JP2007263814A - Combustion type water quality measuring instrument - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a combustion type water quality analyzer which prevents not only the scattering of sample water to the internal wall surface of a combustion part when sample water is introduced into the combustion part but also the imperfect combustion of a target component caused by the local sudden temperature fall in the combustion part. <P>SOLUTION: The combustion type water quality analyzer is configured in such a way that it includes the combustion part 10, which has a catalyst protecting material filling bed 18 and a catalyst filling bed 16 provided therein in this order and combusts sample water therein, and a sample water introducing nozzle 30 and constituted so as not only to introduce the sample water into the combustion part from the leading end of the sample water introducing nozzle but also to measure the component in the gas obtained by combusting the sample water. In the analyzer, the leading end of the sample water introducing nozzle is brought into contact with the catalyst protecting material filling bed. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a combustion-type water quality analyzer that measures components in a gas obtained by burning sample water in a combustion section.

  Conventionally, a combustion section for burning sample water inside and a dropping nozzle for sample water are provided, and a droplet of sample water is dropped into the combustion section from the dropping nozzle, and the dropped droplet is burned in the combustion section. Combustion-type water quality analyzers that measure the components in the gas obtained by the above process are known. Examples of such combustion-type water quality analyzers include, for example, a total organic carbon measuring device (TOC meter) that measures the amount of organic matter contained in sample water in order to measure the pollution of drainage and rivers, and nitrogen for the same purpose. There is a total nitrogen measuring device that measures the amount, or a device that combines these devices (for example, see Patent Document 1).

  In this case, the structure shown in FIG. 3 is conventionally used as the combustion section and the dropping nozzle of the combustion-type water quality analyzer. In FIG. 3, 10 is a combustion part, 12 shows a dripping nozzle. In the combustion unit 10, a catalyst packed layer 16 filled with a catalyst is disposed inside a combustion tube 14 made of quartz glass or the like, and a catalyst protective material packed layer 18 filled with a catalyst protective material is disposed above the catalyst packed layer 16. In addition, a heating unit 20 for heating the inside of the combustion tube 14 is provided around the combustion tube 14. In this case, an oxidation catalyst such as a platinum catalyst is used as the catalyst, and ceramic beads, quartz wool, or the like is used as the catalyst protection material. Moreover, the heating part 20 is comprised with a heater and a heat insulating material.

  When water quality analysis is performed using the combustion-type water quality analyzer of the present example, the inside of the combustion pipe 14 is heated by the heating unit 20 and a carrier gas is flowed into the combustion pipe 14 from above, and the sample is dropped by the dropping nozzle 12. A water droplet 22 is dropped into the combustion tube 14 from above. In addition, sample water is measured with a slide valve or a syringe pump, for example, and is dripped from the dripping nozzle 12 with a pump or air. The droplets 22 are heated and vaporized in the combustion tube 14, and predetermined components in the vaporized gas are oxidized by the action of the catalyst in the catalyst packed bed 16. The gas component is introduced into the detector 24 by the carrier gas, and the component in the gas is measured.

In the combustion type water quality analyzer described above, the sample water is burned at a high temperature, a predetermined component in the combustion gas is measured with a detector such as a non-dispersive infrared analyzer (NDIR), and the concentration of the measurement object is converted. Is going. For example, in a TOC meter, droplets of sample water are dropped into the combustion section and burned, and organic substances in the sample water are oxidized and converted to carbon dioxide (CO ₂ ), and the CO ₂ concentration in the combustion gas is changed to NDIR. The organic carbon concentration in the sample water is obtained by measuring with.

JP-A-56-74634

  In the above-described combustion-type water quality analyzer, a predetermined amount of sample water is introduced into the inside of the dropping nozzle by a slide valve, a syringe pump or the like after pretreatment such as dilution, and pumped by a pump or air to be catalyst from above the combustion section It is dripped on the protective material packed layer. However, at this time, sample water may be scattered on the inner wall of the combustion section due to fluctuations in pump pressure, air flow rate, nozzle orientation, sample water volume, etc., which may affect measurement accuracy. there were.

  In addition, the inside of the combustion section is usually heated to about 600 to 950 ° C., but when the amount of sample water dripped is large, when the sample water is dripped, the dripping point (the sample water droplet in the combustion section hits). In some cases, the target component in the sample water does not completely burn.

  Although the present invention has been made in view of the above-described circumstances, when sample water is introduced into the combustion part, the sample water does not scatter on the inner wall surface of the combustion part, and a local rapid temperature in the combustion part. An object of the present invention is to provide a combustion-type water quality analyzer that can prevent incomplete combustion of a target component caused by a decrease.

  In order to achieve the above-mentioned object, the present invention comprises a catalyst protection material packed layer inside and a catalyst packed layer below it, a combustion section for burning sample water inside, and a sample water introduction nozzle, A combustion-type water quality analyzer that introduces sample water into a combustion part from the tip of a water introduction nozzle and measures a component in a gas obtained by burning the sample water in the combustion part, the tip of the sample water introduction nozzle A combustion-type water quality measuring apparatus is provided in which the catalyst protection material packed layer is brought into contact with the catalyst protection material packed bed.

  In the combustion-type water quality analyzer of the present invention, the tip of the sample water introduction nozzle is brought into contact with the catalyst protective material packed bed, so that the sample water is directly introduced into the catalyst protective material packed bed. Therefore, the sample water does not scatter on the inner wall surface of the combustion unit, and high-precision measurement can be performed. In the combustion-type water quality analyzer of the present invention, since the tip of the sample water introduction nozzle is extended and brought into contact with the catalyst protective material packed layer, the sample water is heated in the sample water introduction nozzle and is heated to a high temperature or already vaporized. In this state, the catalyst protective material is introduced into the packed bed. Therefore, the local rapid temperature drop does not occur at the location where the sample water flows out from the sample water introduction nozzle in the combustion section, and as a result, the combustion efficiency of the sample water in the combustion section is improved and incomplete combustion of the target component occurs. Is prevented.

  In the present invention, it is preferable to extend the tip of the sample water introduction nozzle to the inside of the catalyst protective material packed layer. As a result, it is possible to more reliably prevent the sample water from splashing on the inner wall surface of the combustion section, and also to heat the sample water to a higher temperature in the sample water introduction nozzle, so that the sample in the combustion section can be heated. Water combustion efficiency can be further improved.

  In the present invention, the sample water introduction nozzle can be formed of quartz glass, metal or the like, but is preferably formed of metal in terms of excellent heat conductivity. Accordingly, the sample water can be heated to a higher temperature in the sample water introduction nozzle, and the combustion efficiency of the sample water in the combustion section can be further improved.

  The combustion-type water quality analyzer of the present invention is a target component that is generated when a sample water is not scattered on the inner wall surface of the combustion part when the sample water is introduced into the combustion part, and is caused by a local rapid temperature drop in the combustion part. Can prevent incomplete combustion. Therefore, according to the combustion-type water quality analyzer of the present invention, it is possible to perform highly accurate water quality analysis.

  Hereinafter, an example of the best mode for carrying out the present invention will be described with reference to the drawings. FIG. 1 is a schematic view showing an example of a combustion part and a sample water introduction nozzle of a combustion-type water quality analyzer according to the present invention. In FIG. 1, 30 is a sample water introduction nozzle, 12 is a combustion part. The combustion unit 10 is the same as that shown in FIG. That is, the catalyst protection material packed layer 18 and the catalyst packed layer 16 below the catalyst protective material packed layer 18 are provided inside the combustion tube 14, and the heating unit 20 is provided around the combustion tube 14. The combustion unit 10 is connected to the detector 24.

  The sample water introduction nozzle 30 is made of stainless steel, and the tip thereof extends to the inside of the catalyst protective material packed layer 18. However, the material of the sample water introduction nozzle 30 is not limited, and a metal having heat resistance and oxidation resistance, an alloy, quartz glass, or the like can be used as appropriate. A predetermined amount of sample water is introduced into the sample water introduction nozzle 30 by a slide valve or syringe pump after pretreatment such as dilution, and is pumped by a pump or air and filled with a catalyst protective material from the tip of the sample water introduction nozzle 30. Introduced into layer 18. In this case, since the sample water introduction nozzle 30 extends to the inside of the catalyst protective material packed bed 18, the sample water does not scatter on the inner wall surface of the combustion tube 14, and the sample water is made of metal sample water. Since it is heated in the introduction nozzle 30, it is introduced into the catalyst protective material packed layer 18 in a vaporized state. In addition, the water quality analysis method by the combustion type water quality analyzer of this example is the same as that of the combustion type water quality analyzer of FIG.

  The combustion unit and the sample water introduction nozzle of the above-described embodiment can be used for the combustion unit and the sample water introduction unit of the total organic carbon measuring device configured as shown in FIG. 2, for example. In FIG. 2, 100 is a sample water tank, 102 is a dilution water tank, 104 is an IC removal liquid tank, 106 is a dilution tank, 108 is a sample water introduction part, 110 is a combustion part, 112 is a carrier gas supply means, 114 is a dehumidifier, Reference numeral 116 denotes a detector (NDIR).

The total organic carbon measuring apparatus of this example mixes sample water, dilution water, and an IC removal solution (hydrochloric acid, etc.) in a dilution tank 106, thereby diluting the sample water and at the same time ICs such as carbon dioxide contained in the sample water. After removing (inorganic carbon), the sample water is introduced from the sample water introduction unit 108 into the combustion unit 110 in a state where the carrier gas is supplied into the combustion unit 110 by the carrier gas supply unit 112. In the combustion unit 110, organic substances in the vaporized sample water gas are oxidized by the action of the catalyst and converted to CO ₂ . Then introduced into the detector 116 through the dehumidifier 114 of the gas, by measuring the CO ₂ concentration in the gas, and requests organic carbon concentration in the sample water. The combustion section and the sample water introduction nozzle of the above-described embodiment can be used for the combustion section 110 and the sample water introduction section 108 of the total organic carbon measurement device of this example.

It is the schematic which shows an example of the combustion part of the combustion type water quality analyzer which concerns on this invention, and a sample water introduction nozzle. It is a conceptual diagram which shows an example of a total organic carbon measuring apparatus. It is the schematic which shows the prior art example of the combustion part of a combustion type water quality analyzer, and a sample water introduction nozzle.

Explanation of symbols

12 Combustion unit 14 Combustion tube 16 Catalyst packed layer 18 Catalyst protective material packed layer 20 Heating unit 24 Detector 30 Sample water introduction nozzle

Claims (3)

  A catalyst protection material packed layer is provided inside and a catalyst packed layer is provided therebelow, and includes a combustion section for burning sample water therein and a sample water introduction nozzle, and the sample water is introduced into the combustion section from the tip of the sample water introduction nozzle. Is a combustion-type water quality analyzer that measures the components in the gas obtained by burning the sample water in the combustion section, the tip of the sample water introduction nozzle being brought into contact with the packed layer of the catalyst protection material Combustion-type water quality measuring device characterized by that.   The combustion type water quality measuring device according to claim 1, wherein the tip of the sample water introduction nozzle extends to the inside of the catalyst protective material packed bed. The combustion type water quality measuring apparatus according to claim 1 or 2, wherein the sample water introduction nozzle is made of metal.

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