JPH11118701A - Environmental monitoring device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a state where a substance emitted into an environment passing through detecting means, by arranging the detecting means with taking into account a diffusion extent of the substance emitted in the environment determined by a meteorological condition. SOLUTION: Fixed detecting means 1, 2, 3 for measuring meteorological data such as a concentration of a substance feared to be diffused in an environment from an emission point 5, a wind direction, a wind velocity, etc., are arranged in the periphery of the emission point 5. A movement-detecting means 4 is placed on the lee of the emission point 5 because the emitted substance is diffused between the detecting means 1 and 2 due to a wind direction 6 at the time. A distance between the detecting means, and an angle of lines connecting the emission point 5 and detecting means are set properly while a diffusion width of the substance emitted in the environment determined from meteorological conditions is taken into account. Accordingly at least one or two detecting means catches the diffusion of the emitted substance at all times under almost any meteorological conditions, thus enabling measurement of a concentration. The emitted substance never slips through between the detecting means.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an environmental monitoring apparatus, and more particularly to a factory that handles substances that may affect the environment when released into the environment in an emergency, such as a chemical factory, a nuclear plant, and a reprocessing factory. And an environment monitoring device suitable for use in a plant.

[0002]

2. Description of the Related Art Generally, a monitoring post or monitoring is performed as an environmental monitoring device in an environment to measure the environmental concentration of a substance released into the environment from a factory or a plant that handles air pollutants that may affect the environment. A detecting means for measuring the concentration, the wind direction, and the wind speed of the emission substance called a station is provided. Should any substance related to the environment be released, that is, in an emergency, it is necessary to grasp the diffusion status and concentration based on the data obtained from these detection means, evaluate the impact on the environment, and take appropriate measures. There is.

[0003] For this reason, such detection means must be appropriately arranged in the environment. Conventionally, as shown in FIG. 3, the detection means arranged around a factory or a plant has been arranged at an interval of about one point in 4 to 16 directions around an assumed emission point. In addition, the apparatus has been designed to grasp the state of diffusion from the distribution of the concentration detected by these detecting means and evaluate the effect on the environment. Japanese Unexamined Patent Publication No. 2-64437 can be mentioned as this kind of technology.

[0004]

In general, the state of diffusion of a substance released into the environment is shown in FIG. 5 as an example in the horizontal direction. Pasquill −
This can be predicted from the Gifford diagram.

[0005]

[Table 1]

[0006] The atmospheric stability required for obtaining the diffusion width from this diagram is calculated according to the Pasquill stability classification shown in Table 1.
It is determined from weather conditions such as wind speed, solar radiation, and cloudiness. Substances that diffuse into the environment by wind from the point of release spread into the environment, as schematically shown in FIG. 6, and the standard deviation of the spread width of the diffused substances is evaluated from the Pasquill-Gifford diagram. The concentration distribution of the substance released into the environment follows a normal distribution as shown in FIG.

Assuming that the standard deviation of the diffusion width at a distance r (m) from the emission point is σ (r) (m), about 95% of the spread of the diffusion material at the distance r is ± 2σ (r) and about 99%. The% section exists in a range of ± 3σ (r). FIG. 8 shows a range of ± 2σ (r) corresponding to each atmospheric stability, that is, a range of 4σ (r), considering an approximately 95% section generally used in the field of statistics.
This is a comparison of the distance between the detection means when the detection means is arranged on the circumference of the radius r in the azimuth. As shown in FIG. 8, when the atmospheric stability is A to B, it is possible to detect the spread of the substance released into the environment by the detecting means arranged in about 16 directions.

[0008] However, when the atmospheric stability is C to F, it is difficult to grasp the spread of the released substance, and it is suggested that the concentration in the environment may not be measured. That is, when the detection means is not properly arranged in the environment monitoring device, a situation in which the substance released into the environment slips between the detection means arranged in the environment and the detection means in consideration of all weather conditions. There is a concern that this may occur.

[0009]

In order to solve such a problem, the environmental monitoring device of the present invention considers the diffusion width of a substance released into the environment given by the atmospheric stability determined from the above-mentioned weather conditions. Then, the detecting means is arranged in the environment.

That is, when the distance from the emission point to the first detecting means is r (m), and the standard deviation of the diffusion width of the emission material at the distance r is σ (r) (m), the emission point is defined as Of points at a distance r from the emission point on the straight line connecting the detection means
A distance between a point on a straight line adjacent to a straight line formed by the emission point and the first detection means and a distance between the first detection means and 2σ (r)
The detection means is arranged so as to be within 3σ (r). Here, the range of σ (r) is given by the following equation.

[0011]

0.05r ^0.8 ≦ σ (r) ≦ 0.3r ^{0.92 The} above inequality is obtained by applying the Pasquill-Gifford diagram shown in FIG. This is an approximation of the relational number 0.98 or higher by a power-type equation.

In addition, the problem is that, of the straight lines connecting the emission point and the other detection means, the angle formed by the straight line adjacent to the first detection means and the straight line connecting the emission point and the first detection means is formed. θ, the angle θ is within 2 sin ^-1 {σ (r) / r},
Alternatively, the problem can be solved by arranging the detecting means so as to be within 2 sin ^-1 {3σ (r) / 2r}.

Further, of the points at a distance r from the emission point on a straight line connecting the emission point and the other detection means, a point on a straight line adjacent to the emission point and the straight line formed by the first detection means. ,
The distance between the first detecting means is within 4σ (r) or 6
The problem can also be solved by arranging the detecting means so as to be within σ (r). In addition, among the straight lines connecting the emission point and the other detection means, the angle θ is defined as an angle θ formed by a straight line connecting the emission point and the first detection means and a straight line adjacent to the first detection means. The same applies to the case where the detecting means is arranged so as to be within 2 sin ^-1 {2σ (r) / r} or within 2 sin ^-1 {3σ (r) / r}.

The detecting means arranged in the environment can be constructed by combining a fixed detecting means whose position is fixed in the environment and a movement detecting means movable in the environment. . When the movement detection means is combined, the weather prediction means and the diffusion prediction means, or the weather observation means and the diffusion prediction means predict the diffusion range of the substance released into the environment, and the diffusion range of the substance released to the movement detection means The movement position is indicated and displayed, and the movement detection means moves to an appropriate position to measure the concentration.

[0015]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows a first embodiment of the arrangement of the detecting means in the environment monitoring apparatus of the present invention. Around the emission point 5, fixed detection means 1 for measuring the concentration of a substance which may diffuse from the emission point into the environment and weather data such as wind direction and wind speed.
2, 3 are arranged. In this embodiment, the wind direction at that time is 6
Therefore, the movement detection means 4 is arranged on the lee of the release point in order to diffuse the substance released from the fixed detection means 1 and 2.

In this case, the point of the distance r from the emission point on the straight line connecting the emission point and the movement detection means 4 and the distance d between the fixed detection means 1 and 2 are defined by the diffusion width of It is within 2σ (r) or 3σ (r) from the standard deviation σ (r). By setting the distance d within 2σ (r), at least two detection means are arranged in a section of about 95% of the spread of the emitted substance, and the concentration of the emitted substance can be measured. If the distance d is within 3σ (r), at least two detection means are arranged in a section of about 99% of the spread of the emission material. The movement detecting means 4 can be applied to an automobile equipped with a device for detecting the concentration, the wind direction, the wind speed, and the like, a track vehicle running on a preset track, or the like.

Next, a second embodiment of the arrangement of the detecting means in the environment monitoring apparatus of the present invention is shown in FIG. Around the emission point 5, fixed detection means 1, 2, 3 for measuring the concentration of a substance which may diffuse from the emission point 5 into the environment and weather data such as wind direction and wind speed are arranged, and the movement detection means 4 is provided. Is located leeward of the discharge point 5. In this case, assuming that an angle between a straight line connecting the emission point 5 and the fixed detection means 1 or 2 and a straight line connecting the emission point and the movement detection means 4 is θ, the angle θ is 2 sin ⁻¹ {σ
(r) / r} or 2 sin ^-1 {3σ (r) / 2r}. The angle θ is 2 sin ⁻¹ {σ
By setting it within (r) / r｝, at least two detection means are arranged in a section of about 95% of the spread of the emitted substance. Further, the angle θ is set to 2 sin ⁻¹ {3σ (r) / 2r}.
Within this range, at least two detecting means are arranged in a section of about 99% of the spread of the emitted substance, and the emitted substance can be captured.

FIG. 9 shows a third embodiment of the arrangement of the detecting means in the environment monitoring apparatus of the present invention. Around the emission point 5, fixed detection means 1 for measuring the concentration of a substance which may diffuse from the emission point into the environment and weather data such as wind direction and wind speed.
2 and 3 are arranged, and the movement detecting means 4 is arranged leeward of the discharge point. In this case, the distance d between the fixed point detecting means 1 and the distance r from the point of emission on the straight line connecting the emission point and the movement detecting means 4 is within 4σ (r) or within 6σ (r). . By setting the distance d within 4σ (r), at least one detecting means is arranged within a section of about 95% of the spread of the emitted substance, and the concentration of the emitted substance can be measured. If the distance d is within 6σ (r), at least one detecting means is disposed in a section of about 99% of the spread of the emission material.

Next, FIG. 10 shows a fourth embodiment of the arrangement of the detecting means in the environment monitoring apparatus of the present invention. Around the emission point 5, fixed detection means 1, 2, 3 for measuring the concentration of a substance which may diffuse from the emission point 5 into the environment and weather data such as wind direction and wind speed are arranged, and the movement detection means 4 is provided. Is located leeward of the discharge point 5. In this case, assuming that the angle between the straight line connecting the emission point 5 and the fixed detection means 1 or 2 and the straight line connecting the emission point and the movement detection means 4 is θ, the angle θ is 2 sin ⁻¹ {2σ
(r) / r｝ or within 2 sin ⁻¹ {3σ (r) / r｝. The angle θ is 2 sin ⁻¹ {2
By setting it within σ (r) / r｝, at least one detecting means is arranged in a section of about 95% of the spread of the emitted substance. Further, the angle θ is set to 2 sin ⁻¹ {3σ (r) / r｝
Then, at least one detecting means is arranged in a section of about 99% of the spread of the emitted substance, and the emitted substance can be captured.

FIG. 1 is a block diagram of an environment monitoring apparatus according to the present invention.
It is shown in FIG. Stationary detection means 1, 2, 3 and movement detection means 4 are arranged in a facility such as a factory or a plant, that is, in the environment around the emission point. In this environment monitoring device, a meteorological data collection device collects, as weather data, weather observation values and numerical prediction data provided by the Japan Meteorological Agency and data from weather observation means in the facility. Based on the collected meteorological data, the meteorological analyzer obtains distributions around the facility related to weather, such as wind speed, wind direction (wind speed vector), temperature, humidity, and rainfall, and within a monitoring target range.

Weather data and weather analysis data are displayed and output as needed. If any abnormality occurs in the facility and there is a concern about release of a substance that may affect the environment, the diffusion analyzer normalizes the release concentration at the release point to a unit concentration and performs a diffusion analysis. Analytical data such as the diffusion state based on the result and the concentration distribution standardized by the emission point concentration are displayed by the control / management device and transmitted to the movement detecting means 4. The analysis data transmitted to the movement detecting means 4 is displayed in the movement detecting means 4, and a position suitable for measurement is specified. The movement detecting means 4 moves into the diffusion range of the emission substance based on the display and instruction, and measures data such as concentration.

The measurement results of the fixed detection means 1, 2, 3, and the movement detection means 4 are transmitted to the control and management device, and the emission point calculated by the diffusion analysis device based on the data measured in the environment. The density distribution standardized by the density is converted to an actual value. As a result, the concentration distribution in the environment can be evaluated, and the emission concentration at the emission point is determined. As a result, the state of diffusion and concentration distribution of substances released into the environment can be evaluated, and data for taking appropriate measures in an emergency can be provided.

As described above, the movement detecting means 4 can be applied to an automobile equipped with a device for detecting the concentration, the wind direction, the wind speed, and the like, or a track vehicle running on a predetermined track. In addition, these movement detection means can be used for manned vehicles,
It can be realized by an unmanned vehicle controlled by a management device or the like.
Further, transmission of information between the movement detection means 4 and the control / management device and control of the movement detection means 4 can be achieved by wire or wirelessly.

FIG. 12 is a display example when the control / management device displays the analysis result of the diffusion analysis device on the movement detecting means or the like. The main shapes of factories and plants serving as the emission points 5, the main terrain information 11 such as contour lines, the average wind direction, the wind speed 6, and the arrangement of the fixed detection means 3 are displayed on the screen. The spread 8 of the released / diffused substance is displayed based on the diffusion state and the concentration distribution in the analysis data, and the movement instruction position 9 to the movement detecting means 4 is shown at the center of the spread 8 of the released / diffused substance.

In the present embodiment, the spread of the emitted / diffused material 8
Since the fixed detector 3 does not exist within the range, the moving detector 4 captures the spread 8 of the emitted / diffused substance and measures the concentration in a manner that complements the space between the fixed detectors. In the calculation normalized by the emission concentration at the emission point in the diffusion analysis device, when the uniform wind direction and wind speed are assumed within the analysis range and the terrain is relatively flat, the analytical solution based on the following Gaussian plume model is used This can be easily implemented.

[0027]

(Equation 2)

Here, χ (x, y, z) is the spatial density, q is the amount of diffused substance released per unit time, u is the wind speed, σ _y , σ
_z is the standard deviation of the horizontal and vertical diffusion widths, H is the emission height, x is the wind horizontal coordinate, y is the horizontal coordinate orthogonal to x, and z is the vertical coordinate.

On the other hand, when the wind direction and the wind speed are not uniform within the analysis range and the influence of the terrain must be considered,
Diffusion analysis is possible by the pseudo particle tracking method of releasing and tracking a large number of pseudo particles schematically shown in FIG. The behavior of the quasi-particles by this method is tracked based on the following equation.

[0030]

X (t) = X (t) + ΔtU where X (t) is the position of the particle at time t, U is the moving speed of the pseudo particle, and Δt is the time step in the calculation. Further, U is the mean wind velocity Uw, vector quantity comprised of turbulent fluctuation amount U _D like wind speed in the particle position, determined in accordance with a result of the weather analysis. In this method, an amount corresponding to the emission rate of the emitted substance is given to each pseudo particle, and the number of particles in the volume constituted by the calculation grid is calculated and converted, thereby obtaining the concentration in the atmosphere. Assuming that the amount of diffused substance released per unit time is q and the number of pseudo particles released per time step is n, the spatial concentration χ (x, y, z) is given by the following equation.

[0031]

(Equation 4)

Here, N is the number of particles contained in the cell at the position (x, y, z), and Δx, Δy, and Δz are calculation cell widths in the density calculation.

[0033]

According to the environmental monitoring apparatus of the present invention, the distance between the fixed detection means and the movement detection means in the environment, the emission point, and the distance between the fixed detection means and the movement detection means in the environment are considered in consideration of the diffusion width of the substance released into the environment determined from the weather conditions. The angle between the straight lines formed by the means is set appropriately. Thus, under most weather conditions, at least one or two detection means can always detect the spread of the substance released into the environment and measure the concentration. For this reason, the concern that the substance released into the environment will slip through between the detecting means arranged in the environment and the detecting means is solved.

Further, in the environment monitoring device of the present invention, the diffusion range of the substance released into the environment is predicted by the weather prediction means and the diffusion prediction means, or the weather observation means and the diffusion prediction means, and released to the movement detection means. Indicate and display the diffusion range and movement position of the substance. Thereby, the movement detecting means moves to an appropriate position according to the diffusion state of the released substance, and the concentration can be measured.

[Brief description of the drawings]

FIG. 1 is a diagram showing an arrangement of detection means in an environment monitoring device according to a first embodiment of the present invention.

FIG. 2 is a diagram showing an arrangement of detection means in an environment monitoring device according to a second embodiment of the present invention.

FIG. 3 is a diagram showing an example of the arrangement of detection means in a conventional environment monitoring device.

FIG. 4 is a characteristic diagram showing a concentration distribution measurement result in an arrangement of detection means in a conventional environment monitoring device.

FIG. 5 is a Pasquill-Gifford diagram (horizontal diffusion width).

FIG. 6 is a conceptual diagram of spreading of a diffusion material.

FIG. 7 is a characteristic diagram showing a concentration distribution of a diffusion substance.

FIG. 8 is a characteristic diagram showing a relationship between a 95% section of the spread of the diffusion material and a comparison of the width of the azimuth.

FIG. 9 is a diagram showing an arrangement of detection means in the environment monitoring device according to the third embodiment of the present invention.

FIG. 10 is a diagram showing an arrangement of detection means in the environment monitoring device according to the fourth embodiment of the present invention.

FIG. 11 is a block diagram of environment monitoring by the environment monitoring device of the present invention.

FIG. 12 is a diagram showing an example of indication and display of a diffusion range and a movement position of a released substance in the environment monitoring device of the present invention.

FIG. 13 is a conceptual diagram of diffusion prediction using pseudo particles.

[Explanation of symbols]

1, 2, 3 ... fixed detection means, 4 ... movement detection means, 5 ... emission point, 6 ... wind direction, 7 ... 16 directions, 8 ... spread of emitted / diffused substances, 9 ... movement instruction position to movement detection means, 10: pseudo particle, 11: topographic information such as contour lines.

Claims (7)

[Claims] 1. An environment monitoring apparatus in which detection means for detecting the concentration of a substance released into the environment is disposed in the environment, wherein the distance from the release point to the first detection means is represented by r (m) and distance r. When the standard deviation of the diffusion width of the emission material is σ (r) (m), among the points at a distance r from the emission point on a straight line connecting the emission point and other detection means, the emission point and the second An environment monitoring device, wherein a distance between a point on a straight line adjacent to a straight line formed by the first detecting means and the first detecting means is within 2σ (r) or within 3σ (r). Where σ (r)
Is given by the following equation. 0.05r ^0.8 ≦ σ (r) ≦ 0.3r ^0.92 2. An environment monitoring apparatus in which detection means for detecting the concentration of a substance released into the environment is disposed in the environment, wherein the distance from the release point to the first detection means is represented by r (m) and distance r. When the standard deviation of the diffusion width of the emission material is σ (r) (m), among the straight lines connecting the emission point and other detection means,
A straight line adjacent to the first detection means, an emission point, and the first
When the angle formed by the straight line connecting the detecting means is θ, the angle θ
Is within 2 sin ^-1 {σ (r) / r｝, or 2 sin ^-1 {3σ
An environment monitoring device characterized by being within (r) / 2r｝. Here, the range of σ (r) is given by the following equation. 0.05r ^0.8 ≦ σ (r) ≦ 0.3r ^0.92 3. An environment monitoring apparatus in which a detecting means for detecting the concentration of a substance released into the environment is disposed in the environment, wherein a distance from the emission point to the first detecting means is represented by r (m) and a distance r. When the standard deviation of the diffusion width of the emission material is σ (r) (m), among the points at a distance r from the emission point on a straight line connecting the emission point and other detection means, the emission point and the second An environment monitoring device, wherein a distance between a point on a straight line adjacent to a straight line formed by the first detecting means and the first detecting means is within 4σ (r) or within 6σ (r). Where σ (r)
Is given by the following equation. 0.05r ^0.8 ≦ σ (r) ≦ 0.3r ^0.92 4. An environment monitoring apparatus in which detection means for detecting the concentration of a substance released into the environment is disposed in the environment, wherein the distance from the release point to the first detection means is represented by r (m) and distance r. When the standard deviation of the diffusion width of the emission material is σ (r) (m), among the straight lines connecting the emission point and other detection means,
A straight line adjacent to the first detection means, an emission point, and the first
When the angle θ is formed by a straight line connecting the detection means, the angle θ is within 2 sin ⁻¹ {2σ (r) / r｝ or 2 sin ⁻¹ {3σ
An environment monitoring device characterized by being within (r) / r｝.
Here, the range of σ (r) is given by the following equation. 0.05r ^0.8 ≦ σ (r) ≦ 0.3r ^0.92 5. An environment monitoring apparatus according to claim 1, wherein a position where said detection means is arranged is fixed in an environment. 6. The apparatus according to claim 1, wherein said detecting means comprises a fixed detecting means whose position is fixed in an environment, and a moving detecting means movable in the environment. An environmental monitoring device characterized in that: 7. The diffusion range of a substance released into the environment is predicted by weather forecasting means and diffusion prediction means or the weather observation means and diffusion prediction means, and the diffusion range and movement position of the substance released to the movement detection means. An environmental monitoring device characterized by indicating and displaying information.