JPH0612325B2 - Method for measuring the degree of inclusion of suspended matter in water and its measuring device - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for measuring the degree of inclusion of suspended solids in water and a measuring apparatus therefor.

<Prior art> As is well known, suspended sediment flows along with rainwater into reservoirs for hydroelectric power generation, drinking water, etc.

However, if the turbid water containing a large amount of suspended sediment in a hydroelectric power plant is taken as it is, the suspended sediment accumulates in waterways and sand basins and hinders the flow of water, and also significantly damages turbines and conduits. I will let you.

For this reason, at the present stage, at the hydroelectric power station, if the amount of sediment flowing into the river increases due to heavy rainfall, etc., the amount of water intake is controlled by referring to the flow rate of the river.

However, since it is not possible to accurately estimate the suspended sediment flowing into the reservoir from the flow rate of the river,
It was extremely inadequate as a measure to prevent damage to the water turbine due to the above-mentioned suspended sediment.

On the other hand, even in the storage value for drinking water, since the inflow of turbid water significantly pollutes the water in the reservoir, its rapid release is desired, but in this type of reservoir, the temperature difference between the surface layer and the deep layer, Since there is a difference in the concentration of suspended sediment and the distribution of turbid water cannot be accurately ascertained, it is the actual situation that it is difficult to take countermeasures for it as at the power plant.

It seems that such a problem can be easily solved, for example, by measuring the contamination degree of suspended solids in the reservoir and controlling the intake and discharge based on the measured value, but it has been used conventionally. The method for measuring the degree of inclusion of suspended solids and the measuring apparatus therefor, particularly when applied to the applications as described above,
There was a technical problem described below.

<Problems to be solved by the invention> That is, as a method for measuring the degree of suspended matter contamination that has been conventionally provided, the suspended sediment contained in the sample water collected from the site is separated with a filter paper or a centrifuge, and separated. We measured the suspended sediment and measured the degree of contamination by laboratory tests, and the method of projecting light rays on the sample water and measuring the intensity of transmitted or scattered light to determine the degree of contamination of suspended substances. There is.

However, in the former method of measuring the degree of inclusion of suspended matter,
Although the amount of suspended sediment can be measured accurately, it cannot be measured in real time at the current position, so it cannot be used for water intake or water discharge control of the reservoir described above.

On the other hand, with the latter method of measuring the degree of inclusion of suspended solids, it is possible to measure in real time at the current position, but if it is left installed in water, there will be sedimentation and adhesion of sediment, etc.
In continuous measurement for a long time, it is necessary to remove these, maintenance and management of the measuring equipment is troublesome, and the measurement error is large due to the color of the suspended sediment, and the measurement range is narrow and a large amount of suspended sediment is included. It was not suitable for measuring the degree of contamination of suspended water in suspended matter.

The present invention has been made in view of such conventional problems, and an object of the present invention is to perform continuous measurement in real time at a current position and measurement over a wide range under easy maintenance and management. It is intended to provide a method for measuring the degree of contamination of suspended solids in water and a measuring device therefor.

<< Means for Solving the Problem >> In order to achieve the above object, the method for measuring the degree of inclusion of suspended solids in water according to the present invention measures the depth, water pressure, and water temperature of a measurement target position, and measures each of these measured values. It is characterized in that the density increase amount due to the mixing of the suspended matter is obtained from the standard water density and the standard water density, and the mixing degree of the floating substance is determined by the magnitude of the density increase amount.

Further, the apparatus for measuring the degree of inclusion of suspended solids in water according to the present invention, a water pressure gauge installed at a known depth, a thermometer for measuring water temperature, a standard value in the measurement value of the water pressure gauge and the measurement value of the thermometer. It has a calculating device which calculates the density increase amount by mixing of a suspended substance from water density.

<< Advantageous Effects of the Invention >> According to the method and apparatus for measuring the degree of contamination of suspended solids in water, a water pressure gauge and a thermometer are installed in water, and the suspended matter is mixed from the measured values and standard water density. Since the density increase amount is calculated to obtain the degree of inclusion of suspended solids in water, real-time continuous measurement at the current position is possible.

In addition, since the water pressure gauge generally has a liquid-tight structure,
It is not affected by the accumulation and adhesion of suspended sediment, and maintenance and management are almost unnecessary.

Further, since some water pressure gauges have various measuring lenses, it is possible to measure a wide range of the degree of inclusion of suspended solids by appropriately selecting them according to the amount of suspended solids contained in the water to be measured. it can.

<Example> Hereinafter, a preferred example of the present invention will be described in detail with reference to the accompanying drawings.

First, the principle of the measuring method of the present invention will be described before describing specific examples of the present invention.

FIG. 1 is a diagram for explaining the principle of the measuring method of the present invention. In FIG. 1, when the water pressure at the water depth h point is P, the unit weight of running water at the same point: γ _W is expressed by the following equation.

γ _W = P / h ... On the other hand, the density ρ _W of the flowing water is given by the following equation, where gravitational acceleration is g.

ρ _W = γ _W / g ... Now, let Δρ be the increase due to mixing of suspended solids with respect to the density ρ _{W of} running water, and let the density of fresh water at the same temperature as running water be ρ ′ _W , then Δρ = ρ _W −ρ ′ _W ……, and if the water depth h, water pressure P, and water temperature are known, the increment Δρ of the flowing water density due to the inclusion of suspended matter can be obtained from these values.
Can be calculated, and the degree of inclusion of the floating substances in the running water can be quantitatively measured by the size of the increment Δρ.

On the other hand, when the particle density of suspended solids is ρ _S , the suspended solid mass m in a unit volume of running water is expressed by the following formula.

_{m = ρ S × V S =} ρ S × (ρ W -ρ 'W) × V / (ρ S -ρ' W) = ρ S × Δρ / (ρ S -ρ 'W) ...... V S: Unit Volume occupied by suspended solids in flowing water of volume V: Unit volume Here, since suspended solid particle density ρ _S is considered to be almost constant at the same measurement point, suspended solid mass m in running water unit volume is Increase in running water density due to mixing Δρ
There is a strong first-order positive correlation with, and the above equation can be approximated as follows.

Therefore, for example, (1) Δρ obtained by the measurement of the present invention is compared with the suspended matter mass spectrometry result obtained by local water sampling, and k is set in advance.

Alternatively, (2) the suspended matter particle density ρ _S is actually measured and k is set in advance.

The mass m of suspended matter contained in the unit volume of the flowing water can be obtained from the increasing degree of flowing water Δρ based on the equation.

More specifically, in the case of the method (1), it is necessary to measure the mass m of suspended solids contained in a unit volume of flowing water and the increase Δρ of flowing water density at the actual intake point. From this, the constant k at the intake point is known from the relationship of the equation, and the mass of suspended matter m can be obtained by measuring Δρ of the flowing water thereafter. According to the method of (2),
, Clearly from the comparison of the equations, k = ρ _S / (ρ _S −ρ ′ _W ). Therefore, if the particle density ρ _S of the suspended matter at the actual intake point is measured, It is possible to obtain the suspended matter mass m at that point by measuring. This measurement method is based on the finding that ρ _S at the same measurement point can be regarded as substantially constant, as described above. That is, at a specific point on a river where an intake point is provided, first the constant k unique to that point is set.
Then, the mass of suspended solids at that point can be calculated continuously after that. When measuring at different water intake points, the constant k at that point may be measured again.

FIG. 2 to FIG. 4 show an embodiment of the apparatus for measuring the degree of inclusion of suspended solids in water according to the present invention.

The floating substance mixing degree measuring device shown in the figure is composed of two water pressure gauges 12, 1 installed at depths h1 and h2 of a water storage value 10.
4 and the water temperature at the installation position of the water pressure gauges 12 and 14 2
It is composed of two thermometers 16 and 18, and an arithmetic unit 20 to which the outputs of these meters are input.

FIG. 3 shows an example of the water pressure gauges 12 and 14.

The water pressure gauges 12 and 14 shown in the figure are so-called crystal type water pressure gauges. A filter is attached to the lower end of the case 22, and a crystal sensor 26 is built into the case 22 substantially at the center. There is.

A displacement transmitting member 28 having a fulcrum at the center is fixedly attached to one end of the crystal sensor 26, and the displacement transmitting member 28 is fixed.
A pair of bellows 32 and 34, one end of which is fixed to the frame body 30, are arranged on the other end side with the fulcrum of the two being sandwiched therebetween.

The bellows 32 on the upper side is exposed to the atmosphere via an atmosphere releasing tube 36, and the bellows 34 on the lower side is connected to the filter 24 via a water pressure transmitting tube 38.

In the water pressure gauges 12 and 14 configured as described above, the change in water pressure due to the change in water depth is transmitted to the bellows 34 on the lower side via the water pressure transmission tube 38, and at this time, the lower end of the bellows 34 is attached to the frame body. Since it is fixed to 30, only its upper end expands and contracts in response to water pressure, and this expansion and contraction causes the displacement transmitting member 28 to move.
Is applied to the crystal sensor 26 via the, and the crystal sensor 26 is distorted.

When the crystal sensor 26 is distorted, its oscillation frequency changes, and the frequency change is converted into water pressure.

At this time, since the bellows 32 on the upper side is released to the atmosphere through the tube 36, the fluctuation of the atmospheric pressure due to the high pressure or the low pressure is detected, and the influence on the water pressure due to the change of the atmospheric pressure applied to the water surface is detected. to erase.

On the other hand, the arithmetic unit 20 has a converter 20a for converting the input signals from the water pressure gauges 12, 14 and the thermometers 16, 18 into a digital signal, and an arithmetic operation for receiving a signal from the converter 20a and processing the signal. And a container 20b.

FIG. 4 shows an outline of the processing procedure executed by the arithmetic unit 20b. In the processing procedure, first, in step S1, the known installation depths h1 and h2 of the water pressure gauges 12 and 14 and their output signals P1 and P2 are set. And the output signals T1, T2 of the thermometers 16, 18 are taken in via the converter 20a.

Next, in step S2, the distance between the installation positions of the water pressure gauges 12 and 14 and the water pressure difference ΔP = P2-P1 are calculated, and in step S3, the unit of running water is calculated from these calculated values based on the above-mentioned formula. The volume weight γ _W is calculated.

In step S4, the density ρ ′ _W of fresh water at T2 ° C. is calculated, and the density ρ _{W of} running water is calculated by dividing γ _W by the gravitational acceleration g.

In this case, since the density change with respect to the temperature of fresh water is well known, this may be stored in advance.

In a succeeding step S5, the density increase Δρ due to the inclusion of the suspended matter is calculated based on the above-mentioned equation, and the processing procedure is ended.

Here, as described above, for example, if the suspended matter analysis is performed by local water sampling and the constant k in the above equation is set in advance, the suspended matter amount m can be obtained based on the result of step S5. Of course it is possible.

By the way, the floating substance contamination degree measuring device of the present invention configured as described above enables continuous measurement in real time at the current position.

In addition, according to the experiments by the present inventors, the amount of suspended matter is 200 pp.
It has been confirmed that automatic measurement is possible from low concentrations around m to high concentrations of tens of thousands of ppm.

Further, since the water pressure gauges 12 and 14 have the crystal sensor 26 built in the cover 22, they are not affected by the adhesion of water stains or floating substances, and therefore maintenance and inspection is almost unnecessary.
Very easy to manage.

FIG. 5 shows another embodiment of the present invention. FIG. 5 (A) shows a large number of water pressure gauges 1 arranged at equal intervals from the water surface.
This is an example of arranging 2a, 12b, ..., 12n, and by arranging a large number of water pressure gauges in this way, the distribution state of suspended solids can be accurately grasped at each depth continuously from the surface layer such as a reservoir to the deep layer.

Further, FIG. 2B shows a structure in which a pair of water pressure gauges 12a 'and 12b' are fixed at a predetermined interval and moved vertically.

With this configuration as well, the amount of suspended solids at any water depth can be measured in the same manner as above.

Further, FIG. 6C shows the water pressure gauges 12a ′ and 12b ′ of FIG. At the position, it becomes possible to measure the contamination degree of suspended matter at any depth.

[Brief description of drawings]

FIG. 1 is a diagram for explaining the principle of the measuring method of the present invention, and FIGS. 2 to 4 show an embodiment of a device for measuring the degree of inclusion of suspended solids in water according to the present invention, and FIG. FIG. 3 is a detailed view of the water pressure gauge, FIG. 4 is a flowchart of the arithmetic unit, and FIG. 5 is an explanatory view showing another embodiment of the measuring apparatus. 12, 14 ... Water pressure gauge 16, 18 ... Thermometer 20 ... Computing device

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Yuichi Komatsuzaki Yuichi Komatsuzaki 294-21 Otsu, Komoro-shi, Nagano Tokyo Electric Power Co., Inc. Chikumagawa Electric Power Station (72) Inventor Shoichi Shinoda 5-4 Kojimachi, Chiyoda-ku, Tokyo Nippon Koei Co., Ltd. (72) Inventor Toshio Kato 5-4 Kojimachi, Chiyoda-ku, Tokyo Japan Kogyo Co., Ltd. (72) Inventor Kunio Niisato 1-5-13 Shinkawa, Chuo-ku, Tokyo Nakashou Sokki Co., Ltd. (72) Inventor Toshiya Ishii, 1-5-13 Shinkawa, Chuo-ku, Tokyo Nakasaseki Co., Ltd. (56) Reference JP-A-57-37245 (JP, A)

Claims (2)

[Claims] 1. A method for measuring the degree of mixing of suspended matter mixed in water, which comprises measuring the depth, water pressure, and water temperature of a measurement target position, and floating the measured value and standard water density. A method for measuring the degree of contamination of suspended solids in water, which comprises determining the amount of increase in density due to contamination of a substance and determining the degree of contamination of suspended matter according to the magnitude of this increase in density. 2. A water pressure gauge installed at a known depth, a thermometer for measuring the water temperature, and a density increase due to the inclusion of suspended matter from the water pressure gauge measurement value and the standard water density in the thermometer measurement value. A device for calculating the amount of suspended solids in water, comprising: a calculation device for calculating the amount.