary skill in the art upon reading the foregoing. Accordingly, the scope of the invention should be limited only by the attached claims.

Claims

1. An exhaust gas treatment device, comprising:

a cleaning tank (1) for storing cleaning liquid and receiving exhaust gas, on which a first inlet (2) and a first outlet (3) are provided;

the input end of the pump (4) is connected with the first outlet (3) of the cleaning box (1) and is used for pumping out the cleaning liquid in the cleaning box;

the mixing component (5) is provided with two interfaces at the input end, wherein the first interface (6) is connected with waste gas, the second interface (7) is connected with the output end of the pump (4), and the output end of the mixing component is connected with the first inlet (2) of the cleaning box (1); the pump (4) pumps the cleaning liquid into the mixing component (5) and mixes the cleaning liquid with the waste gas entering through the first interface (6), and the mixed cleaning liquid is discharged into the cleaning tank (1) through the first inlet (2);

a nozzle (8) is arranged at the output end of the mixing component (5), and the bottom of the nozzle (8) is positioned below the liquid level in the cleaning box (1).

2. The exhaust gas treatment device according to claim 1, wherein a partition plate (13) is vertically arranged in the purge bin (1), a communication port (14) is formed in the top of the partition plate (13), the partition plate (13) divides the interior of the purge bin (1) into a first sub-bin (11) and a second sub-bin (12), and the first sub-bin (11) and the second sub-bin (12) are communicated through the communication port (14) in the top of the partition plate (13);

the first outlet (3) is arranged at the bottom of the first sub-tank (11);

the nozzle (8) of the mixing component (5) is arranged above the second sub-tank (12), and the cleaning liquid discharged by the nozzle (8) can enter the position below the liquid level in the second sub-tank (12), and when the height of the cleaning liquid in the second sub-tank (12) exceeds the height of the communication port (14), the cleaning liquid in the second sub-tank (12) can enter the first sub-tank (11) through the communication port (14).

3. An exhaust gas treatment device according to claim 2, characterized in that the side wall of the first sub-tank (11) is provided with a level gauge (15), the output end of the pump (4) is further connected with a drain pipe (16), that when the reading of the level gauge (15) is larger than a first preset value, the pipe between the pump (4) and the mixing member (5) is closed, the pipe between the pump (4) and the drain pipe (16) is opened, and that the cleaning liquid mixed with exhaust gas in the first sub-tank (11) is pumped into the drain pipe (16) through the first outlet (3).

4. An exhaust gas treatment device according to claim 3, characterized in that the side wall of the first sub-tank (11) is provided with a second inlet (17), said second inlet (17) being connected to a cleaning liquid supply device, whereby cleaning liquid can be injected into the first sub-tank (11) through the second inlet (17).

5. An exhaust gas treatment device according to claim 4, characterized in that the injection of cleaning liquid into the first sub-tank (11) through the second inlet (17) is stopped when the reading of the level gauge (15) reaches a second preset value, which is smaller than the first preset value.

6. An exhaust gas treatment device according to claim 5, characterized in that the discharge of cleaning liquid in the cleaning tank (1) into the liquid discharge pipe (16) is stopped when the reading of the liquid level meter (15) is below a third preset value, which is smaller than the second preset value.

7. An exhaust gas treatment device according to any one of claims 1-6, characterized in that the top of the washing tank (1) is provided with an exhaust port (18) for exhausting the gas after washing by the washing liquid.

8. The exhaust gas treatment device according to claim 7, characterized in that the exhaust port (18) is connected in sequence to a water-gas separation means (21) and an acid stack assembly (22).

9. The exhaust gas treatment apparatus according to claim 8, further comprising a tank body (9) for accommodating the purge tank (1), the pump (4), the mixing member (5), the water-gas separation device (21), the acid drain pipe assembly (22), and a pipe connected to the pump (4), wherein an exhaust gas assembly (23) is provided at a top of the tank body (9), and the exhaust gas assembly (23) is connected to the acid drain pipe assembly (22) for discharging the gas purged by the purge liquid to the outside.

10. The exhaust gas treatment device according to claim 7, characterized in that the exhaust gas comprises a carrier gas, the flow of which is 10 to 100 times the flow of exhaust gas, which carrier gas enters the mixing member (5) after mixing with the exhaust gas via the first interface (6); the carrier gas is also coupled to the acid conduit assembly (22) and is mixed with the cleaned gas.