JP2022060043A - Microorganism measuring method and microorganism measuring device - Google Patents

Abstract

To accurately measure microorganisms contained in a compressed gas.SOLUTION: In a microorganism measuring device 10, microorganisms contained in compressed air are captured by allowing the compressed air introduced from a measurement passage 12 into a membrane holder 18 to pass through a membrane filter 19 held in the membrane holder 18. According to this, microorganisms contained in the compressed air can be measured accurately, since microorganisms can be captured by the membrane filter 19 by directly contacting the compressed air containing microorganisms with the membrane filter 19.SELECTED DRAWING: Figure 1

Description

The present invention relates to a microorganism measuring method for measuring microorganisms contained in a compressed gas, and a microorganism measuring device.

For example, compressed gas such as compressed air used in factories may contain microorganisms such as bacteria and mold. Therefore, conventionally, the measurement of microorganisms contained in the compressed gas has been performed. As a method for measuring microorganisms, first, as in Patent Document 1, for example, by sending a compressed gas into an impinger containing pure water, the microorganisms contained in the compressed gas are made of pure water. Collect bubbling water. Subsequently, for example, as in Patent Document 2, a predetermined amount of the sample liquid in which the microorganism is collected is filtered by the membrane filter, and the microorganism is captured by the membrane filter. Then, the microorganisms captured by the membrane filter are stained with a fluorescent dye, laser light is irradiated toward the membrane filter, and the membrane filter is imaged by an imaging unit such as a CCD camera. As a result, if the microorganism is captured by the membrane filter, the image pickup unit captures the image of the microorganism stained with the fluorescent dye as a light emitting point, so that the microorganism captured by the membrane filter can be measured. Therefore, it is possible to measure the microorganisms contained in the compressed gas.

Japanese Patent No. 65166662 JP-A-2019-136023

However, the pure water contained in the impinger may contain microorganisms even before the compressed gas is sent into the impinger. In this case, the microorganisms contained in the compressed gas are captured by the membrane filter together with the microorganisms contained in the pure water before the compressed gas is sent into the impinger, so that they are captured by the membrane filter. Even if the microorganisms contained in the compressed gas are measured, it is possible that the microorganisms contained in the compressed gas cannot be accurately measured. Therefore, there is a possibility that the microorganisms contained in the compressed gas cannot be measured accurately.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a microorganism measuring method and a microorganism measuring device capable of accurately measuring microorganisms contained in a compressed gas. It is in.

In the microorganism measurement method for solving the above problems, a part of the compressed gas flowing through the main passage is allowed to flow through the measurement passage branched from the main passage through which the compressed gas containing microorganisms flows, and the compression discharged from the measurement passage is performed. After the gas introduction step of introducing the gas into the tubular membrane holder and the compression introduced into the membrane holder from the measurement passage with respect to the membrane filter held in the membrane holder after the gas introduction step. A microorganism capture step of passing a gas to capture the microorganisms contained in the compressed gas, a fluorescent dyeing step of dyeing a fluorescent dye on the microorganisms captured by the membrane filter after the microorganism capture step, and the fluorescence. After the dyeing step, a microorganism measurement step of measuring the microorganisms trapped in the membrane filter is performed.

In the above-mentioned microorganism measurement method, the compressed gas introduced into the membrane holder is depressurized by a flow rate adjusting unit provided at a portion upstream of the membrane holder in the measurement passage, and the flow rate of the compressed gas is predetermined. It is advisable to adjust the flow rate below the specified flow rate.

The microorganism measuring device that solves the above-mentioned problems is branched from the main passage through which the compressed gas containing microorganisms flows, and at the same time, the measuring passage through which a part of the compressed gas flowing through the main passage flows and the compression discharged from the measuring passage. A tubular membrane holder into which gas is introduced, a membrane filter that captures microorganisms held in the membrane holder and contained in the compressed gas introduced into the membrane holder, and microorganisms captured in the membrane filter. It is equipped with a microorganism measuring unit for measuring.

In the above-mentioned microorganism measuring apparatus, it is preferable that a flow rate adjusting portion is provided at a portion upstream of the membrane holder in the measuring passage.

According to the present invention, microorganisms contained in the compressed gas can be accurately measured.

The schematic diagram for demonstrating the microorganism measuring apparatus in an embodiment. Exploded view of the membrane holder and membrane filter. A flowchart for explaining a microorganism measurement method.

Hereinafter, an embodiment in which the microorganism measuring method and the microorganism measuring device are embodied will be described with reference to FIGS. 1 to 3. The microorganism measuring method and the microorganism measuring device of the present embodiment are used for measuring the microorganisms contained in the compressed gas used in the factory. In factories, for example, compressed air is used as the compressed gas. Further, the "microorganism" is, for example, a bacterium, a virus, a mold or the like.

As shown in FIG. 1, the microorganism measuring device 10 includes a measuring passage 12 branched from a main passage 11 provided in the factory. The main passage 11 is, for example, a pipe through which compressed air containing microorganisms flows. A compressor 13, which is a source of compressed air, is connected to the main passage 11. Compressed air discharged from the compressor 13 flows through the main passage 11. A part of the compressed air flowing through the main passage 11 flows through the measurement passage 12.

The microorganism measuring device 10 includes a regulator 14, a pressure gauge 15, a variable diaphragm 16, a flow meter 17, and a tubular membrane holder 18. The measurement passage 12 has a first pipe 21, a second pipe 22, a third pipe 23, and a fourth pipe 24. Further, the passage in the regulator 14, the passage in the variable throttle 16, and the passage in the flow meter 17 form a part of the measurement passage 12.

The first pipe 21 connects the main passage 11 and the regulator 14. One end of the first pipe 21 is connected in the middle of the main passage 11. The other end of the first pipe 21 is connected to the inlet 14a of the regulator 14. The second pipe 22 connects the regulator 14 and the variable diaphragm 16. One end of the second pipe 22 is connected to the outlet 14b of the regulator 14. The other end of the second pipe 22 is connected to the inlet 16a of the variable throttle 16. The third pipe 23 connects the variable throttle 16 and the flow meter 17. One end of the third pipe 23 is connected to the outlet 16b of the variable throttle 16. The other end of the third pipe 23 is connected to the inlet 17a of the flow meter 17. The fourth pipe 24 connects the flow meter 17 and the membrane holder 18. One end of the fourth pipe 24 is connected to the outlet 17b of the flow meter 17. The other end of the fourth pipe 24 is connected to the introduction port 18a of the membrane holder 18.

The regulator 14 adjusts the pressure of the compressed air supplied from the main passage 11 to the regulator 14 through the first pipe 21 and the inlet 14a of the regulator 14 to a predetermined pressure. Therefore, the regulator 14 adjusts the pressure of the compressed air flowing through the measurement passage 12 to a predetermined pressure.

The variable throttle 16 flows out from the outlet 14b of the regulator 14 to the second pipe 22, decompresses the compressed air supplied to the variable throttle 16 through the second pipe 22 and the inlet 16a of the variable throttle 16, and the flow rate of the compressed air. Is adjusted to a predetermined flow rate or less, and then discharged from the outlet 16b of the variable throttle 16. Therefore, the variable throttle 16 decompresses the compressed air flowing through the measurement passage 12 and adjusts the flow rate of the compressed air to a predetermined flow rate or less.

The variable diaphragm 16 is a flow rate adjusting unit provided in a portion upstream of the membrane holder 18 in the measurement passage 12. Therefore, in the microorganism measuring device 10 of the present embodiment, a variable diaphragm 16 as a flow rate adjusting unit is provided at a portion upstream of the membrane holder 18 in the measuring passage 12.

The flow meter 17 detects the flow rate of compressed air discharged from the outlet 16b of the variable throttle 16 and supplied to the flow meter 17 through the third pipe 23 and the inlet 17a of the flow meter 17. Therefore, the flow meter 17 detects the flow rate of the compressed air flowing through the measurement passage 12 after the flow rate is adjusted by the variable throttle 16. The compressed air flowing out from the outlet 17b of the flow meter 17 to the fourth pipe 24 is introduced into the membrane holder 18 via the introduction port 18a of the fourth pipe 24 and the membrane holder 18. Therefore, the compressed air discharged from the measurement passage 12 is introduced into the membrane holder 18. Therefore, in the microorganism measuring device 10 of the present embodiment, the flow rate of the compressed air introduced into the membrane holder 18 is adjusted to a predetermined flow rate or less by the variable throttle 16.

The measurement passage 12 has a pressure detection pipe 25. The pressure detection pipe 25 is connected to a portion of the measurement passage 12 between the regulator 14 and the variable throttle 16. Therefore, the pressure detection pipe 25 is connected to the second pipe 22 in a state of being branched from the middle of the second pipe 22. One end of the pressure detection pipe 25 is connected to the second pipe 22. The other end of the pressure detection pipe 25 is connected to the pressure gauge 15.

A part of the compressed air that flows out from the outlet 14b of the regulator 14 to the second pipe 22 and flows through the second pipe 22 flows through the pressure detection pipe 25. The pressure gauge 15 detects the pressure of the compressed air flowing through the pressure detection pipe 25. Therefore, it can be said that the pressure gauge 15 detects the pressure of the compressed air flowing out from the outlet 14b of the regulator 14 and flowing through the second pipe 22. Therefore, the pressure gauge 15 detects the pressure of the compressed air flowing through the measurement passage 12 after the pressure is adjusted by the regulator 14.

The microorganism measuring device 10 includes a control computer 30. The control computer 30 includes a central processing unit (CPU). Further, the control computer 30 includes a memory composed of a read-only memory (ROM) that stores various programs, maps, and the like in advance, a random access memory (RAM) that temporarily stores the calculation results of the CPU, and the like. Further, the control computer 30 includes a timer counter, an input interface, an output interface, and the like.

The control computer 30 is electrically connected to a regulator 14, a pressure gauge 15, a variable throttle 16, and a flow meter 17, respectively. The control computer 30 controls the drive of the regulator 14. Further, the control computer 30 receives information about the pressure detected by the pressure gauge 15. Further, the control computer 30 controls the opening degree of the variable diaphragm 16. Further, the control computer 30 receives information regarding the flow rate detected by the flow meter 17.

The control computer 30 stores in advance a pressure determination program that determines whether or not the pressure detected by the pressure gauge 15 is a predetermined pressure. The control computer 30 stores in advance a control program that controls the drive of the regulator 14 so that the pressure detected by the pressure gauge 15 becomes a predetermined pressure.

The control computer 30 stores in advance a flow rate determination program for determining whether or not the flow rate detected by the flow meter 17 is a predetermined flow rate. The control computer 30 stores in advance a control program that controls the opening degree of the variable throttle 16 so that the flow rate detected by the flow meter 17 becomes a predetermined flow rate.

As shown in FIG. 2, the microorganism measuring device 10 includes a membrane filter 19 held in the membrane holder 18. The membrane holder 18 has a first holder member 41 and a second holder member 42.

The first holder member 41 has a bottomed tubular shape. The first holder member 41 has a first dome portion 41a and a first flange portion 41b projecting outward from the opening of the first dome portion 41a in an annular shape. The first holder member 41 has an introduction pipe 41c. The introduction pipe 41c protrudes from a portion of the first dome portion 41a opposite to the opening. The opening at the tip of the introduction tube 41c is the introduction port 18a of the membrane holder 18.

The second holder member 42 has a bottomed tubular shape. The second holder member 42 has a second dome portion 42a and a second flange portion 42b that projects outward in an annular shape from the opening of the second dome portion 42a. The second holder member 42 has a discharge pipe 42c. The discharge pipe 42c protrudes from a portion of the second dome portion 42a opposite to the opening. The opening at the tip of the discharge pipe 42c is an discharge port 18b that communicates with the outside.

The first holder member 41 and the second holder member 42 are connected to each other with the first flange portion 41b and the second flange portion 42b abutting against each other. The first holder member 41 and the second holder member 42 are fastened to each other by, for example, a plurality of bolts (not shown). The membrane filter 19 is held in the membrane holder 18 with the outer peripheral edge of the membrane filter 19 sandwiched between the first flange portion 41b and the second flange portion 42b. Therefore, the membrane filter 19 is arranged at the boundary portion between the first holder member 41 and the second holder member 42 in the membrane holder 18.

The membrane filter 19 captures microorganisms contained in the compressed air introduced into the membrane holder 18. Specifically, the compressed air introduced into the membrane holder 18 from the introduction port 18a via the introduction pipe 41c flows in the membrane holder 18 toward the discharge pipe 42c. The compressed air passes through the membrane filter 19 while flowing through the membrane holder 18 from the introduction pipe 41c toward the discharge pipe 42c. As a result, the membrane filter 19 captures the microorganisms contained in the compressed air. The compressed air that has passed through the membrane filter 19 passes through the discharge pipe 42c and is discharged to the outside from the discharge port 18b.

As shown in FIG. 1, the microorganism measuring device 10 includes a microorganism measuring unit 50 for measuring microorganisms captured by the membrane filter 19. The microorganism measuring unit 50 has, for example, a fluorescent dyeing unit 51 that stains a fluorescent dye on the microorganisms captured by the membrane filter 19, and an imaging unit 52 that images the membrane filter 19. The fluorescent dyeing unit 51 is configured so that, for example, the fluorescent dye can be dropped into the membrane holder 18 from the introduction tube 41c of the membrane holder 18. The image pickup unit 52 is, for example, a CCD camera or the like.

The control computer 30 is electrically connected to the image pickup unit 52. The control computer 30 receives information about the image captured by the image pickup unit 52. The control computer 30 stores in advance a measurement program for measuring the microorganisms captured by the membrane filter 19 based on the image captured by the image pickup unit 52. For example, the control computer 30 determines in the measurement program whether or not the light emitting point is captured in the image captured by the image pickup unit 52. Then, when the control computer 30 determines in the measurement program that the light emitting point is captured in the image captured by the imaging unit 52, the control computer 30 counts the light emitting point to capture the microorganisms captured by the membrane filter 19. Measure the number of. Therefore, the control computer 30 constitutes a part of the microorganism measuring unit 50.

Next, the operation of this embodiment will be described while explaining the method for measuring microorganisms of this embodiment.
As shown in FIG. 3, first, in step S11, the microorganism measuring device 10 causes a part of the compressed air flowing through the main passage 11 to flow through the measuring passage 12 branched from the main passage 11 through which the compressed air containing the microorganism flows. At the same time, a gas introduction step of introducing the compressed air discharged from the measurement passage 12 into the membrane holder 18 is performed. At this time, the compressed air introduced into the membrane holder 18 is depressurized by the variable flow rate 16 provided at the portion upstream of the membrane holder 18 in the measurement passage 12, and the compressed air introduced into the membrane holder 18 is reduced. The flow rate is adjusted to be less than or equal to the predetermined flow rate.

Next, in step S12, the microorganism measuring device 10 applies compressed air introduced into the membrane holder 18 from the measuring passage 12 to the membrane filter 19 held in the membrane holder 18 after the gas introduction step. A microbial capture step is performed in which the gas is passed through to capture the microorganisms contained in the compressed air. At this time, the compressed air introduced into the membrane holder 18 is depressurized by the variable throttle 16, and the flow rate of the compressed air introduced into the membrane holder 18 is adjusted to be equal to or lower than a predetermined flow rate. Therefore, the membrane filter 19 It is suppressed that the membrane filter 19 is deformed by the compressed air passing through the membrane filter 19. Therefore, the "predetermined flow rate" is a flow rate at which the membrane filter 19 is not deformed even if the compressed air passes through the membrane filter 19, and is obtained in advance by experiments or the like. Specifically, the compressed air introduced into the membrane holder 18 is depressurized to, for example, 50 kPa to 100 kPa by the variable throttle 16. More preferably, the compressed air introduced into the membrane holder 18 is depressurized to 55 kPa to 80 kPa by the variable throttle 16.

Then, in the microorganism capture step, the compressed air passing through the membrane filter 19 is filtered by the membrane filter 19, and the microorganisms are captured by the membrane filter 19. The compressed air that has passed through the membrane filter 19 passes through the discharge pipe 42c and is discharged to the outside from the discharge port 18b.

Subsequently, in step S13, the microorganism measuring apparatus 10 performs a fluorescent dyeing step of dyeing the microorganisms captured by the membrane filter 19 with a fluorescent dye by the fluorescent dyeing unit 51 after the microorganism capture step. Specifically, after the microorganism capture step, the membrane holder 18 is removed from the fourth pipe 24, and the fluorescent dye is dropped from the introduction pipe 41c of the membrane holder 18 into the membrane holder 18 by the fluorescent dyeing unit 51. As a result, the fluorescent dye is dyed against the microorganisms trapped in the membrane filter 19.

Next, in step S14, the microorganism measuring device 10 performs a microorganism measuring step of measuring the microorganisms trapped in the membrane filter 19 after the fluorescent staining step. Specifically, first, after the fluorescent dyeing step, the membrane filter 19 is taken out from the membrane holder 18, and the membrane filter 19 is imaged by the imaging unit 52. Then, the control computer 30 receives the image captured by the image pickup unit 52, and measures the microorganisms captured by the membrane filter 19 based on the received image. The control computer 30 determines whether or not the light emitting point is captured in the image captured by the image pickup unit 52, and if it is determined that the light emitting point is captured in the image, the control computer 30 counts the light emitting point. The counting of emission points performed by the control computer 30 is synonymous with counting the number of microorganisms trapped in the membrane filter 19. In this way, the microorganisms contained in the compressed air are measured by the microorganism measuring device 10.

In the above embodiment, the following effects can be obtained.
(1) In the microorganism measuring device 10, the compressed air introduced into the membrane holder 18 is passed through the measuring passage 12 through the membrane filter 19 held in the membrane holder 18 and is included in the compressed air. Capture microorganisms. According to this, the compressed air containing the microorganisms can be brought into direct contact with the membrane filter 19 and the microorganisms can be captured by the membrane filter 19, so that the microorganisms contained in the compressed air can be measured accurately. Can be done.

(2) In the microorganism measuring device 10, the compressed air introduced into the membrane holder 18 is depressurized by a variable throttle 16 provided at a portion upstream of the membrane holder 18 in the measuring passage 12, and the flow rate of the compressed air is reduced. Adjust to a predetermined flow rate or less. According to this, it is possible to prevent the membrane filter 19 from being deformed by the compressed air passing through the membrane filter 19. Therefore, for example, when the membrane filter 19 is deformed, the deformed portion such as wrinkles generated in the membrane filter 19 is fluorescently stained, so that the control computer 30 erroneously counts the light emitting point as a microorganism. It can be avoided. Therefore, the microorganisms contained in the compressed air can be measured more accurately.

(3) According to the microorganism measuring device 10 of the present embodiment, since the microorganisms contained in the compressed air can be measured with high accuracy, it is possible to measure a small number of microorganisms with high accuracy.

The above embodiment can be modified and implemented as follows. The above embodiment and the following modified examples can be implemented in combination with each other within a technically consistent range.

-In the embodiment, instead of the variable throttle 16, for example, a fixed diaphragm may be adopted as a flow rate adjusting unit. In this case, it is necessary to adjust the opening degree of the fixed throttle in advance so that the flow rate does not deform the membrane filter 19 even if the compressed air passes through the membrane filter 19.

-In the embodiment, instead of the variable throttle 16, for example, an ejector may be adopted as a flow rate adjusting unit.
-In the embodiment, the microorganism measuring device 10 may be configured not to be provided with a flow rate adjusting unit such as a variable diaphragm 16 at a portion upstream of the membrane holder 18 in the measuring passage 12.

-In the embodiment, the specific method of the fluorescent dyeing step of dyeing the fluorescent dye with respect to the microorganisms trapped in the membrane filter 19 after the microorganism trapping step is not particularly limited.

-In the embodiment, the specific method of the microorganism measurement step of measuring the microorganisms trapped in the membrane filter 19 after the fluorescent dyeing step is not particularly limited.
-In the embodiment, the main passage 11 is not limited to the piping provided in the factory. In short, the measurement passage 12 may be branched from the main passage 11 through which the compressed gas containing microorganisms flows, and the specific use of the main passage 11 is not particularly limited.

-In the embodiment, the compressed gas flowing through the main passage 11 is not limited to compressed air, and may be, for example, nitrogen gas or carbon dioxide gas.

10 ... Microorganism measuring device, 11 ... Main passage, 12 ... Measuring passage, 16 ... Variable throttle as flow rate adjusting unit, 18 ... Membrane holder, 19 ... Membrane filter, 50 ... Microorganism measuring unit.

Claims (4)

A part of the compressed gas flowing through the main passage is passed through the measurement passage branched from the main passage through which the compressed gas containing microorganisms flows, and the compressed gas discharged from the measurement passage is introduced into the tubular membrane holder. Gas introduction process and
After the gas introduction step, the compressed gas introduced into the membrane holder is passed through the measurement passage through the membrane filter held in the membrane holder to capture the microorganisms contained in the compressed gas. Microbial capture process and
After the microorganism capture step, a fluorescent dyeing step of dyeing the microorganisms captured by the membrane filter with a fluorescent dye,
A method for measuring microorganisms, wherein after the fluorescent dyeing step, a microorganism measuring step of measuring microorganisms trapped in the membrane filter is performed. The flow rate adjusting unit provided in the portion upstream of the membrane holder in the measurement passage decompresses the compressed gas introduced into the membrane holder, and adjusts the flow rate of the compressed gas to a predetermined flow rate or less. The microorganism measuring method according to claim 1. A measurement passage that is branched from the main passage through which the compressed gas containing microorganisms flows and a part of the compressed gas that flows through the main passage flows.
A cylindrical membrane holder into which the compressed gas discharged from the measurement passage is introduced, and
A membrane filter that is held in the membrane holder and captures microorganisms contained in the compressed gas introduced into the membrane holder.
A microorganism measuring device including a microorganism measuring unit for measuring microorganisms trapped in the membrane filter. The microorganism measuring apparatus according to claim 3, wherein a flow rate adjusting unit is provided at a portion upstream of the membrane holder in the measuring passage.

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