JPH09234301A - Vacuum distillation apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To discharge a cooled waste soln. in a moment by forcibly discharging the waste soln. remaining in a distillation part and to enhance the degree of freedom of layout. SOLUTION: This vacuum distillation apparatus equipped with a distillation part 11 heating a solvent to perform vacuum distillation is provided with a discharge means 68 forcibly discharging the waste soln. remaining in the distillation part 11 by a forcible discharge route 67 having a solvent cooling part 46 provided to the midway part thereof.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vacuum distillation apparatus which heats a petroleum solvent or a hydrocarbon solvent that does not have an explosion, and vacuum-distills it to regenerate it into a pure solvent.

[0002]

2. Description of the Related Art Conventionally, as a vacuum distillation apparatus of the above-mentioned example,
For example, there is a device described in JP-A-6-170102. That is, as shown in FIG. 2, a petroleum solvent containing dirt such as oil and fat is stored in a distillation pot 76 through a solvent inlet 71, a filter 72, an economizer 73, a liquid level adjusting unit 74, and an opened / closed valve 75. When vacuum-distilling the petroleum solvent supplied to the distillation pot 76, the opening / closing valve 79 of the communication passage 78 that connects the distillation pot 76 and the storage tank 77 is first closed, and the three-way valve 80 By switching, the still pot 76 and the liquid storage tank 77 are made to communicate with each other through the bypass passage 81, and then the steam is introduced into the heater 86 through the steam inlet 82, the strainer 83, the pressure reducing valve 84, and the opened / closed valve 85. Is circulated, and the petroleum solvent in the distillation pot 76 having a vacuum state of about 30 Torr is heated for vacuum distillation, and the vaporized solvent gas is guided to the cooler 88 via the gas pipe 87 and condensed there. Liquefied pure regeneration solvent Check valve 89, take-out pipe 9
It is a device that takes out through 0.

After the completion of distillation in this conventional vacuum distillation apparatus, in order to discharge the high-temperature waste liquid remaining at the bottom of the distillation pot 76, the open / close valve 79 of the communication passage 78 is opened so that the inside is in a vacuum state beforehand. Reservoir 76 in the storage tank 77
The drainage that naturally flows down from the cooling water inlet 91,
Strainer 92, open / close valve 93, cooling container 9
4. The high-temperature drainage liquid is rapidly cooled by the cooling water flowing through the cooling water passage 95 to the cooling jacket 96 (water jacket), and if the inside of the liquid storage tank 77 remains in a vacuum state, the drainage outlet under the atmospheric pressure. Since the drainage does not flow down to 98, the three-way valve 80 is once communicated with the atmosphere introduction side to establish the normal pressure in the liquid storage tank 77, and the opening / closing valve 97 at the bottom of the tank 77 is opened so that the drainage outlet 98 Drain the drained liquid after cooling.

However, in this conventional apparatus, the distillation still 7
When the drainage liquid in 6 is transferred into the liquid storage tank 77, the drainage liquid is transferred only by natural flow. Therefore, it takes time for the drainage liquid to flow down, and the position of the liquid storage tank 77 is arranged in the distillation pot 76. There is a problem that it is restricted to the lower part and the degree of freedom of layout is impaired. Further, since the drainage is temporarily stocked in the above-mentioned storage tank 77 and the outside air is once introduced into the storage tank 77 from the vacuum state by switching the three-way valve 80, the drainage is discharged. There is also a problem that the discharge process also takes time.

[0005]

According to the first aspect of the present invention, by forcibly discharging the waste liquid remaining in the distillation section, the cooled waste liquid can be discharged instantaneously.
Another object of the present invention is to provide a vacuum distillation apparatus capable of improving the layout flexibility.

According to a second aspect of the present invention, in addition to the object of the first aspect of the invention, the drainage remaining in the distillation section is sucked and discharged by the negative pressure acting on the secondary side of the ejector. In this way, the vacuum inside the distillation section can be improved by effectively utilizing the negative pressure used for sucking the drainage, and after the drainage is discharged from the distillation section, solvent distillation can be restarted without a time lag. An object of the present invention is to provide a vacuum distillation apparatus that can be used.

[0007]

The invention according to claim 1 of the present invention is a vacuum distillation apparatus comprising a distillation section for heating a solvent to perform vacuum distillation, wherein the waste liquid remaining in the distillation section is The vacuum distillation apparatus is characterized in that it is provided with a discharging means for forcibly discharging through a forced discharge path in which a solvent cooling section is provided midway.

According to a second aspect of the present invention, in addition to the configuration of the first aspect of the invention, the discharging means is a circulation for forcibly circulating the solvent in the solvent cooling section through a pump and an ejector main path. And a drainage discharge passage connected between the secondary inlet of the ejector and the drainage residual portion of the distillation section.

[0009]

According to the invention described in claim 1 of the present invention, the above-mentioned distillation section heats the solvent for vacuum distillation, and the above-mentioned discharging means removes the waste liquid remaining in the distillation section by vacuum distillation. , Forced discharge through the forced discharge route with a solvent cooling unit interposed in the middle. In this way, since the drainage remaining in the distillation section is forcibly discharged, there is an effect that the drainage cooled in the solvent cooling section can be instantaneously discharged, and in addition, since it is a forced discharge configuration, The arrangement position of the solvent cooling unit is not limited to the lower part of the distillation unit, and there is an effect that the degree of freedom of layout can be improved.

According to the second aspect of the present invention,
In addition to the effects of the invention described in the above claims, when the solvent in the solvent cooling unit is forcedly circulated in a circulation path having a pump and an ejector, a negative pressure is generated at the secondary inlet of the ejector, and the distillation unit The drainage in the drainage residual portion can be sucked from the secondary inlet through the drainage outlet and discharged through the solvent cooling unit. In this way, the negative pressure acting on the secondary side of the ejector sucks and discharges the waste liquid remaining in the distillation unit, and thus the negative pressure used for sucking the waste liquid is effectively used to reduce the degree of vacuum inside the distillation unit. Can be improved, and as a result,
There is an effect that solvent distillation can be restarted without a time lag after the discharge of the waste liquid from the distillation section.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below in detail with reference to the drawings. The drawing shows a vacuum distillation apparatus that vacuum-distills petroleum-based solvents and hydrocarbon-based solvents that do not have explosive properties. In FIG. 1, this vacuum distillation apparatus is a distillation pot 11 as a distillation section that heats the solvent to perform vacuum distillation. A solvent supply path 13 is connected to the solvent inlet port 12 formed in the lower area of the distillation pot 11.

The solvent supply passage 13 has an inlet 14 for the solvent containing dirt such as oil and fat, a filter 15, a solvent passage 17 meandering in the heat exchanger 16, a liquid level adjusting section 18, and an opening / closing valve 19.
And the above-mentioned solvent is supplied to the still pot 11.

Further, the solvent heating means 2 is provided in the distillation pot 11 described above.
0 is arranged. The solvent heating means 20 has a heater 21 installed therein to store oil as a heating medium.
An oil tank 22 for heating to about 150 ° C., an oil pump 23, a heater 24 located in the distillation pot 11,
It has an oil line 25 that circulates and connects each of these elements 22, 23, and 24, and heats the solvent in the distillation pot 11.

Further, a tubular vaporized solvent line 26 for guiding the vaporized solvent (solvent gas) to the upper portion of the heat exchanger 16 is connected to the upper portion of the distillation pot 11 described above. The lower inner region of the heat exchanger 16 is set in a condenser 30 by a cooling water passage 29 that meanders from the cooling water inlet 27 to the heat exchanger chamber 28, and the condenser 30 is configured to condense and liquefy the vaporized solvent. Here, from the above-mentioned cooling water inlet 27, cooling water (cooling medium) having a predetermined temperature, for example, about 20 ° C.
Is supplied.

On the other hand, a filter 33 having an openable / closable or removable lid member 32 for replacing the filter element 31 is provided on the upper portion, and a pump 37 and an ejector 38 are provided between the upper and lower ports 35, 36 of the filter housing 34. The circulation circuit 39 is connected. The ejector 38 described above
Is a drive flow (primary flow) inlet and a mixing flow outlet connected to the above-mentioned circulation path 39. The solvent in the filter housing 34 is discharged by the pump 37 from the ejector main path (from the drive flow inlet to the mixing flow outlet). A negative pressure is formed at the secondary inlet 40 of the ejector 38 by high-speed circulation in the route (to reach).

The condenser 3 in the above heat exchanger 16
The regenerant outlet 41 of 0 and the secondary inlet 40 are connected by a solvent line 43 in which a check valve 42 is provided.
By the action of the ejector 38 described above, a vacuum degree of about 750 Torr is urged in the distiller 11 described above, and the vaporized and condensed liquefied regenerant liquid is filtered through the secondary inlet 40 and the mixed outlet of the ejector 38. It is configured to be introduced into.

The outlet port 44 of the filter 33 is connected to a regenerated solvent take-out line 45. By the way, a cushion tank 46 having a substantially blind tank structure is provided as a solvent cooling unit, and a meandering water passage 47 connected to the secondary side of the cooling water passage 29 is provided inside the cushion tank 46. The solvent in the same tank 46 is cooled by the cooling water (cooling medium) flowing from the cooling water outlet line 47 to the cooling water outlet line 48 (40 to 50
It is configured to be cooled to ℃).

A circulation path 53, in which a pump 51 and an ejector 52 are provided, is connected between the two ports 49 and 50 of the cushion tank 46. The ejector 52 described above
Is a drive flow (primary flow) inlet and a mixed flow outlet connected to the above-mentioned circulation path 53, like the ejector 38.
A negative pressure is formed in the secondary inlet 54 of the ejector 52 by causing the solvent in the cushion tank 46 to flow at a high speed through the ejector main path (the path from the drive inlet to the mixed outlet) by the pump 51 described above.

An on-off valve 56 and a check valve 57 are interposed between the communication port 55 communicating with the residual liquid portion of the distillation still 11 (the inner bottom of the same) and the above-mentioned secondary inlet 54. It is connected by a drainage discharge line 58 as a drainage discharge path provided, and by the action of the ejector 52 described above, a negative pressure of the drainage of about 100 ° C. is sucked from the distillation pot 11 after distillation, and this negative pressure is also reduced. It is configured so that the degree of vacuum in the distillation pot 11 can be further improved by effectively utilizing it.

Further, the cooling drainage outlet 59 of the cushion tank 46 described above is connected to a drainage line 61 provided in the drainage tank 60. In FIG. 1, 62 and 63 are pressure gauges (vacuum gauges) for visually confirming the degree of vacuum, 64 is a line for supplying a solvent to the cushion tank 46 at the time of starting the apparatus, 65 is an opening / closing valve, and 66 is an air vent. It is an on-off valve.

Here, each of the above-mentioned elements 55, 56, 58,
57, 54, 52, 50, 59, 61 constitute a forced discharge path 67 for forcibly discharging the drained liquid, and the forced discharge path 67 and the above-mentioned elements 46, 49, 51, 53, 52 discharge the drained liquid. The discharge means 68 for cooling and forcibly discharging is configured. In addition, the opening / closing valve 6 for the air vent when the device is started.
6 and the opening / closing valve 65 of the line 64 are opened, and the filter 33
A solvent is previously supplied into the cushion tank 46 from the side through the line 64, and this solvent is used as a driving fluid for forced discharge.

The illustrated embodiment is constructed as described above, and its operation will be described below. In order to supply the solvent into the distillation pot 11, a petroleum solvent containing a stain such as oil and fat and a hydrocarbon solvent are introduced into the inlet 14, the filter 15, the solvent passage 17 in the heat exchanger 16, the liquid level adjusting unit 18, and the opening. The solvent is supplied from the solvent inlet port 12 into the distillation pot 11 via the on-off valve 19 that is valved in this order.

In order to vacuum-distill the solvent in the distilling vessel 11 described above, a negative pressure is generated at the secondary inlet 40 of the ejector 38 by driving the pump 37, and this negative pressure causes the interior of the distilling vessel 11 to have a pressure of about 750 Torr. The degree of vacuum is set to 130 to 1 in the heater 24 by driving the oil pump 23 of the solvent heating means 20.
When the oil of about 50 ° C. is circulated and supplied, the solvent in the distillation pot 11 is vacuum distilled and vaporized. The on-off valve 56 is closed during distillation.

The vaporized solvent (solvent gas) is introduced into the heat exchanger chamber 28 through the vaporized solvent line 26, and then condensed and liquefied by the condenser 30, and the condensed and liquefied regenerated solvent liquid is supplied to the solvent line 43, After being sucked to the secondary inlet 40 of the ejector 38 by a negative pressure via the check valve 42, it is guided into the filter 33 from the mixed outlet of the ejector 38. The regenerated solvent in the filter 33 is taken out from the regenerated solvent take-out line 45. Needless to say, an opening / closing valve may be provided in the reclaimed solvent removal line 45, if necessary.

Due to the above-mentioned vacuum distillation, the inner bottom of the distillation pot 11 is drained at about 100 ° C. (solvent liquid containing dirt such as oil and fat).
Remain. To discharge this drainage to the drainage tank 60, the on-off valve 56 is opened and the circulation path 53 is opened.
When a negative pressure is generated in the secondary inflow port 54 of the ejector 52 by driving the pump 51 installed in the distiller 11, the drainage liquid in the distillation pot 11 passes through the open / close valve 56 and the check valve 57 to the ejector 52. After the negative pressure is forcibly sucked into the next inlet 54, the cushion tank 46 (this tank 46 does not temporarily store the drainage but passes the drainage while cooling it) from the mixed outlet of the ejector 52. Inside), where it is heat-exchanged with cooling water or the like and cooled to, for example, about 40 to 50 ° C. and immediately discharged to the drainage tank 60 via the cooling drainage outlet 59 and drainage line 61. To be done. Further, at the time of discharging the above-described drainage, the degree of vacuum in the distillation pot 11 can be improved by the negative pressure formed at the secondary inlet 54 of the ejector 52.

The pumps 37 and 51 may be configured to be driven by their own drive motors, or the two pumps 37 and 51 may be driven by one common drive motor. You may.

In summary, the above-mentioned distillation section (distillation pot 11)
(See reference) is a solvent (petroleum-based solvent or hydrocarbon-based solvent that does not have explosive properties) heated and vacuum-distilled, and the above-mentioned discharging means 68 is used.
Is a forced discharge path 67 in which a solvent cooling unit (see a cushion tank 46 having a drainage cooling function) is provided in the middle of the drainage of about 100 ° C. that remains in the distillation unit (see distillation pot 11) by vacuum distillation. Cool to 40-50 ° C and force discharge. That is, both the discharge process of transferring the drainage remaining on the inner bottom of the distillation pot 11 to the cushion tank 46 and the discharge process of discharging the drainage cooled in the cushion tank 46 to the drainage tank 60 are instantaneously performed. Can be executed.

As described above, since the waste liquid remaining in the above-mentioned distillation section (see distillation pot 11) is forcibly discharged, the waste liquid cooled in the solvent cooling section (see cushion tank 46) is instantaneously discharged. In addition, since the forced discharge structure is provided, the position where the solvent cooling unit (see the cushion tank 46) is arranged is not limited to the lower portion of the distillation unit (see the distillation pot 11). , This cushion tank 4
6 can be provided on the side of the distillation pot 11, which has the effect of achieving an improvement in the degree of freedom in the layout of the components of the apparatus. The cushion tank 46 described above
When arranging in the lower part of the still pot 11, the drainage can be discharged more efficiently by using the forced negative pressure suction force and gravity together.

Further, when the solvent in the above-mentioned solvent cooling section (see cushion tank 46) is forcedly circulated to the circulator passage 53 (forced circulation passage) having the pump 51 and the ejector 52, the secondary inlet of this ejector 52. Negative pressure is generated in 54, and the waste liquid in the waste liquid remaining portion of the distillation unit (see distillation pot 11) is discharged from the secondary inlet port 54 of the ejector 52 through the waste liquid discharge passage (see waste liquid discharge line 58). It can be sucked and discharged through the solvent cooling unit (see the cushion tank 46).

As described above, since the negative pressure acting on the secondary side of the ejector 52 (see the secondary inlet 54) forces the drainage remaining in the distillation section (see the distillation pot 11) to be sucked out forcibly. By effectively utilizing the negative pressure used for sucking the waste liquid, the degree of vacuum inside the distillation section (see distillation pot 11) can be further improved, and as a result, the vacuum from the distillation section (see distillation pot 11) can be improved. After the drainage, the solvent distillation can be restarted without a time lag.

If oil is used as the heating medium of the solvent heating means 20, a higher temperature can be secured as compared with the structure using steam, so that the distillation efficiency (heating efficiency) can be improved. However, it goes without saying that the heating medium may be the above steam.

In the correspondence between the structure of the present invention and the above-described embodiment, the distillation section of the present invention corresponds to the distillation pot 11 of the embodiment, and hereinafter, the solvent cooling section corresponds to the cushion tank 46. The main ejector path corresponds to the path from the drive inlet of the ejector 52 to the mixed outlet, and the drainage discharge path corresponds to the drainage discharge line 58. However, the present invention is only the configuration of the above-described embodiment. It is not limited to.

[Brief description of drawings]

FIG. 1 is a system diagram showing a vacuum distillation apparatus of the present invention.

FIG. 2 is a system diagram showing a conventional vacuum distillation apparatus.

[Explanation of symbols]

 11 ... Distiller (distillation part) 46 ... Cushion tank (solvent cooling part) 51 ... Pump 52 ... Ejector 53 ... Circulation path 54 ... Secondary inlet 58 ... Drainage discharge line (drainage discharge line) 67 ... Forced discharge route 68 ... Ejection means

Claims (2)

[Claims] 1. A vacuum distillation apparatus equipped with a distillation section for heating a solvent to perform vacuum distillation, wherein the waste liquid remaining in the distillation section is forcibly discharged by a solvent cooling section provided midway. A vacuum distillation apparatus equipped with a discharge means for forced discharge. 2. The discharging means is provided between a circulation path for forcibly circulating the solvent in the solvent cooling section via a pump and an ejector main path, a secondary inlet of the ejector and a waste liquid residual section of the distillation section. And a drainage passage connected to the.
The vacuum distillation apparatus described.