JPH04120443A - Analyzing apparatus of moisture and total organic carbon - Google Patents

Abstract

PURPOSE:To analyze moisture and organic carbon all at once by converting the moisture in a sample to acetylene, and measuring the acetylene in the same manner as the total carbon or inorganic carbon. CONSTITUTION:A sample is injected from a feed port 3. The moisture included in the sample is converted to acetylene by a calcium carbide pipe 5, and further converted along with the total carbon contained in the sample to carbon dioxide gas and water at a total carbon burning pipe 9. After the moisture is removed at 10, the concentration of the carbon dioxide gas Dt is detected at 12. Accordingly, the concentration Dt indicating the sum of the concentration of the moisture Dh and the concentration of the total carbon Dtc in the sample can be obtained. Subsequently, the sample is injected from a feed port 6, and the total carbon contained in the sample is oxidized at the total carbon burning pipe 9. The moisture is removed at 10, and the concentration of the total carbon Dtc is detected at 12. The concentration of the moisture Dh in the sample can be obtained by calculating the difference of the concentrations Dt and Dtc. Then, the sample is injected from a feed port 13. Only inorganic carbon is selectively oxidized in an inorganic carbon burning pipe 16, and the moisture is removed at 10. The concentration of the inorganic carbon Dic is detected at 12. The concentration of the organic carbon Doc in the sample can be obtained by the difference of the concentrations Dtc and Dic.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an apparatus suitable for analyzing moisture and total organic carbon contained in a gas.

(Prior technology) To analyze organic carbon and inorganic carbon dissolved in water, a device M is used in which a non-dispersive infrared gas analyzer is connected to a combustion tube that selectively burns total carbon and inorganic carbon, respectively. Currently, the carbon contained in wood is converted into carbon dioxide gas, which is then detected using a non-dispersive infrared gas analyzer.

(Problem to be solved by the invention) However, since such a device analyzes carbon contained in water, it can analyze organic carbon contained in, for example, the air of a plant cultivation environment. and moisture cannot be used for analysis.

The present invention was made in view of these problems, and its purpose is to provide a novel analysis bag M that can simultaneously analyze moisture and organic carbon contained in gases such as air. It's about doing.

(Means for Solving the Problems) In order to solve such problems, the present invention provides a calcium carbide pipe connected to a combustion auxiliary gas source from which carbon dioxide gas and moisture have been removed through a sample injection port, an all-carbon combustion tube connected to the discharge side of the tube via a sample injection port; a carbon dioxide detection means connected to the discharge side of the all-carbon combustion tube; and an inflow side connected to the auxiliary gas source via the sample injection port. Further, an inorganic carbon combustion tube connected to the carbon dioxide gas detection means on the discharge side is provided.

(Function) After the moisture contained in the gas is converted to acetylene by calcium carbide, it is converted to carbon dioxide gas by a combustion tube along with all the carbon contained in the sample, and the concentration is detected by a carbon dioxide gas detection means. Ru. Further, all the carbon contained in the gas is converted into carbon dioxide gas by the total carbon combustion tube, and the concentration is measured by the carbon dioxide gas detection means. By determining these differences, the concentration of water contained in the gas can be determined. Further, the inorganic carbon is converted into carbon dioxide gas by the inorganic carbon combustion tube, and its concentration is detected by the carbon dioxide gas detection means. Concentration and absence of total carbon! Organic carbon can be determined by calculating the difference from the concentration of IIN element.

(Example) The details of the present invention will be described below based on illustrated examples.

Figure 1 (shows one embodiment of the present invention), in which reference numeral 1 is a switching valve connected to an auxiliary combustion air source 2 from which moisture and carbon dioxide have been removed; A calcium carbide tube 5 containing calcium carbide 4 is connected through a measurement sample inlet 3. An oxidation catalyst 7 is connected to an outlet of the calcium carbonate tube 5 through a total organic carbon measurement sample inlet 6. At the same time, an all-carbon combustion tube 9 maintained at a high temperature of about 680° C. by a heater 8 is connected to the exhaust port of the all-carbon combustion tube 9.
A non-dispersive infrared gas detector 12 is connected via a filter unit 11 .

The other outlet of the switching valve 1 houses an oxidation catalyst 14 through an inorganic carbon sample inlet 13, and is heated to a relatively low temperature 150 at a temperature low enough to oxidize only inorganic carbon using a heater 15.
An inorganic carbon combustion tube 16 maintained at about 0.degree. C. is connected, and its outlet is connected to the moisture removal unit 10.

In this embodiment, when the switching valve 1 is set to the first flow path and the sample is injected from the moisture measurement sample inlet 3, the sample flows into the calcium carbonate pipe 5 together with the dry air from the auxiliary combustion air source 2. Then, 2H20+C2Ca −+ C2
It is converted to acetylene by a reaction called H2. Acetylene flows into the total carbon combustion tube 9 via the total carbon measurement sample inlet 6 and is decomposed into carbon dioxide and water through the reaction C2H2+O□ → C○2+H20, and the total carbon contained in the sample is , C, H, N, ◆002= pc○2◆Q/2 H20”
Both are converted into carbon dioxide gas and water by the reaction rN○.

The moisture is removed from these carbon dioxide gas and moisture by a moisture removal unit 1°, and the concentration of carbon dioxide gas is measured by a non-dispersive infrared gas detector 12 via a filter unit 11. Needless to say, the measured value Dt at this stage indicates the sum of the moisture concentration Dh and the total carbon concentration Ttc in the sample.

Next, when the same sample is injected through the sample inlet 6 for total carbon measurement, the auxiliary combustion air that has flowed in through the calcium carbide gastric tube 5 is carried to the total carbon combustion tube 9, and the organic matter contained in the sample is All carbon and inorganic carbon are oxidized and decomposed into carbon dioxide gas and moisture. After moisture is removed from these carbon dioxide gas and moisture by a moisture removal unit 10, all carbon is decomposed by a non-dispersive infrared gas detector 12. concentration D tc
is measured.

As a result, the concentration of water contained in the sample can be determined by calculating the difference Dt-Dte between the concentration Dt determined by the previous measurement and the concentration Dtc determined by the current measurement.

Next, when the switching valve 1 is switched to the other flow path and the same sample as the previous one is injected into the sample injection port 13 for inorganic carbon measurement,
Only the inorganic carbon contained in the sample is carried by the auxiliary combustion air to the inorganic carbon combustion tube 16 and is selectively oxidized and decomposed into carbon dioxide and moisture. After the moisture is removed by the moisture removal unit 10, non-organic carbon is removed. The inorganic carbon concentration T+, is measured by the distributed infrared gas detector 12--thus, the difference Dtc-D between the total carbon concentration Dtc and the inorganic carbon concentration DIC. By calculating the concentration of organic carbon. It is possible to find c'8.

[Example: After calibrating the same device using synthetic air with 800 PPM of carbon dioxide and 200 PPM of water added as a standard sample,
When the moisture and organic carbon contained in the air in the tomato ripening room were measured, the results agreed with a high degree of accuracy with the results measured using a regular moisture measuring device. In addition, the total organic carbon present in the ripening chamber of plants is ethylene, which is excavated during the ripening process of plants.
The concentration of ethylene was measured using a gas chromatograph, and when the results of this measurement were compared with the results of measuring the carbon concentration using the same device, they agreed with extremely high accuracy.

By the way, if you also want to analyze the hydrogen contained in the sample, inject the sample for hydrogen measurement from the switching valve 1 side into the gate of the switching valve 1 and the sample injection port 3 for moisture measurement, as shown in Figure 2. Entrance 20
, a water removal unit 21, and an oxidation furnace 22 that selectively oxidizes only hydrogen, the hydrogen measurement sample injection port 2
After moisture is removed from the sample injected into the sample by a moisture removal unit 21 using auxiliary combustion air, only hydrogen is selectively oxidized by an oxidation furnace 22 and converted into water. This moisture is converted into acetylene by the calcium carbide tube 5, and thereafter detected as carbon dioxide gas through the steps described above.

In this example, carbon dioxide gas is detected using a non-dispersive infrared gas detector, but the same effect can be obtained using other types of carbon dioxide gas detectors such as thermal conductivity type gas detectors. It is clear that it plays.

(Effects of the Invention) As explained above, in the present invention, a calcium carbide pipe is connected to a combustion auxiliary gas source from which carbon dioxide and moisture have been removed through a sample injection port, and a sample injection port is provided on the discharge side of the calcium carbide pipe. an all-carbon combustion tube connected through the tube, a carbon dioxide detection means connected to the discharge side of the all-carbon combustion tube, and an inorganic Since it is equipped with a carbon combustion tube, it is possible to convert the moisture contained in the gas into acetylene, then convert it into carbon dioxide gas using the carbon combustion tube, and then measure it using the same method as total carbon and inorganic carbon. It is possible to simultaneously analyze moisture and total organic carbon contained in a sample with high sensitivity.

[Brief explanation of drawings]

FIG. 1 is a block diagram of an apparatus showing one embodiment of the present invention, and FIG. 2 is a block diagram showing another embodiment of the present invention. 1...Switching valve 2...Combustion auxiliary gas source 3...Sample inlet for moisture measurement 5...Calcium carbide tube 6...Sample inlet for total carbon measurement 9...・All carbon combustion tube

Claims (1)

[Claims] a calcium carbide tube connected to a source of auxiliary combustion gas from which carbon dioxide and moisture have been removed through a sample inlet; an all-carbon combustion tube connected to the discharge side of the calcium carbide tube through a sample inlet; a carbon dioxide gas detection means connected to the discharge side of the pipe, and an inflow side connected to the combustion auxiliary gas source through the sample injection port;
Further, a moisture and total organic carbon analyzer comprising an inorganic carbon combustion tube whose discharge side is connected to the carbon dioxide gas detection means.