JPH0515076Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to an apparatus for sampling gas dissolved in a liquid phase.

(Prior art) For example, the lifespan of insulating oil sealed in a transformer is tested by detecting organic gas components contained in the insulating oil. If exposed, there is a problem that target gas components may volatilize or conversely, miscellaneous gases in the environment may dissolve, causing measurement errors.

In order to solve this problem, the injection needle A is inserted through the bottom surface of the bottomed cylindrical body as shown in FIG.
Using a sampling device consisting of a holder B with a fixed holder B and a tubular container D maintained in a vacuum state with a rubber stopper C in advance, insert the container D into the holder B with the rubber stopper C side facing the injection needle A, and insert the container D into the holder B. The container D is pushed into the rear end of the injection needle A with the tip of the needle A immersed in the sample, and the sample liquid is injected into the container D using vacuum pressure.

According to this method, it is possible to collect samples without exposing them to environmental gases such as air.
In order to analyze the gas dissolved in this sample, the sample must be removed from the container, which is disadvantageous in that the gas volatilizes and miscellaneous gases dissolve.

(Purpose) The present invention was developed in view of these problems, and its purpose is to sample dissolved gas in a liquid contained in a sealed container without bringing it into contact with external environmental gas. Our goal is to provide equipment that can.

(Summary of the invention) That is, the present invention is characterized by: a first injection needle having a length that reaches at least the liquid phase of the sample container and whose rear end is connected to a carrier gas source; It has an inner diameter that allows a ventilation path to be formed when inserted, and the rear end is tightly plugged with a rubber stopper.
Furthermore, by providing a second injection needle with a gas outlet on the side, the bubbling of the carrier gas allows the simple operation of inserting the injection needle into the sampling container to dissolve the dissolved gas in the sample liquid. The point is to extract the gas components that are present.

(Example) Therefore, the details of the present invention will be explained below based on the illustrated example.

FIG. 1 shows an embodiment of a dissolved gas measuring device to which the gas sampling device of the present invention is applied, and the reference numeral 10 in the figure is the gas sampling device which is a feature of the present invention, and is shown in FIG. 1st
A hole 13a is formed in the base 13 to accommodate the base 12a of the second injection needle 12 through which the injection needle 11 can be inserted with a space formed therein.
The base 12a of the injection needle 12 is fixed with an adhesive 17 that also serves as a seal, and a through hole communicating with the base of the second injection needle is bored to provide a gas outlet 14. The rear end can be sealed with a rubber stopper 15, and the first injection needle 11 can be immersed in the sample liquid in the container D by passing through the rubber stopper 15.

A tube 21 is attached to the gas outlet 14 through a measurement cell 22 to an inlet of the pump 23 (FIG. 1), and a tube 24 is attached to the rear end of the first injection needle 11 to the outlet of the pump 23. It is connected to the. In the figure, reference numeral 25 indicates a liquid trap that also serves as a buffer tank, and 27 indicates a measurement circuit that displays the gas concentration based on a signal from a gas sensor 26 in the measurement cell.

In this example, using the liquid sampling device shown in FIG. 5, the container D is inserted into the holder B with the rubber stopper C side facing the injection needle A, and the tip of the injection needle A is immersed in the sample liquid. Push the container D into the other end of the injection needle A, and collect the sample liquid in the container D.

Fix the sampling container D containing the liquid sample with its rubber stopper C facing upward, and insert the second injection needle 1
2 is passed through the rubber stopper C, and its tip is positioned in the gas phase E of the glass container D (FIG. 3I). When the first injection needle 11 is inserted through the rubber stopper 15 in this state, it is guided by the funnel-shaped part of the base 12 of the second injection needle and enters the second injection needle 12 ().
It passes through the hole in the container rubber stopper C previously pierced by the second injection needle 12.

When the pump 23 is activated when the tip of the second injection needle 12 is located at the bottom of the container, the tube 2
1, 24, measurement cell 22, and even trap 25.
The carrier gas present therein is pumped by the pump 23 and delivered to the first injection needle 11 . As a result, the carrier gas is injected into the sample liquid F to generate bubbles, and the gas components and volatile components dissolved in the sample are discharged into the gas phase E of the container D.
and the second injection needles 11 and 12, and are discharged to the discharge port 14. The carrier gas containing the target component flows into the measurement cell 22,
It is detected by the gas detector 26 disposed here and discharged into the sample liquid F via the pump 23 again. By repeating this process cyclically, gas components in the sample F are extracted at a high concentration and sent to the measurement cell 22. Note that the sample liquid that has entered the tube 21 during this circulation process is collected by the trap 25 and cannot flow into the measurement cell 26.

Needless to say, since the sample is not exposed to the external environment from the time of taking the sample to the time of discharging the dissolved gas, only the gas dissolved in the sample liquid F and the Kiya gas are supplied to the measurement cell 22.

In this way, when the measurement of dissolved gas is completed, the first and second injection needles 11 and 12 are pulled out and inserted into the next container D to enable measurement. Even if left as is, the rubber stopper C still maintains a liquid-tight state, so the sample liquid will not scatter.

In this embodiment, the base of the injection needle is embedded in the base, but as shown in FIG. A constricted through hole 32 is bored, and only the needle portion 33 having an inner diameter large enough to accommodate the first injection needle and form a space on the distal end side thereof is airtightly fixed, and the through hole 32 is It is clear that the same effect can be achieved even if a communicating gas exhaust port 34 is provided.

(Effects) As described above, according to the present invention, the first injection needle has a length that reaches at least the liquid phase of the sample container and whose rear end is connected to the carrier gas source;
The sampling container is equipped with a second injection needle that has an inner diameter that allows a ventilation passage to be formed when the injection needle is inserted, the rear end of which is sealed with a rubber stopper, and a gas discharge port provided on the side. By simply inserting a syringe needle into the container, gas components dissolved in the sample liquid can be extracted by bubbling carrier gas without exposing them to air. Not only can the liquid be exchanged, simplifying the on-site dissolved gas analysis work, but also
Since the first injection needle is inserted after the thick and durable second injection needle is inserted into the container, bending or the like can be prevented.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram showing an embodiment of a dissolved gas measuring device using the gas sampling device of the present invention;
FIG. 2 is a sectional view showing one embodiment of the gas sampling device, FIG. 3 is an explanatory diagram showing how to use the device shown in FIG. 2, and FIG. 4 is a sectional view showing another embodiment of the present invention. FIG. 5 is a sectional view showing an example of a sampling device. 10... Dissolved gas sampling device, 11...
First injection needle, 12...Second injection needle, 13...
Base, 14... Gas outlet, 15... Rubber stopper, 2
1, 24...Tube, 22...Measurement cell, 23
...Pump, D...Sample container.

Claims (1)

[Scope of utility model registration request] a first injection needle having a length that reaches at least the liquid phase of the sample container and whose rear end is connected to a carrier gas source; and an inner diameter that allows a ventilation passage to be formed when the injection needle is inserted; A dissolved gas sampling device consisting of a second injection needle whose rear end is hermetically sealed with a rubber stopper and which has a gas outlet on the side.