JP3348028B2 - Volcanic phreatic explosion prediction system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a system for predicting a volcanic phreatic explosion. The present invention relates to a system for continuously monitoring a plurality of gas components contained in an object erupting from the ground to change the gas amount of a predetermined gas or a predetermined amount. The present invention relates to a volcanic phreatic explosion prediction system for estimating signs of a phreatic explosion from changes in the component ratios of a plurality of gases.

[0002]

2. Description of the Related Art The state of volcanic activity at that time is estimated from changes in chemical components contained in eruptive products, especially volcanic gas and volcanic spring water, etc., associated with volcanic activity. Many geochemical researchers are examining whether this is possible.

[0003] A phreatic explosion is an explosive eruption caused by high-temperature, high-pressure steam, and the ejecta is composed of fragments of the constituent materials of the old mountainous body, without the substances derived from the new magma. On the other hand, a phreatomagmatic explosion (also referred to as a phreatomagmatic explosion) is an explosive eruption that occurs when surface water or groundwater comes in contact with high-temperature magma, and the ejecta contains substances derived from new magma. The present invention makes it possible to predict the above-mentioned volcanic phreatic explosion.

[0004]

By the way, in order to investigate the change of chemical components contained in volcanic gas and volcanic spring water, it is necessary to set aside a danger zone that is remote and may not explode at any time. Measuring equipment must be brought in. In addition, since a continuous investigation is required, much time and effort are required. Further, for example, when building a road or a structure in an area where there is a danger of a volcanic phreatic explosion, many people will stay in the danger area.

[0005] In such a case, it is necessary to detect the signs of the explosion as soon as possible, and to take measures to evacuate and keep out of the area early. However, there is a problem that it is difficult to continuously observe the underground over a wide area.

The present invention has been made in order to solve such a problem. The present invention is to continuously monitor the amount of gas contained in an object erupting from the ground, the component ratio of a plurality of predetermined gases, etc. It is an object of the present invention to provide a system capable of predicting a steam explosion from a change in an amount or a component ratio of a plurality of predetermined gases.

[0007]

[0008]

According to a second aspect of the present invention, in the volcanic phreatic explosion prediction system, at least one well provided in a predetermined area and a plurality of gas components contained in an object ejected from the well are continuously analyzed. Gas analyzing means for converting the concentration of the gas component into an electric signal, recording means for recording each value analyzed by the gas analyzing means, display means for displaying at least one of the recorded data, Calculating means for calculating an average value of data obtained at predetermined time intervals, comparing the latest average value with the immediately preceding average value and calculating the difference between the latest average value and the previous average value and the latest average value. A warning is issued when at least one of them exceeds a predetermined level, and the well where the warning is issued
Display the data of the gas amount of the past retroactively
Along with the data on the gas volume of other wells
It is characterized in that it is configured to display a trend .

According to a third aspect of the present invention, in the volcanic phreatic explosion prediction system, at least one well provided in a predetermined area and a plurality of gas components contained in an object ejected from the well are continuously analyzed. Gas analyzing means for converting the concentration of the gas component into an electric signal, recording means for recording each value analyzed by the gas analyzing means, and calculating a ratio of at least two gas components of the recorded data. The arithmetic means and an alarm are issued when the ratio exceeds a predetermined level, and the well of which the alarm is issued is provided.
If you display the gas amount data retroactively in the past,
In both cases, the data on the gas volume of other wells were traced back to the past.
It is characterized in that it is configured to render .

According to a fourth aspect of the present invention, in the volcanic vapor explosion prediction system according to the third aspect, the gas component ratios are hydrogen gas (H2) and nitrogen gas (N2) and / or sulfur dioxide (SO2) and hydrogen sulfide (H2S ).

[0012] In a fifth aspect is the volcanic steam explosion prediction system according to any one of claims 1, 2, 3, characterized in that the gas analyzing means is a process gas chromatograph.

In claim 6 , any one of claims 1 to 3
In the volcanic phreatic explosion prediction system described in the above, the object ejected from the well is temporarily conveyed to a separator for separating water vapor and liquid, and the water vapor of the separator is conveyed to the process gas chromatography by a pipe having a heating means. It is characterized by having done.

According to a seventh aspect of the present invention, in the volcanic phreatic explosion prediction system according to the sixth aspect , the pipe is made of 100 vol.
It is characterized by being heated to about 120 ° C. In claim 8, in volcanic steam explosion prediction system according to any one of claims 1, 2, 3, the gas analysis means, characterized in that a process gas chromatography and process ion chromatography.

According to a ninth aspect of the present invention, in the volcanic vapor explosion prediction system according to the eighth aspect , the process ion chromatography includes a first process ion chromatography for analyzing a liquid component in the separator and a component in a state where the water vapor is liquefied. The component included in the ejected object is estimated based on the component analyzed by the second process ion chromatography to be analyzed. According to a tenth aspect , in the volcanic phreatic explosion prediction system according to the ninth aspect , the water vapor is bubbled with a liquid maintained at a pH of 9 or more, and the liquid after the bubbling is analyzed by the second process ion chromatography. And In claim 11, in volcanic steam explosion prediction system according to any one of claims 1, 2, 3, the arithmetic means were recorded via the modem data, at least one of the calculation results and alarms at least It is characterized by having a function of transmitting to a remote place.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the drawings. FIG. 5 is a plan view showing a state where a well is provided in an area where there is a risk of volcanic phreatic explosion, which is a premise of the present invention. In the figure, a portion indicated by A shows the area that might human intrude or residence, a portion indicated by B represents the area that can undergo the damage if the vapor explosion has occurred.

The wells indicated by (a) to (e) are, for example, wells having a diameter of about 50 mm and a depth of about 100 to 500 m, and have a predetermined angle (for example, 40 to 70) with respect to a horizontal plane.
Degree): It is provided in the area A or the area B at an angle.

FIG. 1 is a schematic configuration diagram showing an example of an embodiment of the present invention. In the figure, reference numeral 100 denotes wells (a) to (e) shown in FIG. Reference numeral 101 denotes a site hut in which a gas analyzer (process gas chromatography, hereinafter referred to as gas chromatography, process ion chromatography, hereinafter referred to as ion chromatography, etc.) is stored. It can be monitored.

The gas analyzer may be provided in each well, and the ejected material from each well may be transported to one location and analyzed while switching. However, in the method of performing analysis while switching, it is difficult to use a technique for preventing a change in composition during transportation or contamination (foreign matter) during switching, and requires expensive equipment.

Reference numeral 102 denotes a recorder housing panel 103, an observation data monitoring device 104 having a display means 105, and a printer 1
06, etc., in the site office,
2 is provided in a region A shown in FIG. Recorder storage panel 1
03 is also provided with a signal input device (not shown).
The results of gas analysis from each well are displayed for each well or recorded on a recording medium such as recording paper.

The observation data monitoring device (computing means) 104 displays the result of gas analysis from each well for each well.
When the gas amount preset for each well exceeds the set value, a comparison operation is performed and an alarm is issued, and the data of the gas analysis value of the well for which the alarm was issued is stored in the past. Display the trend retroactively. Further, with respect to the other wells, the data of the components of the other wells at that time can be retroactively displayed in the past.

The calculating means 104 calls the recorded data, calculates an average value for each predetermined time (for example, 1 hour, 12 hours, 24 hours, etc.), and calculates the average value for each hour and the latest average value for each hour. The hourly average value is compared to calculate the difference, or when the latest average value exceeds a predetermined level or when the difference between the previous average value and the latest average value exceeds a predetermined level. It is configured to issue an alarm at times.

The contents displayed on the display unit 105 of the calculating means and the measurement data of the calculating means 104 are transmitted to the modem 107.
a to 107d and can be transmitted to remote data monitoring devices 102a and 102b at remote locations via the NTT line, and can be displayed on display means 105a and 105b, and the contents can be displayed by printers 106a and 105b as necessary. Can be output on recording paper.

Although not shown in the figure, the contents of the arithmetic unit 104 can be displayed on a client personal computer via a mobile phone or a mobile device.

According to the known literature, SO ₂ and H ₂ cannot be observed in a normal case where there is no danger of steam explosion. As the danger of explosion approaches, SO ₂ and H ₂ are generated, and SO ₂ / H ₂ S
But 0.5 to 1.0 or more, H ₂ / N ₂ is to be able to estimate that the approaching eruption time Once you become 0.2 or more.

Although the composition of the volcanic gas varies depending on the place (volcano), in the case of a phreatic explosion, almost 100% is H ₂ O, and about 0.5 to 5% of other components are contained therein. The components that can be estimated are H ₂ , N ₂ , CH ₄ , CO ₂ , H
₂ S, SO ₂ , HCl, HF and the like. CH ₄ ,
CO ₂ , H ₂ S, SO ₂ , HCl and HF are H ₂ O at room temperature and pressure.
Dissolves in water when becomes liquid.

FIG. 2 is a block diagram showing a first embodiment of gas analysis. In the figure, the jet gas is guided to a separator 1 and separated into a gas phase and a liquid phase. The liquid phase is sent to the first ion chromatography 2. The first ion chroma 2 is SO ₃ ^2- , S
The O ₄ ^2- component is detected and an electric signal corresponding to the concentration is output to the recording / calculation / display means 6.

On the other hand, the gas phase is branched in two directions, and one is dissolved in pure water to carry out bubbling in an alkali solution tank 3 maintained at about pH 7 to pH 10 (preferably pH 9). By this bubbling, S,
CO ₂ and Cl dissolve. The second ion chroma 4 analyzes the components of S ₂ O ₃ ²⁻ and S ²⁻ from the alkaline solution in which these are dissolved, and records / calculates / displays an electric signal corresponding to the concentration.
Output to

The other branched gas phase is sent to a gas chromatograph 5 where the components of H ₂ , N ₂ and O ₂ are analyzed, and the gas chromatograph 5 sends an electric signal corresponding to the concentration to a recording / calculating / display means 6. Output.

The recording / arithmetic / display means 6 records the transmitted signals, and calculates H ₂ / N ₂ from these values.
And SO ₂ / H ₂ S is calculated. Then, the display unit 6a displays the concentration of at least one of the predetermined gases, the calculation result, and the like. Further, each gas concentration or the calculation result is compared with a predetermined value, and an alarm is issued if the predetermined value is exceeded.

However, in the above configuration, SO ₂ , H ₂
Since S is not directly measured, it must be estimated by calculation from the amount of each gas, and there is a problem in reliability.

FIG. 3 is a block diagram showing a second embodiment of the gas analyzer. In the figure, the ejected matter (steam) from the well 100 is introduced into the separator 1 and separated into liquid and steam. In that case, the vapor is bubbled into the liquid from near below the separator 1.

An alkaline solution is injected into the solution in the separator 1 from the alkaline solution tank 3, and the pH is measured by the pH meter 10.
It is controlled so as to be about H7 to pH10 (preferably pH9). Therefore, this liquid contains CH ₄ , CO ₂ , H ₂ S, SO ₂ , and HC which are presumed to be contained in the ejecta.
1, HF dissolves sufficiently.

Then, the liquid in the separator is introduced into the gas chroma 5 via the pump 11. Although omitted in the drawing, the liquid is vaporized by the heating means and then at least H ₂ S,
The component of SO ₂ gas is measured. The gas chromatograph 5a measures the components of H ₂ and N ₂ gases that are not dissolved in the alkaline solution. In the measurement method shown in FIG. 3, since the component is separated into a component soluble in water and a component not soluble in the measurement, the calculation is facilitated and the measurement accuracy can be improved.

However, the method shown in FIG. 3 separates the ejected gas components into liquid and water vapor and measures them separately, so there is a problem in their consistency. FIG. 4 shows a third embodiment, in which the water vapor separated by the separator 1 is gasified and measured.

In the configuration shown in FIGS. 2 and 3, the separator 1
The piping between the gas chromato and the gas chroma
No extreme heating measures have been taken. As a result, steam
It liquefies before it reaches the skull 5,5a,
H that easily melts in water_TwoS, SO _TwoAccurate measurement of gas components
Can not do it. Therefore, components that are easily melted in water
Components that are hardly soluble in water were separately measured.

Therefore, in this embodiment, the pipe 15 with a heating means for carrying water vapor from the separator 1 to the gas chromatograph 5 is heated to about 100 to 120 ° C. According to such a method, all the gas components contained in the water vapor are supplied to the gas chromatography side in a gaseous state, so that there is no need to calculate the ratio of the components as compared with the embodiment of FIGS. Further, the entire apparatus can be simplified, and the system can be configured at low cost.

It should be noted that, even if the amount of a certain component exceeds the set value and a warning is issued, this does not immediately lead to an explosion. For example, when issuing an evacuation advisory or evacuation order, judgment is made using various expertise.

The foregoing description of the present invention has been presented by way of illustration and example only and in certain preferred embodiments. Accordingly, the present invention has many modifications, without departing from its essence,
It will be apparent to those skilled in the art that variations can be made. For example,
In some cases, the amount and content of the ejected material from the well may change continuously, and in some cases it may be exhausted. In such a case, it is necessary to change the set value of the alarm according to the state.

The configuration of the apparatus is not limited to those shown in FIGS. 1 and 2, and can be changed according to the state. Also, the ejected material from the well does not necessarily need to be separated by a separator, and may be directly led to gas chromatography depending on conditions. The scope of the present invention, which is defined by the description in the appended claims, is intended to cover alterations and modifications within the scope.

[0041]

As described above, according to the present invention,
At least one well provided in a predetermined area, gas analyzing means for continuously analyzing a plurality of gas components contained in an object ejected from the well, and converting the concentration of each gas component into an electric signal, Recording means for recording each of the values analyzed by the gas analysis means, display means for displaying at least one of the recorded data, at least one of the recorded gas amounts and a predetermined value for the gas amount Calculation means for performing a comparison operation between the well and the well in which the warning is issued when the gas amount exceeds a predetermined value.
Display the data of the gas amount of the past retroactively
Along with the data on the gas volume of other wells
Since the system is configured to display a trend, a system capable of predicting a volcanic phreatic explosion can be realized.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing an example of an embodiment of the present invention.

FIG. 2 is a schematic configuration diagram showing another example of the embodiment of the present invention.

FIG. 3 is a schematic configuration diagram showing another example of the embodiment of the present invention.

FIG. 4 is a schematic configuration diagram showing another example of the embodiment of the present invention.

FIG. 5 is a plan view showing a state where a well is provided in an area where there is a risk of volcanic phreatic explosion.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Separator 2 1st process ion gas chromatograph 3 Alkaline liquid tank 4 2nd process ion gas chromatograph 5 Process gas chromatograph 6 Recording / calculation / display means 10 pH meter 11 Pump 12 Valve 100 Well 101 Gas analyzer 102 Field office 102a, 102b Remote data monitoring device 103 Recorder storage panel 104 Observation data monitoring device (arithmetic means) 105 Display means 106 Printer 107 Modem

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Ken Murayama 2-9-132 Nakamachi, Musashino-shi, Tokyo Yokogawa Electric Corporation (72) Inventor Yoshio Oki 2-9-132 Nakamachi, Musashino-shi, Tokyo Next to Inside Kawa Electric Co., Ltd. (72) Inventor Tadaaki Nakao 2-9-132 Nakamachi, Musashino City, Tokyo Yokogawa Electric Co., Ltd. (56) References JP-A-6-201837 (JP, A) JP-A 64- 66554 (JP, A) JP-A-62-118287 (JP, A) MARINI L, Application of geochemistry to volcanic exploration, Geochemistry applied to volcanic surveyilance, Proc. 400 (58) Field surveyed (Int.Cl. ⁷ , DB name) G01V 1/00 G01V 1/40 G01V 9/0 0

Claims (11)

(57) [Claims] 1. A gas for continuously analyzing at least one well provided in a predetermined area and a plurality of gas components contained in an object ejected from the well, and converting the concentration of each gas component into an electric signal. Analysis means, recording means for recording each of the values analyzed by the gas analysis means, display means for displaying at least one of the recorded data, at least one of the recorded gas amount and the gas amount Calculating means for comparing and calculating a predetermined value, and when the gas amount exceeds a predetermined value, an alarm is issued, and the data of the gas amount of the well where the alarm is issued is retroactively traced back. A volcanic phreatic explosion prediction system characterized by displaying a trend and displaying the data of the gas amount of other wells retroactively in the past. 2. A gas for continuously analyzing at least one well provided in a predetermined area and a plurality of gas components contained in an object ejected from the well and converting the concentration of each gas component into an electric signal. Analysis means, recording means for recording each of the values analyzed by the gas analysis means, display means for displaying at least one of the recorded data, and calculating an average value of the recorded data at predetermined time intervals. Computing means for comparing the latest average value with the immediately preceding average value to calculate the difference, and at least one of the latest average value and the difference between the previous average value and the latest average value exceeds a predetermined level. When an alarm is issued, the gas in the well where the alarm was issued
Display the amount of data retroactively and display the trend
Table of retrospective data on the gas volume of wells
Volcanic steam explosion prediction system characterized by being configured to indicate. 3. A gas for continuously analyzing at least one well provided in a predetermined area and a plurality of gas components contained in an object ejected from the well, and converting the concentration of each gas component into an electric signal. Analyzing means, recording means for recording each value analyzed by the gas analyzing means, and calculating a ratio of at least two gas components of the recorded data .
Calculating means for generating a warning when the ratio exceeds a predetermined level, and the gas in the well where the warning is issued.
Both other and trend displays retroactively the amount of data in the past
Table of retrospective data on the gas volume of wells
Volcanic steam explosion prediction system characterized by being configured to indicate. 4. The gas component ratio is a ratio of hydrogen gas (H ₂ ) to nitrogen gas (N ₂ ) and / or sulfur dioxide (SO ₂ ) and hydrogen sulfide (H ₂ S). 3. The volcanic phreatic explosion prediction system according to 3. 5. A volcanic phreatic explosion prediction system according to claim 1, wherein the gas analyzing means is a process gas chromatography. 6. An object ejected from a well is once transported to a separator for separating water vapor and liquid, and the vapor of the separator is transported to process gas chromatography by a pipe having a heating means. Item 4. The volcanic phreatic explosion prediction system according to any one of Items 1 to 3. 7. The volcanic phreatic explosion prediction system according to claim 6, wherein the pipe is heated to about 100 to 120 ° C. 8. The volcanic phreatic explosion prediction system according to claim 1, wherein the gas analyzing means is process gas chromatography and process ion chromatography. 9. The process ion chromatography is based on a first process ion chromatography for analyzing a liquid component in a separator and a second process ion chromatography for analyzing a component in a state where water vapor is liquefied. 9. The volcanic phreatic explosion prediction system according to claim 8, wherein the contained components are estimated. 10. The volcanic vapor explosion prediction system according to claim 9, wherein the water vapor is bubbled with a liquid maintained at a pH of 9 or more, and the liquid after the bubbling is analyzed by the second process ion chromatography. 11. The apparatus according to claim 1, wherein said arithmetic means has a function of transmitting at least one of data recorded, an arithmetic result and an alarm to at least one remote place via a modem. The volcanic phreatic explosion prediction system according to any of the above.