Plasma tail gas treatment equipment

Abstract

The utility model discloses plasma tail gas treatment equipment which comprises a tail gas treatment unit, a gas inlet unit, a cooling unit and a washing adsorption unit, the tail gas treatment unit comprises a plasma generator and a plasma reaction assembly, and the plasma reaction assembly forms a reaction cavity. The reaction cavity is also communicated with an external pipeline for supplying oxygen or air; the air inlet unit comprises a plurality of air inlet pipelines arranged in the circumferential direction. The cooling unit forms a cooling cavity, and the cooling cavity is upwards communicated with the reaction cavity; and the washing adsorption unit comprises a scrubber tower, a gas inlet of the scrubber tower is communicated with the tail end of the Z-shaped channel, the scrubber tower carries out washing adsorption on the flowing tail gas, and the scrubber tower is provided with an exhaust port communicated with the outside. The tail gas treatment device is reasonable in structure, good in tail gas treatment effect and beneficial to structure simplification and size miniaturization.

Description

TECHNICAL FIELD

[0001] The utility model relates to semiconductor tail gas processing technical field, concretely is a kind of plasma tail gas processing equipment. BACKGROUND

[0002] In the semiconductor manufacturing process, especially in chemical vapor deposition (CVD), etching and other processes involving gas reaction, a variety of harmful tail gas can be produced. These tail gas may contain volatile organic compounds (VOCs), fluorides, chlorides, acidic gases and other toxic or corrosive substances. Plasma technology is a method for treating semiconductor tail gas, which uses high temperature plasma to decompose harmful gas components. The plasma generator is a non-transferred arc DC plasma torch, which uses nitrogen or oxygen as the plasma working gas, and generates a hot plasma jet with a temperature of up to 16000°C through arc discharge. The pyrolysis reaction chamber is heated to a high temperature under this high temperature, and the industrial waste gas to be treated is decomposed into atoms or dissociated into charged particles, and there are a large number of ions, free radicals and active molecules, which can rapidly thermally decompose or oxidize the industrial waste gas, and become harmless products or easily treated substances.

[0003] The plasma tail gas treatment equipment still has a high temperature after thermal decomposition or oxidation, and needs to be cooled and then water-washed and adsorbed before being discharged. In the prior art, spraying water is often used for cooling, and the cooling effect of spraying water is often limited. Moreover, the flow rate of the tail gas is still relatively fast before entering the water-washing and adsorption scrubber, and the cooling effect is insufficient. Therefore, the burden on the scrubber is increased, and the scrubber often needs to continue cooling. Therefore, a water vapor separation unit needs to be additionally provided in the scrubber to discharge the tail gas outside. Therefore, not only the manufacturing cost is high, but also the volume miniaturization is not conducive. UTILITY MODEL CONTENT

[0004] The utility model discloses a kind of plasma tail gas treatment equipment, it solves the technical problem that tail gas treatment equipment structure complex, manufacturing cost is high and not conducive to volume miniaturization in prior art, with structure reasonable, tail gas treatment effect is good, it is favorable to the technical effect of simplifying structure volume miniaturization. The technical scheme as follows is used:

[0005] A kind of plasma tail gas treatment equipment, comprising:

[0006] Tail gas treatment unit, including plasma generator and plasma reaction component, the hot plasma jet generated by the plasma generator enters the reaction cavity formed by plasma reaction component, and the tail gas in it is purified and handled, the reaction cavity is also connected with the external pipeline of oxygen or air supply;

[0007] The air inlet unit comprises a plurality of air inlet pipes arranged in a circumferential direction, and air outlets of the air inlet pipes are arranged at an upper portion of the reaction chamber, so that the tail gas can enter the reaction chamber through the air inlet pipes;

[0008] The cooling unit forms a cooling chamber, which is communicated with the reaction chamber upwardly, and a plurality of baffle plates facing the reaction chamber are fixed in the cooling chamber, the baffle plates form a Z-shaped channel, and the cooling chamber is respectively communicated with a water inlet and a water outlet, cooling water supplied by the water inlet is discharged through the water outlet along the Z-shaped channel downwardly;

[0009] The water washing and adsorption unit comprises a gas scrubbing tower, an air inlet of the gas scrubbing tower is communicated with an end of the Z-shaped channel, the gas scrubbing tower performs water washing and adsorption on the tail gas flowing therethrough, and the gas scrubbing tower is provided with an air outlet communicated with the outside.

[0010] On the basis of the above technical scheme, a plurality of baffle plates are fixed on opposite two side walls of the cooling chamber, and the baffle plates have an angle inclined downwardly from outside to inside.

[0011] On the basis of the above technical scheme, an end of the Z-shaped channel is communicated with the air inlet of the gas scrubbing tower through a rectifying channel, the rectifying channel comprises a plurality of rectifying branches arranged side by side, two adjacent rectifying branches are connected in a head-to-tail manner, and a drainage outlet is arranged below an end of the rectifying channel.

[0012] On the basis of the above technical scheme, the rectifying channel is arranged side by side with the cooling chamber and formed in a liquid storage tank, and the tail gas treatment unit and the water washing and adsorption unit are arranged side by side on the liquid storage tank.

[0013] On the basis of the above technical scheme, a gas passing chamber is further arranged, the gas passing chamber is open upwardly and communicated with the gas scrubbing tower, and an end of the rectifying channel is communicated with the gas passing chamber through a plurality of gas passing pipelines to buffer the tail gas flow.

[0014] On the basis of the above technical scheme, a gas passing outlet of the gas passing pipeline communicated with the gas passing chamber is arranged on a side wall of the gas passing chamber and communicated with the gas passing chamber horizontally.

[0015] On the basis of the above technical scheme, at least one filler layer and at least one spraying assembly are arranged in the gas scrubbing tower, the spraying assembly comprises a plurality of spraying heads, spraying liquid sprayed by the spraying heads is used for spraying and cooling the tail gas, and the filler layer comprises a plurality of stacked fillers, the fillers enable the tail gas to be in contact with the spraying liquid sufficiently.

[0016] On the basis of the above technical scheme, the reaction chamber is conical with a large upper portion and a small lower portion, a surrounding chamber abutting an outer wall of the reaction chamber is formed outside the reaction chamber, the surrounding chamber is communicated with the reaction chamber through a plurality of through holes, and the surrounding chamber is communicated with an external pipeline to enable oxygen or air to enter the reaction chamber.

[0017] On the basis of the above technical solutions, the surrounding cavity is externally provided with a heat preservation layer.

[0018] On the basis of the above technical solutions, the heat preservation layer is externally provided with a water cooling cavity, and the water cooling cavity is respectively communicated with a lower water inlet and an upper water outlet.

[0019] Beneficial effects

[0020] The utility model discloses a reasonable structure, and the cooling cavity formed by the cooling and temperature reducing unit is communicated with the reaction cavity upwards, when the high-temperature tail gas after reaction enters the cooling cavity downwards, on the one hand, the tail gas directly impacts the cooling water, improves the cooling and temperature reducing effect, on the other hand, the baffle is arranged to the gas outlet of the reaction cavity, can effectively buffer the high-temperature tail gas, further improves the cooling and temperature reducing effect, in addition, the Z-shaped channel is formed in the cooling cavity, so that the diffusion time of the tail gas in the cooling cavity is greatly extended in the limited space, not only further buffers the tail gas, but also makes the tail gas fully contact with the cooling water, improves the cooling effect, and performs partial degree water washing and adsorption.

[0021] In the utility model, the cooling cavity and the rectifying channel are arranged side by side and form the liquid storage cavity, the cooling cavity can be communicated with the lower part of the rectifying channel, so that the flow rate of the tail gas is further reduced after multiple collisions in the rectifying channel, and the large particle liquid beads in the tail gas fall, and the rectifying channel plays the effect of gas-liquid separation.

[0022] In the utility model, the tail gas entering the gas washing tower is evenly diffused in the gas washing tower through the air passing cavity and the air passing pipeline, which is beneficial to the full contact between the tail gas and the filler, further improves the water washing and adsorption effect, and is beneficial to improving the tail gas treatment effect.

[0023] In the utility model, the reaction cavity is conical from top to bottom, so that a certain pressure difference is formed in the lower part of the reaction cavity, the high-temperature tail gas is discharged from the reaction cavity more quickly, and the reaction efficiency is improved. ACCURATE DRAWINGS

[0024] In order to more clearly illustrate the technical scheme in the embodiments of the utility model or the prior art, the following will briefly introduce the drawings needed to be used in the embodiment or the prior art description. Obviously, the drawings in the following description are only one embodiment of the utility model, and for those skilled in the art, other embodiment drawings can be obtained according to the provided drawings without creating creative labor.

[0025] Figure 1 The utility model discloses a three-dimensional structure schematic diagram;

[0026] Figure 2 The utility model discloses the sectional structure schematic diagram of front view;

[0027] Figure 3 : Figure 2 Partial enlarged structural schematic view at A-A in FIG. 1; DETAILED DESCRIPTION

[0028] The following description and drawings are illustrative of the specific embodiments herein and are not intended to be limiting. Parts and features of some embodiments can be included in or substituted for parts and features of other embodiments. The scope of the embodiments herein encompasses the entire scope of the claims and all available equivalents thereof. In the description herein, the terms "first," "second," etc. are used merely as labels to facilitate discussion and are in no way intended to limit the scope of the application. Indeed, first and second elements can both be considered a first element according to some embodiments. Furthermore, the terms "comprises", "comprising", or any other variation thereof are intended to cover a non-exclusive inclusion, such that a structure, device or apparatus that comprises a list of elements is not necessarily limited to only those elements but can include other elements not expressly listed or inherent to such structure, device or apparatus. An element proceeded by "comprises... a" does not, without more constraints, exclude the existence of additional identical elements in the structure, device or apparatus that includes the element. Various embodiments are described herein with reference to a progressive manner. Each of the embodiments highlights differences from other embodiments, and the same or similar parts between the embodiments can be mutually referred to.

[0029] The terms "longitudinal", "lateral", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like, as used herein, refer to the orientation or position shown in the drawings, and are merely used for convenience and in the interest of brevity in describing the embodiments herein and simplifying the present disclosure, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore should not be construed as limiting the application. In the description of the embodiments herein, unless otherwise specified and limited, the terms "mount", "connected", "connection" should be interpreted broadly, for example, can be mechanical or electrical connection, can be internal connection of two elements, can be direct connection, or indirect connection through intermediate medium, and the specific meaning of the above terms can be understood by the person skilled in the art according to the specific circumstances.

[0030] In the present disclosure, the term "a plurality of" means two or more, unless otherwise specified.

[0031] In the present disclosure, the character " / " represents an "or" relationship between the objects before and after it. For example, A / B means A or B.

[0032] In this article, the term "and / or" describes an association between objects, indicating that three relationships can exist. For example, A and / or B means: A or B, or A and B.

[0033] like Figures 1-3 The exhaust gas treatment unit shown includes a plasma generator 1 and a plasma reaction assembly 2. The plasma generator 1 is existing technology and will not be described in detail here. Those skilled in the art can select it according to their needs.

[0034] The plasma reaction assembly 2 has a reaction chamber 21 located in the center. The hot plasma jet generated by the plasma generator 1 enters the reaction chamber 21 formed by the plasma reaction assembly 2 and then purifies the exhaust gas therein.

[0035] like Figure 2 and 3 As shown, the reaction chamber 21 is conical, wider at the top and narrower at the bottom. A surrounding cavity 22, conforming to the outer wall of the reaction chamber 21, is formed around it. The surrounding cavity 22 communicates with the reaction chamber 21 through several through holes and is also connected to external pipelines, allowing oxygen or air to enter the reaction chamber 21 via the surrounding cavity. The arrangement of the surrounding cavity 22 creates a "gas film" on the outer layer of the reaction chamber 21, ensuring sufficient contact between the exhaust gas and oxygen or air, thus increasing the degree of high-temperature pyrolysis reaction. Appropriate supplementation of oxygen or air can aid combustion of the exhaust gas in the reaction chamber and improve pyrolysis conversion efficiency. Furthermore, it can self-purge the inner wall of the reaction chamber 21, preventing the adhesion of solid powder.

[0036] In this embodiment, a heat insulation layer 23 is provided outside the surrounding cavity 22. In this application, the heat insulation material used for the heat insulation layer 23 is the prior art. Those skilled in the art can select it according to their needs. The setting of the heat insulation material reduces the heat exchange between the inside and outside of the reaction cavity 21, which is conducive to maintaining a high temperature and stable environment inside the reaction cavity 21, thereby improving the degree of tail gas pyrolysis reaction.

[0037] The insulation layer 23 is provided with a water-cooling cavity 24. The water-cooling cavity 24 is annular and is connected to the lower water inlet and the upper water outlet, thus avoiding safety accidents caused by accidental contact.

[0038] In addition, the reaction chamber 21 is cone-shaped with a larger top and a smaller bottom, which creates a certain pressure difference in the lower part of the reaction chamber 21, allowing the high-temperature exhaust gas to be discharged from the reaction chamber 21 more quickly, which is beneficial to improving the reaction efficiency.

[0039] The intake unit includes several circumferentially arranged intake pipes 7. The outlet of the intake pipe 7 is located at the upper part of the reaction chamber 21, and the exhaust gas can enter the reaction chamber 21 through the intake pipes 7. Figure 2 As shown, the outlet of the air inlet pipe 7 has an angle toward the central axis of the reaction chamber 21;

[0040] The hot plasma jet generated by the plasma generator 1 heats the reaction cavity 21, and the reaction cavity 21 absorbs heat energy to form an integrated reaction energy source, so as to promote the high-temperature cracking of the tail gas. In this embodiment, the plasma generator 1 is a non-transferred arc DC plasma torch, nitrogen or oxygen is used as the plasma working gas, and an electric arc discharge is used to generate a hot plasma jet with a temperature of up to 16000 DEG C. At a high temperature, the tail gas to be treated in the reaction cavity 21 is decomposed into atoms or ionized into charged particles, and a large number of ions, free radicals and active molecules exist, which can rapidly thermally decompose or oxidize various harmful components in the tail gas, and change them into harmless products or easily treated substances.

[0041] A liquid storage cavity 100 is arranged below the plasma reaction assembly 2, and a cooling and temperature reduction unit and a rectifying passage 33 are arranged side by side in the liquid storage cavity 100.

[0042] As shown in Figure 2 , the cooling and temperature reduction unit forms a temperature reduction cavity, the temperature reduction cavity is communicated with the reaction cavity 21 upwardly, and a plurality of baffle plates 31 facing the reaction cavity are fixedly arranged in the temperature reduction cavity. The plurality of baffle plates 31 form a Z-shaped channel 32, and the temperature reduction cavity is respectively communicated with a water inlet 35 and a water outlet. The cooling water supplied by the water inlet 35 flows downwardly along the Z-shaped channel 32 and is discharged through the water outlet.

[0043] As shown in Figure 2 , the plurality of baffle plates 31 are fixedly arranged on the opposite two side walls of the temperature reduction cavity, and the baffle plates 31 have an angle downwardly inclined from outside to inside, so as to guide the cooling water to flow downwardly under the action of gravity. The two baffle plates 31 arranged side by side and upwardly and downwardly, the end of the upper baffle plate 31 extends outwardly and partially shields the lower baffle plate 31. In this way, when the cooling water flows downwardly from the upper baffle plate 31, a water curtain is formed, and the tail gas diffuses in the Z-shaped channel 32 through the water curtain. In this way, not only the tail gas flow can be further buffered, but also the cooling and temperature reduction effect is greatly improved.

[0044] The end of the Z-shaped channel 32 is communicated with the rectifying passage 33, as shown in Figure 2 , the end of the Z-shaped channel is communicated with the rectifying passage 33 downwardly, the rectifying passage 33 includes a plurality of rectifying branches arranged vertically and side by side, the two rectifying branches are connected in series, and a drain outlet is arranged below the end of the rectifying passage. In the process of the tail gas in the rectifying passage 33, the tail gas collides with the inner wall of the passage many times, so that the flow rate of the tail gas is slowed down, and the large particles or large water droplets in the tail gas are precipitated, so that a certain degree of gas-liquid separation is achieved, and the tail gas is prevented from entering the scrubbing tower at a high flow rate.

[0045] The gas passing cavity 5 is further arranged, the gas passing cavity 5 is communicated with the end of the rectifying passage 33 downwardly, as shown in Figure 2As shown, the top of the liquid tank 100 forms a buffer layer 34 in communication with the end of the rectifying channel 33, the buffer layer extends upward to form a convex portion, the over-air cavity is arranged above the convex portion, and the buffer layer 34 is in communication with the over-air cavity 5 through a plurality of over-air pipes 6.

[0046] As shown, Figure 2 As shown, the over-air pipes 6 are in communication with the over-air outlet of the over-air cavity 5, and the over-air outlet is arranged on the side wall of the over-air cavity 5 and horizontally communicates with the over-air cavity 5, so as to further buffer the tail gas flow and play a rectifying role, so that the tail gas is uniformly diffused in the scrubbing tower 4.

[0047] As shown, Figure 2 As shown, the water washing and adsorption unit includes a scrubbing tower 4, and the over-air cavity 5 is upwardly open and in communication with the scrubbing tower 4, so that the tail gas discharged through the rectifying channel 33 can enter the scrubbing tower 4 for water washing and adsorption.

[0048] The scrubbing tower 4 is provided with at least one packing layer 42 and at least one spraying assembly 43, in the embodiment, the scrubbing tower 4 is provided with upper and lower mesh plates 41, the mesh plate 41 is provided with a plurality of through holes, the lower mesh plate 41 is provided with a plurality of packings to form a packing layer 43, the packing is a prior art, such as a multi-face hollow packing, a Pall ring packing and / or a stepped ring packing, which has the characteristics of small air flow resistance and uniform liquid distribution, so as to ensure that the spraying liquid is fully contacted with the tail gas and improve the water washing and adsorption effect.

[0049] The spraying assembly 43 includes a plurality of spraying heads, the spraying heads are arranged above the packing layer 43 and below the upper mesh plate 41, and the spraying liquid sprayed by the spraying heads is used for spraying and cooling the tail gas.

[0050] In addition, the exhaust port of the scrubbing tower 4 is also provided with a fan, which is used for forming a negative pressure in the inner cavity of the scrubbing tower 4 and the inner cavity in communication therewith, so as to guide the directional flow of the tail gas and transmit the tail gas to a subsequent processing device to eliminate harmful components in the tail gas.

[0051] In addition, the tail gas treatment equipment is further covered with a shell, and the bottom of the shell is further provided with a pulley for conveniently moving the treatment equipment.

[0052] The utility model has been described above by way of example, but the utility model is not limited to the above-mentioned specific embodiments, and any modification or modification based on the utility model belongs to the scope of protection required by the utility model.

Claims

1. A plasma exhaust processing apparatus, characterized by, The exhaust gas treatment unit comprises a plasma generator (1) and a plasma reaction assembly (2), the hot plasma jet generated by the plasma generator (1) enters the reaction cavity (21) formed by the plasma reaction assembly (2) and purifies the exhaust gas in the reaction cavity (21), and the reaction cavity (21) is also connected with an external pipeline for supplying oxygen or air. The gas inlet unit comprises a plurality of gas inlet pipelines (7) arranged in a circumferential direction, and the gas outlet of the gas inlet pipeline (7) is arranged at the upper portion of the reaction cavity (21), and the exhaust gas can enter the reaction cavity (21) through the gas inlet pipeline (7). The cooling unit forms a cooling cavity, the cooling cavity is connected with the reaction cavity (21) upwardly, a plurality of baffle plates (31) facing the reaction cavity are fixedly arranged in the cooling cavity, the plurality of baffle plates (31) form a Z-shaped channel (32), the cooling cavity is also connected with a water inlet (35) and a water outlet, respectively, the cooling water supplied by the water inlet (35) flows downwardly along the Z-shaped channel (32) and is discharged through the water outlet. The water washing and adsorption unit comprises a gas scrubber (4), the gas inlet of the gas scrubber (4) is connected with the end of the Z-shaped channel (32), the gas scrubber (4) performs water washing and adsorption on the exhaust gas flowing therethrough, and the gas scrubber (4) is provided with an exhaust port connected with the outside. The plurality of baffle plates (31) are fixedly arranged on the opposite two side walls of the cooling cavity, and the baffle plate (31) has an angle inclined downwardly from outside to inside.

2. The plasma exhaust processing apparatus of claim 1, wherein, The end of the Z-shaped channel (32) is connected with the gas inlet of the gas scrubber (4) through a rectifying channel (33), the rectifying channel (33) comprises a plurality of rectifying branches arranged side by side, the adjacent two rectifying branches are connected end to end, and a drain port is arranged below the end of the rectifying channel (33).

3. The plasma exhaust processing apparatus as recited in claim 1 or 2, wherein, The rectifying channel (33) is arranged side by side with the cooling cavity and formed in a liquid storage tank (100), and the exhaust gas treatment unit and the water washing and adsorption unit are arranged side by side on the liquid storage tank (100).

4. The plasma exhaust processing apparatus of claim 3, wherein, Further comprising a gas passing cavity (5), the gas passing cavity (5) is open upwardly and connected with the gas scrubber (4), the end of the rectifying channel (33) is connected with the gas passing cavity (5) through a plurality of gas passing pipelines (6) to buffer the exhaust gas flow.

5. The plasma exhaust processing apparatus of claim 4, wherein, The gas passing outlet of the gas passing pipeline (6) connected with the gas passing cavity (5) is arranged on the side wall of the gas passing cavity (5) and connected with the gas passing cavity (5) horizontally.

6. The plasma exhaust processing apparatus of claim 5, wherein, The gas scrubber (4) is provided with at least one filler layer (42) and at least one spraying assembly (43), the spraying assembly (43) comprises a plurality of spraying heads, the spraying liquid sprayed by the spraying heads performs spraying cooling and water washing on the exhaust gas, and the filler layer (42) comprises a plurality of stacked fillers, the fillers enable the exhaust gas to be fully contacted with the spraying liquid.

7. The plasma exhaust processing apparatus of claim 6, wherein, The reaction cavity (21) is conical from large at the top to small at the bottom, a surrounding cavity (22) is formed on the outer wall of the reaction cavity (21), the surrounding cavity (22) is connected with the reaction cavity (21) through a plurality of through holes, and the surrounding cavity (22) is connected with the external pipeline to enable oxygen or air to enter the reaction cavity (21).

8. The apparatus according to any one of claims 1, 2, 4-7, wherein, A heat preservation layer (23) is arranged outside the surrounding cavity (22).

9. The plasma exhaust processing apparatus of claim 8, wherein, ​ 10. The plasma exhaust processing apparatus of claim 9, wherein, The heat preservation layer (23) is externally provided with a water cooling cavity (24), and the water cooling cavity (24) is respectively communicated with a lower water inlet and an upper water outlet.

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