JPS5823121B2 - Rotary vacuum distillation equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a rotary vacuum distillation apparatus used for concentrating various sample liquids.

Conventionally, during operation of a rotary vacuum distillation apparatus for concentrating a sample liquid, the operator constantly monitors the decrease in the sample liquid in the flask.
Sample liquid is replenished manually, but since high-magnification concentration requires a long time, there was a need for a device that could perform fully automatic concentration.

In response to the conventional demand, the present invention detects the liquid level of a sample liquid in a rotating flask and automatically stops or starts supplying the sample liquid into the flask to maintain a constant liquid level in the flask. To provide a rotary vacuum distillation device that can be maintained.

In Fig. 1, 1 is a hollow heat exchange cylinder made of glass with an open front end, and a metal ring 2 fixed to the front end is fixed to a stand 3, and the rear end is fixed to another stand 4. Downward tilted state (this is supported).

At the front end of the heat exchange tube 1, the open end of a glass concentrating transparent flask 5 with one end open is connected to the heat exchange tube 1 in a freely rotatable and airtight manner in communication with the inside of the heat exchange tube 1 via a rotation joint 6. Approximately the front half of the flask 5 is immersed in the heated water 8 of the heating bath 7.

As the mechanism for driving the rotation of the flask 5, a worm gear 9 is fixed to the outer peripheral surface of the rotation joint 6, a motor 10 is fixed to the stand 3, and a worm 11 is fixed to the output shaft O of the motor. They are interlocking.

Reference numeral 12 denotes a cooling pipe installed inside the heat exchange cylinder 1, and a discharge pipe 14 is connected to the west end of the cooling water supply pipe 1o-1 at one end thereof.

Reference numeral 15 denotes a sample liquid supply pipe, which extends from the rear end of the heat exchange cylinder 1 into the cylinder 1 (the front end of which extends into the flask 5, and whose rear end extends into the inside of the sample liquid tank 16). Extends into the sample solution.

The sample liquid in the tank 16 is in contact with the atmosphere through the ventilation pipe 17.

18 is an aspirator for decompression, which is connected to the heat exchange cylinder 1 through a pipe 19.
The inside of the heat exchange tube 1 and flask 5 is maintained at a constant negative pressure.

20 is a solenoid valve that opens and closes the sample liquid supply pipe 15.

The liquid level detection switch for the sample liquid 25 in the concentration flask 5 has the following configuration.

Stands 21 and 22 are erected on both left and right sides of the heating bath 7,
The emitter 23 on one stand 2Ll and the receiver 24 on the other stand 22ζ are fixed respectively, and these emitters 2
3 and the photoreceiver 24 are positioned appropriately higher than the liquid level of the sample liquid as shown in the second figure, and are tilted downward toward the flask 5 at symmetrical positions about the vertical center plane VG of the flask 5. There is.

The light projector 23 is a normal one that includes a built-in light source such as an infrared light source or a visible light source such as a light emitting diode, and a lens system, and projects a light beam having a fixed light projection angle α onto the flask.

The light receiver 24 includes a phototransistor, a photodiode,
It is a normal device that includes a photoelectric element such as a CDS and a lens system, and has a fixed light receiving angle or light receiving range angle β.

This light receiver 24 is connected to the electromagnetic valve 20 via an amplifier 26.

The positional relationship between the emitter 23 and the receiver 24 is as follows:
The reflected light flux from the liquid surface in the flask 5 of the projected light flux No. 3 is incident on the light receiving angle β of the light receiver 24.

Note that the range of the reflected light flux that can be detected by the light receiving angle β of the light receiver 24 varies depending on conditions such as the height of the light emitter 23 and the light receiver 24 from the liquid surface, the degree of inclination, and the like.

In FIG. 2, the upper limit of the light receiving range at the intersection of the light emitting flux and the light receiving angle β is a1, and the lower limit is b, and when the liquid level of the sample liquid 25 in the flask 5 is between a and b, the light emitter 230 is reflected by the liquid surface, and the reflected light beam enters within the acceptance angle β and is received by the receiver 24. However, if the liquid level is above a or below b, the reflected light beam is reflected from the liquid surface. Since the reflected light beam does not enter within the acceptance angle β, the light receiver 24 does not receive the light.

Thereby, it is detected that the liquid level in the flask is within the a-b range or that it has fluctuated outside the a-b range.

In this example, when the reflected light flux Q is incident within the acceptance angle β, the light receiver 24 generates an OFF signal to close the solenoid valve 20, and when the reflected light flux is not incident within the acceptance angle β, the light receiver 24 generates an OFF signal that closes the solenoid valve 20.
A circuit is designed to generate a 0 open<ON signal.

By rubbing Q like this, the liquid level in the flask will be within the light receiving range a.
When the liquid level is between -b, the solenoid valve 20 is closed, but the liquid level is between b.
Thereafter, when the Q drops, the solenoid valve 20 is opened to replenish the sample liquid into the flask 5.

The operation of this device will be explained next.

A certain amount of sample liquid is supplied into the flask 5, and with the liquid level between points a and b in FIG. 2, the flask 5 is heated by the heating bath 7, and the flask 5 is rotated by the drive of the motor 10. , cooling water is sent to the cooling pipe 12 to cool and liquefy the sample liquid vapor flowing into the heat exchange tube 1 from the open end of the flask 5, and the inside of the heat exchange tube 1 and the flask 5 is heated to a predetermined position by the drive Q of the decompression aspirator 18. At the same time, the distilled liquid in the heat exchange column 1 is discharged through the tube 19, and this process is continued to concentrate the sample liquid in the flask 5.

During this time, the reflected light beam from the liquid surface of the light emitter 23 is emitted onto the light receiver 24ζ, and an OFF signal from the light receiver closes the electromagnetic valve 20 to cut off the supply of the sample liquid.

When the liquid level of the sample liquid 25 in the flask 5 drops below the point shown in FIG.
0 is opened, whereby the sample liquid in the tank 16 is replenished into the flask 5 through the supply pipe 15 due to the negative pressure in the flask 5.

Due to replenishment, the liquid level in the flask rises, and when it reaches a level above light, the electromagnetic valve 20 is closed again by the OFF signal from the light receiver 24.

Thereafter, as the sample solution is concentrated, new sample solution is repeatedly replenished.

In addition, since the heated water in the heating bath 7 decreases as the work continues, the water level is detected using, for example, a normal liquid level switch and water is replenished as appropriate.

On the upper side, when the liquid level exceeds the lower limit of the light receiving range, O
The FF signal immediately closes the solenoid valve 20 to stop supplying the sample liquid, but in another embodiment, a timer delays the closing of the solenoid valve 20 for a certain period of time, thereby replenishing the sample liquid to the middle of the light receiving range a to b. The composition O can be rubbed.

As yet another embodiment, an ON signal is transmitted when the light receiver 24 receives light, and an OFF signal is transmitted when the light receiver 24 is not receiving light, so that when the liquid level is within the light receiving range 3 to 5, the sample solution is replenished. In some cases, the replenishment is stopped when the liquid level reaches the upper limit a.

Note that the liquid level in the flask 5 may become finely undulating due to the rotation of the flask 5 or the replenishment of the sample liquid. After a certain time delay, solenoid valve 2
By rubbing Q so as to transmit the signal to 0, it is possible to prevent disturbances in liquid level detection due to waving.

In the liquid level detection switch, preferably the floodlight 23
It is desirable that the center line of the zero light projection axis and the receiving angle β of the light receiver 24 be perpendicular to the glass surface Q of the flask 5.

This is because the refractive index of the water layer adhering to the glass and glass Q is minimized.

As another example of the liquid level detection switch, the above-mentioned floodlight 23
The above light projector 23 and light receiver 24 can be replaced by a parallel light projector and a parallel light receiving range receiver. You can also do that.

The rotary vacuum distillation apparatus of this invention accurately detects fluctuations in the liquid level of a sample liquid in a rotating flask, and sends a signal to a solenoid valve to open and close it, thereby adding new sample liquid to the flask. It is possible to automatically replenish the required amount and maintain a constant liquid level inside the flask.Therefore, the operator does not have to constantly monitor the decrease in sample liquid and replenish the sample liquid manually, and the system is fully automatic. It can be concentrated using methane, and its utility value is extremely high.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention; FIG. 1 is a partially cutaway side view of the device, and FIG. 2 is an enlarged cutaway end view taken along line 1--2 in FIG. 1. 1...Heat exchange cylinder, 5...Transparent flask for concentration, 7...Heating bathtub, 8...Heating water, 12... Cooling pipe, 13... Cooling water supply pipe, 14... Discharge pipe, 15... Sample liquid supply pipe, 16... Sample liquid tank, 18.・
・Aspirator for pressure reduction, 20... Solenoid valve, 23
......Emitter, 24...Receiver, 25.
...sample liquid, α...projection angle, β reception angle.

Claims (1)

[Claims] 1. The open end of the concentrating flask is connected to the open front end of the hollow heat exchange cylinder in a freely rotatable and airtight manner in communication with the heat exchange cylinder, and the inside of the heat exchange cylinder is connected to the heat exchange cylinder. A cooling means for cooling the sample liquid is provided, and a sample liquid supply pipe connected to the sample liquid supply tube for supplying the sample liquid in the tank passes through the heat exchange cylinder and opens into the flask. An aspirator that maintains negative pressure inside the cylinder and flask and sucks out the distilled liquid in the heat exchange cylinder is connected to the heat exchange cylinder, and the flask is immersed in heated water in a heating bath. A light emitter for projecting a light beam and a light receiver having a certain light receiving range are arranged so that the light flux reflected from the inner surface of the flask of the light projected from the light emitter enters the light receiving range of the light receiver. , a light receiver detects whether or not the reflected light flux is within the light receiving range and transmits a signal, and when the reflected light flux is outside the light receiving range, the sample liquid is supplied by a signal from the light receiver. A rotary vacuum distillation apparatus in which a solenoid valve connected to a pipe is opened and closed to stop or start supplying the sample liquid into the flask to maintain a constant liquid level in the flask.