JP3265361B2 - Apparatus and method for measuring particles in liquid - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a measuring device and a measuring method for counting particles by distinguishing between particles and bubbles in a liquid.

[0002]

2. Description of the Related Art For example, when counting the number of particles mixed in highly purified water, particles may be miscounted due to bubbles in the liquid and the number of particles in the liquid may not be accurately counted. In order to solve the interference of counting the number of particles caused by the generation of bubbles in the liquid, conventionally, there has been a method of measuring a phase shift amount of light transmitted through the bubbles.

[0003]

However, in such a conventional method, it is not only technically difficult to accurately measure the phase shift amount of the light transmitted through the bubbles, but also the usable range is not limited. Had restrictions.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned conventional problems, and to in-line (can be used by being incorporated into a pipe or the like) a liquid containing particles or bubbles having various particle diameters. In addition, the present invention provides an apparatus and a method for non-invasively discriminating particles and air bubbles without causing a change in the number of particles or air bubbles.

[0005]

According to the present invention, in order to solve the above-mentioned problems, a liquid containing fine particles and bubbles is passed through a flow cell, and the particles or bubbles are detected by a light scattering method.
The method is characterized in that particles and bubbles are distinguished by irradiating the detected particles or bubbles with laser light and measuring the resulting fluorescence.

[0006] More specifically, the present invention includes a flow cell for flowing a fluid to be measured, and the particle-bubble detecting device which is disposed on the side upstream of the flow cell, distribution to the side downstream of the flow cell An apparatus for measuring particles in liquid, comprising: a laser light irradiation and spectrum analyzer provided, wherein the particle / bubble detector includes at least one of particles and bubbles in the liquid flowing in the flow cell. Detect that
In the laser beam irradiation and spectrum analysis device, the particle / bubble detection device may detect particles and
And that at least one of air bubbles is contained
In this case, the liquid flowing through the flow cell is irradiated with the particles and the bubble laser light, and the spectrum of the generated fluorescence is analyzed to determine the characteristics of the substance constituting the particles.
Between the spectrum of light and the spectrum of the scattered light of a bubble
The present invention provides a submerged particle measuring apparatus characterized in that particles and bubbles are distinguished by counting the number of particles.

Furthermore, the present invention is flushed with a liquid to be measured to the flow cell, in <br/> particle-bubble detection device disposed upstream side of the flow cell, the particles and bubbles contained in the liquid If at least one is detected ,
On the downstream side of the cell, the particles and bubbles contained in the liquid are irradiated with laser light to generate fluorescence or scattered light,
By analyzing the spectrum of the fluorescence or the scattered light, the spectrum specific to the substance constituting the particles and the gas are analyzed.
The difference between the mere fluorescence of the bubble and the spectrum of the scattered light
Distinguishes child and bubbles, to count the number of submerged particles characterized by counting the number of particles with distinguishing particles and bubbles
To provide a method for measuring particles in liquid.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the apparatus and method for measuring particles in liquid according to the present invention will be described below based on embodiments with reference to the drawings. FIG. 1 is a diagram illustrating a particle measuring device in liquid according to the present invention.

In FIG. 1, a flow cell 2 in which a liquid containing particles or bubbles to be measured is disposed in the middle of a pipe 1 is shown.
Flow inside. A particle / bubble detection device 3 is provided on the upstream side of the flow cell 2. The detection device 3 irradiates the liquid flowing in the flow cell 2 with detection light, and detects particles and bubbles in the liquid by a light scattering method.

A laser beam irradiation and spectrum analyzer 4 is provided on the downstream side of the flow cell 2. The laser light irradiation and spectrum analysis device 4 includes a laser irradiation device 5, a laser light receiving device 6, a spectrum analysis device 7, and a counting device 8. The laser light irradiation and spectrum analysis device 4 irradiates laser light to the bubbles or particles in the flow cell 2 from outside to generate fluorescence or scattered light, analyzes the spectrum of the fluorescence or scattered light, and analyzes the particles or bubbles. Is determined, and in the case of particles, a particle counting output is generated, and the number of particles is counted by a counting device.

When the particles / bubbles are detected by the particle / bubble detecting device 3, the detection output is transmitted to the laser beam irradiation and spectrum analysis device 4, and the laser beam irradiation is performed.

A method for measuring the number of particles in a liquid by the liquid particle measuring device having the above configuration will be described below with reference to FIG. A liquid containing particles or air bubbles to be measured is passed through the flow cell 2 (see FIG. 2A). Then, the particle / bubble detecting device 3 irradiates the liquid with detection light and detects the presence of particles or / and bubbles in the liquid by a light scattering method (see FIG. 2B).

When it is detected that particles or / and bubbles are contained in the liquid, a laser beam irradiation and spectrum analyzer 4 (see FIG. 2 (c). (The device 6 is omitted.) In this case, laser light is externally applied to bubbles or particles in the flow cell 2. Then, in the case of particles, fluorescence specific to the substance constituting the particles is generated.

In the case of bubbles, only scattered light due to the emitted laser light is generated. The fluorescence and scattered light generated by irradiating the laser light in this way are measured by a spectrum detection device. Then, the measured data is subjected to a spectrum analysis by a laser beam irradiation and spectrum analyzer 4 (FIG. 2).
(D), (e)).

The fluorescence spectrum has a spectrum peculiar to the substance constituting the particle, and is different from a spectrum of mere light scattered by bubbles. Based on the difference between the two spectra, it is determined whether the particle is a particle or a bubble. If the particle is determined, a particle counting output is generated, and the number of particles is counted by this counting device.

Although the embodiments and examples of the present invention have been described above, the present invention is not particularly limited to the above-described embodiments and examples, but falls within the technical scope described in the claims. It goes without saying that there are various other modes.

[0017]

According to the present invention having the above configuration, it is possible to clearly distinguish bubbles and particles in the liquid flowing in the flow cell. This enables accurate counting of particles in the liquid.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating an apparatus for measuring particles in liquid according to the present invention.

FIG. 2 is a diagram illustrating a method for measuring particles in liquid according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Piping 2 Flow cell 3 Particle / bubble detector 4 Laser beam irradiation and spectrum analyzer 5 Laser irradiator 6 Laser receiver 7 Spectrum analyzer 8 Counter

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Claims (2)

(57) [Claims] 1. A flow cell for flowing a liquid to be measured, a particle / bubble detection device disposed on a side upstream of the flow cell, and a laser beam irradiation and spectrum disposed on a side downstream of the flow cell. An in-liquid particle measurement device comprising an analyzer, wherein the particle / bubble detection device detects that at least one of particles and bubbles is contained in the liquid flowing in the flow cell, The laser light irradiation and spectrum analyzer, when the particle / bubble detector detects that at least one of particles and bubbles is contained in the liquid, the particles and bubbles in the liquid flowing through the flow cell. By irradiating the bubble laser light and analyzing the spectrum of the generated fluorescence, the spectrum specific to the substance constituting the particles and the gas are analyzed.
An apparatus for measuring particles in liquid, characterized in that particles are distinguished from bubbles by a difference from a spectrum of mere scattered light of bubbles and the number of particles is counted. 2. A method according to claim 1, wherein a liquid to be measured is flowed into the flow cell, and at least one of particles and bubbles contained in the liquid is detected by a particle / bubble detection device disposed upstream of the flow cell. On the downstream side of the flow cell, the particles and bubbles contained in the liquid are irradiated with laser light to generate fluorescence or scattered light, and the spectrum of the fluorescence or scattered light is analyzed, whereby the particles are formed.
Spectrum specific to constituent substances and simple fluorescence of bubbles
Or distinguish particles and bubbles by the difference with the spectrum of scattered light
And a feature to count the number of submerged particles characterized by counting the number of particles with distinguishing particles and bubbles
Liquid in the particle counting method, which.