JP5250240B2 - Formation gas concentration measuring apparatus and formation gas concentration measuring method - Google Patents

Description

  The present invention relates to a formation gas concentration measuring device and a formation gas concentration measurement method for measuring the concentration of a gas component contained in the formation when excavating the formation by shield excavation, drilling, or the like.

When a large amount of flammable gas such as methane gas is accumulated in the formation when performing shield excavation work or hot spring boring work for muddy water and mud pressure, the combustible gas that has accumulated in the formation during shield excavation or boring There is a possibility that the flammable gas may be filled in the work area such as the inside of the mine. Therefore, in the shield method of mud and mud pressure, when conducting shield digging, sample the mud and mud sample mixed with excavated earth and sand, measure the gas concentration in the formation, and it is necessary according to the level of gas concentration Safe measures have been taken (Patent Document 1).
Japanese Patent Laid-Open No. 11-311087

In Patent Document 1, a gas chromatograph is used as a means for measuring gas concentration in mud and mud samples. In the conventional gas concentration measurement (gas chromatography) by this gas chromatograph, it is necessary to release gas components (methane gas, etc.) from the mud and mud samples to make it into a gaseous state. That is, it is necessary to first remove solid components such as sand from the collected mud and mud samples, liberate the gas components from the liquid in which the gas components are dissolved, and collect the free gas.
Therefore, the separation / collection has a problem that the operation is complicated and the measurement time is long. In addition, the gas concentration in the formation cannot be measured while excavating the formation, that is, because it is a spot measurement, the gas component that springs out from the formation will be preliminarily detected and filled in the mine. It could not be said to be a sufficient gas concentration measurement method to increase safety on site.

  An object of the present invention is to provide a formation gas concentration measuring device and a formation gas concentration measuring method capable of grasping the concentration of gas components contained in the formation in a short time while excavating the formation by shield excavation or boring. There is.

  In order to solve the above-mentioned problem, the invention of the geological gas concentration measuring device according to the first aspect of the present invention provides a gas-liquid that separates a gas component from a liquid material in the geological formation or from mud containing sediments excavating the geological formation. The gas concentration is measured with respect to the target gas component among the separation unit, the gas holding unit that holds the separated gas component, and the gas component in the gas holding unit corresponding to the elapsed time after the start of measurement. Gas in the formation based on a tendency of the change in the gas concentration in the gas holding unit determined from the relationship between the gas concentration measuring unit, the gas concentration measured by the gas concentration measuring unit, and the elapsed time And a formation gas concentration correspondence information obtaining means for obtaining information corresponding to the concentration.

  Gas components in the formation exist as dissolved in liquid matter (groundwater, hot spring water, etc.) in the formation, as they are adsorbed on the earth and sand and dispersed in the formation, and as free gas reservoirs in the formation There are some cases. In the formation gas concentration measuring apparatus according to this aspect, the gas component dissolved in the liquid material, the gas component dissolved in muddy water, or the free gas is dispersed as bubbles in the liquid material or muddy water. In this state, the concentration of the gas component is measured.

  According to this aspect, the gas component separated in the gas-liquid separation unit directly from the liquid material in the formation or the mud containing the sediment excavated in the formation is held in the gas holding unit, and corresponds to the elapsed time after the start of measurement. The gas in the formation is measured based on the tendency of the change in the gas concentration in the gas holding unit determined from the relationship between the measured gas concentration and the elapsed time, by measuring the gas concentration of the gas component in the gas holding unit Since the information corresponding to the concentration is obtained, it is possible to obtain the effect that the information corresponding to the concentration of the gas component contained in the formation can be grasped in a short time while excavating the formation.

The reason why the effect is obtained will be described in detail below.
The gas component contained in the liquid material or the muddy water passes through the gas-liquid separation unit and is held in the gas holding unit. The gas component continues to pass through the gas-liquid separation unit until the concentration of the gas component held in the gas holding unit and the concentration of the gas component contained in the liquid or mud reach equilibrium. The concentration of the gas component in the holding part continues to increase. And in the state which reached the said equilibrium, the gas concentration in the said gas holding | maintenance part becomes the same as the density | concentration of the gas component contained in the said liquid substance or the said muddy water. Therefore, if the gas concentration of the target gas component in the gas holding part is measured in this state, the measurement result is the concentration of the gas component contained in the liquid material or the muddy water.

  However, the time to reach the equilibrium may take a long time of several tens to hundreds of minutes when a gas-liquid separation unit such as a gas-liquid separation membrane is used. When the liquid subject to gas-liquid separation tends to clog the gas-liquid separation film, such as mud containing earth and sand excavated from the formation, it takes a long time to reach equilibrium.

  After starting the separation in the gas-liquid separation unit, the present inventors gradually increase the gas concentration in the gas holding unit measured in the gas concentration measurement unit and reach equilibrium after several tens to hundreds of minutes. However, it has been found that the tendency of the change in the gas concentration between a few minutes to a few tens of minutes after the start of measurement has a certain correlation with the gas concentration in the gas holding unit in the state where the equilibrium is finally reached. did. That is, it has been found that the gas concentration in the state where the equilibrium is reached can be obtained from the tendency of the change in the gas concentration in the gas holding part within a few minutes to a few dozen minutes after the start of measurement.

  According to this aspect, by specifying the correlation in advance, the formation gas concentration correspondence information determining unit can shorten the number of minutes from the start of the measurement by waiting for a long time until the equilibrium is reached. Based on the tendency of the change in the gas concentration over time, it is possible to determine the gas concentration of the target gas component in the gas holding portion in the state where the equilibrium has been reached, and while excavating the formation, The effect of being able to grasp information corresponding to the gas concentration in a short time is obtained.

  The “information corresponding to the gas concentration in the formation” includes, in addition to the gas concentration of the target gas, a graph or other display that can determine whether the gas concentration of the target gas exceeds a predetermined gas concentration. Includes information.

  The invention of the formation gas concentration measuring apparatus according to the second aspect of the present invention is characterized in that, in the first aspect, the target gas component is a combustible gas.

  According to this aspect, in addition to the same effects as those of the first aspect, flammable gases such as methane, ethane, propane, natural gas, carbon monoxide, and hydrogen sulfide are measured as target gas components. It is possible to increase the safety at the construction site by predicting the risk of gas filling the mine.

  According to a third aspect of the present invention, there is provided the formation gas concentration measuring device according to the first aspect or the second aspect, wherein the formation gas concentration correspondence information obtaining means excavates the liquid matter in the formation or the formation. The muddy water containing the earth and sand is divided into a plurality of types corresponding to the degree of clogging with respect to the gas-liquid separation unit, and correction processing corresponding to each type is performed to obtain the information. Is.

  The time until the concentration of the gas component held in the gas holding unit and the concentration of the gas component contained in the liquid or mud reaches equilibrium in the first aspect is the same gas concentration. However, it varies depending on the state of the liquid material or the muddy water. For example, if it contains a lot of fine particles that clog the gas-liquid separation part, it changes in a longer direction. That is, the tendency of the gas concentration change in the short time after the start of measurement is smaller in the kind of mud that is easily clogged even at the same gas concentration.

  According to this aspect, in addition to the same effects as those in the first aspect or the second aspect, the formation gas concentration correspondence information obtaining means includes a liquid material in the formation or mud containing the sediment excavated from the formation. Since it is divided into multiple types corresponding to the state of liquid or muddy water (degree of clogging of the gas-liquid separation part), and correction processing according to each type is performed to obtain information on formation gas concentration correspondence, the formation being excavated The information corresponding to the gas concentration contained in can be obtained more accurately.

  According to a fourth aspect of the present invention, there is provided the formation gas concentration measuring device according to any one of the first to third aspects, wherein an opening is provided in the transfer pipe for transferring the liquid material or the muddy water. And when the liquid material or muddy water is transferred from the upstream to the downstream in the transfer pipe, the liquid material or the muddy water is configured to come into contact with the gas-liquid separation portion through the opening. Features.

  According to this aspect, in addition to the same effects as any one of the first aspect to the third aspect, it circulates in the transfer pipe for transferring the liquid material in the formation or the mud containing the sediment excavated from the formation. The gas concentration of the liquid or mud water to be measured can be measured. At this time, the gas-liquid separation unit is provided with an opening in the transfer pipe, and when the liquid or mud is transferred from upstream to downstream in the transfer pipe, the liquid or Since the muddy water is configured to come into contact with the gas-liquid separator, the gas concentration in the liquid material or the muddy water flowing through the transfer pipe can be measured efficiently and continuously.

The invention of the formation gas concentration measuring method according to the fifth aspect of the present invention is to separate the gas component from the liquid material in the formation or from the mud containing the earth and sand excavated from the formation by a gas-liquid separator. The gas component is held in the gas holding unit, the gas concentration is measured with respect to the target gas component among the gas components in the gas holding unit corresponding to the elapsed time after the start of measurement, and the measured gas Information corresponding to the gas concentration in the formation is obtained based on the tendency of the change in the gas concentration in the gas holding portion determined from the relationship between the concentration and the elapsed time.
According to this aspect, the same effect as the first aspect can be obtained.

  ADVANTAGE OF THE INVENTION According to this invention, the density | concentration of the gas component contained in a formation can be grasped | ascertained for a short time, performing the formation of the formation by shield excavation or boring.

<Example 1>
FIG. 1 is a diagram showing a formation gas concentration measuring apparatus according to an embodiment of the present invention.

  As shown in FIG. 1, the formation gas concentration measurement apparatus 1 according to the present invention includes a gas-liquid separation unit 2, a gas holding unit 3, a gas concentration measurement unit 4, and formation gas concentration correspondence information obtaining means 5. It is configured. The formation gas concentration correspondence information obtaining means 5 is connected to the gas concentration measuring unit 4 through a cable 6.

  The gas-liquid separation unit 2 separates a gas component from a liquid material in the formation or muddy water containing earth and sand excavated from the formation. As the gas-liquid separation unit 2, a gas-liquid separation membrane that allows gas to pass but does not allow liquid to pass can be used. By using the gas-liquid separation membrane, only the gas components in the mud containing the liquid material in the formation or the mud that has excavated the formation pass through the gas-liquid separation membrane, so the gas component is separated from the liquid or the mud. And held in the gas holding unit 3.

  Here, the gas component passes through the gas-liquid separation unit 2 until the concentration of the gas component held in the gas holding unit 3 and the concentration of the gas component contained in the liquid material or the muddy water reach an equilibrium. It continues to pass and the concentration of the gas component in the gas holding unit 3 continues to increase. When the equilibrium is reached, the gas concentration in the gas holding unit 3 becomes the same as the concentration of the gas component contained in the liquid material or the muddy water. Accordingly, if the gas concentration measuring unit 4 measures the gas concentration of the target gas component in the gas holding unit 3 in this state, the measurement result is the concentration of the gas component contained in the liquid material or the muddy water. It will be.

  However, the time to reach the equilibrium may take a long time of several tens to hundreds of minutes when the gas-liquid separation unit 2 such as a gas-liquid separation membrane is used. When the liquid subject to gas-liquid separation tends to clog the gas-liquid separation film, such as mud containing earth and sand excavated from the formation, it takes a long time to reach equilibrium.

  In the formation gas concentration measuring apparatus 1 according to the present invention, after the gas-liquid separation unit 2 starts separation, the gas concentration in the gas holding unit 3 measured by the gas concentration measurement unit 4 gradually increases, and several tens of times. Equilibrium is reached after a few hundred minutes from the minute, but the tendency of the change in the gas concentration between a few minutes and a few dozen minutes after the start of measurement is finally in the gas holding unit 3 in the state where the equilibrium is reached. Of the gas concentration in the gas holding unit 3 during several minutes to ten and several minutes after the start of measurement by the formation gas concentration correspondence information obtaining means 5 based on having a certain correlation with the gas concentration of From this, the gas concentration in the state of reaching the equilibrium can be obtained.

  By specifying the correlation in advance, the formation of the gas concentration in a short time of several minutes to ten and several minutes after the start of measurement by the formation gas concentration correspondence information obtaining means 5 without waiting for a long time until the equilibrium is reached. Based on the tendency of the change, it becomes possible to obtain the gas concentration of the target gas component in the gas holding unit 3 in the state where the equilibrium is reached, so that the gas concentration in the formation can be obtained while excavating the formation. An effect that the corresponding information can be grasped in a short time can be obtained.

  The “information corresponding to the gas concentration in the formation” includes, in addition to the gas concentration of the target gas, a graph or other display that can determine whether the gas concentration of the target gas exceeds a predetermined gas concentration. Includes information.

  The gas concentration measuring unit 4 measures the gas concentration with respect to a target gas component among the gas components in the gas holding unit 3 corresponding to the elapsed time after the start of measurement. Examples of the target gas measured by the gas concentration measuring unit 4 include flammable gases such as methane, ethane, propane, natural gas, carbon monoxide, and hydrogen sulfide. As the gas concentration measuring unit 4, a known gas concentration measuring device using a semiconductor sensor, a contact combustion sensor, or the like can be used. A known gas sensor constituted by the gas-liquid separation unit 2, the gas holding unit 3, and the gas concentration measurement unit 4 can also be used. For example, as the methane gas sensor, a METS methane sensor (manufactured by Frantech) can be used.

  By measuring the combustible gas such as methane gas as the target gas in the gas concentration measuring unit 4, it is possible to predict the risk that the combustible gas will fill the mine and improve the safety at the construction site.

<Example 2>
Next, a formation gas concentration measuring apparatus according to another embodiment of the present invention will be described. In this embodiment, in the formation gas concentration measuring apparatus 1 described in Embodiment 1, the formation gas concentration correspondence information obtaining means 5 is configured to use the liquid material in the formation or the mud containing the earth and sand excavated from the formation. The information is divided into a plurality of types corresponding to the degree of clogging of the separation unit, and correction processing corresponding to each type is performed to obtain the information. Since the configuration including the gas-liquid separation unit 2, the gas holding unit 3, the gas concentration measurement unit 4, and the formation gas concentration correspondence information obtaining unit 5 is the same as that of the first embodiment, the description thereof is omitted.

  The time required until the concentration of the gas component held in the gas holding unit and the concentration of the gas component contained in the liquid or mud reaches equilibrium in the first embodiment described above is the same gas concentration. However, it varies depending on the state of the liquid material or the muddy water. For example, if it contains a lot of fine particles that clog the gas-liquid separation part, it changes in a longer direction. That is, the tendency of the gas concentration change in the short time after the start of measurement is smaller in the kind of mud that is easily clogged even at the same gas concentration. An experimental example specifically showing this will be shown below.

  Using the gas concentration measurement experimental apparatus 10 in FIG. 2, methane gas was injected into fresh water, clay mud for civil engineering (rough mud of coarse mud particles), and bentonite mud (fine mud of fine mud particles) so as to have a constant concentration, respectively. An experiment was conducted to measure the methane gas concentration using a sensor (methane gas sensor 11 in FIG. 2). The gas concentration measurement experimental apparatus 10 circulates water into which a predetermined amount of methane gas has been injected, civil clay mud water, and bentonite mud water by a circulation pump 15 (the arrow in the gas concentration measurement experimental apparatus 10 in FIG. The liquid is configured to come into contact with the gas-liquid separator 12 of the methane gas sensor 11 when each liquid flows from the upstream to the downstream of the circulation system. Elapsed time until the measured methane gas value by the methane gas sensor 11 reaches the methane gas concentration corresponding to the actually injected methane gas amount for each liquid (fresh water, clay mud for civil engineering, bentonite muddy water) injected with a predetermined amount of methane gas Are shown in FIG. 3 (Shimizu), FIG. 4 (Clay mud for civil engineering), and FIG. 5 (Bentonite mud).

  When methane gas is injected into fresh water (Fig. 3) so as to be 90 µmol / liter, it takes about 100 minutes to measure the methane gas concentration, but also clay mud for civil engineering (Fig. 3) in which methane gas is injected so as to be 90 µmol / liter. 4) takes about 180 minutes. Civil clay mud is a mud of relatively coarse mud particles. Furthermore, in bentonite mud water (Fig. 5), which is mud particles finer than civil clay clay mud, 90 μmol / liter of methane gas is not measured after 200 minutes, and accurate methane gas concentration measurement takes about 250 minutes. The result seems to be.

  The elapsed time for measuring the methane gas concentration in civil engineering clay mud and bentonite mud is longer than the elapsed time for measuring methane gas concentration in fresh water. It is thought that this is because the gas-liquid separation unit 2 is clogged by the contained mud particles. And since the mud particles contained in the bentonite mud are mud particles finer than the mud particles contained in the clay mud for civil engineering, the gas-liquid separation unit 2 is more likely to be clogged, so that the elapsed time becomes longer. Conceivable.

  As described above, the time to measure the gas concentration of the liquid to be measured, that is, the liquid in the formation or the mud containing the earth and sand excavated from the formation changes depending on the degree of clogging of the gas-liquid separation unit 2. . In the present embodiment, the information obtained by the formation gas concentration correspondence information obtaining means 5 is configured to perform a correction process corresponding to the type corresponding to the degree of clogging of the liquid substance or the muddy water gas-liquid separation unit 2. Therefore, the gas concentration contained in the formation during excavation can be estimated more accurately.

<Example 3>
FIG. 6 is a conceptual diagram when the formation gas concentration measuring device according to the present invention is installed in the shield mine 20. FIG. 7 is a view showing an example in which the formation gas concentration measuring device according to the present invention is installed in the mud pipe of the mud shield excavator 21.

  As shown in FIG. 6, when excavating a tunnel or the like using the mud shield excavator 21, mud material such as clay, bentonite, and water added to the excavated earth and sand is sent by the mud pipe 22, The mud shield shield excavator 21 can control the amount of excavation and soil discharge while preventing the collapse of the excavated part against the pressure of cut soil and groundwater by the imperviousness and plastic fluidity of the mud mixed with mud. It is carried out by digging while measuring the balance. The discharged soil (the muddy water containing the earth and sand excavated from the formation) is transferred by the exhaust mud pipe 23 (the transfer pipe for transferring the muddy water including the earth and sand excavated from the formation) and discharged into and out of the shield mine 20.

  By providing the formation gas concentration measuring apparatus 1 according to the present invention in the mud pipe 23, the concentration of the gas component contained in the formation that is excavating can be measured in real time. The formation gas concentration correspondence information obtaining means 5 of the formation gas concentration measuring device 1 is provided in a management building outside the shield mine 20, for example, when a gas concentration rises, a signal for alerting the inside of the mine or excavation It is desirable to take measures such as canceling work. When sufficient space for installing the formation gas concentration correspondence information obtaining means 5 in the shield mine 20 can be secured, the shield mine 20 can also be provided in the shield mine 20.

  As shown in FIG. 7, the formation gas concentration measuring apparatus 1 is provided with an opening 24 in the mud pipe 23, and when the mud water 25 is transferred from the upstream to the downstream in the mud pipe 23, the opening 24 It is desirable that the muddy water 25 is configured to come into contact with the gas-liquid separation unit 2 via As a result, the gas concentration in the mud water 25 flowing through the mud pipe 23 can be efficiently and continuously measured. Further, the discharge valve 27 discharges the muddy water 25 in the drainage pipe 23 when discharging bubbles accumulated around the gas-liquid separation unit 2 or removing the formation gas concentration measuring device 1 provided in the opening 24. Can be used for

  Furthermore, it is desirable to provide a gravel prevention plate 26 in the opening 24 as shown in FIG. The gravel prevention plate 26 can prevent the gravel from accumulating near the gas-liquid separator 2. 9 is a plan view of the gravel prevention plate 26, and FIG. 10 is a cross-sectional view taken along line AA of FIG.

  The gravel prevention plate 26 is provided with a gravel prevention hole 28 for removing large gravel. As shown in FIG. 8, the gravel prevention hole 28 is preferably provided in a shape that allows the muddy water passing through the gravel prevention hole 28 to easily form a flow in contact with the gas-liquid separation unit 2. Further, since the cross section of the gravel prevention hole 28 (AA cross section in FIG. 9) is formed as shown in FIG. 10, the muddy water 25 is efficiently separated from the mud pipe 23 side while preventing the gravel. It can be sent to the part 2 side.

  INDUSTRIAL APPLICABILITY The present invention is effective as a formation gas concentration measuring apparatus and a formation gas concentration measurement method for measuring the concentration of gas components contained in the formation while performing excavation of the formation by shield excavation or boring.

It is a figure which shows the formation gas concentration measuring apparatus which concerns on embodiment of this invention. This is an experimental device for measuring the concentration of methane gas contained in a liquid. It is a figure which shows the elapsed time which the methane gas concentration measurement contained in fresh water requires. It is a figure which shows the elapsed time which the methane gas concentration measurement contained in the clay mud for civil engineering requires. It is a figure which shows the elapsed time required for the measurement of the methane gas concentration contained in bentonite mud. It is a conceptual diagram in the case of installing the formation gas concentration measuring apparatus which concerns on this invention in a shield mine. It is a figure which shows an example in the case of installing the formation gas density | concentration measuring apparatus which concerns on this invention in the mud pipe of a mud shield excavator. It is a figure which shows another example in the case of installing the formation gas density | concentration measuring apparatus which concerns on this invention in the mud pipe of a mud shield excavator. It is a top view of the gravel prevention plate 26. FIG. It is AA sectional drawing of the gravel prevention plate 26 of FIG.

Explanation of symbols

1 Geological gas concentration measuring device, 2 Gas-liquid separation unit, 3 Gas holding unit,
4 Gas concentration measurement section, 5 Geological gas concentration correspondence information obtaining means, 6 Cable,
10 gas concentration measurement experiment equipment, 11 methane gas sensor,
12 gas-liquid separation unit, 13 gas holding unit, 14 gas concentration measuring unit,
15 Circulation pump,
20 shield mine, 21 mud shield excavator,
22 mud pipe, 23 drain mud pipe, 24 opening,
25 muddy water, 26 gravel prevention plate,
27 Discharge valve, 28 Gravel prevention hole

Claims (4)

A gas-liquid separation unit that includes a gas-liquid separation membrane that allows gas to pass therethrough and that does not allow liquid to pass through the gas-liquid separation membrane, and that separates gas components from liquid matter in the formation or from mud containing sediments excavating the formation; ,
A gas holding unit for holding the separated gas component;
A gas concentration measuring unit for measuring a gas concentration with respect to a target gas component among the gas components in the gas holding unit corresponding to an elapsed time after the start of measurement;
Information corresponding to the gas concentration in the formation is obtained based on the tendency of the gas concentration change in the gas holding unit determined from the relationship between the gas concentration measured by the gas concentration measuring unit and the elapsed time. A means for determining information on the formation gas concentration correspondence,
The formation gas concentration correspondence information obtaining means includes a plurality of types of liquid matter in the formation or muddy water containing sediment excavated from the formation corresponding to the degree of clogging of the gas-liquid separation membrane of the gas-liquid separation unit. Divided, correction processing corresponding to each type is made and configured to obtain the information,
An opening is provided in a transfer pipe for transferring the liquid material or the muddy water, and a space communicating through the opening is provided, and the gas-liquid separation membrane of the gas-liquid separation unit is disposed in the space. And when the liquid or muddy water is transferred from upstream to downstream in the transfer pipe, the liquid or muddy water flows into the space through the opening, and then the gas-liquid separation unit A geological gas concentration measuring apparatus configured to come into contact with the gas-liquid separation membrane and return to the transfer pipe again.   The formation gas concentration measuring device according to claim 1, wherein a gravel prevention plate for preventing gravel from entering from the transfer pipe side to the gas-liquid separation membrane side is provided in the opening. A geological gas concentration measurement device.   The formation gas concentration measuring apparatus according to claim 1 or 2, wherein the target gas component is a combustible gas. An opening is provided in a transfer pipe for transferring muddy water containing earth and sand excavated from the liquid material in the formation, a space communicating through the opening is provided , gas is passed through the space, and the liquid is supplied. A gas-liquid separation membrane that does not pass through the gas-liquid separation membrane , wherein the gas-liquid separation membrane separates a gas component from a liquid material in the formation or from mud containing earth and sand excavated in the formation. When the liquid or muddy water is transferred from upstream to downstream in the transfer pipe, the liquid or muddy water flows into the space through the opening, and In contact with the gas-liquid separation membrane, return to the transfer pipe again,
Gas components are separated from the liquid material in the formation or from the muddy water containing earth and sand excavated from the formation by the gas-liquid separation membrane of the gas-liquid separation unit,
Holding the separated gas component in a gas holding unit;
Of the gas components in the gas holding unit corresponding to the elapsed time after the start of measurement, measure the gas concentration for the target gas component,
Based on the tendency of change in the gas concentration in the gas holding portion determined from the relationship between the measured gas concentration and the elapsed time, information corresponding to the gas concentration in the formation is obtained, and in the formation Muddy water containing liquid material or earth and sand excavated from the formation is divided into a plurality of types corresponding to the degree of clogging of the gas-liquid separation membrane of the gas-liquid separation unit, and correction processing corresponding to each type is made and the information The formation gas concentration measuring method characterized by calculating | requiring.

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