JP2018141637A - Sampling system for process fluid - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a technique for sampling a process fluid while maintaining process conditions and safely.SOLUTION: A sampling system comprises: a process fluid supply line 10; a first flow path 20 provided in an upstream portion of the supply line 10; a second flow path 30 provided in a downstream portion; a bypass flow path 40 provided between the first flow path 20 and the second flow path 30; a sampling container 50 capable of connecting the fluid introduction section and the fluid discharge section to both end portions of the bypass flow path 40; an inert gas supply line 60 connected on the path of the first flow path 20; an exhaust gas line 70 connected on the path of the second flow path 30; a first opening/closing valve 25 provided between the upstream portion of the supply line 10 and the connection portion of the inert gas supply line 60; a second opening/closing valve 35 provided between the downstream portion of the supply line 10 and the connecting portion of the exhaust gas line 70; a third on-off valve 65 provided on the inert gas supply line; and a fourth opening/closing valve 75 provided on the exhaust gas line.SELECTED DRAWING: Figure 1B

Description

  The present invention relates to a process fluid sampling system, and more particularly to a technique for safely sampling a liquid or gas containing a substance that easily reacts with oxygen or moisture in the air while maintaining the process conditions.

A fluid (liquid or gas) containing a substance that easily reacts with oxygen or moisture in the air is applied to various applications. For example, a gas containing chlorosilanes or hydrogenated silanes is used as a raw material gas for crystal growth by MOCVD in a semiconductor device manufacturing process. Substances with extremely high reactivity, such as water-inhibiting substances and flammable substances, are usually supplied as liquids or gases. Such a fluid is used in a high-purity state or used with an inert gas such as Ar, He, or N _{2 in} order to prevent reaction with oxygen or moisture in the process.

  Such a fluid is often sampled for process control, quality control, and condition control of the process. Conventionally, for example, the following method has been used for sampling such a process fluid.

  As an example, first, the atmosphere of the sampling environment in which the glove box is installed is replaced with an inert gas or the like. In this state, the sampling pipe is drawn from the process line, and the process fluid is collected in the glove box. Then, the fluid remaining in the process pipe after collecting the process fluid is discarded into the exhaust gas / waste liquid system. In this method, the concentration of oxygen and air in the glove box can be controlled to some extent, but since it is handled in an environment that is open in the glove box, it is not possible to exclude contamination of impurities in the sample. Examples of such a glove box include those disclosed in JP-A-8-192384 (Patent Document 1) and JP-A-2005-81452 (Patent Document 2). The box must be expensive because of its large construction.

  As another example, there is a method using a suction device having a plunger (see, for example, US Pat. No. 6,357,306 (Patent Document 3)). The method installs an aspirator device with a plunger directly in the process line. In addition to the complicated structure of this device, the plunger part after collecting the process fluid is released to the atmosphere, so liquids and gases that contain substances that easily react with oxygen, moisture, etc. in the air are sampled. Not suitable for.

  As another example, there is a method in which a sampling container is depressurized with a vacuum pump or the like, and a necessary sample amount is drawn from a process device or piping. In this method, the inside of the sampling container is preliminarily replaced with an inert gas, and then the pressure is reduced by a vacuum pump. If this method is repeated when a liquid or gas containing a substance that easily reacts with oxygen, moisture, etc. in the air is sampled, the fluid taken in the vacuum pump accumulates and there is a risk of ignition, etc. .

  As yet another example, a method using a so-called Stub Sampler is known. This device is a device that collects a sample in a predetermined metal container or sampling bottle directly from a nozzle or the like for process piping, equipment, containers, tanks, and the like. For example, Japanese Patent Laying-Open No. 2005-083770 (Patent Document 4) discloses such a sampling system. The biggest drawback of this apparatus is that it is necessary to create an inert gas atmosphere in the apparatus when collecting a liquid or gas containing a substance that easily reacts with oxygen or moisture in the air.

JP-A-8-192384 JP 2005-81452 A US Pat. No. 6,357,306 Japanese Patent Laying-Open No. 2005-083770

  As described above, the conventional technique is insufficient from the viewpoint of safely sampling a liquid or a gas containing a substance that easily reacts with oxygen, moisture, or the like in the air while maintaining the process conditions. .

  In view of such problems, the present invention provides a technique for safely sampling a liquid or a gas containing a substance that easily reacts with oxygen or moisture in the air while maintaining the process conditions. It is an object.

  In order to solve the above-mentioned problems, a process fluid sampling system according to the present invention includes a process fluid supply line, a first flow path provided in an upstream portion of the supply line, and a downstream portion of the supply line. A second flow path provided, a bypass flow path provided between the first flow path and the second flow path, and a fluid introduction section and a fluid discharge section can be connected to both ends of the bypass flow path. A sampling vessel, an inert gas supply line connected on the path of the first flow path, an exhaust gas line connected on the path of the second flow path, an upstream portion of the supply line, and the inert gas A first opening / closing valve provided between a connection part of the supply line, a second opening / closing valve provided between a downstream part of the supply line and the connection part of the exhaust gas line, and the inert gas supply line Third open / close valve provided above A fourth open / close valve provided on the exhaust gas line, and the sampling container is provided with a fifth open / close valve provided upstream of the bypass flow path and a downstream part of the bypass flow path. The sixth open / close valve is provided.

  In a preferred embodiment, the gas from the inert gas supply line is placed on the first flow path between the third on-off valve and the first on-off valve and in the immediate vicinity of the first on-off valve. 1 It has a gas passage that leads to the open / close valve side.

  In a preferred embodiment, the gas from the inert gas supply line is on the second flow path between the second open / close valve and the fourth open / close valve and in the immediate vicinity of the second open / close valve. A gas passage portion that leads to the fourth on-off valve side is provided.

  In a preferred embodiment, the gas from the inert gas supply line is disposed on the first flow path between the third open / close valve and the fifth open / close valve and in the immediate vicinity of the fifth open / close valve. A gas path portion that leads to the fifth on-off valve side is provided.

  In a preferred aspect, the gas from the inert gas supply line is placed on the bypass flow path between the fifth open / close valve and the sixth open / close valve and in the immediate vicinity of the sixth open / close valve. A gas path portion that leads to the sixth opening / closing valve side is provided.

  Further, in a preferred aspect, when the sampling container is not connected to both ends of the bypass flow path, a closing valve for bypassing the fluid from the first flow path to the second flow path in the bypass flow path It has.

  According to the present invention, it is possible to collect a liquid or a gas containing a substance that easily reacts with oxygen or moisture in the air while maintaining the process conditions. Further, since it is not necessary to open part of the system to the atmosphere, safe sampling is possible. That is, the present invention provides a technique for safely sampling a liquid or a gas containing a substance that easily reacts with oxygen, moisture, or the like in the air while maintaining the process conditions.

It is a block diagram which shows an example of the sampling system (at the time of sampling container non-connection) of the process fluid which concerns on this invention. It is a block diagram which shows an example of the sampling system (at the time of sampling container connection) of the process fluid which concerns on this invention. A mode (a) including a gas path portion for guiding gas from the inert gas supply line to the first opening / closing valve side, and a gas path portion for guiding gas from the inert gas supply line to the fourth opening / closing valve side It is a figure which shows the aspect (b) with which it is equipped. It is a block diagram which shows an example of the sampling system (at the time of sampling container non-connecting) of the process fluid based on this invention comprised as a structure provided with the (supply) line of another process fluid other than the (supply) line of a process fluid. It is a block diagram which shows an example of the sampling system (at the time of sampling container non-connecting) of the process fluid based on this invention comprised as a structure provided with the (supply) line of another process fluid other than the (supply) line of process fluid. 3B is a block diagram illustrating an example of an aspect in which a seventh opening / closing valve is provided in a path between a fifth opening / closing valve and a sixth opening / closing valve in the aspect illustrated in FIG. 3B. FIG.

  A process fluid sampling system according to the present invention will be described below with reference to the drawings.

  In order to monitor the state of process fluids (liquids and gases) containing substances that easily react with oxygen, moisture, etc. in the air, not only sampling with oxygen and moisture completely shut off, but also impurities during collection It is necessary to devise so as not to mix.

  1A and 1B are block diagrams showing an example of a process fluid sampling system developed as a result of intensive studies by the present inventors. FIG. 1A is a state in which the sampling container is not connected, and FIG. 1B is a state in which the sampling container is connected. FIG.

  In this figure, reference numeral 10 denotes a process fluid (supply) line, reference numeral 20 denotes a first flow path provided upstream of the (supply) line 10, and reference numeral 30 denotes a downstream part of the (supply) line 10. It is the 2nd flow path provided in. A bypass channel 40 is provided between the first channel 20 and the second channel 30. A gas line (inert gas supply line) 60 for supplying an inert gas such as nitrogen is provided on the path of the first flow path 20, and exhaust gas is discharged to the outside on the path of the second flow path 30. A gas line (exhaust gas line) 70 is provided. Further, between the upstream part of the process fluid supply line 10 and the connection part of the inert gas supply line 60, the first on-off valve 25, between the downstream part of the supply line 10 and the connection part of the exhaust gas line 70 are provided. The second opening / closing valve 35, the inert gas supply line 60 is provided with a third opening / closing valve 65, and the exhaust gas line 70 is provided with a fourth opening / closing valve 75. The block diagram shown in this figure shows a state in which the sampling container is not connected, so that the connection portions 40a and 40b with the sampling container located at both ends of the bypass channel 40 are sealed. These connection portions 40a and 40b may be configured to include a closing valve that bypasses the process fluid from the first flow path 20 to the second flow path 30 through the bypass flow path 40.

  FIG. 1B is a diagram showing a state in which the sampling container 50 is connected to the gas line system. The sampling container 50 is a container that can be connected to both ends of the bypass flow path 40 by a fluid introduction part and a fluid discharge part. A fifth opening / closing valve 50a is provided in the fluid introduction part provided in the upstream part of the flow path 40, and a sixth opening / closing valve 50b is provided in the fluid discharge part provided in the downstream part of the bypass flow path 40. .

  That is, the process fluid sampling system shown in these drawings includes a process fluid supply line, a first flow path provided upstream of the supply line, and a first flow path provided downstream of the supply line. Two flow paths, a bypass flow path provided between the first flow path and the second flow path, a sampling container capable of connecting a fluid introduction part and a fluid discharge part to both ends of the bypass flow path, An inert gas supply line connected on the path of the first flow path; and an exhaust gas line connected on the path of the second flow path; and an upstream portion of the supply line and the inert gas A first opening / closing valve is provided between the connection portion of the supply line and a second opening / closing valve is provided between the downstream portion of the supply line and the connection portion of the exhaust gas line. Third open / close on active gas supply line Lube is provided, it is provided with the fourth on-off valve on the exhaust gas line. The sampling container is provided with a fifth open / close valve provided in the upstream portion of the bypass flow path and a sixth open / close valve provided in the downstream portion of the bypass flow path.

  The sampling of the process fluid in the above system is performed by the following procedure. First, when the valve 25 and the valve 35 are in the “closed” state, the process fluid flows through the supply line 10 in a steady state. In this state, an inert gas such as nitrogen is flowed from the inert gas supply line 60 to the first flow path 20, the bypass flow path 40, and the second flow path 30, and the valve 65 and the valve 75 are operated to operate the first flow path. A pressure purge is performed between the flow path 20 and the second flow path 30 so that the pressure between the first flow path 20 and the second flow path 30 is sufficiently higher than that of the process fluid supply line 10.

  In this state, the sampling container 50 is prepared, the valve 65 is set to “slightly open”, the connection portions 40a and 40b are loosened while purging the flow path, and the sampling container 50 is connected. At the time of connection, the valves 50a and 50b of the sampling container 50 are “closed” for the container side and “open” for the bypass flow path 40 side. That is, while the sampling container 50 is connected, the space between the first flow path 20 and the second flow path 30 is always purged with the inert gas.

  After connecting the sampling container 50, the valve 65 and the valve 75 are operated to repeat the pressure purge between the first flow path 20 and the second flow path 30 to clean the flow path.

  Subsequently, the valve 25 and the valve 35 are opened, and the process fluid is guided to the first flow path 20 and returned from the second flow path 30 to the process fluid supply line 10. The flow path between the second flow paths 30 is further cleaned. During this cleaning, the valve 75 is kept “closed” and the process fluid is not discarded.

  After the flow path is sufficiently cleaned, an operation for preventing liquid sealing is performed. Specifically, the valve 25 is “closed” and the valve 65 is “open”, and the process fluid remaining in the bypass flow path 40 is discharged to the second flow path 30 side. The remaining fluid may be discharged from the exhaust gas line 70 by operating the valve 75. After this liquid seal prevention operation, the valve 35 and the valve 75 are closed.

  Subsequently, the pressure purge between the first flow path 20 and the second flow path 30 is stopped by setting the valve 65 to “closed”, the valve 25 is set to “open”, and the stock pressure with the process fluid is performed. “Open”. Then, the valves 50a and 50b of the sampling container 50 are opened to the container side, and sampling of the process fluid into the container 50 is started.

  After sampling a desired amount, the valves 50a and 50b of the sampling container 50 are “closed” with respect to the container side, “open” with respect to the bypass flow path 40 side, and the valves 25 and 35 are “closed”. To do.

  By opening the valve 65 and the valve 75 and flowing an inert gas, the process fluid remaining in the flow path is discharged from the exhaust gas line 70 to the outside of the system.

  After this discharge blow is performed for a predetermined time, the sampling container is opened while the valve 65 is slightly opened to purge the flow path between the first flow path 20 and the second flow path 30 while ventilating the inert gas. 50 is disconnected from the flow path and returned to the state shown in FIG. 1A.

  After the separation of the sampling container 50 from the flow path, an inert gas supply from the inert gas supply line 60 causes the flow path between the first flow path 20 and the second flow path 30 to flow through the process fluid. The positive pressure is slightly higher than that of the supply line 10.

  In the present invention, as shown in FIG. 2A, on the path of the first flow path 20 between the third on-off valve 65 and the first on-off valve 25 and in the immediate vicinity of the first on-off valve 25, It is preferable to include a gas path portion 80a that guides the gas from the inert gas supply line 60 to the first opening / closing valve 25 side.

  Similarly, as illustrated in FIG. 2B, on the path of the second flow path 30 between the second opening / closing valve 35 and the fourth opening / closing valve 75 and in the immediate vicinity of the second opening / closing valve 35, It is preferable to include a gas path portion 80b that guides the gas from the active gas supply line 60 to the fourth opening / closing valve 75 side.

  By providing such a gas path portion, purging of the gas flow path can be made more reliable, and contamination of impurities and the like can be suppressed.

  Although not shown, in the same manner as the gas path portions 80a and 80b described above, on the path of the first flow path 20 between the third on-off valve 65 and the fifth on-off valve 50a and in the immediate vicinity of the fifth on-off valve 50a. In addition, it is preferable that a gas path portion for guiding the gas from the inert gas supply line 60 to the fifth opening / closing valve 50a side is provided, and the bypass flow path 40 between the fifth opening / closing valve 50a and the sixth opening / closing valve 50b. It is preferable that a gas path portion for guiding the gas from the inert gas supply line 60 to the sixth opening / closing valve 50b side is provided in the vicinity of the sixth opening / closing valve 50b.

  Further, in addition to the process fluid (supply) line 10 described above, another process fluid (supply) line 11 may be provided. Appropriately selected in consideration of sampling level and other circumstances.

  FIGS. 3A and 3B are block diagrams showing an example in which, in the embodiment shown in FIGS. 1A and 1B, another process fluid (supply) line 11 is provided in addition to the process fluid (supply) line 10. It is. In the examples shown in these drawings, the process fluid (supply) line 10 is connected to the first flow path 20, and the other process fluid (supply) lines 11 are connected to the second flow path 30. . That is, when referring to the “process fluid supply line” in the present invention, this flow path does not have to be a single (supply) line, and may be composed of a plurality of (supply) lines.

  3B, when the open / close valve of the sampling container 50 is not a three-way valve but a two-way valve, the path between the fifth open / close valve 50a and the sixth open / close valve 50b described above. Alternatively, a seventh opening / closing valve 50c may be provided.

  FIG. 4 is a block diagram showing an example of an aspect in which a seventh opening / closing valve 50c is provided in the path between the fifth opening / closing valve 50a and the sixth opening / closing valve 50b in the aspect shown in FIG. 3B. By setting it as such an aspect, even if the opening-and-closing valve of the sampling container 50 is a two-way valve, the handling similar to the case where it is a three-way valve is actually attained. 4 (a) and 4 (b) respectively show a gas path portion 81a provided between the fifth on-off valve 50a and the seventh on-off valve 50c, and the seventh on-off valve 50c and the sixth on-off valve. It is a figure which shows the gas path part 81b provided between these opening-and-closing valves 50b, It is preferable to provide such gas path part 81a, 81b.

  The present invention provides a technique for safely sampling a liquid or a gas containing a substance that easily reacts with oxygen or moisture in the air while maintaining the process conditions.

100 Process Fluid Sampling System 10, 11 Process Fluid (Supply) Line 20 First Flow Path 25 First Open / Close Valve 30 Second Flow Path 35 Second Open / Close Valve 40 Bypass Flow Path 40a, 40b Connection to Sampling Container Part 50 Sampling container 50a Fifth on-off valve 50b Sixth on-off valve 50c Seventh on-off valve 60 Inert gas supply line 65 Third on-off valve 70 Exhaust gas line 75 Fourth on-off valve 80a, 80b, 81a, 81b Gas path

Claims (6)

A process fluid supply line;
A first flow path provided upstream of the supply line;
A second flow path provided in a downstream portion of the supply line;
A bypass flow path provided between the first flow path and the second flow path;
A sampling container capable of connecting a fluid introduction part and a fluid discharge part to both ends of the bypass flow path;
An inert gas supply line connected on the path of the first flow path;
An exhaust gas line connected on the path of the second flow path;
A first on-off valve provided between an upstream portion of the supply line and a connection portion of the inert gas supply line;
A second on-off valve provided between a downstream part of the supply line and a connection part of the exhaust gas line;
A third on-off valve provided on the inert gas supply line;
A fourth on-off valve provided on the exhaust gas line,
The sampling container is provided with a fifth open / close valve provided in the upstream portion of the bypass flow path and a sixth open / close valve provided in the downstream portion of the bypass flow path,
Process fluid sampling system.   The gas from the inert gas supply line is disposed on the first opening / closing valve side on the first flow path between the third opening / closing valve and the first opening / closing valve and in the immediate vicinity of the first opening / closing valve. The process fluid sampling system of claim 1, further comprising a gas path leading to   The gas from the inert gas supply line is disposed on the side of the fourth on-off valve on the second flow path between the second on-off valve and the fourth on-off valve and in the immediate vicinity of the second on-off valve. The process fluid sampling system of claim 1, further comprising a gas path leading to   The gas from the inert gas supply line is placed on the side of the fifth opening / closing valve on the first flow path between the third opening / closing valve and the fifth opening / closing valve and in the immediate vicinity of the fifth opening / closing valve. The process fluid sampling system of claim 1, further comprising a gas path leading to   The gas from the inert gas supply line is moved to the sixth opening / closing valve side on the bypass flow path between the fifth opening / closing valve and the sixth opening / closing valve and in the immediate vicinity of the sixth opening / closing valve. The process fluid sampling system of claim 1, comprising a gas path leading.   A closing valve is provided at both ends of the bypass flow path to bypass the fluid in the bypass flow path from the first flow path to the second flow path when the sampling container is disconnected. Item 4. The process fluid sampling system according to Item 1.