JP3762619B2 - Analyzer - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an analyzer that performs analytical measurement by introducing a sample solution into a measurement cell.
[0002]
[Prior art]
When performing analytical measurement by introducing a sample solution into a measurement cell, the measured value may be greatly affected by the temperature of the sample solution, depending on the measurement method. In particular, spectroscopic methods such as near infrared spectroscopy The effect is remarkable in.
[0003]
For example, when the sample solution to be analyzed and measured is an ammonia-hydrogen peroxide aqueous solution, a large amount of bubbles are generated at a high temperature, and measurement data is often affected by interference due to the bubbles. Therefore, in such a case, in order to perform accurate measurement, it is desirable to lower the liquid temperature and adjust the temperature.
[0004]
As a conventional analyzer in which the above points are considered, as shown in FIG. 4, a cooling unit 1 for cooling the sample liquid S, and a defoaming tank 18 for removing bubbles in the sample liquid S, Some have a measurement cell 3 for analyzing the sample liquid S and a valve 19 for temporarily stopping the flow of the sample liquid S. In the figure, 4 is a sample tank and 5 is a suction pump.
[0005]
[Problems to be solved by the invention]
However, in the conventional analyzer having the above-described configuration, the flow of the sample liquid S is stopped by the valve 19 for each measurement of the sample liquid S in the measurement cell 3, so that one analysis measurement is performed. There is a problem that the time required for the process becomes long (for example, it takes about 20 seconds at the shortest).
[0006]
Further, if bubbles generated spontaneously adhere to the measurement cell 3, the analysis of the analyzer is adversely affected, so that the bubbles need to be removed from the measurement cell 3.
[0007]
The present invention has been made in consideration of the above-described matters, and an object of the present invention is to provide an analyzer that can accurately analyze and measure a sample liquid in which bubbles are easily generated in a short time.
[0008]
[Means for Solving the Problems]
In order to achieve the above object, the present invention is an analyzer that performs analytical measurement by introducing a sample liquid into a measurement cell, and a bubble removing unit for removing bubbles in the sample liquid upstream of the measurement cell And a flow rate control means for continuously introducing the sample liquid into the measurement cell and for controlling the flow rate of the sample liquid flowing continuously through the measurement cell to the outlet path downstream of the measurement cell in at least two stages. It is possible to switch between a measurement state in which the flow rate of the sample liquid passing through the measurement cell is low and the measurement cell side is high pressure, and a bubble removal state in which the flow rate of the sample liquid passing through the measurement cell is high and the measurement cell side is low in pressure. (Claim 1).
[0009]
In the analyzer having the above-described configuration, the flow rate of the sample liquid continuously passing through the measurement cell can be adjusted in two stages: a measurement state in which the measurement cell side has a high pressure and a bubble removal state in which the measurement cell side has a low pressure. Therefore, the bubbles attached in the measurement cell can be easily removed by rapidly changing the flow rate of the sample solution flowing in the measurement cell.
[0010]
[0011]
Further, the flow rate control means may be provided also in the branch path (Claim 2 ). In this case, it is possible to easily balance the flow rate of the sample liquid flowing through the outlet path and the flow rate of the sample liquid flowing through the branch path.
[0012]
Further, the lead-out path may have a bypass flow path, and the bypass flow path may be arranged so as to straddle the flow rate control means provided in the lead-out path (Claim 3 ). In this case, the flow rate of the sample liquid flowing through the measurement cell can be adjusted to at least two stages with a simple configuration.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, details of the present invention will be described with reference to the drawings.
FIG. 1 is an explanatory diagram schematically showing the configuration of the analyzer D according to the first embodiment of the present invention.
The analyzer D of the present invention includes a bubble removing unit 2 for removing bubbles in the sample solution S on the upstream side of the measurement cell 3, and the sample solution S in a state where the bubbles are removed is continuously provided in the measurement cell 3. The sample solution S is analyzed and measured, and the flow rate of the sample solution S passing through the measurement cell 3 can be adjusted to at least two stages, and the flow rate of the sample solution S passing through the measurement cell 3 is reduced, The measurement cell 3 side is configured to be switchable between a measurement state in which the pressure is high and a bubble removal state in which the flow rate of the sample liquid S passing through the measurement cell 3 is large and the measurement cell 3 side is at a low pressure.
[0014]
The analyzer D includes a bubble removing unit 2 into which the sample liquid S sent from the external sample tank 4 through the first introduction path 6 by the suction pump 5 is introduced, and the first introduction path 6. A second introduction path 7 for introducing the cooling unit 1 for cooling the sample solution S and the sample solution S from the bubble removing unit 2 to the measurement cell 3 for performing analysis and measurement of the sample solution S is provided. A lead-out path 8 for leading (returning) the sample liquid S from the measurement cell 3 to the external sample tank 4, a check valve 9 provided in the lead-out path 8, and a sample from the bubble removing unit 2 And a branch path 10 for sending a part of the liquid S directly to the outlet path 8. A flow rate control means 11 for controlling the flow rate of the sample liquid S flowing through the lead-out path 8 and a downstream side of the check valve 9 are provided in the lead-out path 8 and straddle the flow rate control means 11. And a bypass channel 12 disposed in the center.
[0015]
The sample liquid S is, for example, an ammonia-hydrogen peroxide aqueous solution, and is held in a high temperature state in the sample tank 4. The sample solution S is not limited to an ammonia-hydrogen peroxide solution, and may be a chemical solution such as a sulfuric acid-hydrogen peroxide solution or a hydrochloric acid-hydrogen peroxide solution. That is, the analyzer D of the present invention can stably measure a sample solution S such as a multi-component aqueous solution that easily generates bubbles at high temperatures.
[0016]
The cooling unit 1 is configured by disposing an exhaust fan 1b close to a heat exchange portion 1a formed by winding a part of the first introduction path 6 in a spiral shape. The cooling unit 1 is not limited to such a configuration. For example, the heat exchange portion 1a may be provided in a linear shape or a zigzag shape, but the efficiency of heat exchange of the sample liquid S by the exhaust fan 1b is not limited. In order to improve as much as possible, it is desirable that the heat exchange portion 1a has a surface area as large as possible at a short distance. Further, the cooling unit 1 is not limited to the one in which the exhaust fan 1b is brought close to the heat exchanging portion 1a as described above, and may be, for example, a configuration that electrically cools or a configuration that cools by water cooling. It may be one having both of these configurations.
[0017]
The bubble removing unit 2 includes, for example, a defoaming tank and separates bubbles in the sample liquid S sent through the first introduction path 6. And the bubble removal part 2 sends out the gas which generate | occur | produced in the sample liquid S from the one end side (upper side) toward the derivation path 8 in the branch path 10, and bubbles from the other end side (lower side). In this configuration, the sample solution S from which the gas is separated is sent into the second introduction path 7 toward the measurement cell 3. In addition, the bubble removal part 2 is not restricted to a defoaming tank, For example, a T-shaped pipe etc. may be sufficient.
[0018]
A light source 3a that emits light of a specific wavelength and a detector 3b that can detect the light are arranged on both sides of the measurement cell 3, and the light of the specific wavelength from the light source 3a is sampled inside. By irradiating the measurement cell 3 in a state where the liquid S is flowing and detecting the light transmitted through the measurement cell 3 by the detector 3b, the absorbance can be measured with high accuracy. From this absorbance, the component concentration can be detected using a conversion formula such as Lambert-Beer's law.
[0019]
A cooling unit 13 is provided in the second introduction path 7 for cooling the sample liquid S after the bubbles are removed in the bubble removing unit 2. The cooling unit 13 has the same configuration as the cooling unit 1, and is arranged with an exhaust fan 13b in proximity to a heat exchange portion 13a formed by spirally winding a part of the second introduction path 7. It is comprised by doing. The cooling unit 13 is not limited to such a configuration. For example, the heat exchange portion 13a may be provided in a linear shape or a zigzag shape, but the heat exchange of the sample liquid S by the exhaust fan 13b is possible. In order to improve the efficiency of the heat exchange as much as possible, it is desirable that the surface area of the heat exchange portion 13a be as large as possible over a short distance. Further, as described above, the cooling unit 13 is not limited to the one in which the exhaust fan 13b is brought close to the heat exchanging portion 13a. For example, the cooling unit 13 may be one that is electrically cooled or one that is cooled by water cooling. It may be one having both of these configurations.
[0020]
The cooling unit 13 may be provided when the sample solution S is at a particularly high temperature, and need not always be provided.
[0021]
Further, both the exhaust fan 1b constituting the cooling unit 1 and the exhaust fan 13b constituting the cooling unit 13 can be permanently installed in the analyzer D, but a dedicated exhaust fan should be used. Alternatively, for example, an electronic cooler using a Peltier element or the like may be used, or a structure in which cooling is performed by water cooling may be used. Of course, it may have a plurality of the above cooling means and cooling structures.
[0022]
Furthermore, both the cooling unit 1 and the cooling unit 13 may be disposed either inside or outside the analyzer D.
[0023]
The sample liquid S from the lead-out path 8 may be sent to another sample tank or the like (not shown) without returning to the sample tank 4.
[0024]
The flow rate control means 11 is, for example, a variable needle valve, and controls the flow rate of the sample liquid S flowing through the lead-out path 8. The flow rate of the sample liquid S flowing through the outlet path 8 is reduced ( squeezed) by the flow rate control means 11 . The flow rate / flow velocity is determined in consideration of the time required for measuring the sample liquid S in the measurement cell 3. The flow rate control means 11 is not limited to the needle valve, and may be, for example, a member (for example, a fixed capillary) 14 capable of obtaining a predetermined resistance as shown in FIG. The variable valve 15 or the like that can adjust the flow rate of the sample liquid S more easily and reliably as shown in FIG. Further, the variable valve 15 may be a valve having a bypass flow rate adjusting function capable of adjusting the flow rate of the sample liquid S flowing through the bypass flow path 12.
[0025]
Further, the flow rate control means 16, which is a member having the same structure as the flow rate control means 11, is also provided in the branch path 10, whereby the flow rate of the sample liquid S flowing through the outlet path 8 and the sample liquid S flowing through the branch path 10. It is possible to easily balance the flow rate.
[0026]
One end of the bypass flow path 12 is connected to the lead-out path 8 between the check valve 9 and the flow rate control means 11 provided on the downstream side of the check valve 9, and the other end is connected to the branch passage. It is connected to the lead-out path 8 on the downstream side of the connection point between the path 10 and the lead-out path 8. The other end may be connected to the outlet path 8 on the downstream side of the flow rate control means 11 and on the upstream side of the connection point.
[0027]
The bypass channel 12 is provided with an on-off valve 17 made of, for example, a two-way solenoid valve or a two-way pneumatic valve. The on-off valve 17 allows the sample solution S to flow through the bypass channel 12, It is possible to perform an operation to prevent the flow. Note that the flow rate of the sample liquid S that can be flowed to the bypass flow path 12 is sufficiently larger than the flow rate of the sample liquid S that can be flowed to the outlet path 8 provided with the flow rate control means 11. It is comprised so that it may become.
[0028]
Next, the operation of the analyzer D having the above configuration will be described.
In order to analyze the sample liquid S previously stored in the sample tank 4 using the analyzer D, first, the sample liquid S is introduced into the analyzer D through the first introduction path 6 by the suction pump 5. To do. Then, after the sample liquid S introduced into the analyzer D is cooled in the cooling unit 1, bubbles generated in the bubble removing unit 2 are removed. The bubbles removed from the sample liquid S in the bubble removing unit 2 are sent to the outlet path 8 through the branch path 10, while the sample liquid S from which the bubbles have been removed are sent to the second introduction path 7, After being cooled in the cooling unit 13, it is sent to the measurement cell 3.
[0029]
Then, a predetermined analysis is performed in the measurement cell 3, and thereafter, the measurement cell 3 is led out of the analyzer D through the check valve 9 and the flow rate control means 11 in the lead-out path 8, and returned to the sample tank 4. . In the measurement state in which the sample solution S is analyzed as described above, the on-off valve 17 provided in the bypass channel 12 is closed, and the sample solution S does not flow through the bypass channel 12. .
[0030]
If the analysis of the sample liquid S is continued using the analyzer D as described above, bubbles generated spontaneously may adhere to the measurement cell 3 and adversely affect the measurement. In such a case, the sample liquid on the downstream side of the measurement cell 3 is opened by opening the on-off valve 17 provided in the bypass flow path 12 and removing the bubbles in which the sample liquid S also flows into the bypass flow path 12. The flow rate of S increases rapidly, and the flow rate of the sample liquid S flowing through the measurement cell 3 also increases rapidly. Then, the sample liquid S whose flow rate is rapidly increased is caused to flow through the measurement cell 3, whereby bubbles in the measurement cell 3 are removed.
[0031]
In the analyzer D having the above-described configuration, the flow rate of the sample liquid S flowing through the measurement cell 3 is at least in two stages, that is, the level that can be analyzed by the measurement cell 3 and the level that bubbles attached to the measurement cell 3 can be removed. In other words, the flow rate of the sample liquid S passing through the measurement cell 3 is small, the measurement state in which the measurement cell 3 side is at a high pressure, and the flow rate of the sample liquid S passing through the measurement cell 3 is large. Since it is possible to switch to the bubble removal state in which the side 3 is at a low pressure, the sample liquid S can be analyzed in a short time and continuously, and the bubbles adhering to the measurement cell 3 can be easily removed. It is.
[0032]
In the analyzer D shown in FIGS. 1 and 2, at least two stages of adjustment of the flow rate of the sample liquid S flowing through the measurement cell 3 are performed by opening and closing the on-off valve 17 provided in the bypass flow path 12. However, as shown in FIG. 3, in the analyzer D using the variable valve 15 capable of easily and reliably changing the flow rate of the sample solution S as the flow rate control means 11, only the variable valve 15 is adjusted. As a result, the flow rate of the sample liquid S flowing through the measurement cell 3 can be adjusted in at least two stages, so that the bypass flow path 12 and the on-off valve 17 can be omitted.
[0033]
In the analyzer D having the above-described configuration, regarding the detection of bubbles in the measurement cell 3, it is conventionally performed to determine the bubbles as software based on the measurement waveform or the like and to perform data processing. Further, in order to remove bubbles adhering in the measurement cell 3, the opening / closing of the on-off valve 17 provided in the bypass passage 12 is periodically / every time (for example, every 30 minutes, every hour, etc.). It may be performed when a bubble is detected by software processing.
[0034]
In the analyzer D having the above configuration, since the sample liquid S introduced from the outside of the analyzer D can be sent to the bubble removing unit 2 at a high speed, a delay in response is not a problem.
[0035]
Further, at the time of analysis of the sample liquid S, the flow rate of the sample liquid S flowing in the vicinity of the measurement cell 3 is reduced by the flow rate control means 11, so that the flow rate of the sample liquid S flowing in the vicinity of the measurement cell 3 becomes small. Thereby, when the cooling unit 13 is provided, the cooling efficiency of the sample solution S in the cooling unit 13 is increased, and the temperature of the sample solution S is set to a desired value by using the cooling unit 13 having a simple configuration. The temperature can be lowered. Further, in addition to the increase in cooling efficiency, the pressure of the sample liquid S on the upstream side of the flow rate control means 11 is increased, so that the generation of bubbles from the sample liquid S is suppressed, and the sample liquid S in the measurement cell 3 is suppressed. The number of times that the analysis can be performed with high accuracy, the bubbles are less likely to adhere to the measurement cell 3, and the opening / closing valve 17 of the bypass channel 12 is opened to clear the bubbles adhering to the measurement cell 3. Can be reduced.
[0036]
Note that the analyzer D having the above-described configuration has a configuration in which only the gas is led out from the bubble removing unit 2 to the branch path 10. However, the configuration is not limited to this, and the bubble removing unit 2 is not limited thereto. It is good also as a structure which derives | leads out most not only gas but the sample liquid S to the branch path 10 from. In this case, the sample liquid S can be introduced from the sample tank 4 into the analyzer D in a shorter time.
[0037]
【The invention's effect】
As described above, according to the analyzer D of the present invention, it is possible to accurately analyze and measure a sample liquid in which bubbles are easily generated in a short time.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram schematically showing a configuration of an analyzer according to a first embodiment of the present invention.
FIG. 2 is an explanatory diagram schematically showing a configuration of an analyzer when a member capable of obtaining a predetermined resistance is used as the flow rate control means in the first embodiment.
FIG. 3 is an explanatory diagram schematically showing the configuration of an analyzer when a variable valve is used as the flow rate control means in the first embodiment.
FIG. 4 is an explanatory diagram schematically showing a configuration of a conventional analyzer.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 2 ... Bubble removal part, 3 ... Measurement cell, 6 ... 1st introduction path, 7 ... 2nd introduction path, 8 ... Derivation path, 10 ... Branching path, 11, 16 ... Flow control means, 12 ... Bypass flow path, D ... Analyzer, S ... Sample solution.

Claims (3)

  An analyzer for introducing a sample liquid into a measurement cell and performing an analytical measurement, comprising an air bubble removing unit for removing bubbles in the sample liquid upstream of the measurement cell, and continuously supplying the sample liquid to the measurement cell A flow rate control means for controlling the flow rate of the sample liquid continuously flowing through the measurement cell in at least two stages in the outlet path downstream of the measurement cell, and the flow rate of the sample liquid passing through the measurement cell The analyzer can be switched between a measurement state in which the measurement cell side is at a high pressure and a bubble removal state in which the flow rate of the sample liquid passing through the measurement cell is large and the measurement cell side is at a low pressure. The analyzer according to claim 1 , wherein the flow rate control means is also provided in the branch path. The analyzer according to claim 1 or 2 , wherein the outlet passage has a bypass passage, and the bypass passage is disposed so as to straddle the flow rate control means provided in the outlet passage.

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