JPH10221229A - Diluting tank and diluting device using it - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simplify a structure, miniaturize it, and attain high repetitive reproducibility by measuring and diluting a sample and a diluent with one diluting tank. SOLUTION: A sample is fed to a dilution chamber 11 while a solenoid valve SV3 is closed and a solenoid valve SV4 is opened. When the height of the liquid level reaches the protruded height (h) of a sample discharge pipe 12, the fed sample starts to be discharged to the outside from a sample discharge port 12a through the sample discharge pipe 12, then the feed of the sample is stopped, and the solenoid valve SV4 is closed. The volume of the sample is set to Vh . A diluent is fed into the dilution chamber 11, and a color former is also fed as required. When the liquid level height reaches the prescribed height H, the feed of the diluent is stopped, and the volume of this liquid is set to V. Compressed air is jetted into the dilution chamber 11 from an air injection hole 14a through an air feed pipe 14 to stir the sample and diluent in the dilution chamber 11. The diluted sample diluted to Vh /V is prepared. The solenoid valve SV3 is finally opened, and the prepared diluted sample is taken out through a diluted sample discharge pipe 13.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a dilution tank and a dilution apparatus using the same. More particularly, the present invention relates to a diluting tank for collecting a fixed amount of a sample and adding a predetermined amount of a diluent thereto to dilute the sample. In particular, the present invention relates to a diluting apparatus for collecting a predetermined amount of an aqueous sample and diluting the sample by adding pure water or ion-exchanged water thereto.

[0002]

2. Description of the Related Art In thermal power plants and nuclear power plants, the concentrations of phosphate ions, iron ions and silica in circulating water are measured to control the quality of circulating water.

[0003] Phosphate ions and the like contained in samples such as circulating water,
When measuring the concentration of a specific component, the collected sample should be
Usually, the measurement is performed after diluting to an appropriate magnification with pure water or ion-exchanged water.

Conventionally, for example, a dilution / measurement apparatus shown in FIG. 15 has been used to dilute a collected sample and measure the concentration of a specific component. Hereinafter, this device will be described.

In this apparatus, as shown in FIG. 15, a first measuring tank 2 'for measuring a sample to a set amount and pure water used for diluting the sample are set. And a sample weighed in the first weighing tank 2 'and a pure water weighed in the second weighing tank 3' to prepare a diluted sample. Mixing tank 1 ',
It has a measuring tank 5 'for measuring the concentration of a specific component contained in the diluted sample, and a drain discharge pipe 51' for discharging the diluted sample after measuring the concentration of the component in the measuring tank 5 'to the outside. ing. At the bottom of the first measuring tank 2 'and at the bottom of the second measuring tank 3', a sample supply pipe 21 'for supplying the measured sample to the mixing tank 1' and the measured pure water to the mixing tank 1 '. The pure water supply pipes 31 'are connected to each other, and the sample supply pipes 21' and the pure water supply pipes 31 'merge into one and are led to the mixing tank 1'. The sample supply pipe 21 '
And the pure water supply pipe 31 ′ are each provided with a valve V1 on the way.
And V2. Further, at the bottom of the mixing tank 1 ',
The diluted sample discharge pipe 13 'for discharging the diluted sample is connected, and the other end of the diluted sample discharge pipe 13' is connected to the measuring tank 5 '. A drain pipe 51 'for discharging the diluted sample after the measurement is connected to the measuring tank 5'. Incidentally, a valve V3 is provided in the middle of the diluted sample discharge pipe 13 '. Also, a valve V is provided in the middle of the drain discharge pipe.
4 are provided.

[0006] A sample such as circulating water in a thermal power plant or a nuclear power plant is guided to a first measuring tank 2 'and measured to a set amount. When the sample is measured in the first measuring tank 2 ', the valve V1 is opened, and the measured sample is introduced into the mixing tank 1 through the sample supply pipe 21'.

On the other hand, pure water used for diluting the sample is guided to the second measuring tank 3 'and measured to a predetermined amount. When pure water is measured in the second measuring tank 3 ',
The valve V2 is opened, and the measured pure water is supplied to the pure water supply pipe 31 '.
Into the mixing vessel 1 '.

The sample and pure water introduced into the mixing tank 1 'are stirred and mixed by a stirring means (not shown) provided in the mixing tank 1', whereby a diluted sample is prepared. Further, a coloring agent which reacts with the component to be measured to form a color is injected into the mixing tank 1 'through a metering pump (not shown).

A diluted sample is prepared in the mixing tank 1 ',
When the coloring agent is injected into the diluted sample, the valve V3 is opened, and the diluted sample is introduced into the measuring tank 5 'through the diluted sample discharge pipe 13'. The means determines the concentration of the component. The diluted sample measured in the measuring tank 5 'is discharged as drain through a drain discharge pipe 51'.

[0010]

In the above apparatus, as described above, since the sample and pure water are mixed after being measured in the measuring tank, it takes a long time to prepare a diluted sample. was there.

When a sample and pure water are introduced from each measuring tank into the mixing tank, a part of the sample and pure water often remain in the piping. Only a smaller amount of sample and pure water than the weighed amount is introduced into the mixing tank, and therefore the measured values vary widely even if the same sample was diluted by the same factor to prepare a diluted sample. There were many.

Further, in the above-mentioned apparatus, two measuring tanks, one mixing tank and one measuring tank are required, so that
There is also a problem that the device is complicated and large.

An object of the present invention is to provide a dilution tank which solves the above-mentioned problems of the conventional dilution / measurement apparatus and a dilution apparatus using the dilution tank.

[0014]

Means for solving the above problems are as follows. (1) A dilution chamber for mixing a liquid sample and a diluent for diluting the sample is formed inside. A dilution tank main body, a sample discharge means having a sample discharge port opened to a predetermined height from the bottom of the dilution chamber, and a sample discharge stop means for stopping discharge of the sample from the sample discharge port. (2) the sample discharging means in (1) has a sample discharging pipe having an open sample discharging port at one end, and the sample discharging stopping means in (1) includes: The dilution tank according to (1), which has a valve provided in the middle of the sample discharge pipe, and (3) the sample discharge pipe in (2) is a pipe having a sample discharge opening opened upward. (2) the dilution tank described in (2), (4) the sample in (2) above. The outlet pipe is a siphon pipe, the dilution tank according to (2), and (5) the dilution chamber in (1) is a constant volume chamber having a predetermined internal volume and opening upward. The dilution tank according to any one of (1) to (4), wherein the sample outlet in (1) is substantially at the same height as the upper end of the constant volume chamber; (6) The dilution tank body according to any one of (1) to (5), wherein the dilution tank body in (1) is at least partly made of a transparent material, (7) any of (1) to (6). , A sample supply means for supplying a sample to a dilution chamber of the dilution tank, a sample supply stop means for stopping supply of the sample from the sample supply means, and a dilution for supplying a diluent to the dilution chamber. Liquid supply means, and diluent supply stop for stopping the supply of diluent from the diluent supply means And the stage,
A diluted sample discharging means provided at the bottom of the dilution chamber for discharging a diluted sample obtained by mixing a sample and a diluting liquid; and a diluted sample discharging means for stopping the discharging of the diluted sample from the diluted sample discharging means. (8) The liquid level in the dilution chamber has reached a predetermined height at a position higher than the sample discharge port provided in the dilution chamber in (7). (7) The dilution device according to (7), further comprising a liquid level detecting means for detecting the fact that (9) the liquid level detecting means in (8) is a means for optically detecting the liquid level. And (10) the liquid level detecting means in (8), when detecting that the liquid level in the dilution chamber has reached a predetermined height, activates the diluting liquid supply stopping means in (7). To stop the supply of diluent to the dilution chamber. A diluter according to the configuration composed of (8).

[0015]

FIG. 1 is a perspective view showing one embodiment of a dilution tank according to the present invention, and FIG. 2 is a longitudinal section taken along a plane AA of the dilution tank shown in FIG. FIG.

In the dilution tank 1 shown in FIG.
Has a substantially cylindrical shape and is made of a transparent acrylic resin. Here, the dilution tank main body 10 is a part that forms the main body of the dilution tank, in which a dilution chamber 11 described later is formed and a sample discharge pipe 12 described later is formed.
Refers to the part to which is attached.

Inside the dilution tank main body 10, there is formed a cylindrical dilution chamber 11 for mixing a liquid sample and a diluent for diluting the sample.

As shown in FIG. 1 and FIG.
A sample discharge pipe 12 for discharging a sample penetrates a bottom portion of the dilution chamber 11, and the sample discharge pipe 12 protrudes from the bottom of the dilution chamber 11 by a predetermined height h. The sample outlet 12a is open. An electromagnetic valve SV4 is provided in the middle of the sample discharge pipe 12. Here, the bottom of the dilution chamber 11 refers to the lowest part of the dilution chamber 11.

A dilution chamber 1 is provided at the bottom of the dilution tank body 10.
A diluent discharge pipe 13 for discharging the diluent prepared in 1 is attached, and an electromagnetic valve SV3 is provided in the middle of the diluent discharge pipe 13.

An air supply pipe 14 is further attached to the bottom of the dilution tank main body 10, and the upper end thereof is an air ejection hole 14a.

A sample supply pipe 21 and a diluent supply pipe 31 penetrate the upper part of the wall of the dilution tank main body 10.

In the dilution tank 1 shown in FIGS. 1 and 2, the dilution chamber 11 corresponds to the dilution chamber in the dilution tank of the present invention. The sample discharge pipe 12 corresponds to a sample discharge means in the dilution tank of the present invention, and the sample discharge port 12a corresponds to a sample discharge port in the dilution tank of the present invention. And SV4
Corresponds to the sample discharge stopping means in the dilution tank of the present invention, and the air supply pipe 14 and the air ejection hole 14a correspond to the stirring means in the dilution tank of the present invention.

The procedure for preparing a diluted sample using the dilution tank 1 shown in FIGS. 1 and 2 will be described below.

First, the solenoid valve SV3 is closed and the solenoid valve SV4 is closed.
The sample is supplied to the dilution chamber 11 in a state where is opened. Until the height of the liquid surface from the bottom of the dilution chamber 11 becomes equal to the height h of the sample discharge pipe 12 protruding from the bottom of the dilution chamber 11, the sample accumulates inside the dilution chamber 11. The plane also rises. When the height of the liquid surface in the dilution chamber 11 reaches the height h, the supplied sample is removed from the sample outlet 12a.
From the dilution chamber 1 through the sample discharge pipe 12 to the outside.
No more samples accumulate in 1. Therefore, the liquid level does not exceed h. When the sample starts to be discharged from the sample discharge pipe 12, the supply of the sample is stopped, and the solenoid valve S
Close V4. The volume of the sample at this time is V _h.

Next, a diluent is supplied into the dilution chamber 11,
Further, if necessary, a coloring agent which reacts with the component to be measured to form a color is supplied. When the liquid level in the dilution chamber 11 reaches a predetermined height H higher than the height h, the supply of the diluent is stopped. At this time, the volume of the liquid present in the dilution chamber 11 is set to V.

After the supply of the diluting liquid is stopped, compressed air is supplied through the air supply pipe 14, and the compressed air is jetted from the air injection hole 14a into the dilution chamber 11, thereby causing the dilution chamber 1
1 Stir the sample and diluent inside. As a result, a diluted sample diluted with the diluent to V _h / V of the original sample is prepared.

Finally, the solenoid valve SV3 is opened, and the prepared diluted sample is taken out through the diluted sample discharge pipe 13.

Hereinafter, each component of the dilution tank of the present invention will be described in detail.

In the dilution tank of the present invention, the dilution chamber is a space formed in the dilution tank main body, and includes a liquid sample,
The diluent for diluting the sample is introduced into the dilution chamber and mixed. Here, the dilution tank body is, as described above,
A part that forms the main body of the dilution tank and has a dilution chamber formed therein and a part to which sample discharging means and the like are attached.

In the dilution tank of the embodiment shown in FIGS. 1 and 2, the shape of the dilution chamber is cylindrical, but the shape of the dilution chamber is not limited to a cylinder. As the shape of the dilution chamber,
In addition to the cylindrical shape, for example, there is a conical shape or a truncated conical shape that is convex downward. In addition, a shape such as a cylindrical shape, a prism shape, or a truncated pyramid shape having a conical surface with a convex bottom at the bottom is also possible. Shapes such as a spherical shape and an ellipsoidal shape, and shapes having a constriction such as a gourd shape are also possible.

Further, a part of the dilution chamber may be a constant volume chamber having a predetermined internal volume and opening upward. When a constant volume chamber is provided in part of the dilution chamber, the constant volume chamber is preferably provided at the bottom of the dilution chamber, and the area of the opening of the constant volume chamber is such that the dilution chamber is larger than the constant volume chamber. Is preferably smaller than the horizontal cross-sectional area of the upper part. If the constant volume chamber is configured as described above, a higher dilution ratio can be obtained in a dilution tank having the same volume. Also, if the area of the opening of the constant volume chamber is small, the fluctuation of the liquid level is also small, so that a quantitative error due to vibration can be reduced.

As the sample discharging means, a sample discharging pipe for discharging a predetermined amount or more of the sample to the outside can be used. As the sample discharge tube, like the sample discharge tube of the dilution tank,
A tube having an upper or side-facing opening at the upper end projecting upward from the bottom or lowest part of the dilution chamber can be used. Here, as a tube having an opening directed to the side at the upper end, for example, a tube curved in an inverted L-shape as a whole can be mentioned. Further, a siphon tube can also be used as the sample discharge tube. In particular, when a siphon tube is used as the sample discharge tube, the measured sample does not flow out of the dilution tank through the sample discharge tube after the completion of the measurement, so that the dilution can be performed with higher accuracy. Here, the siphon tube may include a tube curved in an inverted U-shape or an inverted J-shape as a whole. In addition, when using a sample discharge tube having an opening facing upward or sideward at the upper end, which projects upward from the bottom of the dilution chamber, that is, the bottommost portion, a thin tube is used as the sample discharge tube. This is preferable because errors due to the sample remaining in the sample discharge pipe can be reduced.

The sample discharging means is preferably a sample discharging hole formed in the wall surface of the dilution tank body. A gutter or a pipe may be connected to the opening of the sample discharge hole outside the dilution tank main body so that the sample overflowing from the opening does not flow down the outer wall of the dilution tank.

However, in these sample discharge tubes, the height h of the opening must be lower than the height of the dilution chamber. When a sample supply pipe and a diluent supply pipe described later are provided in the dilution tank, the opening is higher than any of the sample supply pipe and the diluent supply pipe. Is preferably low. Further, when a part of the dilution chamber is a constant volume chamber, the height of the opening is preferably the same as the height of the upper end of the constant volume chamber.

Here, the height of the opening means the height of the opening end itself when the sample discharging means is a sample discharging pipe and the opening of the sample discharging pipe is directed upward or downward. When the opening of the sample discharge tube faces sideways, it refers to the height of the lowermost end of the opening. When the sample discharging means is a sample discharging hole perforated on the wall surface of the dilution tank main body, it means the height of the lowermost end of the sample discharging port opened on the inner wall of the dilution chamber.

When a sample discharge pipe is used as the sample discharge means, a valve can be provided in the sample discharge pipe as a sample discharge stop means. Various types of valves can be used as the valve, and examples of such a valve include a stop valve, a gate valve, a butterfly valve, a ball valve, a three-way valve, and a cock. These valves may be manually operated, electromagnetically operated valves such as electromagnetic valves, or hydraulically or pneumatically operated valves. Further, a pinch cock may be used in place of the valve.

On the other hand, when the sample discharge hole is used as the sample discharge means, the sample discharge stop means is provided near the sample discharge port opened on the wall surface of the dilution chamber. An open / close plate can be used. Further, when a pipe is connected to the outside of the sample discharge hole, a valve can be inserted as a sample discharge stop means in the middle of the pipe, as in the case of the sample discharge pipe. As the valve, the same valve as in the case of the sample discharge pipe is used.

The dilution tank may further have various stirring means.

As such a stirring means, there is a stirring means utilizing a stirring action of gas injected into the liquid. As such a stirring means, for example, as in the stirring means shown in FIGS. 1 and 2, a gas such as air is injected into a dilution chamber from a gas ejection port provided at the bottom of the dilution chamber. There is a stirring means for stirring the sample and the diluent. The gas injected from the gas outlet may be any gas that does not substantially dissolve in the sample and the diluent and does not react. As such a gas,
Air and inert gases such as nitrogen gas and argon gas.

As the stirring means, in addition to the above, stirring means for irradiating ultrasonic waves to perform stirring may be used. As such a stirring means, for example, there is a stirring means in which an ultrasonic oscillator is provided on the inner wall of the dilution chamber or on the surface of the dilution tank main body. In this stirring means, the sample and the diluent in the dilution chamber are stirred by the ultrasonic waves emitted from the ultrasonic oscillator.

Further, as the stirring means, mechanical stirring means such as a propeller type stirrer, a turbine type stirrer and a reciprocating rotary stirrer are preferably used.

As the material of the dilution tank main body, any material can be used as long as precision processing is possible and the material is not affected by the sample and the diluent. Examples of such materials include stainless steel, phosphor bronze, aluminum bronze, beryllium bronze, high nickel steel, nickel-based high corrosion resistant alloys, ceramics, glass, and various synthetic resins.
Then, different materials may be used for the bottom portion and the side surface of the dilution tank main body. However, when a means for optically detecting the liquid level is used as the liquid level detecting means described later, it is preferable that light can pass through the side surface of the dilution tank main body. It is preferably made of a transparent material such as a resin, an acrylic resin, a polycarbonate resin, and a hard polyvinyl chloride resin.

Hereinafter, another example of the dilution tank of the present invention will be described.

FIG. 3 is a perspective view showing an example of a dilution tank in which the sample discharge means has a sample discharge hole perforated in the wall of the dilution tank main body. FIG. 4 is a plan view of the dilution tank shown in FIG. A-A
It is sectional drawing which shows the longitudinal cross section cut | disconnected along.

In the dilution tank 1 shown in FIG.
Numeral 0 has a substantially cylindrical shape and is formed of a transparent acrylic resin. A cylindrical dilution chamber 11 is formed inside the dilution tank main body 10.

A diluent discharge pipe 13 for discharging the diluent prepared in the diluting chamber 11 is attached to the bottom of the diluting tank main body 10, similarly to the diluting tank of FIG.
Is provided with a solenoid valve SV3.

An air supply pipe 14 is further attached to the bottom of the dilution tank main body 10, and the upper end thereof is an air ejection hole 14a.

A sample supply pipe 21 and a diluent supply pipe 31 penetrate the upper part of the wall of the dilution tank body 10 as in the dilution tank of FIG.

The sample discharge hole 12 is provided in the wall of the dilution tank main body 10.
b is bored, and one end of the sample discharge hole 12b is a sample discharge port 12a opened on the wall surface of the dilution chamber 11. A tube 12c is connected to the other end of the sample discharge hole 12b. An electromagnetic valve SV4 is provided in the middle of the pipe 12c. The sample discharge hole 12b is perforated so that the height from the bottom of the dilution chamber 11 to the lowermost end of the sample discharge port 12a is a predetermined height h.

In the dilution tank 1 shown in FIGS. 3 and 4, the dilution chamber 11 corresponds to the dilution chamber in the dilution tank of the present invention. The sample discharge hole 12b and the pipe 12c correspond to the sample discharge means in the dilution tank of the present invention, and the sample discharge port 12a
Corresponds to the sample outlet in the dilution tank of the present invention. SV4 corresponds to a sample discharge stopping means in the dilution tank of the present invention, and the air ejection hole 14a corresponds to a stirring means in the dilution tank of the present invention.

The procedure for preparing a diluted sample using the dilution tank 1 shown in FIGS. 3 and 4 will be described below.

First, the solenoid valve SV3 is closed and the solenoid valve SV4 is closed.
The sample is supplied to the dilution chamber 11 in a state where is opened. The height of the liquid surface measured from the bottom of the dilution chamber 11 corresponds to the sample outlet 12a.
Until the height h of the lowermost edge of
The liquid level also rises because it accumulates inside 1. And dilution chamber 1
When the liquid level in the sample 1 reaches the height h, the supplied sample is supplied from the sample outlet 12a to the sample outlet 12b and the tube 1.
It is discharged outside through 2c and does not accumulate in the dilution chamber 10. Therefore, the liquid level does not exceed h.
When the sample starts to be discharged from the pipe 12c, the supply of the sample is stopped, and the solenoid valve SV4 is closed. The volume of the sample at this time is V _h.

Next, a diluent is supplied into the dilution chamber 11,
Further, if necessary, a coloring agent which reacts with the component to be measured to form a color is supplied. When the liquid level in the dilution chamber 11 reaches a predetermined height H higher than the height h, the supply of the diluent is stopped. The volume of the liquid present in the dilution chamber 11 at this time is V.

After the supply of the diluting liquid is stopped, compressed air is supplied through the air supply pipe 14 and the compressed air is ejected from the air injection hole 14a into the dilution chamber 11, thereby causing the dilution chamber 1
1 Stir the sample and diluent inside. As a result, a diluted sample diluted with the diluent to V _h / V of the original sample is prepared.

Finally, the solenoid valve SV3 is opened, and the prepared diluted sample is taken out through the diluted sample discharge pipe 13.

FIG. 5 is a perspective view showing an example of a dilution tank in which a part of the dilution chamber is a constant volume chamber. FIG. 6 is a sectional view of the dilution tank shown in FIG. It is sectional drawing which shows the vertical cross section.

A diluent discharge pipe 13 for discharging the diluent prepared in the diluting chamber 11 is attached to the bottom of the diluting tank main body 10, similarly to the diluting tank of FIG.
Is provided with a solenoid valve SV3.

An air supply pipe 14 is further attached to the bottom of the dilution tank main body 10, and the upper end thereof is an air ejection hole 14a.

A sample supply pipe 21 and a diluent supply pipe 31 penetrate the upper part of the wall of the dilution tank main body 10, similarly to the dilution tank of FIG.

Also in the dilution tank 1 shown in FIG. 5, the dilution tank main body 10 has a substantially cylindrical shape and is made of a transparent acrylic resin. And the dilution tank body 1
A substantially cylindrical dilution chamber 11 is formed inside the chamber 0. At the bottom of the dilution chamber 11, a constant volume chamber 11a is formed. The constant volume chamber 11a has a cylindrical shape, the diameter is smaller than the upper cylindrical portion of the dilution chamber 11, and the upper end of the constant volume chamber 11a extends from the bottom of the constant volume chamber 11a, that is, the bottom of the dilution chamber 11. The height up to is h. Constant volume chamber 11a
A conical surface 11b that expands upward is formed between the upper portion of the dilution chamber 11 and the cylindrical portion.

A sample discharge pipe 12 for discharging a sample passes through the bottom of the dilution tank main body 10. The sample discharge pipe 12 protrudes from the bottom of the constant volume chamber 11a by a height h, and the upper end thereof is the same as the upper end of the constant volume chamber 11a. At an upper end of the sample discharge pipe 12, a sample discharge port 12a is opened upward. An electromagnetic valve SV4 is provided in the middle of the sample discharge pipe 12.

The procedure for preparing a diluted sample using the dilution tank 1 shown in FIGS. 5 and 6 will be described below.

First, the solenoid valve SV3 is closed and the solenoid valve SV4
The sample is supplied to the dilution chamber 11 in a state where is opened. Until the height of the liquid level measured from the bottom of the dilution chamber 11 becomes equal to the height h of the constant volume chamber 11a, the sample accumulates inside the dilution chamber 11, so that the liquid level also rises. When the liquid level in the dilution chamber 11 reaches the height h, the supplied sample is discharged from the sample discharge port 12a to the outside through the sample discharge pipe 12, and does not accumulate in the dilution chamber 10. Therefore, the liquid level does not exceed the height h of the constant volume chamber 11a. Tube 1
When the sample starts to be discharged from 2c, the supply of the sample is stopped, and the solenoid valve SV4 is closed. Here, when the volume of the constant-volume chamber 11a and V _h, the volume of the sample at this time also becomes V _h.

Next, a diluent is supplied into the dilution chamber 11,
Further, if necessary, a coloring agent which reacts with the component to be measured to form a color is supplied. The liquid level in the dilution chamber 11 is high. When reaching a predetermined height H higher than the height h, the supply of the diluent is stopped. The volume of the liquid present in the dilution chamber 11 at this time is V.

When the supply of the diluting liquid is stopped, compressed air is supplied through the air supply pipe 14 and the compressed air is ejected from the air injection holes 14a into the inside of the dilution chamber 11.
1 Stir the sample and diluent inside. As a result, a diluted sample diluted with the diluent to V _h / V of the original sample is prepared.

Finally, the solenoid valve SV3 is opened, and the prepared diluted sample is taken out through the diluted sample discharge tube 13.

FIG. 7 is a perspective view showing an example of a dilution tank in which the sample discharge pipe 12 is a siphon tube in the dilution tank shown in FIGS. 5 and 6, and FIG. 8 is a dilution tank shown in FIG. FIG. 2 is a cross-sectional view showing a vertical cross section taken along a plane AA.

FIGS. 5 and 6
, A diluent discharge pipe 13 for discharging the diluent prepared in the diluting chamber 11 is attached,
An electromagnetic valve SV3 is provided in the middle of the diluent discharge pipe 13.

An air supply pipe 14 is further attached to the bottom of the dilution tank main body 10, and the upper end thereof is an air ejection hole 14a.

A sample supply pipe 21 and a diluent supply pipe 31 penetrate the upper part of the wall of the dilution tank main body 10 as in the case of the above-mentioned dilution tank.

The dilution tank 1 shown in FIG.
The 0 and the dilution chamber 11 have the same shape as the above-mentioned dilution tank, and are formed of a transparent acrylic resin. The same applies to the point that a constant volume chamber 11a is formed at the bottom of the dilution chamber 11. Further, the shape, diameter, and height of the constant volume chamber 11a are the same as those of the constant volume chamber in the dilution tank.

[0072] towards the interior of the wall of the dilution tank body 10 from the conical surface 11b, the siphon tube mounting hole 12B ₁ attaching the siphon tube 12A in the horizontal direction is drilled. Then, the inside of the wall of the dilution tank body 10, in the vertical direction, and the longitudinal hole 12B ₂ to intersect at right angles with the siphon tube mounting hole 12B ₁ is perforated. Portion and the siphon tube mounting hole 12B ₁ and longitudinal hole 12B ₂ intersect, the length of one side, siphon tube mounting hole 12
And has a cross-section 12B ₃ is a large cubic space than the diameter and the diameter of the longitudinal hole 12B ₂ of B _1. One end of the siphon tube 12A has a siphon tube mounting hole 12B.
_The other end is a tube bent downwards. The opening 12a of the siphon tube 12A is open downward at the lower end of the siphon tube 12A, and has substantially the same height as the upper end of the constant volume chamber 11a. h. The vertical hole 12B _2, exhaust pipe 12C for exhausting the sample is inserted into the external, the discharge pipe 12
A solenoid valve SV4 is provided in the middle of C. In this dilution tank, siphon tube 12A, the siphon tube mounting hole 12B _1, the vertical hole 12B _2, intersection 12B _3, and the discharge pipe 12C corresponds to the sample discharge pipe 12.

The liquid sample that can be diluted in the dilution tank of the present invention includes, for example, circulating water in a thermal power plant and a nuclear power plant. Samples obtained by sampling at a manufacturing plant, a food manufacturing plant, and the like are also included. Further, various waste liquids discharged from factories and non-aqueous samples such as hydrocarbon fuel oil and lubricating oil are also included in the liquid sample.

As the diluent, tap water, pure water and ion-exchanged water are used if the liquid sample is aqueous, and various organic solvents are used if the liquid sample is non-aqueous. The organic solvent used as the diluent may be selected from aliphatic hydrocarbon solvents, aromatic hydrocarbon solvents, halogenated aliphatic hydrocarbon solvents, halogenated aromatic hydrocarbon solvents, and alcohols, depending on the properties of the sample. It can be selected from system solvents, ether solvents, amine solvents, amide solvents such as dimethylformamide, and pyrrolidone solvents such as N-methylpyrrolidone.

Next, the dilution apparatus of the present invention will be described.

FIG. 9 is a piping diagram showing an example of the dilution device of the present invention.

In the dilution device shown in FIG. 9, the dilution tank 1 has the same mode as the dilution tank 1 shown in FIGS. 7 and 8. That is, the dilution tank main body 10 is entirely made of an acrylic resin, and a part of the dilution chamber 11 formed inside the dilution tank main body 10 is a constant volume chamber 11a. The sample discharge pipe 12 is provided at the lower part of the dilution tank main body 10.
Is penetrating. The sample discharge tube 12 is a siphon tube 12A
The opening 12a of the siphon tube 12A has substantially the same height as the upper end of the constant volume chamber 11a. The sample discharge pipe 12 is provided with an electromagnetic valve SV4, and the sample discharge pipe 12 is provided with a detector 6 downstream of the solenoid valve SV4. The detector 6 is a detector that optically detects that the sample has passed through the sample supply tube 12. The detector 6 is electrically connected so as to close a solenoid valve SV1 provided in a sample supply pipe 21, which will be described later, when detecting the sample discharged from the sample discharge pipe 12.

A sample supply pipe 21 for supplying a sample to the dilution chamber 11 and a diluent supply pipe 31 for supplying a diluent to the dilution chamber 11 are provided above the dilution tank 1. The other ends of the sample supply pipe 21 and the diluent supply pipe 31 are connected to the sample storage tank 2 and the diluent storage tank 3, respectively. Here, the sample storage tank 2 is a container for temporarily storing the collected sample, and the diluent storage tank 3 is a container for storing the diluent. The sample supply pipe 21 and the diluent supply pipe 31 include:
Solenoid valves SV1 and SV2 are inserted in the middle of each. In the diluent supply pipe 31, the solenoid valve SV
A short-circuit tube 32 that short-circuits the diluent supply pipe 31 and a diluted sample discharge pipe 13 described below is branched from downstream of 2, and a solenoid valve SV6 is provided in the middle of the short-circuit pipe 32.

A dilution sample discharge pipe 13 is connected to the bottom of the dilution chamber 11. The diluted sample prepared in the dilution chamber 11 is taken out from the diluted sample discharge pipe 13. An electromagnetic valve SV3 is provided in the middle of the diluted sample discharge pipe 13.

In the diluting apparatus shown in FIG. 9, the diluted sample discharge pipe 13 is connected to the measuring tank 5, and in the measuring tank 5, a concentration of a predetermined component, for example, a phosphate ion in the diluted sample is measured. You. The measuring tank 5 is installed on the optical path of a colorimeter (not shown). In the colorimeter, the light emitted from the light source passes through the measuring tank 5 and is received by the light receiving unit. The measuring tank 5 is further provided with a drain discharge pipe 51 for discharging the diluted sample after the measurement to the outside of the diluting device. An electromagnetic valve SV7 is provided in the drain discharge pipe 51.

A light source 41 and a light detector 4 for detecting light from the light source 41 are provided outside the dilution tank main body 10. The light detector 4 is provided on the opposite side of the light source 41 with the dilution tank body 10 interposed therebetween, and the light detection is performed so that light emitted from the light source 41 is directly incident on a light receiving unit of the light detector 4. The position of the vessel 4 has been adjusted. The light source 41 and the photodetector 4 are mounted such that the optical path R is located at a height H from the bottom of the constant volume chamber 11a. The photodetector 4 and the solenoid valve SV2 are interlocked, and are configured so that when the light from the light source 41 is blocked and the light detection signal from the photodetector 4 becomes 0, the solenoid valve SV2 closes.

An air supply pipe 14 is further attached to the bottom of the constant volume chamber 11a.
Are connected to a compressed air tank 7. Air supply pipe 1
A solenoid valve SV5 is provided in the middle of 4.

In addition to the above, the diluting tank 1 is provided with a pipe for supplying a coloring agent which reacts with the component to be measured to form a color, for example, an ammonium vanadate solution and an ammonium molybdate solution if the component is a phosphate ion. However, this piping is not shown in FIG.

In the dilution apparatus shown in FIG. 9, the dilution tank 1 corresponds to the dilution tank in the dilution apparatus of the present invention. The sample storage tank 2 and the sample supply pipe 21 correspond to sample supply means in the dilution device of the present invention, and SV1 corresponds to sample supply stop means in the dilution device of the present invention. Further, the diluent storage tank 3 and the diluent supply pipe 31 correspond to the diluent supply means 31 in the diluting apparatus of the present invention, and V2 corresponds to the diluting liquid supply stopping means in the diluting apparatus of the present invention. The diluted sample discharge pipe 13 and the solenoid valve SV3 correspond to a diluted sample discharge unit and a diluted sample discharge stop unit in the dilution device of the present invention, respectively.

Hereinafter, the operation of the dilution device shown in FIG. 9 will be described.

FIG. 13 is a flowchart showing a flow of the operation of the diluting apparatus shown in FIG. In the dilution device of FIG. 9, before the start of dilution, all the solenoid valves SV1 to SV7 are in a closed state.

First, the solenoid valve SV1 provided on the sample supply pipe 21 and the solenoid valve SV4 provided on the sample discharge pipe 12 are opened, and the sample is supplied to the constant volume chamber 11a of the dilution tank 1. . The sample stored in the storage tank 2 flows down into the constant volume chamber 11a through the sample supply pipe 21 and the solenoid valve SV1. When the liquid level of the sample in the constant volume chamber 11a reaches the upper end of the constant volume chamber 11a having the height h, the liquid surface comes into contact with the opening 12a of the sample discharge pipe 12, and thereafter, the supplied sample Is discharged through the sample supply pipe 12. FIG. 10 shows the state of the diluting device shown in FIG. 9 at this time. When the detector 6 provided in the sample discharge pipe 12 detects the discharged sample, a signal from the detector 6 first detects the solenoid valve SV1.
Is closed, and then the solenoid valve SV4 is closed, whereby the supply of the sample is stopped.

When the supply of the sample is stopped, the solenoid valve SV2 provided on the diluent supply pipe 31 is opened, and the diluent is supplied into the diluting chamber 11. When the liquid level from the bottom of the constant volume chamber 11a in the dilution chamber 11 reaches H, the light source 4
The optical path R between 1 and the photodetector 4 is blocked by the liquid level. Therefore, the signal does not reach the light receiving portion of the photodetector 4, so that the photodetection signal from the photodetector 4 becomes zero. Thus, the solenoid valve SV2 is closed, and the supply of the diluent is stopped. The state of the dilution device shown in FIG. 9 at this time is shown in FIG.
Shown in If the component to be measured is colorless, such as phosphate ions, a color former that reacts with this component to develop a color is injected at this point.

After the diluent and the coloring agent are injected as required, the solenoid valve SV5 is opened, and air is jetted from the compressed air tank 7 through the air supply pipe 14 from the air jet port 14a. The sample, the diluent, and the coloring agent added as needed are stirred to prepare a diluted sample. FIG. 1 shows the state of the dilution device shown in FIG. 9 at this time.
It is shown in FIG.

After the preparation of the diluted sample, the solenoid valve SV5 is closed, the supply of air to the air outlet is stopped, and the stirring is completed.

After completion of the stirring, the solenoid valve SV3 provided on the diluted sample discharge pipe 13 and the solenoid valve SV7 provided on the drain discharge pipe 51 are opened, and the diluted sample in the dilution chamber is supplied to the measuring tank 5
The concentration of the target component is measured in the measuring tank 5 and discharged to the outside through the drain discharge pipe 51.

After the measurement in the measuring tank 5, the solenoid valves SV2,
SV3, SV4, SV6, and SV7 open, and dilution chamber 1
1. The diluent from the diluent storage tank 3 is supplied to the constant volume chamber 11a, the sample discharge pipe 12, the diluted sample discharge pipe 13, the measurement tank 5, and the drain discharge pipe 51.
1. The constant volume chamber 11a, the sample discharge pipe 12, the diluted sample discharge pipe 13, the measurement tank 5, and the drain discharge pipe 51 are washed.

Hereinafter, each component of the dilution apparatus of the present invention will be described in detail.

In the dilution apparatus of the present invention, any dilution tank according to the present invention can be used as the dilution tank. Examples of such a dilution tank include the dilution tanks shown in FIGS.

As the sample supply means, like the sample supply means in the diluting apparatus shown in FIGS. 9 to 12, a sample liquid storage tank for temporarily storing the collected sample, and a sample liquid storage tank A sample supply means having a sample supply pipe, which is a pipe for supplying a sample to the apparatus, can be used. As shown in FIGS. 9 to 12, an electromagnetic valve can be inserted into the sample supply pipe as a sample supply stop unit. As the sample supply stopping means, various valves such as a stop valve, a gate valve, a butterfly valve, a ball valve, a cock, and a three-way valve can be used. These valves may be manually operated, electromagnetically actuated, such as solenoid valves, or hydraulically or pneumatically actuated.
Further, a pinch cock may be used in place of the valve.

[0096] In addition to the above, the sample supply means may be a sample collection pipe for collecting a sample in a pipe such as a circulating water pipe in a thermal power plant or a nuclear power plant through which a liquid to be sampled flows. A sample return pipe for returning a sample to the pipe is provided, and the sample supply pipe, the sample collection pipe, and the sample return pipe are connected by a three-way valve, and a flow path from the sample collection pipe to a flow path leading to the sample supply pipe is provided. And two flow paths of the flow path leading to the sample return pipe. In the sample supply means of this aspect, the three-way valve corresponds to a sample supply stop means.

When the dilution tank has a sample discharge tube as in the diluting apparatus shown in FIGS. 9 to 12, a detector for detecting the sample is provided in the sample discharge tube, and the sample passes through the sample discharge tube. When the detector detects that the detection has been performed, the sample supply stopping means may be operated by a signal from the detector to stop the supply of the sample.

As the diluent supply means, like the diluent supply means in the above embodiment, a diluent storage tank for storing the diluent, and a diluent supply tank which is a pipe connecting the diluent storage tank and the diluting tank A diluent supply means having a tube can be used. In the diluent supply pipe, as in the above embodiment,
An electromagnetic valve can be inserted as the diluting liquid supply stopping means.

As the diluted sample discharging means in the dilution apparatus of the present invention, an embodiment having a diluting liquid discharging pipe provided at the bottom of the dilution tank main body, like the diluted sample discharging means in the above embodiment, is possible. The diluent discharge pipe may be provided with various valves such as a solenoid valve on the way as a means for stopping the dilution sample discharge. As such a valve, for example, various valves such as an electromagnetic valve can be used as described in the sample supply stopping means and the diluting liquid supply stopping means. still,
For example, as in the example of the dilution device shown in FIGS. 9 to 12, the sample discharge pipe can be connected to a measurement tank for measuring the concentration of the component to be measured in the diluted sample.

The diluting apparatus of the present invention may further include means for detecting that the liquid level in the diluting chamber has reached a predetermined height. As such means, a device for optically detecting the liquid level, a device for mechanically detecting the liquid level, a device for electrically detecting the liquid level, and the like can be used.

As a device for optically detecting the liquid level, for example, a light source mounted at a predetermined height as shown in FIGS. Provided is a device having a photodetector.
In this device, incandescent lamps, fluorescent lamps,
Various light sources such as a xenon lamp, a light emitting diode, and various laser oscillators are used. As the photodetector, various photodetectors or photodetectors utilizing a phototube can be used. In such a photodetector, a current flows while light is applied, and the current stops when the light is cut off. Thus, the liquid level can be detected.

Examples of a device for mechanically detecting the liquid level include a device having a small float floating on the liquid surface in the dilution chamber and a switch mechanically connected to the float by a push rod or a link. Can be In this device, when the float rises to a predetermined position, a switch connected to the float is turned off or on, so that the liquid level can be detected.

[0103] Other than this, there is an apparatus having a spring installed below the dilution tank and a switch that turns off or on when the amount of settlement of the dilution tank reaches a predetermined value. In this apparatus, since a spring is provided below the dilution tank, the diluting liquid is supplied to the dilution chamber, and when the weight of the dilution tank reaches a predetermined weight, the settling amount of the dilution tank also reaches a predetermined value. Thus, at this time, the switch is turned off or turned on, whereby it can be detected that the liquid level has reached a predetermined height.

As an apparatus for electrically detecting the liquid level, for example, two opposing electrodes provided at a predetermined height in a dilution chamber, an AC power supply for applying an AC current of a certain frequency to the electrodes, and the like. An apparatus having In this device, when the liquid level reaches a predetermined height, the two electrodes are immersed in the liquid, and the capacitance between the electrodes changes. By detecting this, the liquid level can also be detected.

In the diluting device of the present invention, the diluting liquid supply stopping means is operated when the liquid level detecting device issues a signal indicating that the liquid level is detected, so that the diluting liquid supply is stopped. be able to. As such a device, for example, a device having an electromagnetic valve as a diluting liquid supply stopping unit is used, and the electromagnetic valve and the liquid level detecting device are electrically connected to each other, and the liquid generated by the liquid level detecting device is discharged. There is a device configured to close an electromagnetic valve by an electric signal indicating that a surface has been detected.

Hereinafter, another embodiment of the dilution apparatus of the present invention will be described.

FIG. 14 shows a sample supply pipe for collecting a sample from a pipe from which a sample is to be collected and a sample collection pipe provided in the pipe in the dilution apparatus shown in FIG. A sample return pipe returning to the pipe, and a sample supply pipe for supplying a sample to a dilution chamber having a dilution tank, and the sample collection pipe, the sample return pipe, and the sample supply pipe are connected by a three-way valve. FIG. 2 is a piping diagram illustrating an example of a diluting device using a sample supply device including:

In the diluting apparatus shown in FIG. 14, similarly to the diluting apparatus shown in FIG. 9, the diluting tank 1 has the same mode as the diluting tank 1 shown in FIGS. That is, the dilution tank main body 10 is entirely made of an acrylic resin, and a part of the dilution chamber 11 formed inside the dilution tank main body 10 is a constant volume chamber 11a.

A sample supply pipe 21 for supplying a sample to the dilution chamber 11 is provided above the dilution tank 1. The sample supply pipe 21 is connected to the sample collection pipe 2 via the three-way valve SVT1.
2 and the sample return pipe 23. Here, the sample collection pipe 22 is a pipe for collecting a sample that is branched from a pipe 24 through which a liquid to be collected as a sample flows, and the sample return pipe 23 is a sample collected from the sample collection pipe 22. Is returned to the pipe 24. Three-way valve SVT1
Connects the sample collection tube 22 to either the sample supply tube 21 or the sample return tube 23, and causes the flow path from the pipe 24 to reach the dilution chamber 11 from the sample collection tube 22 through the sample supply tube 21. This is a valve for switching to any one of a flow path and a flow path returning from the sample collection pipe 22 to the pipe 24 through the sample return pipe 23. The dilution chamber 11 has the same configuration as the dilution device shown in FIG.
A diluent supply pipe 31 is provided. The other end of the diluent supply pipe 31 is connected to the diluent storage tank 3. An electromagnetic valve SV2 is inserted in the diluent supply pipe 31 in the middle. In the diluent supply pipe 31, the solenoid valve SV
2, the diluent supply pipe 31 and the diluted sample discharge pipe 13
A short-circuit tube 32 that short-circuits the two is branched, and an electromagnetic valve SV6 is provided in the middle of the short-circuit tube 32.

The sample discharge pipe 12 is provided at the bottom of the dilution tank main body 10.
Penetrates, and the sample discharge pipe 12 is
2A. Opening 12a of siphon tube 12A
Is substantially the same height as the upper surface of the constant volume chamber 11a. The sample discharge pipe 12 is provided with an electromagnetic valve SV4, and the sample discharge pipe 12 is provided with a detector 6 downstream of the solenoid valve SV4. The detector 6 is a detector that optically detects that the sample has passed through the sample supply tube 12. When the detector 6 detects the sample discharged from the sample discharge pipe 12, the three-way valve SVT1 is connected so that the sample collection pipe 22 connected to the sample supply pipe 21 is connected to the sample return pipe 23. Switch.

A dilution sample discharge pipe 13 is connected to the bottom of the dilution chamber 11, similarly to the dilution apparatus shown in FIG. The diluted sample prepared in the dilution chamber 11 is taken out from the diluted sample discharge pipe 13. An electromagnetic valve SV3 is provided in the middle of the diluted sample discharge pipe 13.

In the diluting apparatus shown in FIG. 9, the diluted sample discharge pipe 13 is connected to the measuring tank 5, and in the measuring tank 5, a concentration of a predetermined component, for example, a phosphate ion in the diluted sample is measured. . The measuring tank 5 is installed on the optical path of a colorimeter (not shown). In the colorimeter, the light emitted from the light source passes through the measuring tank 5 and is received by the light receiving unit. The measuring tank 5 is further provided with a drain discharge pipe 51 for discharging the diluted sample after the measurement to the outside of the diluting device. In the middle of the drain discharge pipe 51, the solenoid valve SV7
Is provided.

A light source 41 and a photodetector 4 are mounted outside the dilution tank main body 10 such that an optical path R is located at a height H from the bottom of the constant volume chamber 11a. The light detector 4 and the solenoid valve SV2 are interlocked with each other, so that when the light from the light source 41 is blocked and the light detection signal from the light detector 4 becomes 0, the solenoid valve SV2 is closed.

An air supply pipe 14 is further attached to the bottom of the constant volume chamber 11a.
Are connected to a compressed air tank 7. Air supply pipe 1
A solenoid valve SV5 is provided in the middle of 4.

In addition to the above, a pipe for supplying a coloring agent is provided in the dilution tank 1, but this pipe is not shown in FIG.

In the dilution apparatus shown in FIG. 14, the dilution tank 1
It corresponds to the dilution tank in the dilution device of the present invention. Piping 24
And the sample collection tube 22 and the sample supply tube 21 correspond to a sample supply unit in the dilution device of the present invention, and the three-way valve SVT1 is
It corresponds to a sample supply stopping means in the dilution device of the present invention. And the diluent storage tank 3 and the diluent supply pipe 31 correspond to the diluent supply means 31 in the diluting apparatus of the present invention,
V2 corresponds to the sample supply stopping means and the diluting liquid supply stopping means in the dilution device of the present invention. The diluent discharge pipe 13 and the SV3 correspond to a diluted sample discharge means and a diluted sample discharge stop means in the dilution device of the present invention, respectively.

The operation of the dilution device shown in FIG. 14 will be described below.

In the diluting apparatus shown in FIG. 14, before the start of dilution, the three-way valve SVT1 is connected to the sample collection pipe 22 and the sample return pipe 2
3 are connected to each other, and the solenoid valves SV2 to SV7 are closed.

First, the three-way valve SVT1 is switched to a position where the sample collection pipe 22 and the sample supply pipe 21 are connected, and the solenoid valve SV4 is opened. Thereby, the dilution tank 1
Is supplied to the constant volume chamber 11a. The sample flowing through the pipe 24 flows down into the constant volume chamber 11a through the sample collection pipe 22, the three-way valve SVT1, and the sample supply pipe 21. The constant volume chamber 1 in which the liquid level of the sample in the constant volume chamber 11a is the height h
1a, the opening 12a of the sample discharge pipe 12
Then, the liquid surface comes into contact with the liquid surface, and thereafter, the supplied sample is discharged through the sample supply pipe 12. When the detector 6 provided in the sample discharge pipe 12 detects the discharged sample, the SVT 1 is first switched again by a signal from the detector 6, and the sample collection pipe 22 and the sample return pipe 23 are connected. Then, the connection between the sample collection tube 22 and the sample supply tube 21 is disconnected. Next, the SV4 is closed, whereby the supply of the sample is stopped.

When the supply of the sample is stopped, the solenoid valve SV2 provided on the diluent supply pipe 31 is opened, and the diluent is supplied into the diluting chamber 11. When the height of the liquid surface from the bottom surface of the constant volume chamber 11a in the dilution chamber 11 reaches H, the light source 4
1 and the photodetector 4, the liquid level is detected, and the solenoid valve SV
2 is closed and the supply of the diluent is stopped. If the component to be measured is colorless, such as phosphate ions, a color former that reacts with this component to develop a color is injected at this point.

After the diluent and the coloring agent are injected as required, the solenoid valve SV5 is opened, and air is jetted from the compressed air tank 7 through the air supply pipe 14 from the air jet port 14a. The sample, the diluent, and the coloring agent added as needed are stirred to prepare a diluted sample.

After preparing the diluted sample, the solenoid valve SV5 is closed, the supply of air to the air outlet is stopped, and the stirring is completed.

After completion of the stirring, the solenoid valve SV3 provided in the sample discharge pipe 13 and the solenoid valve SV7 provided in the drain discharge pipe 51 are opened, and the diluted sample in the dilution chamber is sent to the measuring tank 5, The concentration of the target component is measured within 5,
It is discharged from the drain discharge pipe 51 to the outside.

After completion of the measurement in the measuring tank 5, the solenoid valves SV2, SV2,
SV3, SV4, SV6, and SV7 open, and dilution chamber 1
1. The diluent from the diluent storage tank 3 is supplied to the constant volume chamber 11a, the sample discharge pipe 12, the diluted sample discharge pipe 13, the measurement tank 5, and the drain discharge pipe 51.
1. The constant volume chamber 11a, the sample discharge pipe 12, the diluted sample discharge pipe 13, the measurement tank 5, and the train discharge pipe 51 are washed.

[0125]

EXAMPLE An example in which a dilution measurement of phosphate ions was performed using the dilution apparatus of the present invention and a measurement tank connected to the dilution apparatus will be described below.

The apparatus used in this example is a diluting apparatus having the configuration shown in FIG. The concentration of phosphate ions in the sample before dilution was 10 PPM, 30 PPM, 50 PPM.
M, 70 PPM and 100 PPM. The concentration of phosphate ions was measured by colorimetry using an ammonium molybdate solution as a color former and ascorbic acid as a reducing agent.

In this example, each sample was diluted with a diluting apparatus having the structure shown in FIG. 9 until colorimetric analysis could be performed, and the concentration of phosphate ions was measured. The phosphate ion concentration was measured for each diluted sample by 10
Each time, the maximum value, the minimum value, the average value, the standard deviation, and the ratio of the standard deviation to the average value were determined. Table 1 shows the results.

[0128]

[Table 1]

In Table 1, CvVALUE is a value indicating the ratio of the standard deviation to the average value in%.

As is clear from the above results, the dilution measurement of phosphate ions using the dilution apparatus of the present invention showed that a very high reproducibility of full scale ± 2% was obtained.

[0131]

In the dilution tank and the dilution apparatus using the same according to the present invention, the measurement and dilution of the sample and the diluent are performed in one dilution tank. Therefore, unlike a conventional dilution / measurement device, a fixed volume tank corresponding to each of a sample and a diluent is not required, so that the structure can be simplified and the size can be easily reduced. In addition, in the dilution tank and the dilution apparatus using the same according to the present invention, systematic errors caused by separately measuring the sample and the diluent are eliminated, so that high reproducibility in dilution measurement can be obtained.

[Brief description of the drawings]

FIG. 1 is a perspective view showing one embodiment of a dilution tank of the present invention.

FIG. 2 is a cross-sectional view showing a vertical cross section of the dilution tank shown in FIG. 1 taken along a plane AA.

FIG. 3 is a perspective view showing an example of a dilution tank in which a sample discharging unit has a sample discharging hole formed in a wall of a dilution tank main body.

FIG. 4 is a cross-sectional view showing a vertical cross section of the dilution tank shown in FIG. 3 taken along a plane AA.

FIG. 5 is a perspective view showing an example of a dilution tank in which a part of the dilution chamber is a constant volume chamber.

FIG. 6 is a cross-sectional view showing a vertical cross section of the dilution tank shown in FIG. 5 taken along a plane AA.

FIG. 7 is a perspective view showing an example of a dilution tank in which the sample discharge pipe 12 is a siphon tube in the dilution tank shown in FIGS. 5 and 6.

FIG. 8 is a cross-sectional view showing a vertical cross section of the dilution tank shown in FIG. 7 cut along a plane AA.

FIG. 9 is a piping diagram showing an example of the dilution device of the present invention.

FIG. 10 is a diagram showing a state in which the liquid level of the sample in the constant volume chamber 11a reaches the upper end of the constant volume chamber 11a having a height h and the supplied sample is the sample in the dilution device shown in FIG. FIG. 3 is a piping diagram showing a state of being discharged through a supply pipe 12.

11 shows a state in which the height of the liquid level from the bottom surface of the constant volume chamber 11a in the dilution chamber 11 reaches H and the supply of the diluent is stopped in the dilution apparatus shown in FIG. 9; FIG.

12 is a piping diagram showing a state in which air is jetted from an air jet port 14a in the diluting device shown in FIG. 9, and a sample, a diluent, and the like are stirred by the air.

FIG. 13 is a flowchart showing a flow of the operation of the diluting device shown in FIG. 9;

14 is a diagram showing a sample supply pipe for collecting a sample from a pipe from which a sample is to be collected, and a collected sample provided in the pipe as a sample supply means in the diluting apparatus shown in FIG. 9; And a sample supply pipe for supplying a sample to a dilution chamber of a dilution tank, and the sample collection pipe, the sample return pipe, and the sample supply pipe are connected by a three-way valve. FIG. 4 is a piping diagram illustrating an example of a diluting device using a sample supply device that has been manufactured.

FIG. 15 is a piping diagram showing an example of a conventional dilution / measurement device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Dilution tank, 1 '... Mixing tank, 2' ... First measuring tank, 3 '... Second measuring tank, 4 ... Photodetector,
5, 5 ': measuring tank, 6: detector, 10: dilution tank body, 11: dilution chamber, 11a: constant volume chamber,
12: sample discharge pipe, 12a: sample discharge port, 12
b: sample discharge hole, 12c: tube, 12A: siphon tube, 12B _1: siphon tube mounting hole,
12B ₂ ... vertical hole, 12B ₃ ... intersection, 12C
..Drain pipes, 13 and 13 '... Diluent discharge pipes
..Air supply pipes, 14a ... air ejection holes, 21, 2
1 ': sample supply pipe, 31: diluent supply pipe, 3
1 '... pure water supply pipe, 41 ... light source, 51, 51'
... Drain discharge pipes, V1, V2, V3, V4 ...
Valve, SV1, SV2, SV3, SV4, SV5, SV
6, SV7: Solenoid valve, SVT1: Three-way valve

Claims (10)

[Claims] 1. A dilution tank body having a dilution chamber formed therein for mixing a liquid sample and a diluent for diluting the sample, and a sample discharge opening at a predetermined height from the bottom of the dilution chamber. A dilution tank comprising: a sample discharging means having an outlet; and a sample discharging stopping means for stopping discharging of a sample from the sample discharging port. 2. The sample discharging means according to claim 1,
2. A sample discharge pipe having an open sample discharge port at one end, and the sample discharge stop means in claim 1 has a valve provided in the middle of the sample discharge pipe. The dilution tank described in 1. 3. The dilution tank according to claim 2, wherein the sample discharge tube in the second embodiment is a tube having a sample outlet opening upward. 4. The dilution tank according to claim 2, wherein the sample discharge pipe is a siphon pipe. 5. The dilution chamber according to claim 1, a part of which is a constant volume chamber having a predetermined internal volume and opening upward, and the sample discharge port according to claim 1 is: The dilution tank according to claim 1, wherein the dilution tank is substantially at the same height as an upper end of the constant volume chamber. 6. The dilution tank according to claim 1, wherein at least a part of the dilution tank body in the first embodiment is made of a transparent material. 7. A dilution tank according to any one of claims 1 to 6, sample supply means for supplying a sample to a dilution chamber of the dilution tank, and supply of the sample from the sample supply means is stopped. A diluting liquid supply means for supplying a diluting liquid to the diluting chamber; a diluting liquid supply stopping means for stopping a diluting liquid supply from the diluting liquid supplying means; and a diluting liquid supply stopping means provided at a bottom of the diluting chamber. A diluted sample discharging means for discharging a diluted sample obtained by mixing a sample and a diluting liquid, and a diluted sample discharging stopping means for stopping discharging of the diluted sample from the diluted sample discharging means. Features dilution equipment. 8. A liquid level detecting means for detecting that the liquid level in the dilution chamber has reached a predetermined height is provided at a position higher than the sample discharge port provided in the dilution chamber according to claim 7. The dilution device according to claim 7, 9. The liquid level detecting means according to claim 8,
9. The diluting device according to claim 8, wherein the diluting device is a means for optically detecting a liquid level. 10. The liquid level detecting means according to claim 8, upon detecting that the liquid level in the dilution chamber has reached a predetermined height, activates the diluting liquid supply stopping means according to claim 7, and The diluting device according to claim 8, wherein the supply of the diluting liquid to the diluting chamber is stopped.