JP2010201358A - Exhaust gas treatment system and operation method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To fully use the treatment capacity of a treatment agent of an exhaust gas treatment apparatus as much as possible, using a centralized piping connecting structure. <P>SOLUTION: An exhaust gas treatment system includes: a plurality of exhaust gas treatment units 14a-14d including treatment tanks 40; a common inlet duct 30 into which an exhaust gas supplied to the plurality of exhaust gas treatment units flows; an outlet duct 32 for exhausting the gas treated in the exhaust gas treatment units; and a central control section 56 for controlling the operation conditions of the exhaust gas treatment units. The exhaust gas treatment system has: sections 42 installed on the downstream sides of the exhaust gas treatment units, and detecting the exhaust gas treatment capacities of the exhaust gas treatment units; outlet valves 44 installed in treated gas outflow lines 24 extending from the exhaust gas treatment units and connected to the outlet duct 32; and treated gas returning lines 46 diverged on the upstream side of the outlet valves from the treated gas outflow lines, and converged to the common inlet duct. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an exhaust gas treatment system and an operation method thereof, and more particularly to an exhaust gas treatment system and an operation method thereof for treating exhaust gas discharged in a manufacturing process of a semiconductor device, a liquid crystal panel, and the like.

For example, in the semiconductor manufacturing industry, an etching apparatus uses a PFC (Perfluoro Compounds) gas such as CF ₄ , CHF ₃ , or C ₄ F ₈ as an etching gas, and a CVD apparatus adheres to the chamber during a wafer film formation process. PFC gas such as C ₂ F ₆ or NF ₃ is used as a cleaning gas for the obtained product. These PFC gases have a high global warming potential, and emission regulations for the gases are strengthened.

  For this reason, as shown in FIG. 1, an exhaust gas treatment device 14 is connected to a manufacturing device 10 such as a semiconductor manufacturing device or a liquid crystal manufacturing device such as an etching device, an ashing device or a CVD device via an exhaust vacuum pump 12, In a treatment tank (reaction tank) 16 of the exhaust gas treatment device 14, it is widely performed to decompose, remove, and release PFC gas in the exhaust gas. A pressure gauge 20 and an inlet valve 22 are installed in the exhaust gas inflow line 18 on the upstream side of the treatment tank 16 of the exhaust gas processing apparatus 14, and a flow meter 26 and a blower 28 are installed in the processed gas outflow line 24 on the downstream side, respectively. .

  In the manufacture of semiconductor devices, a plurality of semiconductor manufacturing devices are usually used. For this reason, as shown in FIG. 2, exhaust gases from a plurality of semiconductor manufacturing apparatuses 10 are once collected in a common inlet duct (concentrated exhaust duct) 30, and a plurality of units each having a treatment tank 16 in the common inlet duct 30. It is also possible to adopt a so-called centralized pipe connection method in which the exhaust gas inflow lines 18 of the exhaust gas treatment apparatuses 14 are connected and the processed gas outflow lines 24 of a plurality of exhaust gas treatment apparatuses 14 are connected to the outlet duct 32. ing.

  The exhaust gas treatment system adopting the centralized pipe connection method shown in FIG. 2 is a process compared to the exhaust gas treatment system adopting the individual connection method shown in FIG. Even if the flow rate of the exhaust gas fluctuates for each manufacturing apparatus or the number of operating devices of the connected exhaust gas processing apparatus changes, stable processing can be performed to cope with a plurality of exhaust gas processing apparatuses. Further, even if any exhaust gas treatment device fails, the operation can be continued without stopping the operation of the manufacturing apparatus by operating another exhaust gas treatment device. In general, a manufacturing apparatus such as a semiconductor device or a liquid crystal panel takes time to restart the apparatus, and it is important to enable continuous operation without stopping the manufacturing apparatus.

  As an exhaust gas treatment system adopting this centralized pipe connection system, the flow rate of the exhaust gas to each exhaust gas treatment device is made constant by adjusting the flow rate based on the measured value with the flow meter provided upstream of the exhaust gas treatment device. The thing which made it do is proposed (refer patent document 1).

JP 2005-279320 A

Among exhaust gas treatment equipment, especially in dry exhaust gas treatment equipment that removes PFC gas, etc. in exhaust gas by adsorbing to the treatment agent, the processing capacity of the treatment agent in the treatment tank (treatment column) is used up. Once (if it breaks through), it must be replaced with a new treatment tank. For example downstream guaranteed value of the exhaust gas treatment apparatus, for example, In the exhaust gas contains CF ₄ falls below 95% rate removal of CF _4, so that it is determined that the replacement timing of the treatment tank (breakthrough). However, even if the CF ₄ removal rate is less than 95%, the treatment capacity of the treatment agent in the treatment tank still remains, and generally the treatment ability of the expensive treatment agent has not been used up.

  The present invention has been made in view of the above circumstances, and an exhaust gas treatment system capable of using as much as possible the treatment capacity of a treatment agent of an exhaust gas treatment device by utilizing the structure of a centralized pipe connection system and its operation It aims to provide a method.

  The invention according to claim 1 is a plurality of exhaust gas treatment devices each provided with a treatment tank, a common inlet duct into which exhaust gas supplied to the plurality of exhaust gas treatment devices flows, and a treatment processed by the exhaust gas treatment device. An exhaust duct for exhausting exhaust gas and a centralized control unit for controlling the operating conditions of each exhaust gas treatment device, wherein the exhaust gas treatment system is installed downstream of each exhaust gas treatment device, Means for detecting the exhaust gas treatment capacity, an outlet valve installed in each treated gas outflow line extending from each exhaust gas treatment device and connected to the outlet duct, and from the treated gas outflow line upstream of the outlet valve An exhaust gas treatment system comprising a treated gas return line that branches and joins the common inlet duct.

  As a result, even if the exhaust gas treatment capacity of one exhaust gas treatment device of a plurality of exhaust gas treatment devices is reduced, the treated gas processed by the one exhaust gas treatment device is not discharged from the outlet duct. The treatment agent in the treatment tank of the one exhaust gas treatment device is treated by returning to the common inlet duct through the return line and treating the exhaust gas in the common inlet duct with another exhaust gas treatment device including the one exhaust gas treatment device. You can use up your abilities as much as possible.

  According to a second aspect of the present invention, the common inlet duct is provided with a duct pressure gauge for detecting the pressure in the common inlet duct, and the central control unit is based on the pressure measured by the duct pressure gauge. The exhaust gas treatment system according to claim 1, wherein the exhaust gas flow rate supplied to each exhaust gas treatment device is controlled.

  Thus, wasteful driving force and power consumption for the exhaust gas treatment operation can be suppressed by controlling the exhaust gas flow rate supplied to each exhaust gas treatment device according to the pressure in the common inlet duct.

A third aspect of the present invention is the exhaust gas treatment system according to the first or second aspect, wherein the central control unit and the service support base are connected by a LAN.
In this way, by connecting the centralized control unit that controls the operating conditions of each exhaust gas treatment device and the service support base via LAN, the operation status of each exhaust gas treatment equipment is managed at the service support base, and unified management of treatment tanks, It is possible to prepare a timely alternative treatment tank and predict failure.

  According to a fourth aspect of the present invention, there are provided a plurality of exhaust gas treatment devices each provided with a treatment tank, a common inlet duct into which exhaust gas supplied to the plurality of exhaust gas treatment devices flows, and a treatment processed by the exhaust gas treatment device. An exhaust gas treatment system comprising an outlet duct for exhausting exhaust gas and a centralized control unit for controlling operating conditions of each exhaust gas treatment device, wherein the exhaust gas treatment is installed downstream of each exhaust gas treatment device. Each exhaust gas treatment capability is detected by the capability detection means, and when the exhaust gas treatment capability of one of the plurality of exhaust gas treatment devices exceeds a first predetermined level, the exhaust gas treatment device is processed by the one exhaust gas treatment device. The treated gas is returned to the common inlet duct without flowing the treated gas through the outlet duct.

The first predetermined level is, for example, 50 ppm, which serves as a reference for replacing the processing tank by using up the processing capacity of the processing agent when a gas detector for detecting the CF ₄ gas concentration is used as the exhaust gas processing capacity detecting means. .

  According to a fifth aspect of the present invention, when the exhaust gas treatment capability of one of the plurality of exhaust gas treatment devices exceeds a second predetermined level, the exhaust gas flows into the one exhaust gas treatment device. 5. The operation method of an exhaust gas treatment system according to claim 4, wherein the operation is stopped and a signal for exchanging the treatment tank provided in the one exhaust gas treatment device is issued.

The second predetermined level is, for example, 200 ppm when the gas detector for detecting the CF ₄ gas concentration is used as the exhaust gas processing capacity detecting means, and is replaced when the processing capacity reaches 50 ppm conventionally. The processing capacity of the treating agent that has been used can be extended to 200 ppm.

  The invention according to claim 6 detects the pressure in the common inlet duct with a duct pressure gauge, and controls the exhaust gas flow rate supplied to each exhaust gas treatment device based on the pressure measured with the duct pressure gauge. A method for operating an exhaust gas treatment system according to claim 4 or 5.

  The invention according to claim 7 is a method for operating an exhaust gas treatment system according to any one of claims 4 to 6, wherein data from the central control unit is transmitted to a service support base through a LAN. It is.

  According to the exhaust gas treatment system and the operating method of the present invention, even if the exhaust gas treatment capacity of one exhaust gas treatment device of a plurality of exhaust gas treatment devices decreases, the treatment tank of the one exhaust gas treatment device is used for exhaust gas treatment. By continuing to use, the processing agent in the processing tank can be used up as much as possible.

It is a systematic diagram of an exhaust gas treatment system adopting a conventional individual connection method. It is a systematic diagram of an exhaust gas treatment system adopting a conventional centralized pipe connection method. 1 is a system diagram of an exhaust gas treatment system according to an embodiment of the present invention. It is a schematic sectional drawing of the processing tank of the waste gas processing system shown in FIG. It is a schematic sectional drawing which shows the other example of a processing tank. It is a systematic diagram of the exhaust gas treatment system of other embodiment of this invention. It is a systematic diagram of the exhaust gas treatment system of further another embodiment of the present invention. It is a systematic diagram of the exhaust gas treatment system of further another embodiment of the present invention.

  An embodiment of the present invention will be described with reference to FIGS. 1 to 8, the same or corresponding members are denoted by the same reference numerals, and redundant description is omitted.

FIG. 3 shows an exhaust gas treatment system according to an embodiment of the present invention, and FIG. 4 shows a schematic cross-sectional view of a treatment tank provided in the exhaust gas treatment system shown in FIG. As shown in FIG. 3, a plurality of (in the figure, five) semiconductor manufacturing apparatuses 10 such as semiconductor manufacturing apparatuses are connected to this exhaust gas treatment system, and CF _{4 and the} like discharged from these manufacturing apparatuses 10 The exhaust gas containing the PFC gas is once collected in the common inlet duct 30 through the vacuum pump 12.

The common inlet duct 30 is connected to the exhaust gas inflow lines 18 of a plurality (four in this example) of the exhaust gas treatment devices 14a to 14d each having a treatment tank 40. Each exhaust gas inflow line 18 is provided with an inlet valve 22. Further, in the treated gas outflow line 24 extending from the treatment tank 40, a flow meter (or pressure gauge) 26, a blower 28, an exhaust gas treatment capacity detecting means 42 and an outlet valve 44 are installed. In this example, a gas detector that detects the concentration of untreated PFC gas such as CF ₄ is used as the exhaust gas treatment capacity detection means 42. Since CO flows out when the decomposition rate of the PFC gas decreases, the exhaust gas treatment capacity detection means (gas detector) 42 may detect the CO concentration. Other examples of the exhaust gas treatment capacity detection means include means for detecting a change in the weight of the treatment tank accompanying the exhaust gas treatment.

  If the relationship between the rotation speed of the blower 28 and the suction amount of exhaust gas is known, the flow meter 26 may be omitted. A pressure gauge may be used instead of the flow meter 26.

  Each of the exhaust gas treatment devices 14a to 14d is provided with a treated gas return line 46 branched from the treated gas outflow line 24 on the upstream side of the outlet valve 44 and joined to the common inlet duct 30, and this treated gas return line. A return line valve 48 and a blower 50 are installed at 46. Instead of this blower 50, a hermetic pump may be used.

  A duct pressure gauge 52 that detects the pressure in the duct 30 is installed in the common inlet duct 30.

  Each of the exhaust gas treatment devices 14a to 14d is provided with the valves 22, 32, 48 and the blowers 28, 50 based on signals from a flow meter (or pressure gauge) 26, an exhaust gas treatment capacity detection means (gas detector) 42, and the like. A control unit 54 for controlling is provided, and the control unit 54 and the duct pressure gauge 52 are connected to a central control panel 56 as a central control unit. The central control panel 56 is connected to a computer 60 at a service support base through a LAN transmission cable 58.

  As shown in FIG. 4, the treatment tank 40 in each of the exhaust gas treatment apparatuses 14 a to 14 d is connected to the exhaust gas inflow line 18 and the treated gas outflow line 24 to perform heat exchange between the exhaust gas and the treated gas. An exchanger 62, a heater chamber 66 in which a heater 64 is housed, and a processing agent filling chamber 68 provided concentrically with the heater chamber 66 outside the heater chamber 66 are provided. The processing agent filling chamber 68 is filled with a processing agent 70. The heat exchanger 62 and the heater chamber 66 are connected by an inlet-side internal pipe 72, and the processing agent filling chamber 68 and the heat exchanger 62 are connected by an outlet-side internal pipe 74. Further, the periphery of the processing agent filling chamber 68 and the internal pipes 72 and 74 is covered with a heat insulating material 76.

  Thus, for example, the exhaust gas at 25 ° C. flows into the heat exchanger 62 through the exhaust gas inflow line 18, is heated by the heat exchanger 62, and further heated by passing through the heater chamber 66. Then, it flows into the processing agent filling chamber 68 and is contacted with the processing agent 70 filled in the processing agent filling chamber 68 to be processed. The heat exchanger 62 cools the processing agent to, for example, 30 to 100 ° C. and a maximum of 140 ° C. After that, it is discharged through the treated gas outflow line 24.

  In this example, the exhaust gas is treated by contacting the exhaust gas in a state where the treatment agent 70 is heated to near 700 ° C. The treatment agent 70 in the treatment tank 40 is heated by heating the air that has flowed into the heater chamber 66, but the temperature of the treatment tank 40 is raised by continuously flowing air at room temperature from the exhaust gas inflow line 18. It takes time to raise the temperature of the treatment agent 70.

  Therefore, in this example, the outlet side internal pipe 74 and the inlet side internal pipe 72 are connected by a circulation pipe 82 in which a circulation valve 78 and a blower 80 are installed, and the temperature rising gas discharge is stopped in the treated gas outflow line 24. A valve 90 is provided so that air that has flowed into the outlet-side internal pipe 74 returns to the inlet-side internal pipe 72 through the circulation pipe 82 and circulates while the temperature of the processing tank 40 is rising. In this way, by heating the air once heated in the heater chamber 66 in the heater chamber 66 again, the temperature rise of the air and the processing agent 70 can be promoted.

  As shown in FIG. 4, when the high-temperature air before being cooled by the heat exchanger 62 flows in the circulation pipe 82, the circulation valve 78 and the blower 80 installed in the circulation pipe 82 have a heat resistant temperature. It may exceed. In such a case, as shown in FIG. 5, a circulation pipe 84 that connects the treated gas outflow line 24 and the exhaust gas inflow line 18 is provided downstream of the heat exchanger 62. A blower 88 may be installed.

  In this case, the air being heated in the treatment tank 40 flows from the treated gas outflow line 24 through the circulation pipe 84 into the exhaust gas inflow line 18 and circulates. Also by this, the heating time of the processing agent 70 can be shortened.

In this example, as the treating agent 70, a molar ratio of Al (OH) ₃ and Ca (OH) ₂ having a predetermined composition (median diameter (average particle diameter) of 55 to 160 μm) is 3: 7 to 5: 5. A mixture that has been sufficiently calcined at 430 to 890 ° C. (preferably 580 to 780 ° C.) is used. Then, the treatment agent 70 is filled in the treatment agent filling chamber 68 in the treatment tank 40, and brought into contact with a PFC gas such as CF ₄ at 550 to 850 ° C. (and a temperature higher than the firing temperature). The gas is decomposed and fixed to the treatment agent 70 as CaF ₂ . At this time, it is preferable that the moisture contained in the treatment agent 70 is small, and it is preferably 5 wt% or less, preferably 3.5 wt% or less, more preferably 2.7 wt% or less. The median diameter is generally referred to as d50, and is a diameter where the larger side and the smaller side are equivalent when the powder is divided into two from a certain particle diameter. In this example, a volume reference is used. In actual measurement, the median diameter is 50% of the integrated particle size distribution curve based on volume.

Next, an operation example of this exhaust gas treatment system will be described.
First, the blower 28 is operated with the inlet valve 22 and the outlet valve 32 of each of the exhaust gas treatment devices 14a to 14d open and the return line valve 48 closed, and the exhaust gas treatment devices 14a to 14d process the exhaust gas. Spent gas is discharged from the outlet duct 32. At this time, as a predetermined concentration of the gas concentration detected by the exhaust gas treatment capacity detection means (gas detector) 42 of each of the exhaust gas treatment devices 14a to 14d, for example, the untreated CF ₄ concentration, for example, 50 ppm or less of the first specified value, for example. If so, the operation of each of the exhaust gas treatment devices 14a to 14d is continued.

For example, when the gas concentration detected by the exhaust gas treatment capacity detection means (gas detector) 42 of one exhaust gas treatment device 14a, for example, the CF ₄ concentration reaches, for example, the first specified value of 50 ppm or more, It was determined that the processing performance of the processing agent 70 in the exhaust gas processing device 14a had deteriorated, and a signal for processing agent replacement was issued. However, there is still the ability to decompose the PFC gas or the like of the treatment agent 70 of the exhaust gas treatment device 14a, and it is desirable to use the treatment agent capacity as much as possible in consideration of operating costs.

Thus, in this way, for example, the predetermined concentration of the gas concentration detected by the exhaust gas treatment capacity detection means (gas detector) 42 of the exhaust gas processing device 14a, for example, the CF ₄ concentration, reaches, for example, the first specified value of 50 ppm or more. When this occurs, the outlet valve 44 of the processed gas discharge line 24 of the exhaust gas processing device 14a is closed to prevent the processed gas processed by the exhaust gas processing device 14a from flowing into the outlet duct 32, and at the same time the return line valve 48 And the blower 50 is operated to return the processed gas processed by the exhaust gas processing device 14 a to the common inlet duct 30 through the processed gas return line 46. In this case, the treatment agent 70 of the exhaust gas treatment device 14a still has the ability to decompose PFC gas or the like even if the treatment performance is reduced. In this way, the exhaust gas having a high PFC gas concentration that has been treated is returned to the common inlet duct 30 without flowing to the outlet duct 32 side, and is reprocessed by the exhaust gas treatment devices 14b to 14d including the exhaust gas treatment device 14a. The processing capability of the processing agent 70 of the processing apparatus 14a can be used up.

For example, when the gas concentration detected by the exhaust gas treatment capacity detection means (gas detector) 42 of the exhaust gas treatment device 14a, for example, a predetermined concentration of CF ₄ concentration, for example, reaches a second specified value of 200 ppm or more, Assuming that the treatment agent 70 in the treatment tank 40 of the exhaust gas treatment device 14a has completely broken through, the inlet valve 22 of the exhaust gas treatment device 14a is closed to stop the inflow of exhaust gas into the exhaust gas treatment device 14a. The signal which should replace the processing tank 40 of 14a is sent. Then, the return line valve 48 of the treated gas return line 46 of the exhaust gas treatment device 14a is closed, and the treatment tank 40 of the exhaust gas treatment device 14a is replaced.

  When the inlet valve 22 is closed and the flow of new untreated exhaust gas into the exhaust gas treatment device 14a is stopped, a signal for cooling down the exhaust gas treatment device 14a is sent. In that case, the rotational speed of the blowers 28 of the other exhaust gas treatment devices 14b to 14d connected to the common inlet duct 30 is increased to increase the exhaust gas treatment amount per exhaust gas treatment device. When the replacement of the treatment tank 40 of the exhaust gas treatment device 14a is completed and the information that the inlet valve 22 of the exhaust gas treatment device 14a is opened is obtained, the rotational speed of the blower 28 in all the exhaust gas treatment devices 14a to 14d is equalized again.

  Next, control of the rotational speed of the blower 28 of each exhaust gas treatment apparatus 14a-14d is demonstrated. Based on the fluctuation of the duct pressure gauge 52 provided in the centralized exhaust duct (common inlet duct) 30, the rotational speed of the blower 28 of each exhaust gas treatment device 14a-14d is controlled. For example, if the pressure in the common inlet duct 30 increases, the rotational speed of the blower 28 of each exhaust gas treatment device 14a-14d is increased, and conversely, if the pressure in the common inlet duct 30 decreases, each exhaust gas treatment device 14a- The rotational speed of the blower 28 of 14d is reduced. In this case, it is preferable to control each blower 28 to the same rotational speed in order to make the processing amount in each exhaust gas processing apparatus 14a-14d uniform.

  For example, as shown in FIG. 3, when four exhaust gas treatment devices 14 a to 14 d are connected to the common inlet duct 30, if the pressure in the common inlet duct 30 is extremely reduced, the four exhaust gas treatment devices 14 a to 14 d are used. One exhaust gas treatment device 14c in 14d, or as shown in FIG. 3, the inlet valves 22 of the two exhaust gas treatment devices 14c and 14d are closed, and the one exhaust gas treatment device 14c or two exhaust gases. The operation of the processing devices 14c and 14d may be stopped. Thus, for example, if the operation of the two exhaust gas treatment devices 14c and 14d is stopped, the exhaust gas can be processed by the operation of the other two exhaust gas treatment devices 14a and 14b. Can be saved without consuming excessive driving force and power.

  The flow control to each exhaust gas treatment device can be performed by controlling the blower rotation speed by measuring the pressure with a pressure gauge, or by controlling the blower rotation speed by measuring the flow rate with a flow meter. Is generally vulnerable to pressure loss and product adhesion / corrosion. For this reason, when measuring on the upstream side of the exhaust gas treatment apparatus, it is desirable to measure the pressure using a pressure gauge.

  In this example, the control units 54 of the plurality of exhaust gas treatment apparatuses 14a to 14d are connected to the centralized control panel 56 so that the control of each device of the plurality of exhaust gas treatment apparatuses 14a to 14d is centrally managed.

  Further, the central control panel 56 and the service support base computer 60 are connected by a LAN transmission cable 58, and the data from the central control panel 56 is transmitted to the service support base computer 60, thereby operating the exhaust gas treatment apparatuses 14a to 14d. Are managed by the computer 60 at the service support base. Thereby, unified management of a processing tank, preparation of a timely alternative processing tank, and prediction of a failure can be enabled.

  FIG. 6 shows an exhaust gas treatment system according to another embodiment of the present invention. The example shown in FIG. 6 differs from the example shown in FIG. 3 in that each exhaust gas treatment device 14a-14d is not provided with a control unit 54 (see FIG. 3), and each exhaust gas treatment device 14a-14d has its respective sensors and valves. Are directly connected to the centralized control panel 56 for control. In FIG. 6, only the sensors and valves of the exhaust gas treatment device 14 a are connected to the central control panel 56, but the sensors and valves of other exhaust gas treatment devices 14 b to 14 d are also connected to the central control panel 56. Has been. The same applies to FIG.

  When the centralized control panel 56 is made independent as described above, the exhaust gas treatment devices 14a to 14d and the centralized control panel 56 can be handled as modules, respectively, so that the number of exhaust gas treatment devices can be increased or decreased, and the treatment process for each exhaust gas treatment device can be different. Even so, it is possible to easily cope with the increase or decrease of the connection. That is, in the example shown in FIG. 3, it is necessary to adjust the control unit 54 and the central control panel 56 of each exhaust gas treatment device 14a to 14d, but in the example shown in FIG. 6, each exhaust gas treatment device 14a to 14d is adjusted. Data from each sensor and driving equipment can be directly controlled by the centralized control panel 56.

FIG. 7 shows an exhaust gas treatment system of still another embodiment of the present invention. This example is different from the example shown in FIG. 3 in that it includes a dilution gas supply line 92 for supplying a dilution gas such as N ₂ gas upstream of the vacuum pump 12 to the exhaust gas of each of the exhaust gas treatment devices 14a to 14d. A treated gas return line 46 branched from the treated gas outflow line 24 is joined to the dilution gas supply line 92, and the treated gas passing through the treated gas return line 46 is fed from the upstream side of the vacuum pump 12 to the common inlet duct. The point is that it is set back to 30. In the drawing, the dilution gas supply line 92 is described only in the exhaust gas treatment device 14d. However, the other exhaust gas treatment devices 14a to 14c are also provided with the dilution gas supply line 92. The treated gas return lines 46 of the exhaust gas treatment devices 14a to 14d are joined together.

  PFC gas is not corrosive gas, and even if corrosive gas is included in the exhaust gas, since it passes through the treatment tank 40 once, most of the corrosive gas in the treated gas is removed. . For this reason, even if it uses processed gas as gas for dilution, there is no problem.

In order to operate the vacuum pump 12, N ₂ gas or the like as a dilution gas is allowed to flow into the vacuum pump 12, and the treated gas return line 42 is connected to the upstream side of the vacuum pump 12, so that N _The amount of the diluting gas such as ₂ gas used can be reduced and the running cost can be reduced.

  FIG. 8 shows an exhaust gas treatment system of still another embodiment of the present invention. This example is different from the example shown in FIG. 6 in that the exhaust gas inflow line of each exhaust gas treatment device 14 is provided without providing the vacuum pump 12 (see FIG. 6) that sends the exhaust gas discharged from the treatment device 10 to the common inlet duct 30. The vacuum pump 12 is installed at 18 and the vacuum pump 12 and the exhaust gas treatment device 14 are integrated. Thus, the present invention can also be applied to a vacuum pump integrated exhaust gas treatment apparatus.

  The preferred embodiments of the present invention have been described above, but the present invention is not limited to the above-described embodiments, and it goes without saying that the present invention may be implemented in various forms within the scope of the technical idea.

DESCRIPTION OF SYMBOLS 10 Manufacturing apparatus 12 Vacuum pump 14a-14d Exhaust gas processing apparatus 18 Exhaust gas inflow line 22 Inlet valve 24 Processed gas outflow line 28,50,80,88 Blower 30 Common inlet duct 32 Outlet duct 40 Treatment tank 42 Exhaust gas processing capacity detection means ( Gas detector)
44 Outlet valve 46 Processed gas return line 48 Return line valve 50 Blower 52 Duct pressure gauge 54 Control unit 56 Central control panel (central control unit)
58 LAN transmission cable 62 heat exchanger 64 heater 66 heater chamber 68 treatment agent filling chamber 70 treatment agent 76 heat insulating material 78, 86 circulation valves 82, 84 circulation piping

Claims (7)

A plurality of exhaust gas treatment devices each provided with a treatment tank; a common inlet duct into which exhaust gas supplied to the plurality of exhaust gas treatment devices flows; an outlet duct for discharging treated gas treated by the exhaust gas treatment device; An exhaust gas treatment system comprising a central control unit for controlling the operating conditions of each exhaust gas treatment device,
Means for detecting the exhaust gas treatment capacity of each exhaust gas treatment device installed downstream of each exhaust gas treatment device;
An outlet valve installed in each treated gas outflow line extending from each exhaust gas treatment device and leading to the outlet duct;
An exhaust gas treatment system comprising a treated gas return line branched from the treated gas outlet line upstream of the outlet valve and joined to the common inlet duct.   The common inlet duct is provided with a duct pressure gauge for detecting the pressure in the common inlet duct, and the central control unit is supplied to each exhaust gas treatment device based on the pressure measured by the duct pressure gauge. The exhaust gas treatment system according to claim 1, wherein the exhaust gas flow rate is controlled.   The exhaust gas treatment system according to claim 1 or 2, wherein the central control unit and a service support base are connected by a LAN. A plurality of exhaust gas treatment devices each provided with a treatment tank; a common inlet duct into which exhaust gas supplied to the plurality of exhaust gas treatment devices flows; an outlet duct for discharging treated gas treated by the exhaust gas treatment device; An operation method of an exhaust gas treatment system including a central control unit that controls the operation conditions of each exhaust gas treatment device,
Each exhaust gas treatment capacity is detected by an exhaust gas treatment capacity detection means installed downstream of each exhaust gas treatment device,
When the exhaust gas treatment capability of one of the plurality of exhaust gas treatment devices exceeds a first predetermined level, the treated gas treated by the one exhaust gas treatment device is caused to flow to the outlet duct. And operating the exhaust gas treatment system by returning to the common inlet duct.   When the exhaust gas treatment capability of one of the plurality of exhaust gas treatment devices exceeds a second predetermined level, the flow of the exhaust gas to the one exhaust gas treatment device is stopped, and the one exhaust gas treatment 5. The operation method of an exhaust gas treatment system according to claim 4, wherein a signal for exchanging the treatment tank provided in the apparatus is issued.   6. The pressure in the common inlet duct is detected by a duct pressure gauge, and the flow rate of exhaust gas supplied to each exhaust gas treatment device is controlled based on the pressure measured by the duct pressure gauge. A method for operating the exhaust gas treatment system according to 1.   The operation method of the exhaust gas treatment system according to any one of claims 4 to 6, wherein data from the central control unit is transmitted to a service support base through a LAN.

Images