JPS5925606B2 - Solvent degassing equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a solvent degassing device, and in particular, the solvent container is configured to be deformable so that the solvent volume can be sealed without creating a gas phase volume after the gas phase in the solvent container is evacuated. According to
This is intended to prevent the gas from redissolving.

Oxygen, nitrogen, etc. in the air are dissolved in ordinary solvents.

In order to use the solvent for analysis such as liquid chromatography, it is necessary to reduce these dissolved gases as much as possible. As a method for degassing the dissolved gas of such a solvent, a method is known in which the gas phase of a solvent container is evacuated using an exhaust pump. However, after evacuation is complete, the gas phase is normally returned to normal pressure in order to perform suction and transfer using the liquid pump without any problems, and therefore, redissolution of oxygen, nitrogen, etc. into the solvent is unavoidable. It was difficult to use this solvent continuously for a long time. This invention was made in view of these circumstances,
The specific configuration is that in a solvent degassing device that exhausts the gas phase in a solvent container using an exhaust pump, the solvent container can be constantly deformed in accordance with the solvent volume after the gas phase in the solvent container is exhausted. A solvent degassing apparatus is constructed such that there is substantially no gas phase volume within the solvent container.

That is, in the present invention, the solvent container is configured to be deformable so as to always surround only the solvent volume, thereby preventing the formation of a gas phase itself in the solvent container that would cause re-dissolution.

Of course, since there is no reconsideration, the solvent can be used continuously for a long time. Furthermore, since the solvent itself can be returned to normal pressure, there is no problem with liquid feeding. The present invention will be described in detail below based on embodiments shown in the figures.

Note that this invention is not limited by this. First, in FIG. 1, a solvent degassing device 1 includes a container body 3 and a plunger 4 that substantially constitute a solvent container 2.
, a means 5 for moving the plunger up and down, and a gas phase exhaust means 6.

The solvent container main body 3 is a cylindrical container body having an opening at the top, and is connected to an air and solvent switching suction passage 8 with a solenoid valve 7 interposed therebetween and a liquid feeding pump (not shown) with a solenoid valve 9 interposed therebetween. The inside communicates with the solvent feeding path 10 .

The plunger 4 has a cylindrical shape and is inserted into the opening of the solvent container main body 3 so as to be vertically movable, and forms a lid of the solvent container.

11 is a seal ring for sealing the inside of the solvent container 2.

A conduit 14, which is opened at the lower surface of the plunger, extends into the atmosphere, and is connected to a switching valve 13, which will be described later, is a plunger support pin.

The vertical moving means 5 includes a vertical gear shaft 15 that can be rotated in forward and reverse directions by a drive motor (not shown), and a support base 16 for the vertical gear shaft 15.
It is composed of an arm 17 that is engaged with a gear shaft and can be moved up and down by the forward and reverse rotation of the gear shaft, and this arm 17 comes into contact with the lower part of the plunger support pin 14 during upward movement and forces the plunger 4. can be raised to a certain level. The gas phase exhaust means 6 comprises an exhaust pump 18 and a switching valve 13 which selectively connects the suction side 19 of the exhaust pump to the atmospheric side 20 or to the conduit 12. Next, the operation of the solvent degassing apparatus 1 having the above configuration will be explained. (stomach)
The solenoid valve 7 is opened, the solenoid valve 9 is closed, and the switching valve 13 is brought into communication between the suction side 19 and the atmosphere side 20 of the exhaust pump.

Then, the plunger 4 is slightly raised by forward rotation of the drive motor, and atmospheric air is sucked into the solvent container body 3 through the switching suction passage 8. Next, a separately prepared solvent supply source 21 is connected to the switching suction path 8, and the solvent is sucked into the solvent container 2 through the switching suction path 8 by continuing the upward movement of the plunger 4 (the state shown in FIG. 1). (b) After the suction of the solvent is completed, the solenoid valve 7 is closed, the arm 17 is maintained in this state, and the exhaust pump 18 is started, and the switching valve 13 is then switched to communicate the suction side 19 of the exhaust pump with the conduit 12. do it like this.

In this way, the gas phase portion G is evacuated, and if necessary, in order to sufficiently evacuate the solvent, the solvent S is stirred using ultrasonic waves or a stirrer to promote degassing. ←→ After the solvent has been degassed, switch the switching valve 13 to the state (A) to stop the exhaust pump 18, and at the same time rotate the drive motor in the opposite direction to lower the arm 17 to the lowest end (the position indicated by the dashed-dotted line). .

In this way, the plunger 4 is no longer supported by the arm 17 and falls naturally, so that its lower surface comes into contact with the liquid level of the solvent S. Of course, this substantially eliminates the gas phase portion G, and the solvent S returns to normal pressure. (-) Next, the solenoid valve 9 is opened, and the solvent S is suitably sucked and sent to an analysis section such as a liquid chromatograph using a liquid sending pump. At this time, the liquid level of the solvent S in the solvent container 2 decreases in response to the feeding of the solvent, but correspondingly, the plunger 4 descends while maintaining the close contact state. As a result, the solvent is maintained at almost atmospheric pressure, and is suctioned and pumped without any problems, yet at the surface of the solvent. Since there is almost no contact with air, re-dissolution of air can be prevented and a degassed state can be maintained for a long time. In the above embodiments, the solvent container is composed of a container main body and a lid (plunger) that can change the sealed internal volume of the main body, but unlike this, the solvent container main body is made of a bellows that can change the sealed internal volume. It can also be configured.

For example, in FIG. 2, the solvent degassing device 1a includes a container body 3a made of bellows that substantially constitutes the solvent container 2a, and a plunger 4a that seals and fixes the upper opening of the container body 3a.
It mainly consists of an outer container 22a, a plunger vertical movement means 5a, and a gas phase exhaust means 6a.

Note that configurations corresponding to the embodiment shown in FIG. 1 are shown with the same reference numerals and a suffix "a". The outer container 22a houses the solvent container 2a,
The plunger 4a is made to protrude into the atmosphere from the opening 23a so as to be movable up and down.

24a is a sealing ring for sealing the inside of the outer container;
Reference numeral 5a designates a second conduit which is connected within the outer container to either the conduit 12a or the atmosphere side 27a by means of a switching valve 26a.

The solvent degassing apparatus 1a having the above structure operates almost in the same way as in the previous embodiment.

However, the switching valve 26a is not connected to the second conduit 25a in the state (A).
is connected to the atmosphere side 27a, and the second conduit 25a is connected to the conduit 12a when the switching valve 13a is switched. Furthermore, in Hira, when switching the switching valve 13a, the switching valve 26a is
Return to the state of As in the embodiment shown in FIG. 1, redissolution of air can thus be prevented and a degassed state can be maintained for a long time. The structure of this solvent degassing device 1a can be simplified because the seal ring 24a is completely isolated from the solvent.

[Brief explanation of the drawing]

FIG. 1 is a functional explanatory diagram showing one embodiment of the solvent degassing apparatus of the present invention, and FIG. 2 is a functional explanatory diagram of main parts of another embodiment. 1... Solvent degassing device, 2... Solvent container, 3... Container body, 4... Plunger, 5... Top and bottom. Transportation means, 6... Gas phase exhaust means, 18... Exhaust pump, G...
... Gas phase, S... Solvent.

Claims (1)

[Claims] 1. In a solvent degassing device that exhausts the gas phase in a solvent container using an exhaust pump, after exhausting the gas phase in the solvent container,
1. A solvent degassing device characterized in that the solvent container is configured to be always deformable in accordance with the solvent volume, thereby substantially eliminating the presence of gas phase volume within the solvent container.