JPH02257061A - Measuring device for organic carbon - Google Patents

Abstract

PURPOSE:To precisely measure large amounts of a sample by furthermore continuing monitoring for a constant time without deciding a detected peak as a peak end even when the inclination of the peak detected by a gas detector is made some value or below and judging the true peak end. CONSTITUTION:A sample is introduced into a combustion furnace together with carrier gas and gasified and the whole organic carbon contained in the sample is converted into carbon dioxide. This carbon oxide is detected by a gas detector via a pretreatment part and indicated to a computer as a peak. Therein the computer undecides this peak as a peak end even when the inclination of the peak is made some value or below and furthermore continues monitoring for a constant time. The true peak end is judged by recognizing both rise of a new peak and existence of a large negative. Then the area of the peak indicated therein is calculated as the amount of the whole organic carbon. Thereby miscalculation of the area of the peak is eliminated and large amounts of the sample can be precisely measured.

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to an organic carbon measuring device for measuring the amount of total organic carbon contained in industrial wastewater, lake water, river water, seawater, etc.

[Conventional technology]

In conventional organic carbon measurement devices, sample water containing organic carbon is first converted into carbon dioxide in a combustion furnace,
Sent to gas detector. The total amount of organic carbon is detected here as the amount of carbon dioxide and appears as a peak on the display, so the total amount of organic carbon can be determined by integrating the area up to the end of this peak.

[Problems to be solved by the invention]

In order to measure accurately with the above device, it is necessary to increase the amount of sample injected into the device, but since the sample is vaporized in the combustion furnace and its volume rapidly engraves, a large amount of sample must be injected at once. If it is vaporized, it may damage the combustion furnace and be dangerous. Therefore, the temperature of the combustion furnace was set to the normal 900℃.
The sample is gradually vaporized at a low temperature of about 680° C. from the front and back, but in this case, the measurement peaks may be separated. However, with conventional devices, when the slope of the measured peak falls below a certain value, that point is detected as the end of the peak and the peak area is automatically calculated. In the case of a stepped shape, there is a problem that the end of the first peak is mistakenly judged as the end of the measurement, making it impossible to perform accurate measurements. The present invention was made in view of these problems, and its purpose is to enable accurate measurement at low temperatures, that is, to achieve highly accurate measurement with a large amount of sample. It is something.

[Means to solve the problem]

In order to achieve the above object, the organic carbon measuring device according to the present invention has devised a method for determining the peak end of data. In other words, even if the slope of the peak falls below a certain value, it is not considered to be the peak end at that point, but by continuing to monitor for a certain period of time, the second peak or the shoulder of the peak is discovered, and the true peak end is determined. The true peak area can be obtained by determining the true peak area.

【Example】

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows the configuration of an organic carbon measuring device provided by the present invention. The sample is injected into a combustion furnace with a carrier gas and vaporized, converting all organic carbon contained within the sample into carbon dioxide. The generated carbon dioxide passes through the pre-treatment section (gas-liquid separator and filter
It will appear as a peak above. The computer detects the time when the slope of the peak becomes smaller than the value as the peak end, and calculates the area of the peak up to this point as the amount of carbon dioxide generated, that is, the amount of total organic carbon. However, due to the above-mentioned reason, the peak does not appear in Figure 2 or Figure 3.
If the shape is as shown in the figure, the computer will become P1 in the figure.
The point in time is detected as the peak end, and the area of the peak at this point is miscalculated. Therefore, in the present invention, P
Even if 1 is detected, this is not recognized as the peak end, and by continuing to monitor for a certain period of time Δt (usually about 30 to 60 seconds), we can detect the rise of a new peak or the presence of a large negative slope. Check the true peak end P2
In other words, the true total organic carbon content can be obtained.

【Effect of the invention】

The present invention has the following effects. Regardless of the shape of the peaks, the total area of all peaks can be determined, making it possible to inject a large amount of sample into the device and perform accurate measurements.

[Brief explanation of drawings]

Figure 1 shows the configuration of the organic carbon measuring device provided by the present invention, Figure 2 shows an example of data when the peak is divided into two parts, and Figure 3 shows the configuration of the organic carbon measuring device provided by the present invention. shoulder (step)
This figure shows an example of data when .

Claims (1)

[Claims] (1) In an organic carbon measuring device having a sample component peak determination device, the determination device has a function of detecting the presence or absence of a second peak for a certain period of time after detecting the first peak end. An organic carbon measuring device featuring: