JPH02141655A - Apparatus for analyzing atmospheric gas component - Google Patents

Abstract

PURPOSE:To make it possible to analyze gas component continuously by providing a mass spectrometer which is connected to a gas introducing part through a valve, providing an exhaust system which is connected to the mass spectrometer, and providing a data processing part which processes the output from the mass spectrometer. CONSTITUTION:When an exhaust pump in a gas introducing part 1 is operated, gas is sucked into the inside through an introducing port and a heated pipe. Part of the sucked gas is introduced into a gas analyzing part 2. The quantity of the gas is regulated by using a valve in an exhaust system in the introducing part 1 or a valve between the introducing part 1 and the analyzing part 2 so that the quantity is suppressed to a degree less than a vacuum state within a range that is allowed by a vacuum gate in a gas analyzer (mass spectrometer) 4. Thus the constant quantity of gas is continuously introduced into the analyzing part 2 through the gas introducing port. The component of the introduced gas is continuously analyzed. Therefore, the time change in component can be traced.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention is applicable to the analysis of odor components, the analysis of atmospheric components in buildings and underground passages, and the analysis of atmospheric gas components in manufacturing experiment equipment such as inside tanks and furnaces. , relates to a gas component analyzer used for analyzing fire-generating gas and toxic gas components.

(Prior art) Gas components can be analyzed directly using a gas chromatograph, a mass spectrometer, or a gas chromatograph-mass spectrometer that combines both, or can be quantitatively determined by dissolving them in a solution and titrating the dissolved components. It was used.

However, both have the following problems.

(a) In the case of the former dry method, continuous gas analysis is difficult because all analyzes involve injecting gas into the apparatus using a micro cylinder. Furthermore, in the case of high-temperature generated gas, it must be cooled and may condense within the cylinder and not be detected.

(0) The latter wet method and gas chromatography analysis are analyzes of specific components, and in the case of a gas in which it is not clear what kind of gas components are contained, component analysis cannot be performed.

It had the following drawbacks.

(Problem N to be Solved by the Invention) An object of the present invention is to provide an apparatus that can analyze the components of a gas to be analyzed on the spot and in that state.

(Means for Solving Problem 1) In order to achieve the above object, the present invention includes a heated gas introduction section, a mass spectrometer connected to the gas introduction section via a valve, and a mass spectrometer connected to the gas introduction section through a valve. The present invention is characterized by an atmospheric gas component analyzer comprising an exhaust system connected to the mass spectrometer, and a data processing section that processes the output from the mass spectrometer.

(Function) In the present invention, since a mass spectrometer is used to analyze gas components, sampling is unnecessary and analysis can be performed continuously.

(Example) Next, examples of the present invention will be described.

It should be noted that the embodiments are merely illustrative, and it goes without saying that various changes and improvements may be made without departing from the spirit of the present invention.

FIG. 1 shows the apparatus of the present invention, in which 1 indicates a gas introduction section, 2 indicates a gas component analysis section, and the gas component analyzer includes a valve 3, a mass spectrometer 4, an exhaust system 5, and a data processing section 6. It is configured.

The gas analysis section 2 used a 1Jlt quantity analyzer as a gas detector. The interior of the mass spectrometer is equipped with an exhaust pump because it is necessary to maintain a high vacuum. Although a mass spectrometer was used as a gas component analyzer, a Fourier transform infrared absorption analyzer (Fl
-IR) may be used; in this case, an exhaust system is not required. However, in the case of a Fourier transform infrared absorption spectrometer, there is too much information included in the spectrum due to intramolecular vibration information, and although it is very effective for specific gas components such as CO, it can be difficult to understand. . In this respect, mass spectrometry can analyze various components with high sensitivity and is considered to be more versatile.

When using a mass spectrometer, a cooling gas trap for gas concentration or a gas chromatography column for gas separation may be installed between the gas inlet and the gas inlet to expand analysis information. However, in these cases, This is not a continuous gas component analysis, but an analysis of gas sampled over a certain period of time.

Examples of the configuration of the gas introduction part are shown in Figures 2 to 4.
In the figure, 7 is a gas introduction pipe with a small diameter, and 8 is a cylindrical main body with an inner diameter larger than 7, which is provided with a heating heater. 9 is a partition wall having small holes, IO is a valve, 11
indicates a leak valve, 12 indicates a rotary pump, the second
The difference between FIGS. 2 to 4 is that the gas components introduced from FIGS. 2 to 4 are easier to reach the analysis section as they are.

One of the basic ideas is to warm the gas introduction path to prevent condensation of gas components due to cold points.The other is to suck in the gas with an exhaust pump, and some of the gas is continuously fed into a gas component analyzer. Most of the sucked gas goes to the exhaust pump and is released into the atmosphere, but some of it enters the gas component analyzer through a thin orifice-like tube, small hole, or valve.

The reason why the gas introduction section and the gas component analysis section are separated through such a small space is related to the mass spectrometer used for the gas component analysis. That is, the inside of the mass spectrometer is 10-
h~l Q-''TorrO high vacuum is required, but the degree of vacuum in one gas introduction section is at most about 1O-2Torr.Therefore, it is necessary to separate the re-vacuum through such a small hole (in the partition wall 9). This allows gas components to pass through.

The apparatus of the present invention is movable, and is moved to a location where gas analysis is desired, and the tip of the gas introduction section is attached to the part to be measured.

When the exhaust pump in the gas inlet is operated, gas is sucked into the interior through the heated pipe from the inlet. A part of the aspirated gas is introduced into the gas component analysis section, but this amount is controlled by the vacuum gauge in the gas analyzer (mass spectrometry needle) so that the vacuum drop is within an allowable range. It is adjusted using the valve in the exhaust system of the section or the valve 10 between the gas introduction section and the analysis section. Thereby, a certain amount of gas is continuously introduced into the gas analysis section from the gas inlet. The components of this introduced gas are continuously analyzed. Therefore, changes in components over time can be tracked with the device of the present invention.

(Example 1) A gas inlet of the type shown in FIG. 4 was used, and a system 11 using a quadrupole mass spectrometer was used as a gas analyzer. The heating temperature of the introduction section is 300°C.

Using this device, we analyzed the gas generated when wood was heated. The measurement results at this time are shown in FIG.

In Figure 5, time (minutes) is plotted on the horizontal axis, and intensity is plotted on the vertical axis. Combustion gases such as and wood decomposition gas components such as furfural were detected, and at the same time, changes in the amount of each component generated could be detected.

The gas introduction part of Example (1) was changed to the type shown in Fig. 3, but
Similar results were obtained.

Also, examples! Although the gas introduction part in 1) was changed to the type shown in Fig. 2, the same result was obtained.

The above example shows continuous analysis of the components directly introduced as gas, but next we will look at the mixed gas components by trapping the directly introduced components, condensing and condensing them, and then separating the concentrated gas in detail. An example of analysis is shown below.

(Example 2) A system was created in which a cold trap for concentrating the introduced gas and a gas chromatography column for separating gas components were attached to a system using a gas inlet of the type shown in Figure 2 and a quadruple scratching mass spectrometer. , conducted an analysis of cigarette smoke.

First, cigarette smoke is sucked in and then passed through a tube-type trap cooled with dry ice and expelled. After a certain period of time, stop the gas introduction and heat the trap (approximately 350°
C), the cooled and coagulated gas components are vaporized again and introduced into the gas chromade column. The gas components separated by the column came out at different times for each successive component, which was then subjected to mass spectrometry. The results are shown in FIG.

In addition to a large amount of nicotine, cigarette smoke also detected alkylfuran components such as furfural and components such as toluene and xylene (effects of the invention). a gas introduction section;
By comprising a mass spectrometer connected to the gas introduction section via a valve, an exhaust system connected to the mass spectrometer, and a data processing section that processes the output from the mass spectrometer needle. (a) Since the gas is directly introduced into the analyzer, there is no need for sampling using a cylinder or the like. Furthermore, since such sampling is not performed during the operation, errors such as gas condensation within the cylinder are eliminated.

(b) Continuous gas component analysis is possible. Therefore, changes in components and generation amount over time can be investigated.

(c) Since the device is movable, gas analysis can be performed on site as is.

(d) Since it is a forced gas introduction system, it can be installed directly into equipment that generates gas, such as inside a furnace, tank, or thermal analyzer.
Gas analysis can be performed.

It has the following effects.

[Brief explanation of the drawing]

FIG. 1 shows the atmospheric gas component analyzer of the present invention, FIGS. 2 to 4 show the gas introduction section, and FIGS. 5 and 6 show the analysis results. l...Gas introduction section, 2...Gas component analysis section, 3...
・Valve, 4...Mass spectrometer, 5...Exhaust system, 6.
...Data processing section, 7...Gas introduction pipe, 8...Main body, 9...Partition wall, 1O...Valve, 11...Leak valve, 12...Rotary pop. Figure Figure Figure Figure

Claims (1)

[Claims] a heated gas introduction section, a mass spectrometer connected to the gas introduction section via a valve, an exhaust system connected to the mass spectrometer, and data processing the output from the mass spectrometer. An atmospheric gas component analyzer characterized by comprising a processing section.