JPH0552830A - Process gas chromatograph - Google Patents

Abstract

PURPOSE:To adjust an apparatus in a stably operating state by sampling a certain amount of carrier gas and process sample and automating operation of two switch valves having four connection ports and three separation columns. CONSTITUTION:When a sample sampling valve is turned ON, its internal flow path is changed over, so that process sample in a measuring tube is separated through connection ports 3a, 3b of a switch valve 3 into components to be measured and unnecessary components at a separation column 4a. The components to be measured come through connection ports 5a, 5b of a switch valve 5 to a separation column 4c to be separated into respective components. If the switch valves 3, 5 are simultaneously turned ON at this time, the internal flow path changes from solid lines to broken lines, so that the unnecessary components remaining in the column 4a are carried oppositely to carrier gas and discharged through a restrictor 3g. On the other hand, a signal of a detector 6 is processed in an integration circuit and a control circuit 8 to have concentration, etc., of the components to be measured calculated, which is output as a concentration signal S2. An instruction signal S3 drives a sample sampling valve 2 and the switch valves 3, 5 via a valve driving circuit 9.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a sampling valve and a first and a first sampling valve.
The present invention relates to a process gas chromatograph that can be easily adjusted to a stable operation state by automatically setting the operation of a switching valve and automatically adjusting the timing of cutting a component to be measured.

[0002]

As is well known, in a process gas chromatograph, a sample containing a component to be measured is introduced into a separation column by a carrier gas to be developed, and an elution component of the separation column is detected by a detector, and the detected signal is detected. The concentration of the component to be measured is calculated from the peak area and peak height value of the chromatogram drawn on the basis.

Further, the process gas chromatograph is often used for control and management of the process, and it is required that only the required measured component can be stably measured for a long time in the shortest time. To meet these demands,
In the process gas chromatograph, a switching device for the flow passage is provided in the development flow passage to guide the component to be measured to the detector in a short time, and to guide unnecessary components that contaminate the development flow passage and the detector to the outside of the system. It has become.

However, setting the operating time of such a switching device has a drawback that it takes a lot of time due to experience.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the drawbacks of the conventional example, and an object thereof is to automatically set the cutting timing of the component to be measured to easily achieve a stable operation state. It is to provide an adjustable process gas chromatograph.

[0006]

In the process gas chromatograph, a carrier gas cylinder, a sampling valve for sampling a fixed amount of a process sample, and first to fourth aspects are features of the present invention for solving the above problems. Switching valve having a connection port and a restrictor serving as fluid resistance, a separation column, a second switching valve having first to fourth connection ports and driven simultaneously with the first switching valve, and the first switching valve. A first separation column and a second separation column that are connected in parallel so as to be sandwiched between the switching valve and the second switching valve; a third separation column that is serially connected to these separation columns and the second switching valve; A detector for detecting the eluate of the third separation column, an integrating circuit for integrating the output of the detector, a control circuit, and the sampling valve and the first and second switching valves receiving the output of the control circuit. And a valve drive circuit to drive Serial operations sampling valve and the first and second switching valves automatically set in that so as to adjust to a stable operation state.

[0007]

The present invention operates as follows. That is, when the sample collection valve is turned on, the process sample in the measuring pipe is collected and passed through the first switching valve to be separated into the measured component group and the unnecessary component in the first separation column. The group of components to be measured separated from the unnecessary components in this way passes through the second switching valve to reach the third separation column and is separated into each of the components to be measured. If the first and second switching valves are turned on at the same time when the measured component group passes through the second switching valve, the internal flow paths of these switching valves are switched, and the unnecessary components remaining in the first separation column are switched. Is transported to the carrier gas and discharged through the first switching valve and the restrictor.

On the other hand, the detection signal of the detector is guided to an integration circuit and integrated, and then is guided to a control circuit and subjected to predetermined arithmetic processing to calculate the concentration of the component to be measured and the like and output as a concentration signal. .. In addition, a measurement concentration range or the like is set in advance in the control circuit by an input signal, and a command signal output from the control circuit drives the sampling valve and the first and second switching valves via the valve drive circuit. It has become.

[0009]

The present invention will be described in detail below with reference to the drawings. FIG. 1 is an explanatory diagram of the configuration of the embodiment of the present invention. In this figure, 1 is a carrier gas cylinder, 2 is a sample sampling valve for sampling a fixed amount of process sample supplied and discharged as indicated by thick arrows, and 3 is first to fourth connection ports 3a to 3d and fluid resistance. First switching valve having restrictor 3g, 4a
4c is a separation column, 5 is the first to fourth connection ports 5a to 5
a second switching valve having d, 6 an integrating circuit, 8 a control circuit,
Reference numeral 9 is a valve drive circuit.

In the embodiment of the present invention having such a structure, first, the switching valves 3 and 5 are turned off, and the internal flow paths thereof are in the connection state of the solid line in FIG. In this state, the carrier gas supplied from the carrier gas cylinder 1 is the sampling valve 2 → the first and second connection ports 3a and 3b of the switching valve 3 → the separation column 4a → the first and second connection ports of the switching valve 5. 5a, 5b → separation column 4c → detector 6 and the sampling valve 2
The carrier gas that has been diverted upstream of the
The third connection ports 5d and 5c flow to the separation column 4b to the fourth and third connection ports 3d and 3c of the switching valve 3 to the restrictor 3g.

The process sample is filled in the measuring pipe (not shown) of the sample collecting valve 2. Therefore, when the sample collection valve 2 is turned on, the internal flow path is switched and the process sample in the measuring pipe is collected. This process sample passes through the first and second connection ports 3a, 3b of the switching valve 3 and is separated into a group of measured components and unnecessary components by the separation column 4a.

The component to be measured separated from the unnecessary component in this way passes through the first and second connection ports 5a and 5b of the switching valve 5 to reach the separation column 4c and is separated into each component to be measured. When the measured components pass through the first and second connection ports 5a and 5b of the switching valve 5 and the switching valves 3 and 5 are turned on at the same time, the internal flow paths of the switching valves 3 and 5 are changed from the solid line connection state. It is switched to the broken line connection state. Therefore, the unnecessary components remaining in the separation column 4a are conveyed in the opposite direction to the carrier gas, and are discharged through the second and third connection ports 3b and 3c of the switching valve 3 and the restrictor 3g.

On the other hand, the detection signal of the detector 6 is the integration circuit 7
To the control circuit 8 to perform predetermined arithmetic processing to calculate the concentration of the component to be measured and the like, and output it as the concentration signal S ₂ . Further, the control circuit 8 can be set in advance with a measurement concentration range and the like by the input signal S ₁ . Further, the command signal S ₃ output from the control circuit 8 drives the sampling valve 2 and the switching valves 3 and 5 via the valve driving circuit 9.

FIG. 2 is a chromatogram prepared by introducing the detector detection signal detected as described above to a recorder not shown, and in the figure, the horizontal axis represents the peak height of each component. The vertical axis indicates time (t).

[0015]

According to the embodiments of the present invention described in detail above, the operation of the switching valve indispensable to the process gas chromatograph can be automatically set, and the process gas chromatograph can be easily adjusted to a stable state. is there. Therefore, according to the present invention, it is possible to realize a process gas chromatograph in which the timing of cutting the component to be measured can be automatically set and easily adjusted to a stable operating state.

[Brief description of drawings]

FIG. 1 is a structural explanatory view of an embodiment of the present invention.

FIG. 2 is a chromatogram created using an example of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Carrier gas cylinder 2 Sampling valve 3,5 switching valve 4a-4c Separation column 6 Integration circuit 8 Control circuit 9 Valve drive circuit

Claims (1)

[Claims] 1. A carrier gas cylinder, a sample collection valve for collecting a fixed amount of a process sample, a first switching valve having first to fourth connection ports and a restrictor serving as a fluid resistance, a separation column, and first to first. A second switching valve having a fourth connection port and driven simultaneously with the first switching valve, and first and second separation columns connected in parallel so as to be sandwiched between the first switching valve and the second switching valve. A third separation column connected in series with these separation columns via the second switching valve, a detector for detecting the eluate fluid of the third separation column, and an integrating circuit for integrating the output of the detector And a valve drive circuit that receives the output of the control circuit and drives the sampling valve and the first and second switching valves, and operates the sampling valve and the first and second switching valves. Characterized by automatically setting and adjusting to a stable operating state B Seth gas chromatograph.