JP2009288228A - Method and device for automatic analysis quantitative observation - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a device for automatic analysis quantitative observation for automatically observing water quality for a long period at every prescribed time safely and accurately without manpower. <P>SOLUTION: In a continuous flow analysis method, a sampled specimen S is continuously injected into a pipe 10 with reagents B and C and is quantitatively mixed with them while being segmented by air A, the mixture is decomposed by a reaction manifold 4 and then analyzed in a usual method by a detector 5. This device 1 for automatic analysis quantitative observation of all nitrogen and all phosphorus samples the specimen S every certain time and supplies it to the pipe 10, decomposes the mixture in the reaction manifold 4 by stopping it for 10 to 30 minutes and heating it while performing UV irradiation at a temperature of 80°C to 90°C, sequentially analyzes the mixtures repeatedly prepared for every certain time, and quantitatively observes all nitrogen and all phosphorus at a specimen sampling point. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an automatic analysis / quantitative observation apparatus that automatically observes the concentration measurement of ultra-trace concentration components in a test object over a long period of time using a continuous flow analysis method (CFA).

  Conventionally, as an analyzer for measuring the concentration of total nitrogen and total phosphorus contained in inspection objects such as seawater and wastewater, an analyzer using a principle called a continuous flow analysis method has been used.

In this analyzer, a reagent is continuously introduced into a tube at a constant flow rate, and a gas such as air or an inert gas is regularly injected therein to segment bubbles of the liquid, and then a sample and a necessary reagent are sequentially injected. In addition, a method is employed in which a reaction is performed using a mixing coil, a reaction coil, or the like, and the resulting reaction product is measured with a detector such as a spectrophotometer equipped with a flow cell (see, for example, Patent Documents 1 to 3). .
JP-A-8-285835 JP 2006-234601 A JP 2006-208344 A

  By the way, such an analyzer is used when managing water quality such as seawater and wastewater. In this case, from the viewpoint of water quality management, it is preferable to automatically observe the water quality over a long period of time at regular intervals without human intervention.

  However, in the case of the above-described conventional analyzer, when a reaction is performed using a reaction coil, the coil is heated at a high temperature and a high pressure, and therefore a person must be arranged in case of an emergency. Therefore, unattended automatic observation cannot be realized.

  For this reason, it is conceivable that a long reaction coil is used for reaction over a long period of time, and that the heating and pressurization conditions are relaxed to such an extent that unattended automatic observation is possible. It will be a reasonable length.

  The present invention has been made in view of such circumstances, and provides an automatic analysis and quantitative observation apparatus capable of observing water quality automatically over a long period of time at a constant time, safely and accurately without human intervention. The purpose is to do.

  In order to solve the above-described problems, the automatic analysis and quantitative observation method of the present invention is a method in which a sampled sample is continuously injected into a tube together with a reagent while being segmented by a gas, and quantitatively mixed. In the continuous flow analysis method in which analysis is performed by a conventional method using a detector, the sample is sampled at regular intervals and supplied to the tube, and the reaction manifold is stopped for 10 to 30 minutes. The mixture is decomposed by heating with UV irradiation at a temperature of 80 to 90 ° C., and the prepared mixture is repeatedly analyzed at regular intervals to sequentially analyze the total nitrogen and total at the sample sampling point. Phosphorus is quantitatively observed over time.

  In addition, the automatic analysis and quantitative observation device of the present invention for solving the above-mentioned problem is a method in which a sample sampled by an autosampler is continuously injected into a tube together with a reagent while being segmented by a gas by a weighing pump, The analyzer is mixed and decomposed by the reaction manifold, and then analyzed by a conventional method using a detector. The reaction manifold stops the mixture for 10 to 30 minutes, and is 80 to 90 ° C. The autosampler is configured to repeatedly sample the sample at intervals longer than the heating time in the reaction manifold, and is placed in the tube except during sample injection. It is designed to supply water.

  As described above, according to the present invention, the mixed solution can be decomposed without increasing the temperature and pressure by stopping the mixed solution at the reaction manifold and performing UV irradiation while heating at a temperature of 80 to 90 ° C. . Therefore, even if it is a trace amount component in a sample, it becomes possible to measure total nitrogen and total phosphorus accurately. In addition, since the mixed solution is decomposed without increasing the temperature and pressure, unattended operation is possible, and the mixed solution prepared repeatedly at regular intervals is analyzed sequentially to determine the total nitrogen and total phosphorus at the sample sampling point. Quantitative observation can be performed safely over time.

  Further, in the automatic analysis and quantitative observation apparatus of the present invention, the reaction manifold is decomposed while performing UV irradiation in addition to stopping the decomposition solution for 10 to 30 minutes and heating the decomposition solution at a temperature of 80 to 90 ° C. Therefore, an effect excellent in the decomposition performance of the mixed solution is exhibited.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 shows an outline of the overall configuration of the automatic analysis / quantitative observation apparatus 1, and FIG. 2 shows a reaction manifold 4 of the automatic analysis / quantitative observation apparatus 1.

  That is, the automatic analysis and quantification observation apparatus 1 quantifies the sample S sampled by the autosampler 2 by continuously injecting it into the tube 10 together with the reagents B and C while being segmented by the air A by the weighing pump 3. After mixing and decomposing the mixed solution in the reaction manifold 4, the analyzer is configured to analyze the detector 5 by a conventional method. The reaction manifold 4 stops the mixed solution for 10 to 30 minutes, The sampler 2 is configured to be heated while being irradiated with UV at a temperature of 80 to 90 ° C., and the autosampler 2 is configured to repeatedly sample the sample S at intervals longer than the heating time in the reaction manifold 4. Except for the time of sample injection, pure water W is supplied into the tube 10.

  The autosampler 2 is configured such that the sample suction pump is turned on and the sample solenoid valve is opened at the same time, and the sample is sucked from the sample collecting part that is constantly overflowing. Sampling is performed for about 5 to 10 minutes, and then the solenoid valve is closed and switched to suck pure water W.

  The weighing pump 3 uses a peristaltic pump to which a quantitative pump tube can be attached so that the sampled sample S and the reagents B and C can be continuously supplied into the tube 10 at a constant flow rate. . The weighing pump 3 is provided with an injection gas control line 11 capable of regularly injecting the air A in synchronism with the pulsation of the pump, and mixing the sample S introduced into the pipe 10 with the reagents B and C. The liquid can be segmented into bubbles. The mixed solution of the sample S and the reagents B and C is mixed by the vortex in each segment unit segmented by the air A. Alternatively, the tube 10 may be spirally wound and mixed by inversion mixing when passing through the inside of the spiral.

  The sample S introduced into the pipe 10 by the weighing pump 3 is first regularly segmented by air A, and alkali peroxodisulfate, which is the reagent B, is injected into each segmented unit, and the alkali decomposition is performed. It becomes the liquid mixture for. Further, in the middle position of the reaction manifold 4, sulfuric acid as another reagent C is injected to become a mixed solution for acidic decomposition with acidic potassium peroxodisulfate. In addition, as the air A to be segmented, an inert gas may be used.

  As shown in FIG. 2, the reaction manifold 4 is configured by providing a UV irradiation lamp 42 at the center of a spirally wound quartz tube 41 and covering a heater 43 from the outer periphery. Further, a branch pipe 44 for injecting sulfuric acid, which is another reagent C described above, is provided in the middle part of the quartz tube 41. The reaction manifold 4 is configured so that the quartz tube 41 can be heated at a temperature of 80 to 90 ° C. for 10 to 30 minutes while performing UV irradiation. And it controls so that the liquid mixture in the quartz tube 41 does not move over 10-30 minutes to heat. When this stop time is less than 10 minutes, the mixed solution cannot be sufficiently decomposed. Also, if it stops for more than 30 minutes, it will not be very meaningful because it is already fully decomposed. Moreover, about heating temperature, when it is less than 80 degreeC, it cannot fully decompose | disassemble. In addition, the upper limit of the heating temperature decomposes as long as it is particularly high, but if it is set high, unmanned operation is not possible in terms of safety and the like, so it is preferable to keep it within a range of 90 ° C. In addition to stopping and heating the liquid, the reaction manifold 4 irradiates the mixed liquid in the quartz tube 41 with the UV irradiation lamp 42, so that decomposition is promoted. Therefore, the mixed solution in the quartz tube 41 can be prepared as a decomposition solution effective for later analysis by heating at a low temperature of 80 to 90 ° C. for 10 to 30 minutes. At this time, the downstream side of the branch pipe 44 is a mixed solution for acid decomposition, and the upstream side is a mixed solution for alkaline decomposition. And prepared as an acid decomposition solution and an alkali decomposition solution.

  As the quartz tube 41 used for the reaction manifold 4, one having an inner diameter of 1 mm to 5 mm, more preferably 2 mm to 3 mm is used. If it is less than 1 mm, liquids such as sample S and reagents B and C passing through the quartz tube 41 are likely to be clogged, and if it exceeds 5 mm, the amount of reagents B and C used is increased and wasted. The length of the quartz tube 41 is 50 cm to 10 m, more preferably 1 m to 3 m. If it is less than 50 cm, it is impossible to prepare a sufficient amount of decomposition solution necessary for analysis. On the other hand, if the length exceeds 10 m, the amount of the decomposition solution required for the analysis will be prepared, resulting in increased waste.

  In the detector 5, first, the decomposition solution oxidized to nitrate nitrogen decomposed in the reaction manifold 4 and the decomposition solution oxidized to normal phosphoric acid are divided into two by a splitter and separately resampled. And introduced into the total nitrogen analysis system 6 and the total phosphorus analysis system 7, respectively.

  In the total nitrogen analysis system 6, the imidazole D injected into the tube 10 is segmented by air A, the decomposition solution R1 is injected there, and the cadmium-copper reduction coil 61 is passed through to convert nitrate nitrogen into nitrite nitrogen. Reduce. Next, naphthylethylenediamine E is injected, and the colored red pigment is introduced into the flow cell 51 of the spectrophotometer 50, and colorimetrically determined with a spectrophotometer near 550 nm.

  The total nitrogen analysis system 6 shows an example of analysis by ethylenediamine absorption photometry using a cadmium-copper gap coil, but is not limited thereto, and pure water or sulfuric acid solution injected into the tube 10 May be segmented with air A, and the decomposition solution R1 may be injected into the air cell A, then introduced into the flow cell 51 and colorimetrically determined with a spectrophotometer near 220 nm.

  In total phosphorus analysis system 7, molybdate coloring reagent F injected into tube 10 is segmented with gas A, and ascorbic acid reagent G and decomposition solution R2 are injected into it, and the colored blue dye of molybdenum blue is spectroscopically analyzed. The sample is introduced into the flow cell 52 of the photometer 50 and colorimetrically determined with a spectrophotometer near 880 nm.

  The spectrophotometer 50 is used as the detection device used for the detector 5, but is not particularly limited to the spectrophotometer 50, and depending on the sample S, an ultraviolet absorptiometer, a fluorometer, a flame A photometer may be used.

  The concentration of each sample S is calculated by automatically processing the signal from the detector 5 with a computer.

  The measurement of the concentration of the sample S by the automatic analysis / quantitative observation apparatus 1 is set in advance in a computer, and thereafter, it can be automatically repeated and measured over time over a long period of time. As the continuous measurement period, it is possible to perform continuous operation for one week or more throughout the year.

  The interval time for sampling the sample S is not particularly limited as long as it is longer than the stop time (10 to 30 minutes) in the reaction manifold 4. For example, every 30 minutes, every hour, or more The desired interval can be set. However, since the liquid flow in the apparatus path is stopped by stopping the liquid in the reaction manifold 4, when the interval time is set to be short, the next sample is detected after the previous sample S is detected by the detector 5. It is necessary to adjust the interval time or adjust the length of the pipe 10 in the path so that S stops at the reaction manifold S. In addition, when the interval time is long, the time during which a lot of water other than the sample S flows unnecessarily in the apparatus path increases. In this case, the next interval is detected after the previous sample S is detected by the detector 5. It is preferable to stop the entire flow of the apparatus path until the time.

  In addition, the base measurement when the pure water W is prepared only with the reagent R and the measurement of the calibration curve with the standard solution are performed every predetermined period set as data for calculating the concentration of the sample S. These base measurement and calibration curve measurement may be performed at the time of maintenance of the apparatus. When unattended operation is performed for a long period of time, the base measurement or standard solution is automatically performed during sampling of the sample S. It may be programmed to perform the calibration curve measurement.

  Further, since the sampled sample S is stopped at the position of the reaction manifold 4 to perform the decomposition process, the sample S is sent so that at least the inside of the reaction manifold 4 is filled with the sample S. This can be achieved by adjusting the feed rate of the sample S by the weighing pump 3 based on the capacity of the reaction manifold 4 and the capacity calculated from the length of the tube 10 to the reaction manifold 4. In addition, the sample water other than the sample S to be decomposed by the reaction manifold 4 is switched to the pure water W so that the excess sample S does not flow in the path of the automatic analysis and quantitative observation apparatus 1. By flowing the pure water W, the path for each measurement is cleaned each time.

Example 1
A quartz tube having an inner diameter of 2 mm and a length of 4 m is wound in a coil shape, a UV lamp is disposed so as to penetrate the center, and a band heater is wound around the quartz coil so that it can be heated to 40 to 100 ° C. An automatic analysis and quantitative observation apparatus having a reaction manifold was prepared.

  A reagent prepared by dissolving 40 g of potassium peroxodisulfate and 4 g of sodium hydroxide in 1000 ml of pure water was prepared as a reagent, and another reagent prepared by dissolving 100 ml of sulfuric acid in 1000 ml of pure water was prepared.

  A sample prepared by dissolving 0.5 g of tripolyphosphoric acid in pure water to 1000 ml was prepared.

  As shown in Table 1, when the liquid was not stopped under the conditions of no heating at the reaction manifold, heating at 70 ° C., and heating at 80 ° C., and when stopped at a stopping time of 5 to 30 minutes, The concentration of the acid aqueous solution was measured. The results are shown in Table 1.

  From Table 1, it was confirmed that the higher the heating temperature and the longer the stop time, the better the recovery rate, and in particular, when the heating temperature was stopped at 80 ° C. for 10 minutes or more, an excellent recovery rate exceeding 86% was obtained. .

Example 2
Each compound shown in Table 2 was prepared as a sample and analyzed using the same reagents and reaction manifold as in Example 1 above. The reaction manifold was stopped for 20 minutes and the experiment was conducted under the condition of heating at 80 ° C. The results are shown in Table 2.

  From Table 2, it was confirmed that an excellent recovery rate was obtained with any compound.

  The present invention is used for water quality management in water and sewage systems, seawater, rivers, lakes, and the like.

It is a circuit diagram which shows the outline of the whole structure of the automatic analysis quantitative observation apparatus based on this invention. It is an enlarged view of the reaction manifold part of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Automatic analysis quantitative observation apparatus 10 Tube 2 Autosampler 3 Weighing pump 4 Reaction manifold 5 Detector S Sample A Air (gas)
B Reagent C Reagent D Reagent E Reagent F Reagent G Reagent

Claims (2)

The sampled sample was continuously injected into the tube together with the reagent while being segmented by gas, and quantified and mixed. After this mixture was decomposed by the reaction manifold, it was analyzed by a conventional method with a detector. In the continuous flow analysis method,
Samples are sampled at regular intervals and supplied to the tube.
In the reaction manifold, the mixed solution is stopped for 10 to 30 minutes, and the mixed solution is decomposed by heating while performing UV irradiation at a temperature of 80 to 90 ° C.
The total mixture of nitrogen and total phosphorus is characterized in that it is designed to sequentially measure the total nitrogen and total phosphorus at the sample sampling point over time by sequentially analyzing the mixture prepared repeatedly at regular intervals. Automatic analysis and quantitative observation method. The sample sampled by the autosampler is continuously injected into the tube together with the reagent while being segmented by a gas with a weighing pump, and the sample is quantified and mixed. An analysis device adapted to analyze according to
The reaction manifold is configured to stop the mixture for 10 to 30 minutes and heat while performing UV irradiation at a temperature of 80 to 90 ° C.
The autosampler is designed to repeatedly sample the sample at intervals longer than the heating time in this reaction manifold,
An automatic analysis and quantitative observation device for total nitrogen and total phosphorus, characterized in that water is supplied into the tube except during sample injection.

Images