JPH05126821A - Toc meter - Google Patents

Abstract

PURPOSE:To enable the outputting of individual TOC values and a mean value with a single pen recorder along with higher reliability of measurement by performing a TOC measurement to determine a mean value thereof. CONSTITUTION:Measuring operation is controlled with a measurement control section 4 to perform a measurement a plurality of times at each measuring cycle to average individual TOC values with an averaging section 3. An output selecting section 5 selects the TOC values until the frequency of measurement set on the measurement control section 4 is reached and a TOC mean is selected after the set frequency of measurement is reached. An analog output section 10 outputs an output selected by the output selecting section 5 onto one output signal as analog signal.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a TOC meter for measuring TOC (total organic carbon) in a sample.

[0002]

2. Description of the Prior Art A TOC meter, which has a carrier gas supply section, a sample injection section, a combustion oxidation reaction section and a CO ₂ detection section, measures the TOC value in a sample and outputs an analog signal corresponding to the TOC value. There is a total. The TOC meter measures each sample once and outputs each TOC value as an analog signal. In the case of a sample with a gradual change in TOC concentration, it is measured in a relatively long period.

[0003]

However, the reliability is low because the measured values vary even if the measurement is performed only once for each sample. However, it is not performed to measure each sample a plurality of times and output the average value. The present invention increases the reliability of the measurement by performing the TOC measurement for each sample a plurality of times and obtaining the average value thereof, and simplifies the apparatus by outputting each TOC measurement value and the average value with one pen recorder. The purpose is that.

[0004]

FIG. 1 shows a control system according to the present invention. The control system of the TOC meter of the present invention comprises a measurement control unit 4 for controlling the measurement operation so as to measure a plurality of times in a certain measurement cycle, and an averaging unit 3 for averaging each TOC value.
And an output selection unit 5 that outputs each TOC value until the number of times of measurement set by the measurement control unit 4 is reached, and outputs an average value of TOC after the number of times of measurement set is reached,
The output selected by the output selector 5 is set as an analog signal 1
And an analog output section 10 for outputting on one output signal.

[0005]

2 is a block diagram showing a configuration for realizing the control system of FIG. The output of the detection unit 2 is captured by the MPU (microprocessor unit) 7, and the TOC value for the set number of times is output from the analog output unit 10 as an analog signal, and then the average value of those measured values is converted into an analog value. The signal is output from the analog output unit 10 as a signal. A memory 8 such as a RAM for temporarily storing the measured value is connected to the MPU 7. The averaging unit 3, the measurement control unit 4, and the output selection unit 5 in FIG. 1 are the MPU 7 in FIG.
And the memory 8. The MPU 7 also serves as a measurement control unit 4 that controls the measurement operation of the TOC meter, an arithmetic unit that includes an averaging unit 3 that performs an averaging operation, and an output selecting unit 5 that selects an output.

FIG. 3 shows a TOC meter of one embodiment. The sample flows into the flow-through type sample container 12 from the lower inlet, and the sample is discharged from the upper outlet. The sample in the sample container 12 is the sample injection part 14
A fixed amount is collected by and is switched to and guided to the TC reaction unit 16 or the IC reaction unit 18. The TC reaction section 16 is provided with a TC combustion tube filled with an oxidation catalyst, and a heating furnace is provided outside the TC combustion tube to heat the TC combustion tube. To the TC reaction section 16, pure oxygen gas or high-purity air from which CO ₂ and hydrocarbons have been removed is supplied from the carrier gas supply section 20 as a carrier gas at a controlled gas flow rate.
In the TC reaction section 16, all the carbon components in the supplied sample are converted into CO ₂ gas and guided to the measurement cell of the non-dispersion type infrared gas analyzer (NDIR) 22 of the CO ₂ detection section to be detected. In the IC reaction part 18, inorganic carbon is generated as CO ₂ gas, which is guided to the measurement cell of the NDIR 22 together with the carrier gas and detected. The sample injection unit 14 is a TC or IC
The standard solution 23 can also be injected for preparing the calibration curve of the above.

In order to process the detected value of NDIR 22,
As shown in FIG. 2, the MPU 7 is provided, the MPU 7 calculates the TOC value from the TC value and the IC value, and the analog output unit 10 is connected to the MPU 7 to output the TOC value to the recorder. Has been done. Reference numeral 26 is a measurement value display / printing unit for displaying and printing the measurement values.

The operation of one embodiment will be described with reference to FIGS. 4 and 5. In this example, a case will be described as an example in which TOC measurement is performed three times for each sample and then the average value is output. When one TOC measurement is completed, the analog output value is calculated from the measured value. When the number of times of measurement is less than the set number of times, in this case, three times, the calculated analog signal a ₁ is output, and the next TOC measurement of the sample is started. When the second TOC measurement is completed, the analog output value a ₂ is calculated from the measured value and output, and the third TOC measurement is performed. When the third TOC measurement is completed,
An analog output value is calculated from the measured value, and the analog signal a ₃ is output for 2 minutes. Next, 3 times T of the sample
An average of OC values is calculated to calculate an analog output value, and an analog signal of the average value is output. The output of the average value is continuously performed until the measurement of the sample in the next cycle is started and the first TOC measurement is completed (section B in FIG. 5). In this example, measurement is performed three times every hour, and the average value is output.
Since the average value, which is the most important value, continues to be output until the next measurement cycle, it is easy to distinguish between the individual value and the average value.

[0009]

According to the present invention, the TOC value is measured a plurality of times in a certain measurement cycle, and each measured value and the average value thereof are output as analog signals on one output signal. In addition to high reliability, the single-pen recorder can record both the individual measurement value and the average value, which simplifies the apparatus and facilitates the discrimination between the individual measurement value and the average value.

[Brief description of drawings]

FIG. 1 is a block diagram showing a control system of the present invention.

FIG. 2 is a block diagram showing a configuration for realizing FIG.

FIG. 3 is a configuration diagram showing a TOC meter of one embodiment.

FIG. 4 is a flowchart showing the operation of the embodiment.

5 is a diagram showing waveforms recorded in the recorder as a result of the operation of FIG.

[Explanation of symbols]

 2 detection unit 3 averaging unit 4 measurement control unit 5 output selection unit 7 MPU 8 memory 10 analog output unit

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hiroaki Matsuhisa 1 Nishinokyo Kuwabara-cho, Nakagyo-ku, Kyoto City, Kyoto Prefecture Shimazu Corporation Sanjo Factory

Claims (1)

[Claims] 1. A batch type TOC meter equipped with a carrier gas supply section, a sample injection section, a combustion oxidation reaction section and a CO ₂ detection section to measure a TOC value in a sample and output an analog signal corresponding to the TOC value. In, a measurement control unit that controls the measurement operation so as to measure a plurality of times in a certain measurement cycle, an averaging unit that averages each TOC value, and each measurement control unit until the number of times of measurement set is reached. An output selection unit that outputs the TOC value and outputs the TOC average value after reaching the set number of times of measurement, and an analog output unit that outputs the output selected by the output selection unit as an analog signal on one output signal. TOC characterized by having
Total.