Tail gas emission system for easily liquefied gas

Abstract

The utility model discloses an easily liquefied gas tail gas emission system, which comprises a gas emission device, a tail gas treatment device and a tail gas emission pipe system, the tail gas emission pipe system is used for discharging tail gas discharged by the gas emission device into the tail gas treatment device, and the tail gas emission pipe system comprises a plurality of tail gas emission pipes; the tail gas exhaust system further comprises a liquid accumulation bag, a waste liquid emptying pipe system, a waste liquid collecting tank and a tail gas communicating pipe system. The liquid accumulation bag is communicated with the tail gas emission pipe system and is used for checking whether waste liquid generated after tail gas liquefaction exists or not; the waste liquid emptying pipe system is used for guiding waste liquid accumulated in the liquid accumulation bag into the waste liquid collecting tank; the tail gas communicating pipe system is used for communicating the waste liquid collecting tank and the tail gas discharging pipe system to balance pressure of the waste liquid collecting tank and the tail gas discharging pipe system and guide waste liquid in the liquid accumulation bag into the waste liquid collecting tank. According to the utility model, easily liquefied tail gas can be smoothly discharged, and the safety of the whole system is ensured.

Description

TECHNICAL FIELD

[0001] The utility model relates to an exhaust gas discharging system of easy liquefied gas. BACKGROUND

[0002] Electronic gas is an indispensable basic supporting source material in the manufacturing process of integrated circuits, optoelectronics, microelectronics, especially ultra-large scale integrated circuits, liquid crystal display devices, semiconductor light emitting devices and semiconductor materials, and it is called the "blood" and "food" of the electronic industry. Its purity and cleanliness directly affect the quality, integration, specific technical indicators and yield of optoelectronic and microelectronic devices, and fundamentally restrict the accuracy and accuracy of circuits and devices. Hexafluorobutadiene is used in the process of semiconductor and electronic products. Under radio frequency, hexafluorobutadiene can dissociate fluorine ions, which can selectively etch the thin film of silicon compounds, i.e. reactive ion etching. Hexafluorobutadiene has the advantages of suitable depth ratio, selectivity and etching rate in the manufacturing of 3D NAND memory devices. Due to the very strict purity requirements of etching gas in semiconductor manufacturing, the purity often needs to reach 5N or above. During the process of purifying high-purity hexafluorobutadiene from crude hexafluorobutadiene, a small amount of hexafluorobutadiene waste gas is often discharged.

[0003] Hexafluorobutadiene is a low-pressure liquefied hydrocarbon, and its normal temperature boiling point (about 6℃) is higher than that of high-pressure liquefied hydrocarbon. Hexafluorobutadiene waste gas is prone to liquefy and accumulate in the discharge pipeline in winter (environmental temperature ≤ 6℃), blocking the discharge pipeline and affecting normal process discharge. In addition, hexafluorobutadiene is a flammable, explosive and toxic gas, and a large amount of hexafluorobutadiene waste liquid accumulated in the discharge pipeline also poses a certain safety hazard.

[0004] At present, the discharge pipeline of hexafluorobutadiene is insulated by insulation materials or made into a vacuum jacketed pipe.

[0005] The existing two kinds of hexafluorobutadiene waste gas discharge systems are described in detail below.

[0006] The first kind of hexafluorobutadiene waste gas discharge system is composed of a hexafluorobutadiene purification system 11, a process exhaust gas discharge pipe 12, a pipe insulation layer 13, a tail gas treatment system 14 and a treated qualified tail gas high-altitude discharge pipe 15, as shown in Figure 1 This method mainly relies on the pipe insulation layer 13 on the process exhaust gas discharge pipe 12 for insulation to reduce the influence of environmental temperature (mainly low temperature in winter) on the temperature of the exhaust gas in the process exhaust gas discharge pipe 12.

[0007] There are the following problems: because the tail gas exhaust pipe of the hexafluorobutadiene purification system is more, the arrangement is more complex, and various instruments and valves are arranged on part of the pipeline, so that it is difficult to insulate the pipeline, the construction quality of the insulation layer often cannot reach the expectation, and defects such as hollowing and cracking exist (especially at the pipeline arrangement complex and instrument valve position), so that the insulation layer is not tightly connected with the main pipeline, a cold bridge effect is formed, heat loss is aggravated, and the tail gas pipeline is locally blocked below the liquefaction of hexafluorobutadiene in winter.

[0008] The second kind, the exhaust gas emission system of hexafluorobutadiene is composed of hexafluorobutadiene purification system 21, vacuum jacketed process exhaust gas discharge pipe 22, exhaust gas treatment system 23, and qualified exhaust gas high-altitude discharge pipe 24 after treatment, as shown in Figure 2 This method mainly relies on the insulation material of the process exhaust gas discharge pipe 22 to insulate, and reduce the influence of the ambient temperature (mainly in winter) on the exhaust gas temperature in the process exhaust gas discharge pipe.

[0009] There are the following problems:

[0010] Because the tail gas exhaust pipe of the hexafluorobutadiene purification system is more, the arrangement is more complex, and various instruments and valves are arranged on part of the pipeline, so that it is difficult to insulate the pipeline, the construction quality of the insulation layer often cannot reach the expectation, and defects such as hollowing and cracking exist (especially at the pipeline arrangement complex and instrument valve position), so that the insulation layer is not tightly connected with the main pipeline, a cold bridge effect is formed, heat loss is aggravated, and the tail gas pipeline is locally blocked below the liquefaction of hexafluorobutadiene in winter.

[0011] The unit price of the vacuum jacketed pipe and the vacuum insulated valve is about 10 times of the unit price of the ordinary pipe and valve, and the market still cannot find the corresponding vacuum insulated valve for part of the complex structure valve. Practical new type content

[0012] In order to solve the above technical problems, the utility model provides a tail gas emission system of easy liquefied gas.

[0013] In order to achieve the above purpose, the technical scheme of the utility model is as follows:

[0014] The utility model discloses a tail gas emission system of easy liquefied gas, which comprises: a gas emission device, a tail gas treatment device and a tail gas discharge pipe system.

[0015] The tail gas emission system further comprises: a liquid accumulation bag, a waste liquid discharge pipe system, a waste liquid collection tank and a tail gas communication pipe system.

[0016] The liquid accumulation bag is communicated with the tail gas discharge pipe system and is used for checking whether waste liquid generated after liquefaction of tail gas exists.

[0017] The waste liquid exhaust pipe system is used to guide the waste liquid accumulated in the liquid accumulation bag into the waste liquid collecting tank.

[0018] The tail gas communication pipe system is used to communicate the waste liquid collecting tank and the tail gas exhaust pipe system, balance the pressure of both, and guide the waste liquid in the liquid accumulation bag into the waste liquid collecting tank.

[0019] Based on the above technical solutions, the following improvements can be made:

[0020] As a preferred solution, the liquid accumulation bag is provided with a visual window.

[0021] As a preferred solution, the liquid accumulation bag is communicated with any tail gas exhaust pipe in the tail gas exhaust pipe system, and the communication point is the lowest point of the tail gas exhaust pipe system.

[0022] As a preferred solution, the waste liquid exhaust pipe system comprises a waste liquid exhaust pipe, an exhaust valve installed on the waste liquid exhaust pipe, and a metal hose.

[0023] The liquid accumulation bag is communicated with the waste liquid collecting tank through the waste liquid exhaust pipe and the metal hose in sequence.

[0024] As a preferred solution, the waste liquid collecting tank is provided with a liquid phase plug-in pipe and a gas phase outlet pipe.

[0025] One end of the liquid phase plug-in pipe extends into the tank bottom of the waste liquid collecting tank, the other end is communicated with the waste liquid exhaust pipe system, and an inlet valve is installed on the liquid phase plug-in pipe.

[0026] One end of the gas phase outlet pipe is communicated with the tank of the waste liquid collecting tank, the other end is communicated with the tail gas communication pipe system, and an outlet valve is installed on the gas phase outlet pipe.

[0027] As a preferred solution, the tail gas communication pipe system comprises a tail gas communication pipe, a communication valve installed on the tail gas communication pipe, and a metal hose.

[0028] The tail gas exhaust pipe is communicated with the waste liquid collecting tank through the tail gas communication pipe and the metal hose in sequence.

[0029] As a preferred solution, a pipe heating assembly and a thermal insulation layer are installed on each tail gas exhaust pipe.

[0030] As a preferred solution, the pipe heating assembly is an electric heating tape.

[0031] As a preferred solution, the tail gas exhaust system further comprises a nitrogen gas purging pipe system.

[0032] The nitrogen gas purging pipe system comprises a nitrogen gas input pipe, and a switch valve and a one-way valve installed on the nitrogen gas input pipe.

[0033] The nitrogen gas input pipe is used to introduce nitrogen gas into the tail gas exhaust pipe system.

[0034] As a preferred solution, the nitrogen gas input pipe is in communication with any of the tail gas discharge pipes of the tail gas discharge system, and the communication point is the highest point of the tail gas discharge system.

[0035] The utility model discloses an easy liquefied gas's tail gas discharge system, it has the following beneficial effects:

[0036] When the waste liquid produced after the liquefaction of the tail gas exists in the tail gas discharge system, can be found in time. BRIEF DESCRIPTION OF DRAWINGS

[0037] In order to more clearly illustrate the technical scheme of the embodiment of the utility model, the following will be needed to use the drawing in the embodiment briefly introduced, it should be understood, the following drawings only shows some embodiments of the utility model, therefore should not be regarded as the limitation to the range, for the ordinary skilled person in the art, under the premise of not paying the creative labor, still can obtain other related drawings according to these drawings.

[0038] Figure 1 The first tail gas discharge system provided by the prior art is schematically shown.

[0039] Figure 2 The second tail gas discharge system provided by the prior art is schematically shown.

[0040] Figure 3 The tail gas discharge system provided by the embodiment of the utility model is schematically shown.

[0041] Figure 4 The liquid accumulation bag provided by the embodiment of the utility model is schematically shown.

[0042] Figure 5 The waste liquid discharge pipe system provided by the embodiment of the utility model is schematically shown.

[0043] Figure 6 The waste liquid collection tank provided by the embodiment of the utility model is schematically shown.

[0044] Figure 7 The tail gas communication pipe system provided by the embodiment of the utility model is schematically shown.

[0045] Figure 8 The tail gas discharge pipe provided by the embodiment of the utility model is schematically shown.

[0046] Figure 9 The nitrogen gas purging pipe system provided by the embodiment of the utility model is schematically shown.

[0047] Wherein: 11-hexafluorobutadiene purification system, 12-process tail gas discharge pipe, 13-pipeline insulation layer, 14-tail gas treatment system, 15-tail gas high-altitude discharge pipe;

[0048] 21-hexafluorobutadiene purification system, 22-vacuum jacketed process tail gas discharge pipe, 23-tail gas treatment system, 24-tail gas high-altitude discharge pipe;

[0049] 31-gas discharge device, 32-tail gas treatment device, 33-tail gas discharge pipe system, 331-tail gas discharge pipe, 34-liquid trap, 341-visual window, 35-waste liquid discharge pipe system, 351-waste liquid discharge pipe, 352-discharge valve, 353-metal hose, 36-waste liquid collection tank, 361-liquid phase insertion bottom pipe, 362-gas phase outlet pipe, 363-inlet valve, 364-outlet valve, 37-tail gas communication pipe system, 371-tail gas communication pipe, 372-communication valve, 373-metal hose, 381-pipeline heating assembly, 382-insulation layer, 39-nitrogen purge pipe system, 391-nitrogen input pipe, 392-on-off valve, 393-one-way valve, 40-tail gas high-altitude discharge pipe;

[0050] a-lowest point, b-highest point. DETAILED DESCRIPTION

[0051] The preferred embodiments of the utility model will be described in detail below with reference to the drawings.

[0052] The technical solutions in the embodiments of the utility model will be described clearly and completely below with reference to the drawings in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, rather than all the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by those skilled in the art without creative labor fall within the protection scope of the utility model.

[0053] The expression of "including" element is an "open" expression, and the "open" expression only means that the corresponding component or step exists, and should not be interpreted as excluding additional components or steps.

[0054] In order to achieve the purpose of the utility model, some embodiments of the tail gas discharge system of the easily liquefied gas, the tail gas discharge system comprises: gas discharge device 31, tail gas treatment device 32 and tail gas discharge pipe system 33, tail gas discharge pipe system 33 is used for discharging the tail gas discharged by gas discharge device 31 into tail gas treatment device 32, and tail gas discharge pipe system 33 comprises: a plurality of tail gas discharge pipes 331;

[0055] The tail gas discharge system further comprises: liquid trap 34, waste liquid discharge pipe system 35, waste liquid collection tank 36 and tail gas communication pipe system 37.

[0056] The liquid accumulation bag 34 is communicated with the tail gas discharge pipeline system 33, and is used for checking whether waste liquid generated after liquefaction of the tail gas exists;

[0057] The waste liquid discharge pipeline system 35 is used for guiding the waste liquid accumulated in the liquid accumulation bag 34 into the waste liquid collecting tank 36;

[0058] The tail gas communication pipeline system 37 is used for communicating the waste liquid collecting tank 36 and the tail gas discharge pipeline system 33, balancing the pressure of the two, and guiding the waste liquid in the liquid accumulation bag 34 into the waste liquid collecting tank 36.

[0059] The tail gas discharge system of the liquefiable gas disclosed in the embodiment can be used for discharging the tail gas of hexafluorobutadiene, and the gas discharge device 31 is a hexafluorobutadiene purification system. In other embodiments, the tail gas discharge system can also be used for discharging the tail gas of other liquefiable gases, which is not limited herein.

[0060] The gas treated by the tail gas treatment device 32 is discharged through the treated qualified tail gas high-altitude discharge pipeline 40.

[0061] In order to further optimize the implementation effect of the utility model, in some other embodiments, the remaining features are the same in technology, and the difference lies in that the liquid accumulation bag 34 is provided with a visible window 341, and the visible window 341 can be but is not limited to a glass window.

[0062] In order to further optimize the implementation effect of the utility model, in some other embodiments, the remaining features are the same in technology, and the difference lies in that the liquid accumulation bag 34 is communicated with any tail gas discharge pipeline 331 of the tail gas discharge pipeline system 33, and the communication point is the lowest point a of the tail gas discharge pipeline system 33.

[0063] In order to further optimize the implementation effect of the utility model, in some other embodiments, the remaining features are the same in technology, and the difference lies in that the waste liquid discharge pipeline system 35 comprises a waste liquid discharge pipeline 351, a discharge valve 352 mounted on the waste liquid discharge pipeline and a metal hose 353.

[0064] The liquid accumulation bag 34 is communicated with the waste liquid collecting tank 36 through the waste liquid discharge pipeline 351 and the metal hose 353 in sequence.

[0065] The discharge valve 352 can be but is not limited to a double valve.

[0066] In order to further optimize the implementation effect of the utility model, in some other embodiments, the remaining features are the same in technology, and the difference lies in that a liquid phase plug bottom pipe 361 and a gas phase outlet pipe 362 are mounted on the waste liquid collecting tank 36.

[0067] One end of the liquid phase plug bottom pipe 361 extends into the bottom of the tank of the waste liquid collecting tank 36, the other end is communicated with the waste liquid discharge pipeline system 35, and an inlet valve 363 is mounted on the liquid phase plug bottom pipe 361.

[0068] One end of the gas phase outlet pipe 362 is in communication with the tank of the waste liquid collection tank 36, the other end is in communication with the tail gas communication pipeline system 37, and an outlet valve 364 is installed on the gas phase outlet pipe 362.

[0069] The inlet valve 363 and the outlet valve 364 can be, but are not limited to, double valves.

[0070] In order to further optimize the implementation effect of the utility model, in some other embodiments, the remaining features are the same, and the difference lies in that the tail gas communication pipeline system 37 comprises: a tail gas communication pipe 371, a communication valve 372 installed on the tail gas communication pipe, and a metal hose 373;

[0071] The tail gas discharge pipe 331 is in communication with the waste liquid collection tank 36 through the tail gas communication pipe 371 and the metal hose 373 in sequence.

[0072] The communication valve 372 can be, but is not limited to, a double valve.

[0073] In order to further optimize the implementation effect of the utility model, in some other embodiments, the remaining features are the same, and the difference lies in that a pipeline heating assembly 381 and a heat preservation layer 382 are installed on each tail gas discharge pipe 331.

[0074] The pipeline heating assembly 381 can be, but is not limited to, an electric heating tape wound on the tail gas discharge pipe 331. The electric heating tape can prevent freezing, maintain temperature, prevent condensation, and maintain process temperature. The outside of the electric heating tape is attached with a heat preservation layer 382.

[0075] The utility model installs the pipeline heating assembly 381 on each tail gas discharge pipe 331. Even if the construction quality of the heat preservation layer 382 causes local poor heat preservation effect, the heating of the heating tape can offset the heat loss, and ensure that the temperature of the tail gas discharge pipe is always maintained at 25-30 DEG C in the case that the electric heating tape is not failed or the heat preservation layer 382 is not failed in a large area, and the hexafluorobutadiene tail gas is not liquefied at low temperature.

[0076] In order to further optimize the implementation effect of the utility model, in some other embodiments, the remaining features are the same, and the difference lies in that the tail gas discharge system further comprises: a nitrogen purging pipe system 39;

[0077] The nitrogen purging pipe system 39 comprises: a nitrogen input pipe 391, and a switch valve 392 and a one-way valve 393 installed on the nitrogen input pipe 391;

[0078] The nitrogen input pipe 391 is used to introduce nitrogen into the tail gas discharge pipe system 33.

[0079] The tail gas emission system adds a nitrogen purging pipe system 39, after the process tail gas is discharged to the tail gas treatment equipment 32, the tail gas emission pipe system 33 is purged and replaced 2-3 times by nitrogen first, generally, the tail gas system is basically nitrogen atmosphere, the hexafluorobutadiene content is less than 0.1%, below the lower limit of explosion (1%), and the safety of the whole tail gas emission system is ensured.

[0080] Further, on the basis of the above embodiment, the nitrogen input pipe 391 is communicated with any tail gas emission pipe 331 in the tail gas emission pipe system 33, and the communication point is the highest point b of the tail gas emission pipe system 33.

[0081] In summary, when the tail gas emission system of the liquefiable gas with all the technical features works, the working process is as follows:

[0082] During the operation of the hexafluorobutadiene purification system, the electric heating band is continuously heated, and the temperature of the tail gas emission pipe 331 is always kept at 25-30 DEG C by cooperating with the heat preservation layer 382.

[0083] The normal process tail gas is discharged to the tail gas treatment equipment 32, and the tail gas emission pipe system 33 is purged and replaced 2-3 times by nitrogen first, generally, the tail gas emission system is basically nitrogen atmosphere (the hexafluorobutadiene content is less than 0.1%).

[0084] In winter, the on-site operator regularly inspects the liquid accumulation bag 34, and whether liquid hexafluorobutadiene is produced is checked through the visual window 341 of the liquid accumulation bag 34, if liquid hexafluorobutadiene is produced, the valves involved in the waste liquid discharge pipe system 35, the waste liquid collection tank 36 and the tail gas communication pipe system 37 are opened, so that the waste liquid in the liquid accumulation bag 34 is smoothly discharged into the waste liquid collection tank 36.

[0085] The utility model discloses a tail gas emission system of liquefiable gas, which has the following beneficial effects:

[0086] When there is waste liquid produced by the liquefaction of tail gas in the tail gas emission pipe system 33, it can be found in time. Under the joint action of the waste liquid discharge pipe system 35 and the tail gas communication pipe system 37, the waste liquid accumulated in the liquid accumulation bag 34 is discharged into the waste liquid collection tank 36, ensuring the safety of the whole tail gas emission system.

[0087] In the description of the utility model, it is understood that the orientation or position relationship indicated by the terms "coaxial", "bottom", "one end", "top", "middle", "the other end", "upper", "one side", "top", "inner", "front", "central", "both ends" is based on the orientation or position relationship shown in the drawings, and is only for the convenience of describing the utility model and simplifying the description, and cannot be understood as a limitation on the utility model.

[0088] In the utility model, unless another definite provision and limitation, the term " install ", " set ", " connect ", " fix ", " screw " and so on term should do broad sense understanding, for example, can be fixed connection, also can be detachable connection, or be integrated; can be mechanical connection, also can be electrical connection; can be direct connection, also can be indirectly connected through intermediate medium, can be two element internal communication or two element's mutual action relation, unless another definite limitation, for the ordinary skill in the art, can understand the above-mentioned term in the utility model specific meaning according to specific circumstances.

[0089] The basic principle and main features of the utility model and the advantages of the utility model are shown and described above, and those skilled in the art should understand that the utility model is not limited by the above examples, and the above examples and descriptions in the specification are only to illustrate the principles of the utility model. Without departing from the spirit and scope of the utility model, various changes and improvements can be made to the utility model. These changes and improvements fall within the scope of the claimed utility model. The scope of protection of the utility model is defined by the appended claims and their equivalents.

Claims

1. Exhaust system for liquefiable gases, including: Gas exhaust equipment, tail gas treatment equipment and tail gas exhaust piping system, the tail gas exhaust piping system is used to discharge the tail gas discharged from the gas exhaust equipment into the tail gas treatment equipment, the tail gas exhaust piping system includes: a plurality of tail gas exhaust pipes; It is characterized in that the exhaust gas emission system further comprises: a liquid accumulation bag, a waste liquid discharge pipe system, a waste liquid collection tank and an exhaust gas connecting pipe system; The liquid collection bag is connected to the tail gas discharge pipe system and is used to check whether there is waste liquid generated after the tail gas is liquefied; The waste liquid drain pipe system is used to guide the waste liquid in the liquid bag into the waste liquid collection tank; The tail gas connecting pipe system is used to connect the waste liquid collection tank and the tail gas discharge pipe system, balance the pressure of the two, and guide the waste liquid in the liquid accumulation bag into the waste liquid collection tank.

2. The exhaust gas emission system according to claim 1, characterized in that: The fluid collection bag is provided with a visual window.

3. The exhaust emission system according to claim 1, characterized in that: The liquid accumulation bag is connected to any tail gas exhaust pipe in the tail gas exhaust pipe system, and the connection point is the lowest point of the tail gas exhaust pipe system.

4. The exhaust emission system according to claim 1, characterized in that: The waste liquid drain pipe system includes: a waste liquid drain pipe, a drain valve installed on the waste liquid drain pipe, and a metal hose; The liquid accumulation bag is connected to the waste liquid collection tank through the waste liquid drain pipe and the metal hose in sequence.

5. The exhaust gas emission system according to claim 1, characterized in that: A liquid phase bottom plug tube and a gas phase outlet pipe are installed on the waste liquid collection tank; One end of the liquid phase bottom plug tube extends into the bottom of the waste liquid collection tank, and the other end is connected to the waste liquid discharge pipe system, and an inlet valve is installed on the liquid phase bottom plug tube; One end of the gas phase outlet pipe is communicated with the inside of the waste liquid collection tank, and the other end is communicated with the tail gas communication pipe system, and an outlet valve is installed on the gas phase outlet pipe.

6. The exhaust gas emission system according to claim 1, characterized in that: The exhaust gas connecting pipe system includes: an exhaust gas connecting pipe, a connecting valve installed on the exhaust gas connecting pipe, and a metal hose; The tail gas exhaust pipe is connected to the waste liquid collection tank through the tail gas connecting pipe and the metal hose in sequence.

7. The exhaust gas emission system according to any one of claims 1 to 6, characterized in that: A pipe heating component and a heat insulation layer are installed on each of the tail gas exhaust pipes.

8. The exhaust emission system according to claim 7, characterized in that: The pipeline heating component is an electric heating tape.

9. The exhaust gas emission system according to any one of claims 1 to 6, characterized in that: The tail gas emission system further includes: a nitrogen purge piping system; The nitrogen purge piping system includes: a nitrogen inlet pipe and a switch valve and a one-way valve installed on the nitrogen inlet pipe; The nitrogen inlet pipe is used to introduce nitrogen into the tail gas exhaust pipe system.

10. The exhaust emission system according to claim 9, characterized in that: The nitrogen input pipe is connected to any tail gas exhaust pipe in the tail gas exhaust pipe system, and the connection point is the highest point of the tail gas exhaust pipe system.

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