JP2008128888A - Water quality meter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a water quality meter which is adaptable to many applications. <P>SOLUTION: The water quality meter includes a data operator for converting the light intensity and the pulse counted value of the light interference fringe based on the transmitted light, scattered light and the light where the transmitted light and the scattered light are mixed, obtained by irradiating the particles in a measuring tank with the light beam from a light source into an electrical signal by a photodetector and calculating the particle size or the turbidity from the electrical signal and is also equipped with a particle size distribution forming device for calculating the particle size distribution, that shows the particle size, with respect to mass or individual ratio for each of many kinds of standard calibration liquids; and a calibration liquid determining device, capable of determining calibration liquid in the measuring tank, on the basis of the particle size distribution calculated by the particle size distribution forming device. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a water quality meter used in water purification plants, water treatment plant facilities, and the like.

Conventional turbidity detectors use light or laser light to measure transmitted light that is not absorbed by the component (transmission type), to measure the scattered light reflected from the component (scattering type), or to mix There are types that measure transmitted light and scattered light (mixed type), and types that measure two types of scattered light at different angles (improved type). In addition, there are scattering types such as those that receive light scattered by introducing light into water and reflected from components, and surface scattering light types that introduce light from above the water surface instead of underwater. Furthermore, the technique described in Patent Document 1 describes a technique for obtaining turbidity only by calculation.
Japanese Patent Laid-Open No. 10-311784 49th National Waterworks Research Conference Heisei 10.5 (8-16) Correlation between turbidity and fine particle count of filtered water

  In April 2004, the Ministry of Health, Labor and Welfare enforced the “Ministerial Ordinance for Revision of Part of the Water Supply Law Enforcement Rules”. According to this ministerial ordinance, the standard calibration solution for water quality meters that measure water distribution outside the water purification plant is determined to be a PSL standard solution [a mixture of several single-particle size PSL (polystyrene latex) at a specified ratio]. It was.

However, the standard calibration solution used in the past is “kaolin” or “formazin”, which causes great confusion and confusion for manufacturers and users. The first confusion is that even if the measured value of the sample solution A is 1.0 degree when calibrated with the conventional calibration solution Kaolin, the measured value of the sample solution A is calibrated with the PSL standard solution. Is not 1.0 degree ". This difference in value is about 1.2 times in measurement method A, and about 1.5 times in measurement method B. The second cause of confusion is that the Ministerial Ordinance states that PSL must be used for water quality meters outside the water treatment plant. It is said that there is no problem. From these facts, it became an important matter which calibration solution was used for calibration.

  In the above-mentioned Patent Document 1, there is no description about calibration by changing the standard calibration solution, and it is difficult to put it to practical use.

  As another water quality meter's needs, the Ministry of Health, Labor and Welfare's provisional countermeasure guidelines for Cryptosporidium (Cryptospodium is not directly measured, so turbidity is used as an alternative indicator). .It is specified that the temperature is maintained at 1 degree or less. Generally, the particle diameter of Cryptosporidium is about 5 μm, and there is a demand for a water quality meter having high sensitivity for particles of about 5 μm. Water quality meters include scattering, laser, and integrating sphere methods. FIG. 2 in Non-Patent Document 1 described above shows the particle size sensitivity by each method. From this figure, it can be seen that the sensitivity for each particle size varies depending on various measurement methods. This difference in sensitivity results in no correlation between the measurement methods. The problem to be solved is to display the measurement values of each measurement method with one instrument.

  Therefore, there are problems 1, 2, and 3 described below in putting the water quality meter described above into practical use.

  (Problem 1) A water quality meter capable of correcting a measured value so that it becomes a measured value of a meter calibrated with another standard calibration solution.

  (Problem 2) A water quality meter in which measurement values of other methods can be understood by one measuring device.

  (Problem 3) A water quality meter having no sensitivity on the side of a fine particle (eg, 1 μm or less) or on the side of a large particle.

  An object of the present invention is to provide a water quality meter that can solve the above-described problems and can be applied to various uses as a result.

In order to achieve the above object, the invention corresponding to claim 1 is directed to transmitting light, scattered light, and light mixed with transmitted light and scattered light obtained by irradiating a particle in a measuring tank with a light beam from a light source. In the water quality meter equipped with a data calculator that converts the light intensity of the light interference fringes based on either, or the pulse count value into an electrical signal by the light receiving element, and calculates the particle size or turbidity from this electrical signal,
A particle size distribution generator for obtaining a particle size distribution indicating a particle size with respect to a mass ratio or a number ratio for each of various types of standard calibration solutions;
An input device that can specify one of many kinds of standard calibration solutions is added, and one of the standard calibration solutions is designated from the outside with the input device, and calibration is performed with the known standard calibration solution. Correction means for correcting
It is the water quality meter characterized by comprising.

  ADVANTAGE OF THE INVENTION According to this invention, the water quality meter applicable to many uses can be provided, and the following effects are also acquired.

  1) A single measuring instrument can be used as a water quality meter that understands the measured values of a plurality of different methods described above.

  2) It is possible to confirm with one instrument which calibration solution will change the current measured value.

  3) Regardless of which standard calibration solution is used, it is possible to realize a water quality meter that can correct the measurement value so that it becomes the measurement value of the meter calibrated with the designated standard calibration solution.

  Hereinafter, the water quality meter of the present invention will be described with reference to embodiments shown in the drawings, but before that, the outline of the present invention will be described.

  The above "Problem 3" cannot be solved by a conventional turbidimeter alone, but can be realized by obtaining and devising information on the particle state using an instrument capable of measuring the particle size state. The state of the particles includes the concentration, the number of particles, the particle weight, and the total number of particles in the distribution for each particle diameter. As a measuring instrument for measuring this, there is mainly a laser system. The object can be solved and the object can be achieved by obtaining such information of the sample water being measured and further constructing an apparatus capable of measuring in advance the degree of influence on each particle size distribution.

  In order to solve the above “Problems 1 and 2”, it is first necessary to investigate the cause of the indication value by various measurement methods “why it is different or why the measurement value is different depending on the calibration solution”. In order to solve this problem, unless a sample consisting of a single particle is actually measured to determine the degree of influence of each particle size distribution and the degree of influence of turbidity is not grasped, the correlation between various measuring instruments and various standard calibration solutions The correlation between the calibrated instruments is not known. Therefore, it is possible to grasp the turbidity influence of each single-distributed particle for each measurement method in advance, grasp the particle diameter state of various standard calibration solutions, and grasp the particle diameter state of the sample water currently being measured. Building a device can solve the problem and achieve the goal.

(Embodiment 1)
FIG. 1 is a block diagram for explaining the first embodiment. The light source 1 includes a lamp and a laser light source, and irradiates a light beam toward the measurement tank 3. The lenses 2 collect the light beam emitted from the light source 1 and irradiate the measurement tank 3. The lenses 4 provide the light receiving element 5 with any of the transmitted light, scattered light, and mixed light of the transmitted light and scattered light from the measurement tank 3 as parallel light. The measurement tank 3 is a part through which sample water to be measured passes. The light receiving element 5 converts an optical signal (optical information) into an electric signal.

  A data calculator (data converter) 6 mainly calculates an electrical signal from the light receiving element 5 and calculates a measured value of turbidity and particle diameter. Are connected to each other, and a calibration curve is created after fetching a set value recorded in advance in the recorder 8 and stored in the particle size distribution information storage 9 so as to be readable. The particle size distribution information is read, and the electrical signal of the light receiving element 5 is calculated as turbidity or particle size. For the calculation of the data calculator 6, a calibration curve is created after taking the set values held in the recorder, and when the particle size information is necessary for the turbidity calculation, the particle size distribution information is obtained, and the information Calculate the turbidity value based on the calculation.

  An output device 10, an input device 11, and a controller 12 described later are connected to the calibration liquid discriminator 7. The input device 11 can input a set value necessary for measurement and can designate one of many kinds of calibration solutions.

  The output unit 10 includes a recording unit and a display unit. The recording unit holds a set value input by the input unit 11 or a value set at the time of calibration. The display unit is calculated by the data calculator 6. Display of values, output of electrical signals equivalent to the values determined by the calibration liquid discriminator 7, numerical display when setting values are input, alarm information display, error information display, unit display, maintenance in progress The display of the inside, contact output, etc. are carried out. When the calibration liquid discriminator 7 designates one of the calibration liquids by the input unit 11, the measured value of the instrument (the value measured by the instrument with a certain calibration liquid) is automatically calculated as if calibration was performed with the designated calibration liquid. It has a function to correct. The controller 12 outputs a signal and controls them when operations such as adjusting the distance between the lenses 2 and 4 and changing the direction of the measuring tank 3 are necessary.

  The information in the particle size distribution information storage 9 may be stored in advance, or may be measured by the particle size distribution meter 13 and stored in the particle size distribution information storage 9.

  The operational effects of the embodiment of FIG. 1 described above will be described. In the embodiment of FIG. 1, it is important that the particle size distribution information storage 9 stores the particle size distribution information in advance, or the particle size distribution meter 13 measures the particle size distribution information. Therefore, the water quality meter itself can be corrected using this particle size distribution information. That is, as described above, when measuring turbidity, it is considered that the particle size distribution of the calibration solution and the actual sample has an effect. First, the water quality meter itself can recognize which calibration solution was used.

  In addition, the function which correct | amends to the value corresponding to the calibration liquid X designated by the input device 11, which is one of the functions of the calibration liquid discriminator 7 in the first embodiment, can be added to the data calculator 6; In addition, you may comprise somewhere in a water quality meter.

(Embodiment 2)
FIG. 2 shows the particle size distribution state of the calibration solution. For example, main types of calibration solutions available in Japan, that is, Kaolin manufactured by Company A, Kaolin manufactured by Company B, Kaolin manufactured by Company C, formazin, PSL. The particle distribution state which shows the particle size with respect to mass ratio or number ratio of this is shown.

  As a method for determining which kind of calibration liquid is used, as Example 1, it is determined by one distribution such as 0.5 to 1 μm and the overall ratio. As Example 2, the overall ratio is compared and determined for a plurality of distributions such as 0.5 to 1 μm and 1 to 3 μm. As Example 3, it is determined by the mutual ratio of a plurality of distributions such as 0.5 to 1 μm and 1 to 3 μm.

  The calibration solution is determined by these methods, and the information is displayed on the recording unit included in the output device connected to the calibration solution discriminator 7 or the display unit connected to the calibration solution discriminator 7. Good.

(Embodiment 3)
The measured value of turbidity is expressed in units of “degree”, “mg / L”, and the like. However, the same turbidity can be obtained by measuring the same concentration of “Kaolin manufactured by Company A” and “Kaolin manufactured by Company C” of the same concentration in “Particle distribution state of calibration solution in FIG. Don't be. This is because the degree of influence (depending on the size of the particles) at each particle size is different. Here, it is assumed that how much influence is exerted on the turbidity by the particles for each particle size distribution. Specifically, a sample having the same concentration of each particle size is prepared, and the degree of influence on turbidity is measured in advance. Based on this information, FIG. 3 shows an example of the influence degree of a certain water quality meter at each particle size (0.5 to 1 μm, 1 to 3 μm, 3 to 7 μm, 7 μm or more) in FIG. Information on the degree of influence graph of each particle size is also recorded in the recording unit of the output device 10. With these pieces of information, the above-described effects can be realized. For example, it is assumed that calibration is performed using Kaolin manufactured by Company A. At one time, the lot of kaolin manufactured by Company A changes and its mass ratio is usually (0.5-1 μm) :( 1-3 μm) = about 65:18
What was
(5-1 μm): (1-3 μm) = about 75: 8
Suppose that In this case, if there is a function shown in the second embodiment, an abnormality display / alarm can be output.

(Embodiment 4)
In FIG. 1, a function capable of displaying the measurement values of various types of measurement methods other than the measurement method of the water quality meter itself is added. There are measuring methods such as a laser method, a scattered light method, a transmitted light method, and an integrating sphere method. The difference in measured value appears in each case because the degree of influence on turbidity varies depending on the size of each particle size. Therefore, an instrument for measuring the state of particle size distribution and the turbidity influence of each particle distribution for each measurement method as shown in FIGS. 3 and 4 are measured in advance, and the data is recorded in the recording unit of the output device 10. If it does, the display of the water quality meter of a different measurement system can be shown. For example, the state of turbidity and particle diameter can be measured by a laser method, and a corrected integrating sphere measurement value can be displayed based on the turbidity value. (In this case, it is necessary to measure the turbidity influence of each particle distribution of laser type and integrating sphere type.)
There may be various details of the method, but for example, the mass can be calculated from the number of particles based on the particle size distribution of the current sample, and the mass can be multiplied by the coefficient of influence and the coefficient obtained in the test.

Example of calculation formula when particle size distribution is four k1 * m1 * e1 + k2 * m2 * e2 + k3 * m3 * e3 + k4 * m4 * e4 Formula 1
here,
k1, k2, k3, k4: Arbitrary correction factors m1, m2, m3, m4: Mass (or number) of each particle size distribution
e1, e2, e3, e4: the degree of influence of each particle size distribution (= actual value), or a theoretically determined constant.

(Embodiment 5)
The display unit of the output device 10 in FIG. 1 has a function of displaying a measured value of turbidity by cutting a part of a certain particle size distribution, cutting a small particle size side or cutting a large particle size side. It is.

The block diagram for demonstrating Embodiment 1 of the water quality meter of this invention. The figure which shows the particle size distribution of the calibration liquid which shows the particle size with respect to the mass ratio currently recorded on the recorder of FIG. The figure for demonstrating the influence degree of each particle diameter which has on the water quality meter of FIG. 1, specifically, a turbidimeter. The figure for demonstrating the influence degree of each particle diameter which has on the water quality meter of FIG. 1, specifically, a turbidimeter.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Light source, 2 ... Lenses, 3 ... Measuring tank, 4 ... Lenses, 5 ... Light receiving element, 6 ... Data calculator, 7 ... Calibration liquid discriminator, 8 ... Recorder, 9 ... Particle diameter distribution information storage DESCRIPTION OF SYMBOLS 10 ... Output device, 11 ... Input device, 12 ... Controller.

Claims (3)

Light intensity of light interference fringes or pulse count value based on any of transmitted light, scattered light, light mixed with transmitted light and scattered light obtained by irradiating a particle in the measurement tank with a light beam from a light source In a water quality meter equipped with a data calculator that converts the particle size or turbidity from this electrical signal by converting the signal into an electrical signal by a light receiving element,
A particle size distribution generator for obtaining a particle size distribution indicating a particle size with respect to a mass ratio or a number ratio for each of various types of standard calibration solutions;
An input device that can specify one of many kinds of standard calibration solutions is added, and one of the standard calibration solutions is designated from the outside with the input device, and calibration is performed with the known standard calibration solution. Correction means for correcting
The water quality meter characterized by comprising.   The water quality meter according to claim 1, further comprising a function for displaying measured values of various types of measurement methods other than the measurement method of the water quality meter itself.   2. The water quality meter according to claim 1, further comprising a function of displaying a measured value of turbidity by cutting a small particle diameter side or a large particle diameter side by a part of a certain particle size distribution. .

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