JP2021081388A - Analyzer and method for analysis - Google Patents

Abstract

To provide an inexpensive and small analyzer that can easily analyze a sample by cooling a metal sample and then heating the sample and using a gas that removes while the heating.SOLUTION: A furnace 10 cools down a reactor core tube 20 containing a metal piece 90 and the metal piece 90 to lower than -0°C, increases the temperatures from a first temperature in the range not higher than 0°C to a second temperature in the range of at least 100°C at a predetermined heating rate under control by a controller 40 to make an analysis target component removed from the metal piece 90. A gas chromatograph 50 removes the analysis target component carried from the reactor core tube 20 by a separation column, and detects the analysis target component by a semiconductor gas sensor.SELECTED DRAWING: Figure 1

Description

The present invention relates to an analyzer and an analysis method for analyzing a metal, and in particular, an analysis for analyzing a gas desorbed from a metal piece by raising the temperature of the metal piece from a low temperature of 0 ° C. or lower to a high temperature of 100 ° C. or higher. Regarding equipment and analysis methods.

For example, as described in Patent Document 1 (Patent No. 5405218), analytical methods called thermal desorption gas analysis method, thermal desorption method, TDS (Thermal Desorption Spectroscopy), etc. have been conventionally known. ing. In the conventional TDS, the sample is heated under a reduced pressure lower than the atmospheric pressure, the gas desorbed from the sample is measured, the relationship between the desorption rate of the gas and the sample temperature (TDS spectrum) is obtained, and the sample is related to the sample. There are analysis methods that try to obtain various information.

Japanese Patent No. 5405218

Conventionally, when analyzing a metal by using a temperature-temperature desorption gas analysis method, a small amount of gas is generated from the metal under reduced pressure (in a vacuum), and the analysis is performed using a mass spectrometer such as Patent Document 1. There is. However, since a mass spectrometer that generates and analyzes a small amount of gas from a metal under reduced pressure (in a vacuum) is a large-scale device, the analyzer described in Patent Document 1 is very large. In particular, when the temperature of the sample is raised after being cooled, the size of the analyzer becomes remarkable. In addition, since it is necessary to detect an extremely small amount of gas generated from the sample, the analyzer becomes expensive. Further, in the analysis method as in Patent Document 1, it is necessary to apply a pretreatment to the metal for analyzing the metal in vacuum, and the pretreatment desorbs a small amount of gas from the metal to reduce the sensitivity. It is difficult to handle, such as the fact that the sensitivity is lowered by foreign matter adhering to the metal at the pretreatment stage.

An object of the present invention is to simplify and facilitate the analysis method of analyzing a sample by using a gas that is desorbed from the sample by raising the temperature after cooling the metal sample and performing the above-mentioned analysis. The purpose is to make the analyzer for this purpose inexpensive and compact.

Hereinafter, a plurality of aspects will be described as means for solving the problem. These aspects can be arbitrarily combined as needed.
The analyzer according to the seemingly relevant aspect of the present invention includes a furnace, a gas chromatograph, and a controller. The reactor includes a core tube containing a sample metal piece, and the core tube and the metal piece are heated from a first temperature of 0 ° C. or lower to a second temperature of 100 ° C. or higher to remove components to be analyzed from the metal piece. Let go. The gas chromatograph has a separation column for separating the components to be analyzed carried from the core tube, and a semiconductor gas sensor for detecting the components to be analyzed separated by the separation column. The controller controls the reactor so as to raise the temperature of the core tube and the metal piece from the first temperature to the second temperature at a predetermined heating rate.
In the analyzer configured in this way, an extremely small amount of the component to be analyzed desorbed below the freezing point from the first temperature of 0 ° C. or lower to 0 ° C. can be separated by a separation column of a gas chromatograph and detected by a semiconductor gas sensor. Therefore, an analyzer that analyzes an extremely small amount of the component to be analyzed desorbed from the metal piece below the freezing point can be inexpensively and compactly configured by a furnace, a gas chromatograph having a separation column and a semiconductor gas sensor, and a controller.

In the analyzer, the reactor includes a first heater that heats the core tube and a cooling tube through which the cooling fluid that cools the core tube flows, and at least a metal piece accommodating area in the core tube is located in the cooling tube. It is also possible to configure the core tube so as to be installed so that the core tube is heated by the radiant heat of the first heater without being substantially heated by the conduction heat of the first heater. ..
In the analyzer configured in this way, the amount of heat escaping from the core tube by heat conduction can be reduced, so that the time required to cool the core tube to the first temperature of 0 ° C. or lower is shortened. Further, in the analyzer, the amount of cooling fluid required to cool the core tube to the first temperature of 0 ° C. or lower is reduced.

The analyzer can also be configured such that the cooling tube has a gap between it and the core tube to allow a portion of the cooling fluid to leak from the cooling tube.
In the analyzer configured in this way, the leaked cold air covers the outer periphery of the cooling pipe to prevent dew condensation on the cooling pipe, and the cooling efficiency of the core pipe can be improved. Further, since the core tube is shielded from the reactor wall by the cooling tube, the influence of its heat conduction can be reduced.

The analyzer is equipped with a second heater that heats the substance to vaporize the liquid substance to generate a cooling fluid, and the controller reduces the power consumption of the second heater as the target temperature increases and exceeds the target temperature. It is also possible to control the rate of temperature rise by controlling the amount of cooling fluid generated by controlling the application of high power when the temperature is lower than the target temperature and the application of low power when the temperature is lower than the target temperature.
In the analyzer configured in this way, the hunting when the temperature is raised at a predetermined heating rate is reduced, and the deviation between the target temperature and the actual core tube temperature is reduced.

In the analyzer, the controller ascends while heating the core tube and metal pieces with the first heater while controlling the PID so that the core tube reaches the target temperature even during the period when the core tube is cooled below the freezing point with the cooling fluid. It can also be configured to control the temperature rate.
In the analyzer configured in this way, the switching from cooling to heating can be smoothly performed, and the hunting when the temperature is raised at a predetermined heating rate is reduced.

The analyzer has a heat insulating container in which a second heater is arranged inside, is connected to a cooling pipe, and stores a cooling fluid, and a caster, which houses a heat insulating container, a furnace, a gas chromatograph, and a controller. It can also be configured to include and.
With the analyzer configured in this way, the space required for the analyzer can be reduced, and the analyzer can be easily moved.

The analyzer can also be configured such that the furnace desorbs the components under analysis from the metal pieces under atmospheric pressure.
With the analyzer configured in this way, it is possible to omit the device required for depressurization and the like, and it is possible to easily realize compactification.

In the analyzer, the metal piece is iron, iron alloy, light metal or light metal alloy, the component to be analyzed is hydrogen gas, the core tube is made of quartz glass, and the first temperature is in the range of -150 ° C or higher and -80 ° C or lower. It can also be configured such that the second temperature is set within the range of 200 ° C. or higher and 600 ° C. or lower.
With the analyzer configured in this way, it is possible to analyze the state in which hydrogen contained in a metal piece of iron, iron alloy, light metal or light metal alloy is desorbed at -80 ° C to 200 ° C, and iron, iron alloy, light metal or It facilitates the analysis of hydrogen brittleness of light metal alloys.

In the analysis method according to the viewpoint of the present invention, a metal piece as a sample is housed in a core tube in a furnace, and the core tube and the metal piece are kept in a furnace from a first temperature of 0 ° C. or lower to a second temperature of 100 ° C. or higher. The temperature is raised at a predetermined heating rate until the metal piece is desorbed from the analysis target component, the analysis target component is carried to the separation column, and the analysis target component separated by the separation column is detected by the semiconductor gas sensor.
With the analysis method configured in this way, an extremely small amount of the analysis target component desorbed from the metal piece below the freezing point can be carried from the core tube to the separation column, and the analysis target component separated by the separation column can be analyzed by the semiconductor gas sensor. It simplifies the analysis of extremely small amounts of components to be analyzed that are desorbed from the metal pieces below the freezing point.

In the analysis method, a cooling fluid is passed through a cooling tube in which at least a metal piece accommodating area is located inside the core tube, the core tube and the metal piece are cooled to a first temperature of 0 ° C. or lower, and the first heater of the reactor is used. It is also possible to heat the core tube by the radiant heat of the first heater without substantially heating with the conducted heat of the above.
In the analysis method configured in this way, the amount of heat escaping from the core tube by heat conduction can be reduced, so that the time required to cool the core tube to the first temperature of 0 ° C. or lower is shortened. Further, in such an analysis method, the amount of cooling fluid required to cool the core tube to the first temperature of 0 ° C. or lower is reduced.

The analysis method can also be configured to cool the core tube with the cooling fluid while leaking the cooling fluid from the gap between the core tube and the cooling tube.
In the analysis method configured in this way, the accuracy of controlling the heating rate can be improved by the cooling fluid leaking from the gap between the core tube and the cooling tube.

In the analysis method, the power consumption of the second heater that heats a liquid substance is reduced as the target temperature increases, and high power is applied when the temperature is above the target temperature of the second heater and low power is applied when the temperature is lower than the target temperature. It is also possible to control the switching to generate a cooling fluid from a liquid substance to raise the temperature of the core tube and the metal piece at a predetermined heating rate.
In the analysis method configured in this way, the hunting when the temperature is raised at a predetermined heating rate is reduced, and the deviation between the target temperature and the actual core tube temperature is reduced.

In the analysis method, even during the period when the core tube is cooled below the freezing point by the cooling fluid, the core tube is heated by the first heater while controlling the PID so that the core tube reaches the target temperature, and the temperature rise rate is controlled. It can also be configured as follows.
In the analysis method configured in this way, the switching from cooling to heating can be smoothly performed, and the hunting when the temperature is raised at a predetermined heating rate is reduced.

The analysis method is as follows: the metal piece is iron, iron alloy, light metal or light metal alloy, the analysis target component is hydrogen gas, the core tube is made of quartz glass, and the first temperature is in the range of -150 ° C or higher and -80 ° C or lower. The second temperature is set in the range of 200 ° C. or higher and 600 ° C. or lower, and the furnace can be configured to desorb hydrogen gas from the metal piece under atmospheric pressure.
With the analysis method configured in this way, it is possible to analyze the state in which hydrogen contained in a metal piece of iron, iron alloy, light metal or light metal alloy is desorbed at -80 ° C to 200 ° C, and iron, iron alloy, light metal or It facilitates the analysis of hydrogen brittleness of light metal alloys.

The analyzer according to another viewpoint of the present invention is
A core tube containing a metal piece as a sample is included, and the core tube and the metal piece are heated from a first temperature of 0 ° C. or lower to a second temperature of 100 ° C. or higher to obtain components to be analyzed from the metal piece. The reactor to be desorbed and
A gas chromatograph having a separation column for separating the analysis target component carried from the core tube and a semiconductor gas sensor for detecting the analysis target component separated by the separation column.
A controller for controlling the reactor so as to raise the temperature of the core tube and the metal piece from the first temperature to the second temperature at a predetermined heating rate is provided.
The core tube is made of a material that does not substantially desorb the gas of the same component as the analysis target component desorbed from the metal piece from the first temperature to the second temperature.

The analysis method according to another viewpoint of the present invention is as follows.
A sample metal piece is housed in the core tube inside the reactor, and
The furnace heats the core tube and the metal piece from a first temperature of 0 ° C. or lower to a second temperature of 100 ° C. or higher at a predetermined heating rate to desorb the components to be analyzed from the metal piece. , The gas of the same component as the component to be analyzed is not substantially desorbed from the core tube.
The component to be analyzed is carried to a separation column and
The component to be analyzed separated by the separation column is detected by a semiconductor gas sensor.
In the analyzer or analysis method configured in this way, the core tube itself does not substantially generate gas of the same component as the component to be analyzed from the first temperature to the second temperature, so that the gas is desorbed from the first temperature below the freezing point. A very small amount of the component to be analyzed can be separated by a separation column of a gas chromatograph and detected by a semiconductor gas sensor. Therefore, an analyzer that analyzes an extremely small amount of the component to be analyzed desorbed from the metal piece below the freezing point is inexpensively and compactly configured. The analysis method for analyzing a very small amount of the component to be analyzed desorbed from the metal piece below the freezing point is simplified.

The analyzer according to another viewpoint of the present invention is
A core tube containing a metal piece as a sample is included, and the core tube and the metal piece are heated from a first temperature of 0 ° C. or lower to a second temperature of 100 ° C. or higher to obtain components to be analyzed from the metal piece. The reactor to be desorbed and
A gas chromatograph having a separation column for separating the analysis target component carried from the core tube and a semiconductor gas sensor for detecting the analysis target component separated by the separation column.
A controller for controlling the reactor so as to raise the temperature of the core tube and the metal piece from the first temperature to the second temperature at a predetermined heating rate is provided.
The gas chromatograph has a calibration tube that uses atmospheric pressure air as a carrier gas and allows a certain amount of sample gas containing the analysis target component to flow through the separation column.

The analysis method according to another viewpoint of the present invention is as follows.
A sample metal piece is housed in the core tube inside the reactor, and
The core tube and the metal piece are heated by the reactor from a first temperature of 0 ° C. or lower to a second temperature of 100 ° C. or higher at a predetermined heating rate to desorb the components to be analyzed from the metal piece.
A certain amount of sample gas containing the component to be analyzed is stored in a calibration tube, and the sample gas is carried to a separation column using air as a carrier.
The component to be analyzed separated by the separation column is detected by a semiconductor gas sensor.
With the analyzer or analysis method configured in this way, a certain amount of sample gas can be stored in the calibration tube and the sample gas can flow through the separation column using air as a carrier, so that the sample gas is extremely desorbed from the first temperature below freezing point. A small amount of the component to be analyzed can be separated by a separation column of a gas chromatograph and detected by a semiconductor gas sensor. Therefore, an analyzer that analyzes an extremely small amount of sample gas desorbed from the metal piece below the freezing point is inexpensively and compactly configured. The analysis method for analyzing a very small amount of the component to be analyzed desorbed from the metal piece below the freezing point is simplified.

The analyzer is an analysis result when the core tube and the metal piece are heated at a predetermined heating rate from the first temperature to the second temperature in a state where the metal piece is not housed in the core tube. (Background) and the analysis result when the core tube and the metal piece were heated at a predetermined heating rate from the first temperature to the second temperature while the metal piece was housed in the core tube. It may be configured to include a computer for comparison.
The analysis method is an analysis result when the core tube and the metal piece are heated at a predetermined temperature rising rate from the first temperature to the second temperature in a state where the metal piece is not housed in the core tube. (Background) and the analysis result when the core tube and the metal piece were heated at a predetermined temperature rising rate from the first temperature to the second temperature while the metal piece was housed in the core tube. May be configured to compare.
The analyzer or analyzer configured in this way can analyze a very small amount of gas component separated from the metal piece without the influence of the background.

The analyzer according to the present invention can perform analysis of a sample using a gas that is desorbed from the sample by raising the temperature after cooling the metal sample with an inexpensive and small device. Further, the analysis method according to the present invention simplifies and makes it easier to handle an analysis method in which a metal sample is cooled, then the temperature is raised, and the sample is analyzed using a gas desorbed from the sample during the temperature rise. it can.

The schematic conceptual diagram for demonstrating the outline of the structure of the analyzer which concerns on embodiment. The flowchart for demonstrating the outline of the analysis method which concerns on embodiment. The graph for demonstrating the cooling capacity of the sample of the analyzer of an embodiment. The graph for demonstrating the analysis result by the analyzer of embodiment. Schematic partially enlarged cross-sectional view showing an example of a furnace of an analyzer. The schematic perspective view which shows an example of the cooling pipe of a furnace. A graph showing an example of the relationship between the reactor temperature and the generated hydrogen concentration for explaining the components to be analyzed generated in the core tube of the reactor. The figure for demonstrating the relationship between the target temperature and the operation of the 1st heater and the 2nd heater. The conceptual diagram which shows an example of the structure of a gas chromatograph. The conceptual diagram which shows an example of the structure of the semiconductor gas sensor used in the gas chromatograph. Schematic front view showing an example of an overview of the analyzer. The schematic diagram which shows an example of the core tube and the cooling tube of the modification A. The schematic diagram which shows an example of the core tube and the cooling tube of the modification B. The schematic diagram which shows an example of the core tube and the cooling tube of the modification C. The schematic diagram which shows an example of the core tube and the cooling tube of the modification D. The schematic diagram which shows an example of the core tube and the cooling tube of the modification E. The schematic diagram which shows an example of the core tube and the cooling tube of the modification F.

(1) Basic Configuration of Analytical Device The analyzer according to the present invention cools a metal sample, then raises the temperature at a predetermined rate of temperature rise, and analyzes the sample using a gas that is desorbed from the sample during the temperature rise. It is an analyzer to perform.
As shown in FIG. 1, the analyzer 1 includes a furnace 10, a controller 40, and a gas chromatograph 50.
The reactor 10 includes a core tube 20 that houses a sample metal piece 90. The furnace 10 cools to a first temperature of 0 ° C. or lower and then raises the temperature to a second temperature of 100 ° C. or higher to desorb the components to be analyzed from the metal piece 90.
Sampling gas is flowing through the core tube 20 of the reactor 10. The components to be analyzed are separated by a separation column 51 carried from the core tube 20 to the separation column 51 (see FIG. 9) of the gas chromatograph 50. The component to be analyzed separated by the separation column 51 is detected by the semiconductor gas sensor 52 (see FIG. 9). As the sampling gas, for example, a dry inert gas is used. Examples of the dried inert gas include dried argon gas.

The controller 40 controls the reactor 10 so as to raise the temperature of the core tube 20 and the metal piece 90 from the first temperature to the second temperature at a predetermined heating rate. The controller 40 preferably raises the temperature of the core tube 20 and the metal piece 90 by a constant temperature per unit time. In other words, it is preferable that the controller 40 linearly raises the temperature of the core tube 20 and the metal piece 90 at a heating rate of, for example, α ° C./min (however, α is constant). When the temperature is raised linearly at a constant temperature rise rate, the passage of time and the temperature change are easily associated with each other, and the relationship between temperature and desorption becomes easy to analyze. The value of α is, for example, 100 ° C./hour. The predetermined rate of temperature rise is not limited to one that changes linearly, and for example, the temperature may rise stepwise. Further, the predetermined heating rate may be set to change according to the period, for example, α ° C./min in a certain period and β ° C./min in another period (however, α and β are It may be constant and α ≠ β).
The core tube 20 is made of a material that does not substantially desorb the gas having the same component as the analysis target component desorbed from the metal piece 90 from the first temperature to the second temperature. The core tube 20 is made of, for example, quartz glass, which will be described later.
Here, "the gas of the same component as the analysis target component is not substantially desorbed from the first temperature to the second temperature" means that even if the gas of the same component as the analysis target component is generated, the semiconductor gas sensor 52 It is smaller than the lower limit that can be measured.

(2) Basic Configuration of Analytical Method As shown in FIG. 2, in the analytical method according to the present invention, first, the core tube 20 is cooled to the first temperature or lower by the reactor 10, and then the metal piece 90 as a sample is used. Is housed in the core tube 20 in the reactor 10 (step ST1).
The temperature is raised from the first temperature to the second temperature at a predetermined heating rate to desorb the component to be analyzed from the metal piece 90 (step ST2).
The component to be analyzed is carried from the core tube 20 to the separation column 51 (step ST3).
The components to be analyzed are separated by the separation column 51. The component to be analyzed separated by the separation column 51 is detected by the semiconductor gas sensor 52 (step ST4).

(3) Detailed configuration of the analyzer 1 (3-1) Overall configuration of the analyzer 1 A gas cylinder 70 for supplying sampling gas is connected to the core tube 20 via a flow path 72. Sampling gas is supplied from the gas cylinder 70 to the core tube 20 at a constant flow rate. A flow rate control valve 71 that controls the flow rate of the sampling gas supplied to the core tube 20 is attached to the flow path 72 of the gas cylinder 70. The flow rate control valve 71 is an electric valve that can increase or decrease the flow rate according to the control signal of the controller 40.
The sampling gas that has passed through the core tube 20 flows into the gas chromatograph 50 through the flow path 73. In the following description, the sampling gas containing the analysis target component after sampling may be referred to as a sample gas.
The flow path 72 for guiding the sampling gas to the core tube 20 and the flow path 73 for guiding the sampling gas from the core tube 20 to the gas chromatograph 50 are treated so that outside air does not leak. The flow path 73 is preferably made of a material in which the component to be analyzed does not easily leak. Such materials include, for example, quartz glass, fluororubber, polyurethane or stainless steel.

The reactor 10 includes a cooling pipe 30, a second heater 12, and a first heater 11 in addition to the core tube 20. A cooling fluid 80 that cools the core tube 20 flows through the cooling pipe 30. The core tube 20 has a storage area 21 for accommodating a sample metal piece 90. The core tube 20 is installed so that the accommodating area 21 of the core tube 20 is located in the cooling tube 30.
The cooling fluid 80 is supplied from the heat insulating container 81. The cooling fluid 80 is, for example, a low temperature gas. The low temperature gas includes, for example, nitrogen gas obtained by vaporizing liquid nitrogen. As the heat insulating container 81, for example, there is a Dewar bottle.
A second heater 12 for supplying the cooling fluid 80 is arranged in the heat insulating container 81. The cooling fluid is stored in the heat insulating container 81 in a liquefied state. The furnace 10 supplies the cooling fluid from the heat insulating container 81 to the cooling pipe 30 by applying heat to the liquefied cooling fluid by the second heater 12 to vaporize the cooling fluid. The greater the amount of heat given by the second heater 12 per unit time, the greater the flow rate of the cooling fluid flowing from the heat insulating container 81 to the cooling pipe 30 per unit time.

In the second heater 12, the state in which power is supplied from the controller 40 is the energized state, and the state in which power is not supplied is the non-energized state. The controller 40 changes the power consumption of the second heater 12 by changing the duty ratio between the energized state and the non-energized state of the second heater 12, and supplies the cooling fluid 80 to the cooling pipe 30 per unit time. change. The longer the energized state of the second heater 12 in the duty ratio, the larger the amount of heat given to the cooling fluid 80 by the second heater 12 per unit time, and the more the flow rate of the cooling fluid flowing through the cooling pipe 30 per unit time increases. Details of the control of the second heater 12 will be described later.
FIG. 3 shows the relationship between the power consumption of the second heater 12 and the temperature of the core tube 20. The curve Cr1 shows the temperature change of the core tube 20 when the second heater 12 continues to consume 120 watts of electric power. The curve Cr2 shows the temperature change of the core tube 20 when the second heater 12 continues to consume 160 watts of electric power. The temperature change of the core tube 20 shown in FIG. 3 is a change when the first heater 11 is in the off state.
At the time of analysis, the second heater 12 is used to cool the core tube 20 to a low temperature of 0 ° C. or lower and the first temperature or lower. For example, the second heater 12 heats the liquid nitrogen to convert a part of the liquid nitrogen into nitrogen gas and supplies it to the cooling pipe 30. At this time, by keeping the first heater 11 in the off state, the temperature of the core tube 20 can be lowered to −100 ° C. as shown in FIG. In this case, the first temperature is −100 ° C. From there, the second heater 12 is controlled to switch between high power application when the temperature is above the target temperature and low power application when the temperature is lower than the target temperature, and PID control is performed on the first heater 11 to achieve a constant temperature rise rate. The temperature of the core tube 20 is raised to 600 ° C. to analyze the components to be analyzed that are desorbed from the sample. As a result of such analysis, the relationship between the temperature of the furnace 10 (the temperature of the sample) and the concentration of generated hydrogen as schematically shown in FIG. 4 can be obtained.
The metal piece 90 of the sample is made of, for example, iron, an iron alloy, copper, a copper alloy, a light metal or a light metal alloy. Examples of light metals include aluminum and titanium. Further, examples of the light metal alloy include an aluminum alloy and a titanium alloy. However, the component of the metal piece 90 to be analyzed is not limited to iron, iron alloy, copper, copper alloy, light metal or light metal alloy, and may be other metal.
The mass of the sample metal piece 90 is, for example, 0.01 grams to several grams.
To investigate the embrittlement of a metal, for example, the hydrogen contained in the metal piece 90 of the sample can be analyzed.

(3-2) Outline of analysis by the analyzer 1 In the analyzer 1, as shown in FIG. 2, first, the core tube 20 is cooled to the first temperature or higher by the reactor 10 and a sampling gas is flowed. After stabilizing the temperature, the sample metal piece 90 is housed in the core tube 20 in the reactor 10.
A sampling gas is introduced into the core tube 20, and the sampling gas is flowed from the core tube 20 to the gas chromatograph 50. Since the density of the sampling gas is low, the sampling gas reaches the same temperature as the core tube 20 immediately after being introduced into the core tube 20.
The temperature is raised from the first temperature to the second temperature at a predetermined heating rate to desorb the component to be analyzed from the metal piece 90. The component to be analyzed desorbed from the metal piece 90 is carried by the sampling gas flowing through the core tube 20 at a constant flow rate.
The components to be analyzed are carried from the core tube 20 to the calibration tube 53 by the sampling gas. A certain amount of sample gas accumulated in the calibration tube 53 is injected into the separation column 51 using atmospheric pressure air as a carrier.
The components to be analyzed are separated by the separation column 51 using atmospheric pressure air as a carrier. The component to be analyzed separated by the separation column 51 is detected by the semiconductor gas sensor 52.

(3-3) Detailed configuration of each part of the analyzer 1 (3-3-1) Configuration of the reactor 10 In FIG. 5, the first heater 11, the core tube 20, and the cooling tube 30 are shown in the configuration of the reactor 10. Is schematically shown. FIG. 6 is a schematic perspective view of the cooling pipe 30. As the first heater 11, for example, an electric furnace can be used. The electric furnace has a metal heating element arranged around a ceramic cylinder 11a. Examples of the metal heating element include a Kanthal wire or a nichrome wire.
The core tube 20 is made of transparent quartz glass. Since the metal piece 90 inside can be visually recognized, the material of the core tube 20 is preferably transparent quartz glass. However, opaque quartz glass can also be used as the material of the core tube 20. The main part of the core tube 20 has, for example, a cylindrical shape having an outer diameter of 15 mm and a length of 300 mm. A part of the main part of the core tube 20 is a storage area 21 for the metal piece 90. The accommodation area 21 is located in the cooling pipe 30. In other words, the cooling pipe 30 is arranged around the accommodating area 21.
The cooling tube 30 is made of transparent quartz glass. However, since the cooling pipe 30 does not come into contact with the sampling gas, it may be formed of, for example, metal or ceramic. A gas inflow pipe 31 and a gas outflow pipe 32 are connected to the cooling pipe 30. For example, low-temperature nitrogen gas flows into the cooling pipe 30 from the gas inflow pipe 31, and the nitrogen gas after cooling the core pipe 20 is discharged from the cooling pipe 30 through the gas outflow pipe 32.
The cooling tube 30 is, for example, a quartz glass tube having an inner diameter of 40 mm and a length of 70 mm. The outer diameter of the cooling pipe 30 is substantially the same as the inner diameter D1 (see FIG. 5) of the ceramic cylindrical body 11a. In other words, the cooling pipe 30 is installed so as to be in contact with the inner surface of the ceramic cylinder 11a of the electric furnace and to be supported by the cylinder 11a.
The cooling pipe 30 is formed with two openings 33 having a diameter D2 (see FIG. 6). The core tube 20 penetrates through these two openings 33. This diameter D2 is larger than the outer diameter of the core tube 20. Therefore, the cooling pipe 30 has a gap 34 between the cooling pipe 30 and the core pipe 20 for leaking a part of the cooling fluid from the cooling pipe 30.

The opening 35 of the cooling pipe 30 at the location where the gas inflow pipe 31 is connected has an area S1. The opening 36 of the cooling pipe 30 at the location where the gas outflow pipe 32 is connected has an area S2. The gap 34 occurs in the two openings 33. Therefore, the area S3 of the gap 34 is (π × (D2 / 2) ^2- π × (D1 / 2) ² ) × 2. The area S3 of the gap 34 is smaller than the area S1 of the opening 35 (= cross-sectional area of the gas inflow pipe 31) (S3 / S1 <1). The value (S3 / S1) obtained by dividing the area S3 of the gap 34 by the area of the opening 35 is set so as to satisfy the equation of, for example, 0.6 <S3 / S1 <0.9. Here, the area S1 of the opening 35 and the area S2 of the opening 36 are set to be the same. Since the area S3 of the gap 34 is smaller than the area S1 (= cross-sectional area of the gas inflow pipe 31) of the opening 35 (S3 / S1 <1), a part of the cooling fluid is made of ceramic through the gas outflow pipe 32. It is discharged to the outside of the cylindrical body 11a. For example, in the case of nitrogen gas, it may be configured to be released into the atmosphere as it is.

FIG. 7 shows the concentration of generated hydrogen and the temperature of the furnace 10 (core tube) detected by a gas chromatograph by flowing argon gas as a sampling gas in a quartz glass core tube 20 without a sample metal piece 90. The relationship with the temperature of 20) is shown. As shown in FIG. 7, the quartz glass core tube 20 does not substantially generate hydrogen gas to be detected at 600 ° C. or lower. Therefore, when the analyzer 1 provided with such a quartz glass core tube 20 is used, for example, -100 ° C. is set as the first temperature and 600 ° C. is set as the second temperature, and the temperature is between the first temperature and the second temperature. The concentration of hydrogen generated from iron or iron alloy can be detected accurately.
The core tube 20 penetrates the cooling pipe 30 and is supported by the cooling pipe 30. In other words, the core tube 20 is not in contact with the ceramic cylinder 11a of the electric reactor. Therefore, the core tube 20 is heated by the radiant heat of the first heater 11, and is not substantially heated by the conduction heat from the first heater 11. When the core tube 20 is cooled, the core tube 20 is not supplied with heat from the electric reactor by heat conduction. As a result, the cooling time of the core tube 20 of the analyzer 1 is shorter than that in the case where the core tube 20 is in contact with the cylindrical body 11a.
The second heater 12 is a heater that can be used by immersing it in a liquid cooling fluid, for example, liquid nitrogen. For example, a throw-in heater is used as the second heater 12.

(3-3-2) Configuration of Controller 40 The controller 40 includes, for example, a central arithmetic processing circuit (not shown), a memory (not shown), a first power supply device (not shown), and a second controller 40. It is equipped with a power supply device (not shown). The controller 40 is connected to a temperature sensor 41 that detects the temperature of the accommodation region 21 of the core tube 20. For the temperature sensor 41, for example, a heat transfer pair can be used. For example, a CPU can be used for the central arithmetic processing circuit. The first power supply device is a device that supplies power to the first heater 11. The second power supply device is a device that supplies power to the second heater 12. The first power supply device and the second power supply device of the controller 40 supply power to the first heater 11 and the second heater 12 in response to a command from the central arithmetic processing circuit. The first power supply device is PID-controlled by the central arithmetic processing circuit based on the temperature of the core tube 20 detected by the temperature sensor 41, using the heat generation amount (electric power) of the first heater 11 as the operation amount. Here, the case where PID control is used will be described, but the control method is not limited to PID control. Controls other than PID control, for example, proportional control (P control) or proportional integral control (PI control) may be used. The second power supply device is controlled by the central arithmetic processing circuit based on the temperature of the core tube 20 detected by the temperature sensor 41.
An example of temperature control of the core tube 20 by the controller 40 is shown in FIG. Assuming that −100 ° C. is the first temperature, the controller 40 uses the second heater 12 to reduce the temperature of the core tube 20 with the first heater 11 turned off, as described with reference to FIG. Cool to 100 ° C.

In the memory of the controller 40, the target temperature of the core tube 20 which is heated at a constant temperature rising rate is stored. Since the controller 40 raises the temperature from -100 ° C. at a constant rate of temperature rise, the PID control of the first heater 11 is started from -100 ° C. Further, since the controller 40 raises the temperature from -100 ° C. at a constant temperature rise rate while maintaining a low temperature, the second heater 12 also applies high power when the temperature is equal to or higher than the target temperature and low power when the temperature is lower than the target temperature. Starts control to switch.
The second heater 12 increases the power consumption of the second heater 12 when the measured temperature of the temperature sensor 41 is equal to or higher than the target temperature as compared with the case where the measured temperature of the temperature sensor 41 is smaller than the target temperature. However, the second heater 12 is PWM-controlled, and the energized state and the non-energized state are periodically repeated. The controller 40 changes the power consumption of the second heater 12 by changing the duty ratio between the energized state and the non-energized state. It is assumed that the duty ratio Du is given by Du = P2 / P1 using the repetition period P1 and the period P2 of the energized state for each cycle. For example, when the duty ratio Du100 near −100 ° C. and the duty ratio Du5 near −5 ° C. are compared, Du100> Du5 even when the measurement temperature is smaller than the target temperature and the measurement temperature is equal to or higher than the target temperature.
As the target temperature increases, the electric power supplied to the first heater 11 increases, and conversely, the electric power supplied to the second heater 12 decreases. For example, as shown in FIG. 8, the second heater 12 may be turned on to supply the cooling fluid even at 0 ° C. or higher. However, in order to reduce unnecessary power consumption, the second heater 12 is always turned off when the power supplied to the first heater 11 is the predetermined power PW1 or more (when the time is t1 or more).

(3-3-3) Configuration of Gas Chromatograph 50 As shown in FIG. 9, the gas chromatograph 50 includes a separation column 51, a semiconductor gas sensor 52, a calibration tube 53, pumps 54a and 54b, a filter 55, and a flow rate regulator. It includes 56, a flow sensor 57, a needle valve 58, and four solenoid valves 59.
The separation column 51 is a tubular device that separates a sample introduced by a sampling gas into a plurality of components at a predetermined column temperature. Here, the case where the separation column 51 is a filling column will be described, but a capillary column may be used for the separation column 51.
The separation column 51 separates the sample, for example, at a predetermined column temperature. A column heater (not shown) is attached to the separation column 51 in order to bring the separation column 51 to a predetermined column temperature. In the separation column 51, air containing no component to be analyzed is used as the carrier gas. The carrier gas is flowed through the separation column 51 at a constant flow velocity.
The outer shell of the separation column 51 is, for example, a fluororesin cylindrical tube that does not allow the components to be analyzed to permeate. The inside of the cylindrical tube is filled with a filler that forms a stationary phase. The filler is, for example, diatomaceous earth, molecular sieve, porous polymer, or alumina. Further, the filler may be coated with a liquid phase in order to form a stationary phase.
For example, air can be used as the carrier gas of the gas chromatograph 50. The pump 54a is a device that allows air as a carrier gas to flow through the gas chromatograph 50. The flow rate regulator 56 adjusts the amount of carrier gas. The filter 55 is a device for purifying the carrier gas. The filter 55 is configured to remove, for example, fine dust. The filter 55 may include, for example, a gas adsorbent and / or a gas decomposition catalyst to purify the carrier gas.
The flow rate regulator 56 adjusts the flow rate of the carrier gas sent to the separation column 51 so as to be a constant amount. As the flow rate regulator 56, for example, a linear valve having a characteristic that the flow rate is proportional to the valve opening within a predetermined range is used. The flow rate sensor 57 measures the flow rate of the carrier gas sent to the separation column 51.
The calibration tube 53 is a tube for calibrating a predetermined amount of sample gas. The calibration tube 53 is made of, for example, quartz glass or a fluororesin made of the same material as the separation column 51.
The needle valve 58 has a needle-shaped valve body and is a valve that regulates the flow rate of the sample gas. In this gas chromatograph 50, once the flow rate is adjusted, the flow rate is not adjusted by the needle valve 58. However, the opening degree of the needle valve 58 may be adjusted by the computer 60. The pump 54b is a device for flowing the sample gas through the calibration tube 53. For the pump 54b, for example, a piezo pump can be used.
In FIG. 9, the flow path through which the carrier gas flows in the sample gas sampling state is shown by a chain line, and the flow path through which the sample gas flows is shown by a broken line. In FIG. 9, the flow path through which the carrier gas flows in the measurement state is shown by a two-point difference line. The sample gas sampling state and the measurement state are switched by four solenoid valves 59.
In the sample gas sampling state, the carrier gas that has passed through the filter 55 flows from the flow rate regulator 56 to the separation column 51 via the flow rate sensor 57. Further, in the sample gas sampling state, the sample gas flows from the furnace 10 to the calibration pipe 53, the needle valve 58, and the pump 54b.
In the measurement state, the carrier gas that has passed through the filter 55 flows from the flow rate regulator 56 to the separation column 51 via the flow rate sensor 57 and the calibration tube 53. As a result, a certain amount of sample gas calibrated in the calibration tube 53 can be flowed through the separation column 51.
For example, the measurement time required for one sample gas of the calibration tube 53 is, for example, 4 to 8 minutes. In one measurement state, a fixed amount (for example, 2 cc to 5 cc) of sample gas calibrated by the calibration tube 53 can be poured into the separation column 51 and measured by the semiconductor gas sensor 52. The waiting time from one measurement state to the next measurement state is, for example, about 1 minute.

FIG. 10 is a conceptual diagram showing a semiconductor gas sensor 52 used in the gas chromatograph 50 of FIG. The semiconductor gas sensor 52 shown in FIG. 10 includes a gas sensitive body 52a containing a metal oxide semiconductor as a main component. As the metal oxide semiconductor, for example, tin oxide, tungsten oxide, titanium oxide or zinc oxide is used.
In addition to the gas sensitive body 52a, the semiconductor gas sensor 52 has a coil-shaped heater combined electrode 52b embedded in the gas sensitive body 52a and the gas sensitive body 52a so as to penetrate the center or the vicinity of the coil of the heater combined electrode 52b. The semiconductor resistance detection electrode 52c and the electrode pads 52d and 52e embedded in the above are provided.
Both ends of the heater combined electrode 52b are connected to two electrode pads 52d. The semiconductor resistance detection electrode 52c is connected to the electrode pad 52e. The electrode pads 52d and 52e are used to extract a change in load resistance between the heater combined electrode 52b and the semiconductor resistance detecting electrode 52c. The semiconductor gas sensor 52 detects the gas component to be detected based on the change in the resistance value of the gas sensitive body 52a. The change in the resistance value of the gas sensitive body 52a is input to the computer 60.

(3-3-4) Configuration of Computer 60 The analyzer 1 further includes a computer 60. Information on the temperature rise is transmitted from the controller 40 to the computer 60, and information on the detection result of the semiconductor gas sensor 52 is transmitted from the gas chromatograph 50. The information regarding the detection result of the semiconductor gas sensor 52 includes a change in the resistance value of the gas sensor 52a. The computer 60 can associate the temperature of the metal piece 90 with the desorbed component to be analyzed (for example, hydrogen gas) from the information on the temperature rise and the information on the detection result of the semiconductor gas sensor 52.
The user can use the keyboard of the computer 60 (not shown) to enter the parameters required for the analysis. The parameters required for the analysis include, for example, the value of the first temperature, the value of the second temperature, and the rate of temperature rise.
The computer 60 analyzes the blank state when the core tube 20 and the metal piece 90 are heated at a predetermined temperature rising rate from the first temperature to the second temperature in a state where the metal piece 90 is not housed in the core tube 20. I remember (background). The computer 60 obtains the analysis result of the sample when the core tube 20 and the metal piece 90 are heated at a predetermined temperature rising rate from the first temperature to the second temperature while the metal piece 90 is housed in the core tube 20. I remember. Then, the computer 60 subtracts the value of the analysis result in the blank state from the analysis result of the sample. By performing such a calculation, the computer 60 reduces the measurement error that occurs in the analysis result of the sample. As a result, the analyzer 1 can analyze an extremely small amount of gas component separated from the metal piece 90.

(3-3-5) Appearance of Analytical Device 1 Analytical device 1 is housed in a gantry 100. The size of the gantry 100 is, for example, a height H1 of 70 cm, a width W1 of 90 cm, and a depth (not shown) of 50 cm. In a 70 cm × 90 cm × 50 cm rectangular parallelepiped space of the gantry 100, a furnace 10, a controller 40, a gas chromatograph 50, a heat insulating container 81, and a weight scale 82 for measuring the weight of the heat insulating container 81 are placed. It is stored. The computer 60 is placed on the top plate 101 of the gantry 100. The total height of the analyzer 1 including the computer 60 is, for example, 100 cm.
As described above, the occupied area of the analyzer 1 when the entire analyzer 1 is viewed from above is 90 cm × 50 cm. As described above, if the occupied area of ^{the analyzer 1 can be reduced to 0.5 m 2} or less, the analyzer 1 can be arranged side by side with an office desk or the like, which saves space and is convenient.
Casters 110 are attached to the bottom 102 of the gantry 100 at the four corners of the bottom 102. The gantry 100 can be easily moved by the casters 110.

(4) Modification example (4-1) Modification example A
In the above embodiment, the gas inflow pipe 31 and the gas outflow pipe 32 are arranged on the same side surface of the cooling pipe 30. By arranging the gas inflow pipe 31 and the gas outflow pipe 32 on the same side surface of the cooling pipe 30 in this way, the outflow and inflow of the cooling fluid (for example, nitrogen gas) can be limited to one direction, so that the furnace 10 can be easily made compact. Become. However, as shown in FIG. 12A, the gas inflow pipe 31 and the gas outflow pipe 32 may be arranged on different sides of the cooling pipe 30. When the gas inflow pipe 31 and the gas outflow pipe 32 are arranged at opposite pole positions across the cooling pipe 30, the bias of the flow of the cooling fluid in the cooling pipe 30 can be reduced.
(4-2) Modification B
In the above embodiment, the outer diameter of the core tube 20 is configured to be the same inside the cooling tube 30. However, as shown in FIG. 12B, the core tube 20 is provided with a portion 38 having a large outer diameter and a portion 39 having a small outer diameter, and the boundary between the thick portion 38 and the portion 39 having a small outer diameter is the inside of the cooling pipe 30. The reactor 10 may be configured to be arranged in.
As shown in FIG. 12B, if a thin portion 39 is provided in the outer diameter of the core tube 20, the dead space of the core tube 20 can be reduced. Further, since the boundary between the thick portion 38 and the portion 39 having a small outer diameter acts as a stopper for the metal piece 90, it becomes easy to set the metal piece 90.
(4-3) Modification C
The temperature sensor 41 may be brought into contact with the tube wall of the core tube 20 in the cooling tube 30 as shown in FIG. 12C. In the cooling pipe 30, the temperature of the pipe wall of the core tube 20 and the temperature of the metal piece 90 are substantially equal, so that the temperature of the pipe wall is measured by a temperature sensor 41, for example, a heat transfer pair as shown in FIG. 12C. Therefore, the temperature of the metal piece 90 can be measured.

(4-4) Modification D
The temperature sensor 41 may measure the temperature of the metal piece 90 outside the core tube 20 inside the cooling tube 30 as shown in FIG. 12D. In this case, in order to facilitate the estimation of the temperature of the core tube 20, it is preferable to use a member made of quartz glass similar to the core tube 20 and having the same thickness at the portion where the temperature sensor 41 contacts.
(4-5) Modification E
As shown in FIG. 12D, the temperature sensor 41 may be provided with a bag-shaped portion 22 protruding toward the inside of the core tube 20 in the cooling pipe 30, and may be arranged in the bag-shaped portion 22. .. In the cooling pipe 30, the temperature of the pipe wall of the core tube 20 and the temperature of the metal piece 90 are substantially equal, so that the temperature of the pipe wall is measured by a temperature sensor 41, for example, a heat transfer pair as shown in FIG. 12C. Therefore, the temperature of the metal piece 90 can be measured. The bag-shaped portion 22 can also be held as a stopper for the metal piece 90.
(4-6) Modification F
A protrusion 23 may be provided in the core tube 20 with quartz glass, and the protrusion 23 may be used as a stopper for the metal piece 90.
(4-7) Modification G
In the above embodiment, when controlling the second heater 12, for example, when comparing the duty ratio Du100 near −100 ° C. and the duty ratio Du5 near −5 ° C., the measurement temperature is measured even when the measurement temperature is smaller than the target temperature. The case of controlling so that Du100> Du5 even when the temperature is equal to or higher than the target temperature has been described.
However, it may be controlled so that, for example, Du100> Du5 only when the measured temperature is smaller than the target temperature. Alternatively, it may be controlled so that, for example, Du100> Du5 only when the measurement temperature is equal to or higher than the target temperature.
(4-8) Modification H
In the above embodiment, the case where the sampling gas (argon gas) and the carrier gas (air) are different from each other has been described. However, the same type of gas may be used for the sampling gas and the carrier gas.

(5) Features (5-1)
In the analyzer 1 and the analysis method of the embodiment described above, as described with reference to FIG. 3, a first temperature of 0 ° C. or lower (for example, -100 ° C.) to a second temperature of 100 ° C. or higher (for example, 600 ° C.) Up to ° C.), the core tube 20 is made of a material that does not substantially generate gas having the same component as the component to be analyzed. In this analyzer 1 and this analysis method, an extremely small amount of a component to be analyzed desorbed from a first temperature of 0 ° C. or lower to 0 ° C. below a freezing point is separated by a separation column 51 of a gas chromatograph 50 and detected by a semiconductor gas sensor 52. it can. As described above, the analyzer 1 is inexpensively and compactly configured by the furnace 10, the controller 40, and the gas chromatograph 50 having the separation column 51 and the semiconductor gas sensor 52. Further, as described above, the analysis method carries an extremely small amount of the analysis target component desorbed from the metal piece below the freezing point from the core tube 20 to the separation column 51, and the analysis target component separated by the separation column 51 is the semiconductor gas sensor 52. It is simpler than before, such as analyzing with.
(5-2)
In the analyzer 1 and the analysis method according to the embodiment, the core tube 20 shown in FIG. 5 is not substantially heated by the conduction heat of the first heater 11, but is heated by the radiant heat of the first heater 11. It is installed like this. Therefore, the amount of heat that escapes from the core tube 20 by heat conduction is small, and the time required to cool the core tube 20 to the first temperature (for example, −100 ° C.) of 0 ° C. or lower is shortened. For example, in the example shown in FIG. 3, the core tube 20 is cooled to −100 ° C. in a few minutes. Further, in such an analyzer 1 and an analysis method, the amount of cooling fluid (for example, nitrogen gas obtained by vaporizing liquid nitrogen) required to cool the core tube 20 to a first temperature of 0 ° C. or lower is reduced. Will be done.

(5-3)
In the analyzer 1 and the analysis method according to the embodiment, the cooling pipe 30 has a gap 34 between the cooling pipe 30 and the core pipe 20 for leaking a part of the cooling fluid from the cooling pipe 30. Then, the core tube 20 is cooled by the cooling fluid while leaking the cooling fluid (for example, nitrogen gas) from the gap 34 between the core tube 20 and the cooling tube 30. As a result, the leaked cold air covers the outer periphery of the cooling pipe 30 to prevent dew condensation on the cooling pipe 30, and the cooling efficiency of the core pipe 20 can be improved. Further, since the core tube 20 is shielded from the cylindrical body 12a which is the reactor wall by the cooling tube 30, the influence of the heat conduction can be reduced.
(5-4)
In the analyzer 1 and the analysis method according to the embodiment, the second heater 12 heats the substance in order to vaporize the liquid substance (for example, liquid nitrogen) and generate a cooling fluid (nitrogen gas). As the electric power supplied to the second heater 12 increases, the amount of the second heater 12 vaporizing the liquid substance increases, and a large amount of cooling fluid can be supplied. The controller 40 controls the power consumption of the second heater 12 to switch between high power application when the temperature is above the target temperature and low power application when the temperature is lower than the target temperature while reducing the power consumption as the target temperature increases. The rate of temperature rise is controlled by controlling the amount of power generated. For example, in the vicinity of -100 ° C, the power consumption of the second heater 12 when the temperature is equal to or higher than the target temperature is set to 100 watts, and in the vicinity of -5 ° C, the power consumption is set to 20 watts. (When power is applied), the higher the target temperature, the smaller the power supplied to the second heater 12. Further, for example, when the power consumption is lower than the target temperature of the second heater 12 in the vicinity of -100 ° C, the power consumption is 50 watts, and in the vicinity of -5 ° C, the power consumption is 10 watts. Also at the time of application), the controller 40 reduces the power supplied to the second heater 12 as the target temperature becomes higher. By such control, the hunting when the temperature is raised at a predetermined heating rate is reduced, and the deviation between the target temperature and the actual temperature of the core tube 20 is reduced.
(5-5)
In the analyzer 1 and the analysis method according to the embodiment, the controller 40 controls the core tube 20 so that the core tube 20 reaches the target temperature even during the period in which the core tube 20 is cooled below the freezing point by the cooling fluid. The temperature rise rate is controlled while heating the metal piece 90 with the first heater 11. For example, as compared with the case where the temperature is raised only by reducing the amount of the cooling fluid, the core tube 20 is heated while being cooled as in the analyzer 1 and the analysis method, so that the switching from cooling to heating can be smoothly performed. It is possible to reduce the hunting when the temperature is raised at a predetermined heating rate.

(5-6)
In the analyzer 1 and the analysis method according to the embodiment, the furnace 10 desorbs the analysis target component (for example, hydrogen gas) from the metal piece 90 under atmospheric pressure. Therefore, as compared with the conventional method of desorbing the analysis target component under reduced pressure (for example, in vacuum), the device required for depressurizing or the like can be omitted, and the analyzer 1 can be made compact and the analysis method can be simplified. It can be easily realized.
(5-7)
In the analyzer 1 and the analysis method according to the embodiment, the core tube 20 is made of quartz glass, the metal piece is iron or an iron alloy, and the first temperature is set within the range of −150 ° C. or higher and −80 ° C. or lower. When the second temperature is set within the range of 200 ° C. or higher and 600 ° C. or lower and hydrogen gas is desorbed as a component to be analyzed, hydrogen embrittlement analysis of iron or an iron alloy can be easily performed.
(5-8)
In the analyzer 1 according to the embodiment, a furnace 10, a controller 40, a gas chromatograph 50, a computer 60, and a heat insulating container 81 are housed in a pedestal 100 provided with casters 110. The analyzer 1 can move the main instruments constituting the analyzer 1 by the gantry 100. As shown in FIG. 11, the analyzer 1 thus assembled by the gantry 100 with casters 110 occupies a small space and is easy to move.
Although one embodiment of the present invention has been described above, the present invention is not limited to the above embodiment, and various modifications can be made without departing from the gist of the invention. In particular, the plurality of embodiments and modifications described herein can be arbitrarily combined as needed.

1 Analyzer 10 Furnace 11 1st heater 12 2nd heater 20 Core tube 30 Cooling tube 34 Gap 40 Controller 41 Temperature sensor 50 Gas chromatograph 51 Separation column 52 Semiconductor gas sensor 80 Cooling fluid 90 Metal piece

Claims (9)

A core tube containing a metal piece as a sample is included, and the core tube and the metal piece are heated from a first temperature of 0 ° C. or lower to a second temperature of 100 ° C. or higher to obtain components to be analyzed from the metal piece. The reactor to be desorbed and
A gas chromatograph having a separation column for separating the analysis target component carried from the core tube and a semiconductor gas sensor for detecting the analysis target component separated by the separation column.
An analyzer comprising a controller for controlling the reactor so as to raise the temperature of the core tube and the metal piece from the first temperature to the second temperature at a predetermined heating rate. The reactor includes a first heater that heats the core tube and a cooling tube through which a cooling fluid that cools the core tube flows.
The core tube is installed so that at least the accommodating area of the metal piece in the core tube is located in the cooling tube.
The core tube is installed so as to be heated by the radiant heat of the first heater without being substantially heated by the conduction heat of the first heater.
The analyzer according to claim 1. The cooling pipe has a gap between the cooling pipe and the core pipe for leaking a part of the cooling fluid from the cooling pipe.
The analyzer according to claim 2. A second heater for heating the substance to vaporize the liquid substance to generate the cooling fluid is provided.
The controller controls to switch between high power application when the target temperature is higher than the target temperature and low power application when the target temperature is lower than the target temperature while reducing the power consumption of the second heater as the target temperature becomes higher. The temperature rise rate is controlled by controlling the amount of power generated.
The analyzer according to claim 2 or 3. The controller heats the core tube and the metal piece with the first heater while controlling the PID so that the core tube reaches the target temperature even during the period in which the core tube is cooled below the freezing point by the cooling fluid. While controlling the temperature rise rate,
The analyzer according to claim 4. A heat insulating container in which the second heater is arranged, connected to the cooling pipe, and stores the cooling fluid, and a heat insulating container.
It has casters and includes the heat insulating container, the furnace, the gas chromatograph, and a stand for accommodating the controller.
The analyzer according to claim 4 or 5. The furnace desorbs the analysis target component from the metal piece under atmospheric pressure.
The analyzer according to any one of claims 1 to 6. The metal piece is iron, an iron alloy, a light metal or a light metal alloy,
The component to be analyzed is hydrogen gas,
The core tube is made of quartz glass
The first temperature is set within the range of −150 ° C. or higher and −80 ° C. or lower, and the second temperature is set within the range of 200 ° C. or higher and 600 ° C. or lower.
The analyzer according to any one of claims 1 to 7. A sample metal piece is housed in the core tube inside the reactor, and
The core tube and the metal piece are heated by the reactor from a first temperature of 0 ° C. or lower to a second temperature of 100 ° C. or higher at a predetermined heating rate to desorb the components to be analyzed from the metal piece.
The component to be analyzed is carried to a separation column and
An analysis method in which a semiconductor gas sensor detects the analysis target component separated by the separation column.

Images