JPH08226924A - Fluid module for automatic analizer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To analyze the concentration of a substance in a solution for only two or three minutes by using a very little amount of analysis flowing-out substance. SOLUTION: A fluid module for an automatic analyzer to determine the concentration of a substance in a solution is provided with a means for sampling a sample from the solution, a means that brings a sample solution into contact with a reagent and allows a substance including in the solution to react on the reagent, and a means that sends to an estimating device the concentration of the substance in the solution after the absorbance of a product during reaction is measured in a part of sample solution reacting on the reagent. Furthermore, it is provided with a first mechanism 10 to obtain a first diluted solution of the solution and a second mechanism 20 that adds a sample and diluent to the first diluted solution and supplies the obtained solution to a measuring device 31.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a fluidic module for an automated analyzer. It is used in particular to determine the concentration of hydrazine in solutions used in nuclear fuel reprocessing processes.

[0002]

BACKGROUND OF THE INVENTION Hydrazine is a compound used as a stabilizer in the nuclear fuel reprocessing process. At some stage of reprocessing, the hydrazine concentration of the solution has become an important factor both in the performance of the reprocessing process and the safety of the equipment. This factor is determined by laboratory spectroscopic analysis of samples taken during the process. The analysis is performed at various time intervals after sampling, which is an obstacle to the reproducibility of the measurements. This is because the reaction with hydrazine continues even in the sample after sampling. Furthermore, the amount sampled is not the minimum,
It unnecessarily increases the volume of active assay effluent.

The hydrazine concentration can be measured by Raman spectroscopy. However, this method is not sensitive.

Another method of interest is ion chromatography, which also provides a tool for hydroxylamine in the same sample. However, the chromatographic column regeneration time makes this method difficult to automate.

It is possible to determine the hydrazine concentration of a solution by the so-called DMAB (dimethylaminobenzaldehyde) method. The reaction carried out in this way is carried out as follows:

[0006]

Embedded image

The hydrazine obtained is a highly conjugated molecule, has an absorption peak at 455 nm and a large molecular extinction coefficient (about 60,000). That is, this reaction is very equilibrium. K:

[0008]

[Equation 1]

A quick measurement of the value of is that it is about 7
It shows that it is × 10 ^-3 . This requires measurement with a very large excess of aldehyde in order to make the amount of free hydrazine negligible. The ratio between DMAB and hydrazine concentrations for automated analysis has been fixed at about 15,000. When the concentration of hydrazine in the solution to be tested is about 0.2M,
This is 10,0 to obtain a measurable optical density.
A total dilution of 00 will be required. It has also been found that temperature has a large effect on the optical density value. Probably the constant K changes with temperature. Therefore, the system formed by the apparatus and the reagent can be maintained at a constant temperature.

[0010]

What the inventor of the present invention has attempted to obtain for the special case of hydrazine is that the amount produced in the form of the analytical effluent is very small, and that the sampling time and the analytical result are The device has a very short response time of 2-3 minutes in between, which prevents hydrazine from having sufficient reaction time to give erroneous results.

They are a continuous analyzer using the DMAB method, with an error of 1-2% and an almost negligible analytical effluent (1-2 μl of the total sample), and a hydrazine concentration of the solution of 2-3.
Designed a device that can give in a short time of minutes.

[0012]

SUMMARY OF THE INVENTION Accordingly, the present invention provides a means for sampling a portion of a solution in a fluidic module for an automated analyzer that allows the concentration of a substance in a solution to be determined. Means for contacting the collected sample solution with a reagent to react a substance contained in the sample solution with the reagent, and a portion of the sample solution reacted with the reagent, which is obtained during the reaction. In a fluid module comprising means for measuring the absorbance of a substance and sending it to a device for estimating the concentration of the substance in the solution, the fluid module sampling a defined amount of the solution. , A specified amount of diluent (dilution produc
t) and comprises a first mechanism for obtaining a first dilute solution of the solution, the fluid module samples a portion of the solution diluted by the first mechanism and determines it. It also comprises a second mechanism which makes it possible to add a quantity of a reagent and a determined quantity of a diluent to obtain a second diluted solution and then supply the resulting solution to the measuring device, The mechanism has a first two-position eight-way valve, two directions of which are connected to a first pipe and a second pipe of a solution sampling circuit, the two directions being of a fixed quantity. It is connected to a first means for storing liquid, one direction is connected to a pipe for supplying diluent, one direction is connected to a first pump, one direction called the outlet direction is a second direction. Connected to the mechanism, sealed in one direction, those connections are In the first position of the first valve, the first storage means is connected to the sampling circuit, the diluent supply pipe is connected in the sealed direction, the outlet direction is connected to the first pump, In the second position of the first valve, the first storage means is connected on the one hand to the first pump and on the other hand to the diluent supply pipe, the pipes of the sampling circuit being directly connected to one another and to the outlet. In which the direction is connected to the sealed direction, the second mechanism has a second two-position eight-way valve, two directions of which have a defined quantity of liquid. Connected to the second means for storage, one direction called the inlet direction, connected to the outlet direction of the first valve, one direction connected to the transport pipe, one direction sealed, one direction Is a third valve with two inlet directions, One is connected to the reagent supply pipe, the other is connected to the outlet direction of the third valve, which is connected to the diluent supply pipe, one direction is connected to the second pump, one direction is the obtained solution Is connected to a pipe that sends the
They are connected in the following way: In the first position of the second valve, the second storage means is connected on the one hand in the direction of the inlet of the second valve, on the other hand to the transport pipe and the outlet of the third valve. The direction is connected to the sealed direction of the second valve, the second pump is connected to a pipe that delivers the resulting solution to the measuring device, and in the second position of the second valve, the second The storage means
On the one hand it is connected to the second pump, on the other hand it is connected to the outlet direction of the third valve, the inlet direction of the second valve is connected to the transport pipe, and the sealed direction of the second valve is Connected to the pipe that sends the solution obtained to the measuring device,
And a fluid module characterized in that it is performed in a manner.

The storage means of each member can be constituted by a loop, and the pump can be a syringe type.

The substance whose concentration is to be determined can be, for example, a compound or a simple substance or element.

The present invention will be described in more detail below with reference to the accompanying drawings with reference to specific examples of automatic analysis of hydrazine in a solution used in a nuclear fuel reprocessing process, but the invention is not limited thereto. is not.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT The device shown in FIGS. 1 to 5 has a first mechanism 10, which is constituted by a two-position eight-way valve 11, a syringe 12 and a loop 13 made of tubing. , Can contain a fixed amount of liquid. The device also has a second mechanism 20, which is composed of a two-position eight-way valve 21, a syringe 22, a loop 23 (formed in the same manner as loop 13), and a valve 24.

For example, valves 11 and 21 have eight directions numbered 1-8. The first position can simultaneously connect direction 2 to direction 3, direction 4 to direction 5, direction 6 to direction 7 and direction 8 to direction 1 for each valve. In the second position, for each valve direction 1 to direction 2,
Direction 3 to Direction 4, Direction 5 to Direction 6, Direction 7 to Direction 8
Can be connected to at the same time.

For each valve 11 and 21, direction 1 is sealed, loop 13 or 23 is connected between directions 4 and 7, and syringe 12 or 22 is connected in direction 3.

A pipe 30 for circulating the solution to be analyzed is
Valve 11 by means of a branch circuit constituted by a pipe 14 for supplying the sampled solution and a return pipe 15
It is connected to the.

Pipe 17 connects the direction 8 of valve 11 to a tank 18 containing a suitable diluent such as nitric acid. The pipe 19 connects the direction 2 of the valve 11 to the direction 5 of the valve 21.

With respect to valve 21, transport pipe 25 connects direction 6 to pipe 30 and pipe 26 direction 8 valve 24.
, The pipe 27 connects the direction 2 to the hydrazone absorbance measuring device 31, and the pipe 32 can discharge the analyzed liquid.

The valve 24 has a first inlet direction connected by a pipe 28 to a tank 33 containing a suitable diluent such as nitric acid. The second inlet direction of the valve 24 is DMAB
It is connected by a pipe 29 to a tank 34 containing

For example, the capacities of the loops 13 and 23 are 0.
It can be 1 ml and the volume of syringes 12 and 22 can be 10 ml.

The method of operating the device will now be described with reference to FIGS. At the start of the analysis, valves 11 and 21 are shown in FIG.
To the positions shown in, that is, their first position. The syringes 12 and 22 are empty, and their pistons are pushed deeply. A pump 16 circulates the fluid to be analyzed through the loop 13. When the contents of loop 13 are considered to be representative of the solution to be analyzed, the pump is stopped and valve 11 is moved to the second position, as shown in FIG. Next, the syringe 12 is operated. As a result, the one in the loop 13 is pulled out, and at the same time, the diluent contained in the tank 18 is sucked up. When the syringe 12 is filled, the aspirated solution is
-) Experience has shown that it is homogenous.
The limited amplitude reciprocating movement of the piston of the syringe 12 allows the aspirated solution to be completely homogenous.

Return valve 11 to its first position, as shown in FIG. Syringe 12 extrudes its contents through valve 5 in direction 5 into loop 23, and through valve 6 in direction 6 into pipe 30 said first diluted solution, all except the one contained in loop 23. return.

The valve 21 is then moved to its second position, as shown in FIG. Next, the syringe 22 is started. As a result, the inside of the loop 23 is emptied, and at the same time, the tank 3
Aspirate the reagent DMAB contained in 4. Valve 24
Then, the diluent contained in the tank 33 is sucked up. With a small amplitude reciprocating motion,
The homogeneity or homogeneity of the drawn mixture is obtained as described above.

The valve 21 is then returned to its first position, as shown in FIG. The syringe 22 then expels its contents through the cell of the measuring device 31. Syringe 2
It will be done instantly after the second move.

Next, the calibration process of the automatic analyzer will be described. Taking the Lambert-Beer law into account for the measuring range, the calibration is carried out in two stages: the blank.
Perform the measurement of reagents and standard solutions.

Valve 2 for calibration based on blank reagent
1 in its second position and pure diluent introduced into loop 23. The syringe 22 sucks up the reagent contained in the tank 34 and then the diluent contained in the tank 33, and the selection is made by the valve 24. Next valve 21
Back to its first position and syringe 22 delivers the blank reagent into the photometer cell. A spectrophotometric signal is obtained.

Calibration can be continued using standard solutions instead of samples. However, it is also possible to consider a fully automated calibration programmed at regular intervals. FIG. 6 illustrates this solution. A valve 40 is added to the fluid module previously described, which allows the pump 16 to deliver the solution to be analyzed in the pipe 30 or the contents of the tank 41 by the pipe 42. This allows the loop 13 to be filled with a standard solution of the same concentration as the solution to be analyzed, which standard solution is stored in the tank 41.
To meet. The advantage is that all measuring lines can be completely tested.

The sample concentration results are given by the following relationship:

[0032]

[Equation 2]

In the formula, C _x represents the sample concentration, I _B represents the photometer untreated signal of the blank reagent, I _E represents the photometer untreated signal of the standard solution, and I _x represents the photometer untreated signal of the sample. , C
_Et represents the concentration of the standard solution.

Thus, according to the present invention, an automatic hydrazine analyzer having a fluid module can be obtained, most of which can be placed in a glove box, but for photometers, instruments. The control module and printer for collecting results can be located outside the box. The connection to the photometer can be made by optical fiber. The latter sends a light signal through the glove box so that the complete photometer assembly can be placed outside the box.

The control module is a GES associated with a Motorola microprocessor 68000 peripheral.
The PACK card controls all devices. The input / output card can be of a commercially available nature. Convert analog / digital conversion card to SPRA /
It can be of GSIA design.

The limit position of the syringe can be detected by switching. The dilution valve limit position can be determined by measuring the fluid flowing through the valve drive motor. A sudden increase in flow is interpreted as mechanical damage,
Stop the motor supply.

The results can be edited on a printer and sent to a computer.

The device equipped with the fluid module according to the invention was tested and the following results were obtained: -Analysis time: 2 minutes-Accuracy: 1-2 in the hydrazine range 0.1-0.3M.
%, The sample volume effectively sampled into the pipe: 1 μl for each analysis, the analytical effluent volume for each analysis: 1 μl of the sampling volume diluted in 10 ml of diluent.

[Brief description of drawings]

1 is a diagram of a fluid module in one operating stage of an automatic analyzer according to the invention, FIG.

FIG. 2 is a diagram of a fluid module of the automatic analyzer according to the invention in another stage of operation.

FIG. 3 is a diagram of a fluid module in a further stage of operation of the automatic analyzer according to the invention.

FIG. 4 is a diagram of a fluid module of the automatic analyzer according to the invention in a further stage of operation.

FIG. 5 is a diagram of a fluid module of the automatic analyzer according to the invention in a further stage of operation.

FIG. 6—Refilled valve to calibrate the automated analyzer,
FIG. 6 is a view of a fluid module similar to the previous drawing.

[Explanation of symbols]

 10 First Mechanism 11 Two-Position Eight-way Valve 12 Syringe 13 Loop 14 Sampling Solution Supply Pipe 15 Return Pipe 18 Diluent Tank 20 Second Mechanism 21 Two-Position Eight-way Valve 22 Syringe 23 Loop 24 Valve 30 Analytical Solution Circulation Pipe 31 Measuring device 33 Diluent tank 34 Reagent tank 40 Valve 41 Standard solution tank

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Bernard Duroll, Paris, France, Lour de la Pump, 126 (72) Inventor Pierre Brunet, France, Fontenay-O-Rosé, Lour de Moulin Aven, 7 (72) Invention Eve Charle Bourg-la-la-rain, France, Lupier-Roti, 26 (72) Inventor Michel Kwang-Queen Montigny-le-Brutnow, France, Abnew Joseph Kessel, 12

Claims (6)

[Claims] 1. A fluidic module for an automatic analyzer that allows determining the concentration of a substance in a solution, means for sampling a portion of the solution, contacting the sampled sample solution with a reagent. A means for reacting a substance contained in the sample solution with the reagent, a sample solution portion reacted with the reagent, and measuring the absorbance of a product obtained during the reaction, in the solution A fluid module comprising means for delivering to said device (31) for estimating the concentration of said substance of said fluid module, said fluid module sampling a fixed amount of the solution to said fixed amount. A first mechanism (10) for obtaining a first diluted solution of said solution, said fluid module sampling a portion of the solution diluted by said first mechanism, What A second mechanism (which makes it possible to add a defined amount of reagent and a defined amount of diluent to obtain a second diluted solution and then supply the obtained solution to the measuring device (31) ( 20) also comprises: -the first mechanism (10) comprises a first two-position eight-way valve (11), two directions of which are the first pipe (14) and the first pipe (14) of the solution sampling circuit; It is connected to a second pipe (15), two directions are connected to a first means (13) for storing a fixed amount of liquid and one direction is a pipe (for supplying diluent). 17), one direction is connected to the first pump (12), one direction called the outlet direction is connected to the second mechanism (20), one direction is sealed and those connections are Method: ★ In the first position of the first valve (11), the first storage means (1
3) is connected to the sampling circuit, the diluent supply pipe (17) is connected in the sealed direction, the outlet direction is connected to the first pump, * in the second position of the first valve, The first storage means (1
3) is connected on the one hand to the first pump (12) and on the other hand to the diluent supply pipe (17), the pipes (14, 15) of the sampling circuit being directly connected to one another, the outlet direction being Done in a manner connected in the sealed direction, the second mechanism (20) comprises a second two-position eight-way valve (21), the two directions of which are fixed. Connected to a second means (23) for storing a quantity of liquid, one direction called the inlet direction is connected to the outlet direction of the first valve (11) and one direction to the transport pipe (25). Connected, one direction is sealed, one direction is a third valve (24) with two inlet directions, one of which inlet direction is connected to the reagent supply pipe (29) and the other one is diluent supply Connected to the outlet of the third valve connected to the pipe (28), One direction is connected to the second pump (22), one said measuring device direction was obtained solution of (31)
Are connected to the pipes (27) which feed to the following ways: * In the first position of said second valve (21), the second storage means (23) is on the one hand the second valve (21). On the other hand, connected on the other hand to the transport pipe (25), the outlet direction of said third valve (24) connected to the sealed direction of said second valve, said second pump was obtained In the second position of the second valve (21), the second storage means is connected to the second pump (22) on the one hand and to the second pump (22) on the other hand. The outlet direction of the third valve (24) is connected, the inlet direction of the second valve (21) is connected to the transport pipe (25), and the sealed direction of the second valve (21) is obtained. Done in a manner connected to a pipe (27) which delivers the solution to the measuring device (31) A fluid module characterized by the above. 2. A fluid module according to claim 1, wherein each of the storage means (13, 23) is in the form of a loop. 3. A fluid module according to claim 1, wherein each pump (12, 22) is constituted by a syringe-type device. 4. A valve according to claim 1, wherein a valve (40) is provided in the solution sampling circuit to allow sampling of either the solution to be analyzed or the standard solution. The fluid module described. 5. A fluid module according to claim 1 for determining the concentration of hydrazine in a solution, wherein the reagent is dimethylaminobenzaldehyde (DMAB) and the resulting product is hydrazone. Apply. 6. Application of the fluid module according to claim 5, wherein the solution containing the hydrazine to be analyzed is used in a nuclear fuel reprocessing process.