JP3060883B2 - Process gas chromatograph - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a process gas chromatograph used for analyzing components of a process, and more particularly, to a process gas chromatograph capable of measuring components in a sample with high accuracy.

[0002]

2. Description of the Related Art In a process gas chromatograph, a sample separated from a process is introduced to a separation column, developed chromatographically with a carrier gas, and each component separated in the separation column is detected by a detector to detect the concentration of the component in the sample. Is measured. The process is monitored and controlled so that each component has an appropriate concentration based on the concentration measured by the process gas chromatograph. In order to perform such monitoring and control of the process in a timely and accurate manner, a sample extracted from the process is promptly sampled and measured by a process gas chromatograph.

[0003]

In such a conventional process gas chromatograph, when a sample is sampled in a liquid state, the amount of sampling is usually 1 to 3.
Since the sample volume is as small as μL, the amount of sample (measured value) fluctuates greatly even if fine bubbles and dust are present or generated in the sample solution. There was a drawback that the property was poor.

[0004] The present invention has been made in view of such a point, and it is intended to verify, at each sampling, whether or not the amount of a sample sampled by a measuring section is appropriate. An object of the present invention is to provide a process gas chromatograph that can ensure the reliability of the analysis result of a sample detected by the method and can monitor and control the process.

[0005]

According to the present invention, a sample sampled in a measuring section is vaporized by a vaporizer and guided to a column, and separated components are analyzed by a detector. In a process gas chromatograph, a thermal conductivity detector provided between the vaporizer and the column to detect an amount of a sample vaporized by the vaporizer, and a sample detected by the thermal conductivity detector Comparing means for comparing data relating to the amount of the sample with data obtained when the sample from the measuring section is properly guided to the thermal conductivity detector, and the value compared by the comparing means is a predetermined value. When the value deviates from the value, it is determined that there is an abnormality in the sampling.

[0006]

The components of the present invention operate as follows.
The thermal conductivity detector detects the amount of the sample vaporized by the vaporizer and sent to the separation column. The comparing means simply compares the data on the amount of the sample detected by the thermal conductivity detector with the data when the sample is properly guided from the measuring section to the thermal conductivity detector and measured, or by statistical means. Evaluation is determined.

[0007]

An embodiment of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a configuration block diagram showing one embodiment of the process gas chromatograph of the present invention. In the figure,
Reference numeral 1 denotes a sampling valve, and 1A denotes a measuring unit in the sampling valve, for example, for collecting a sample in 1 μL.
The sample weighed by the measuring section 1A is supplied to the sampling valve 1
Is switched to the vaporizer 2 by the carrier gas.

[0008] A sample vaporized by the vaporizer 2 is partially separated by a splitter 3 and is subjected to a sample validation detector 4 (SVD, hereinafter referred to as a thermal conductivity detector 4).
Transported to The thermal conductivity detector 4 has a small internal volume,
The amount of the sample is detected by measuring a value based on the thermal conductivity of the carrier gas containing the sample supplied from the vaporizer 2 and having no or few diffusion portions in the flow passage.

The amount (peak value) of the sample measured by the thermal conductivity detector 4 is the amount of the sample supplied to the separation column 6 via the backlash column 5 and is, for example, 1 μm.
The L sample is normally guided from the measuring section 1A to the thermal conductivity detector 4 and compared with data (peak value) when measured.
Note that this 1 μL is an amount obtained by subtracting a portion divided by the splitter. Reference numeral 7 denotes a comparison unit which compares the amount of the sample measured by the thermal conductivity detector 4 with data obtained when the sample is normally collected by the 1 μL measuring unit.

When the comparison result in the comparison unit 7 deviates from a preset reference value, for example, when the peak value measured by the thermal conductivity detector 4 decreases, it is determined that there is abnormality in the sampling, The measurement data of the detector 8 is excluded from the measurement result, and an alarm is issued.

[0011]

As described in detail above, the process gas chromatograph of the present invention is provided with a thermal conductivity detector in front of the separation column to determine whether the amount of the sample sampled in the measuring section is appropriate. Since the verification is performed for each sampling, the reliability of the analysis result of the sample measured by the final detector can always be ensured.

[Brief description of the drawings]

FIG. 1 is a configuration block diagram showing one embodiment of a process gas chromatograph of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Sampling valve 4 Thermal conductivity detector 6 Separation column 7 Comparison part

Claims (1)

(57) [Claims] 1. A process gas chromatograph in which a sample sampled in a measuring section is vaporized by a vaporizer and led to a column, and separated components are analyzed by a detector. The process gas chromatograph is provided between the vaporizer and the column. A thermal conductivity detector for detecting the amount of the sample vaporized by the vaporizer; and data relating to the amount of the sample detected by the thermal conductivity detector, and the heat conductivity detector for appropriately detecting the sample from the measuring unit. Comparing means for comparing the data at the time measured by being guided to, wherein when the value compared by the comparing means deviates from a predetermined value, it is determined that there is an abnormality in the sampling. Process gas chromatograph characterized by the following.