JP2004330111A - Vacuum distillation unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vacuum distillation unit whereby a burden concerning maintenance can be alleviated. <P>SOLUTION: A vacuum distillation unit is provided with: a distillation furnace 1 equipped with a heat means K for heating a solution stored to be distilled; a vacuum means 4 for decompressing the inside of the distillation furnace 1 by vacuuming a steam discharge passage 3 connected to the distillation furnace 1; and a condenser 5 for liquefying steam flowing through the steam discharge passage 3. A gas-liquid separation part 30 for separating mist from steam flowing through the steam discharge passage 3 by a specific gravity difference between mist and steam is provided so that the entire body of the part 30 is located above a connection port 1w of the steam discharge passage 3 of the distillation furnace 1 and liquid liquefied from mist separated at the gas-liquid separation part 30 returns to the distillation furnace 1 by the liquid's own weight. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention is a distillation still equipped with a heating means for heating the stored liquid to be distilled,
Suction means for performing a suction action on a steam discharge passage connected to the distillation still to reduce the pressure inside the distillation still,
The present invention relates to a vacuum distillation apparatus provided with a condenser for liquefying steam flowing through the steam discharge passage.
[0002]
[Prior art]
Such a vacuum distillation apparatus is used, for example, for the purpose of reducing the amount of waste liquid waste by distilling and separating water from a waste liquid containing water as a distillate, or for the purpose of distilling and separating a solvent from waste liquid containing a solvent to regenerate the waste liquid. What is used.
Such a vacuum distillation apparatus heats the liquid to be distilled stored in the distillation still by a heating means, and causes the suction means to suction the vapor discharge path connected to the distillation still, thereby causing the liquid to be distilled to be removed. By evaporating the distillation separation target component contained therein, the vapor of the distillation separation target component is passed through a vapor discharge path, and the vapor of the distillation separation target component flowing through the vapor discharge path is liquefied in a condenser. The components to be separated by distillation are separated as a distillate (for example, see Patent Document 1).
[0003]
As shown in FIG. 7, in such a vacuum distillation apparatus, a gas-liquid separation unit 30 for separating mist from steam flowing through the steam discharge path 3 may be provided. Conventionally, the gas-liquid separation unit 30 is provided with a drain outlet 30e for discharging a liquid portion in which the separated mist becomes liquid (hereinafter, sometimes referred to as a separated liquid portion). A drain tank 51 provided below the connection port 1w of the passage 3 for receiving the separated liquid flowing down from the drain discharge port 3e, and a drain recovery path connecting the drain tank 51 and the distillation still 1 52, a drain recovery passage solenoid valve 53 for opening and closing the drain recovery passage 52, and a drain recovery pump 54 for pumping the separated liquid in the drain tank 51 to the distillation still 1 through the drain recovery passage 52. The separated liquid component separated by the gas-liquid separation unit 30 is pumped through drain recovery passage 52 by drain recovery pump 54, it has been configured to return to the still 1.
[0004]
In FIG. 7, K is a heating means for heating the liquid to be distilled stored in the distillation still 1, 4 is a vacuum pump as a suction means for suctioning the steam discharge path 3, and 5 is a steam discharge A condenser 6 for liquefying the vapor flowing through the passage 3 is a buffer tank for storing the distillate condensed in the condenser 5.
[0005]
[Patent Document 1]
JP-A-6-63304
[0006]
[Problems to be solved by the invention]
By the way, in such a vacuum distillation apparatus, the liquid to be distilled stored in the distillation still sometimes foams during the distillation separation operation in which the component to be subjected to distillation and separation is separated from the liquid to be distilled.
However, in the related art, when the liquid to be distilled foams in the still, the bubbles of the liquid to be distilled flow through the steam discharge path by the suction action of the suction means, and are cooled by the condenser in the steam discharge path. To a portion where the distillate flows, such as a portion or a downstream side of the distillate flow direction (hereinafter, may be referred to as a distillate flow portion). It will adhere to the flowing part. When the bubbles of the liquid to be distilled adhere to the distillate flowing portion of the vapor discharge path, the bubbles of the liquid to be distilled are mixed with the distillate and the quality of the distillate is reduced. There is a problem that the discharge path needs to be cleaned, and the burden on maintenance is increased.
[0007]
Incidentally, in order to suppress foaming of the liquid to be distilled, a defoaming agent may be supplied to the still, but the foaming is appropriately suppressed due to the fact that the components of the liquid to be distilled are not constant. Since the required amount of the antifoaming agent is not clear, conventionally, when the antifoaming agent is supplied, there is a problem that the defoaming agent is excessively supplied and the running cost is increased.
[0008]
Conventionally, when a gas-liquid separation unit is provided, as described above, a drain tank for receiving the separated liquid separated by the gas-liquid separation unit is provided, and the separated liquid in the drain tank is collected for drain collection. Since the pump was configured to be pumped back to the distillation still through the drain recovery passage by the pump, the separation liquid separation recovery route for returning the separated liquid separated in the gas-liquid separation unit to the distillation still becomes complicated, There is a problem that the separated liquid collection path is easily clogged with the residue and the like, and the clogging removal operation is required, and the burden on maintenance is increased.
[0009]
The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a vacuum distillation apparatus capable of reducing a burden on maintenance.
[0010]
[Means for Solving the Problems]
[Invention of claim 1]
The vacuum distillation apparatus according to claim 1, a distillation still provided with a heating means for heating the stored liquid to be distilled,
Suction means for performing a suction action on a steam discharge passage connected to the distillation still to reduce the pressure inside the distillation still,
A condenser for liquefying the steam flowing through the steam discharge path,
A gas-liquid separation unit that separates mist from the steam flowing through the steam discharge passage by a specific gravity difference from the steam is entirely located above a connection port of the steam discharge passage in the distillation still and the gas-liquid separation unit It is characterized in that the mist separated in the section is provided in such a manner that a liquid component in a liquid state returns to the distillation still by its own weight.
That is, the mist is separated from the vapor of the component to be separated by the specific gravity difference from the vapor by the gas-liquid separation section, and the separated liquid in which the separated mist becomes liquid returns to the distillation still by its own weight.
That is, the gas-liquid separation unit is provided so that the entirety thereof is located above the connection port of the vapor discharge passage in the distillation still and the separated liquid separated by the gas-liquid separation unit returns to the distillation still by its own weight. As a result, the separated liquid component can be returned to the distillation still through the originally provided vapor discharge path without using a pump, thereby simplifying the separated liquid component recovery path, Can be prevented from being clogged with the residue of the waste.
Therefore, it is possible to prevent clogging of the separated liquid collection path with residues and the like, so that it is possible to reduce the burden of maintenance.
[0011]
[Invention of claim 2]
According to a second aspect of the present invention, there is provided the vacuum distillation apparatus according to the first aspect, which shields the droplets of the to-be-distilled liquid to be scattered due to bumping of the to-be-distilled liquid in the distillation still from being scattered into the gas-liquid separation section. A feature is that a means is provided.
That is, even if the liquid to be distilled is bumped in the distillation still and the droplets of the liquid to be distilled are scattered, the scattered droplets in the gas-liquid separation section are shielded by the shielding means.
That is, the to-be-distilled liquid may be bumped in the still, and when the to-be-distilled liquid is bumped in such a manner, the droplets of the to-be-distilled liquid reach the distillate flowing portion in the vapor discharge path. In addition, since the liquid to be distilled is mixed with the distillate and the quality of the distillate is degraded, it is necessary to clean the steam discharge passage.
Therefore, by providing a shielding means for blocking the droplets of the liquid to be distilled from splashing into the gas-liquid separation section, even if the liquid to be distilled is bumped, the droplets of the liquid to be distilled are discharged in the vapor discharge path. Since it is possible to suppress reaching to the flow-through portion, maintenance related to cleaning of the steam discharge path can be reduced.
Therefore, even if the to-be-distilled liquid is bumped, the maintenance related to the cleaning of the vapor discharge path due to the bumping of the to-be-distilled liquid can be reduced, so that the burden on the maintenance can be further reduced. Became.
[0012]
[Invention of claim 3]
The vacuum distillation apparatus according to claim 3 is the vacuum distillation apparatus according to claim 1 or 2, wherein a distillation-pot-side discharge path portion connecting the distillation pot and the gas-liquid separation unit in the vapor discharge path includes It is characterized in that it is bent so as to shield the splash from splashing to the gas-liquid separation part, and the shielding means is formed at a portion of the distillation tank side discharge passage.
That is, since the portion of the steam discharge passage that connects the distillation still and the gas-liquid separation portion to the distillation still is bent so as to shield the liquid to be distilled from scattering to the gas-liquid separation portion. Even if the to-be-distilled liquid is bumped and the to-be-distilled liquid is scattered, the scattered droplets hit the inner surface of the distillation-pot-side discharge path portion of the vapor discharge path and are prevented from being scattered to the gas-liquid separation section. You.
In other words, since the scattered droplets of the liquid to be distilled have straightness, all or almost all of the droplets of the liquid to be distilled scattered straight from inside the distillation tank reach the gas-liquid separation section. The shielding means can be configured at the distillation pot side discharge passage portion of the steam discharge passage by bending the distillation pot side discharge passage portion of the steam discharge passage so as to hit the inner surface of the side discharge passage portion.
Therefore, since the shielding means can be provided without using a dedicated member, the burden on maintenance can be further reduced while reducing the cost.
[0013]
[Invention of claim 4]
The vacuum distillation apparatus according to claim 4 is the vacuum distillation apparatus according to claim 2 or 3, so as to shield the droplets of the liquid to be distilled from scattering from the vapor inlet of the gas-liquid separation unit into the gas-liquid separation unit. It is characterized in that a baffle is disposed facing the steam inlet, and the baffle constitutes the shielding means.
That is, even if the liquid to be distilled is bumped and splashes of the liquid to be distilled are scattered, the liquid to be distilled is scattered into the gas-liquid separation part by the baffle plate provided in the gas-liquid separation part so as to face the vapor inlet. Is shielded from doing so.
That is, as the shielding means, the baffle plate is disposed in the gas-liquid separation part in a state facing the steam inlet, so that the steam flowing through the steam discharge path collides with the baffle plate and is included in the steam. It is possible to prevent the mist of the liquid to be distilled from entering the gas-liquid separation section while weakening the force of the mist and effectively separating the mist.
Then, the steam flowing through the steam discharge passage collides with the baffle plate to reduce the force of the mist contained in the steam and effectively separate the mist. The size of the liquid separation unit can be reduced.
Therefore, the burden on maintenance can be further reduced while reducing the size of the gas-liquid separator.
[0014]
[Invention according to claim 5]
The vacuum distillation apparatus according to claim 5, wherein the distillation still provided with a heating means for heating the stored liquid to be distilled,
Suction means for performing a suction action on a steam discharge passage connected to the distillation still to reduce the pressure inside the distillation still,
A condenser for liquefying the steam flowing through the steam discharge path,
Outside air introduction means for introducing outside air into the steam discharge path,
Foam detection means for detecting a bubble presence state in which bubbles are present in the steam flow direction upstream portion from the outside air introduction point by the outside air introduction means in the distillation still or the steam discharge path,
And a control unit for causing the outside air introduction unit to perform the outside air introduction based on the detection of the bubble presence state by the bubble detection unit.
That is, when the bubble detection means detects the bubble presence state, the outside air introduction means is operated by the control means to introduce outside air, and the bubble detection means in the steam discharge path is located on the downstream side in the steam flow direction from the point where the bubble presence state is detected. Since outside air is introduced from the outside air introduction point and flows through the vapor discharge path, it is possible to suppress bubbles of the liquid to be distilled from reaching the distillate flow section in the vapor discharge path.
In addition, since the bubbles of the liquid to be distilled can be prevented from reaching the distillate flowing portion in the vapor discharge path, maintenance related to cleaning of the vapor discharge path can be reduced.
Therefore, the maintenance related to cleaning of the steam discharge passage can be reduced, so that the burden related to the maintenance can be reduced.
[0015]
[Invention of claim 6]
The vacuum distillation apparatus according to claim 6 is the vacuum distillation apparatus according to claim 5, further comprising a steam discharge path closing unit that closes a portion of the steam discharge path downstream of the outside air introduction point in a steam flow direction,
It is characterized in that the control means is configured to close and operate the steam discharge passage closing means based on the detection of the bubble presence state by the foam detection means.
That is, when the bubble detection means detects the presence of bubbles, the control means closes the steam discharge passage closing means and closes the portion of the steam discharge passage downstream of the outside air introduction point in the steam flow direction. The outside air introduced into the steam discharge path from the outside air introduction point by the introduction means is prevented from flowing toward the distillate flow portion on the condenser side from the outside air introduction point, and flows toward the distillation still.
In other words, by allowing the outside air introduced from the outside air introduction point to the steam discharge path to flow only to the distillation pot side, the bubbles of the liquid to be distilled are further suppressed from reaching the distillate flow section in the steam discharge path. It becomes possible to do.
Therefore, the maintenance related to the cleaning of the steam discharge path can be further reduced, so that the load related to the maintenance can be further reduced.
[0016]
[Invention of claim 7]
The vacuum distillation apparatus according to claim 6 is the vacuum distillation apparatus according to claim 5 or 6, further comprising an antifoaming agent supply unit that supplies an antifoaming agent to the distillation still,
A characteristic configuration in which the control means is configured to operate the antifoaming agent supply means to supply a set amount of the antifoaming agent based on the foam detection means detecting a foam presence state. I do.
That is, when the foam detecting means detects the presence of the foam, the control means operates the antifoaming agent supplying means to supply the defoaming agent in the set amount.
By supplying the set amount of the defoaming agent to the still, the foaming of the liquid to be distilled is suppressed in the distillation separation operation after the defoaming agent is supplied, and the subsequent distillation Foaming can be appropriately suppressed by repeatedly operating the defoaming agent supply means to supply the defoaming agent in the set amount each time the foam detecting state is detected by the foam detecting means in the separation processing operation. As described above, it is possible to supply an appropriate amount of the antifoaming agent without becoming excessive, and it is possible to reduce the running cost as compared with the conventional case where the antifoaming agent is excessively supplied.
Also, by supplying the defoaming agent to the still, the foaming of the liquid to be distilled in the distillation separation process is suppressed, so that the outside air introduction means is operated to introduce the outside air based on the generation of bubbles, and the distillation separation process is performed. Can be eliminated, or the number of times the distillation separation process is interrupted can be reduced, thereby improving the efficiency of the distillation separation process.
Therefore, by reducing the maintenance related to the cleaning of the steam discharge passage, the burden related to the maintenance can be reduced, and the running cost related to the supply of the defoaming agent can be reduced and the efficiency of the distillation separation process can be improved. It became so.
[0017]
[Invention of claim 8]
The vacuum distillation apparatus according to claim 6, wherein the distillation still provided with a heating means for heating the stored solution to be distilled,
Suction means for performing a suction action on a steam discharge passage connected to the distillation still to reduce the pressure inside the distillation still,
A condenser for liquefying the steam flowing through the steam discharge path,
Foam detection means for detecting the presence of foam in the distillation still or the steam discharge path,
Defoaming agent supply means for supplying an antifoaming agent to the distillation still,
Control means for operating the defoaming agent supply means so as to supply a set amount of the antifoaming agent based on detection of the foam presence state by the foam detection means is provided.
That is, when the foam detecting means detects the presence of the foam, the control means operates the antifoaming agent supplying means to supply the defoaming agent in the set amount.
In other words, since the foaming of the liquid to be distilled is suppressed by supplying the set amount of the antifoaming agent to the still, the bubbles of the liquid to be distilled reach the distillate flowing portion in the vapor discharge path. It is also possible to suppress the defoaming agent supply means every time the foam detecting state is detected by the foam detecting means after the set amount of the antifoaming agent is supplied. By repeating the operation to supply the defoaming agent to the set amount, it is possible to suppress the bubbles of the liquid to be distilled from reaching the distillate flowing portion in the vapor discharge path, An appropriate amount of the antifoaming agent can be supplied without becoming excessive so that foaming can be appropriately suppressed.
And, since it becomes possible to supply an appropriate amount of an antifoaming agent so that foaming can be appropriately suppressed, it is possible to reduce the running cost as compared with the conventional case where an antifoaming agent is excessively supplied. Will be possible.
Therefore, by reducing the maintenance related to the cleaning of the steam discharge passage, the burden related to the maintenance can be reduced, and the running cost related to the supply of the antifoaming agent can be reduced. became.
[0018]
BEST MODE FOR CARRYING OUT THE INVENTION
[First Embodiment]
Hereinafter, a first embodiment of the present invention will be described with reference to the drawings.
As shown in FIG. 1, the vacuum distillation apparatus adjusts the storage level of the liquid to be distilled L in the distillation still 1 provided with a heating means K for heating the liquid to be distilled L stored therein. Vacuum pump 4 serving as a suction means for reducing the pressure inside distillation still 1 by suction acting on storage level adjuster 2 and steam discharge passage 3 connected to distillation still 1, and mist from steam flowing through steam discharge passage 3 Gas-liquid separation unit 30 that separates the air by the specific gravity difference from steam, outside air introduction means I for introducing outside air to the steam discharge path 3, defoaming agent supply means D for supplying the defoaming agent to the distillation still 1, and steam discharge path 3. A condenser 5 for liquefying the steam flowing therethrough by cooling with cooling water, a buffer tank 6 for storing the distillate condensed in the condenser 5, and control as a control means for controlling various kinds of vacuum distillation apparatuses It comprises a part 7 and the like.
[0019]
Hereinafter, each part of the vacuum distillation apparatus will be described.
As shown in FIGS. 1 and 2, the distillation still 1 comprises a bottomed cylindrical pot body 1 m and a pot lid 1 c for closing an opening of the pot main body 1 m. A heat medium flowing heating jacket 1j is formed so as to surround the outer periphery of the pot main body 1m, and a guide 1g for guiding the heating medium in a spiral manner through the heating medium flowing heating jacket 1j. Is provided. The distillation still 1 is arranged in a vertical position in which the axis of the still main body 1m is oriented vertically.
In the state where the distillation still 1 is arranged as described above, a heating steam supply port 1i is formed at a position located at the upper end of the heating jacket 1j for flowing the heat medium, and a drain discharge port is formed at a position located at the bottom. An outlet 1e is formed.
[0020]
As shown in FIGS. 1 and 2, as the heating means K, a heating heater H installed in a state of being inserted into the distillation still 1 and the above-described heating jacket 1j for flowing the heat medium are configured. .
The heater H is described below. As shown in FIGS. 3 to 5, the heater H is a bottomed cylindrical ceramic body 15 having a closed end, and a heating medium inserted therein. A return pipe 16 is provided so that steam for heating is supplied to the inside from the base end side of the ceramic body 15 and discharged outside through the heat medium return pipe 16. The ceramic body 15 is made of a mixture of silicon and silicon carbide, and is formed in a straight cylindrical shape having a straight axis and a substantially constant diameter in the axial direction.
[0021]
A heater lid 17 for closing the base end opening of the ceramic body 15 is provided, and the heat medium return pipe 16 is supported by the heater lid 17 so as to penetrate the heater lid 17. 17, a heating steam supply unit 18 communicating with the inside of the ceramic body 15 when the heater lid 17 is attached to the ceramic body 15, and a heating steam supply unit 18 communicating with the base end of the heat medium return pipe 16. And a steam discharge section 19 for use.
The heater lid 17 is provided with a plurality of nut members 20 engaged with a flange provided at a base opening edge of the ceramic body 15 and a plurality of nuts provided in a state inserted through the heater lid 17. A plurality of bolts 21 are separately screwed into the member 20 and attached to the base opening of the ceramic body 15 with a packing 29 made of Teflon or the like interposed therebetween.
[0022]
With the heater lid 17 attached to the base end opening of the ceramic body 15, the heat medium return pipe 16 is configured to extend to near the distal end in the ceramic body 15. A helical blade 22 is attached to the outer peripheral portion of the portion inserted into the ceramic body 15 in a spiral shape over substantially the entire length thereof. Then, the heating steam supplied to the base end side of the ceramic body 15 is spirally passed through the spiral blade body 22 to the tip inside the ceramic body 15, and then the heating medium By allowing the steam to flow into the distal end opening of the return pipe 16, the steam for heating is allowed to flow over substantially the entire length of the ceramic body 15, so that the inside of the distillation still 1 can be efficiently heated. It is.
[0023]
As shown in FIGS. 1 and 2, the heater H configured as described above is supported by the pot lid 1 c in a state where the ceramic body 15 penetrates the pot lid 1 c of the distillation pot 1. When the pot lid 1c supporting the heater H is attached to the pot main body 1m as described above, the heater H is attached to the distillation pot 1 in a state where the ceramic body 15 is coaxially inserted into the pot. Will be prepared.
[0024]
As shown in FIG. 1, a heating steam supply passage 24 to which heating steam is supplied from a heating steam supply source 23 such as a boiler is connected to a heating steam supply section 18 of the heater H and a heating medium for heating medium flowing. A heating steam supply port 1i of the jacket 1j is connected in parallel, and a heating steam discharge unit 19 of the heater H is connected to a heating steam supply source 23 through a heating steam return path 25 to supply heating steam. It is configured to flow through the heater H and the heating jacket 1j for flowing the heating medium to heat the inside of the distillation still 1. The heating steam supply passage 24 is provided with a heating steam solenoid valve V4 for interrupting the supply of heating steam to the heating heater H and the heating medium flowing heating jacket 1j.
Incidentally, the ratio of the flow rate at which the heating steam flows through the heater H to the flow rate at which the heating steam flows through the heating medium flowing heating jacket 1j is about 3: 1.
[0025]
As shown in FIG. 1, a processing liquid supply passage 10 is connected to an end of the steam discharge passage 3 on the side of the distillation still 1, and the inside of the distillation still 1 is suctioned by being depressurized by the vacuum pump 4. The processing liquid L stored in the processing liquid storage layer 11 is supplied to the distillation still 1 through the processing liquid supply path 10 and the vapor discharge path 3 by force. The supply path 10 is provided with a treatment liquid supply solenoid valve V2 for interrupting the supply of the liquid to be distilled L to the still 1.
The bottom of the still 1 is connected to a bottom discharge 8, and the bottom 8 has a bottom discharge pump 9 for forcibly discharging the bottom from the bottom 1, and a bottom discharge pump 9. An electromagnetic valve for discharging residual liquid V1 for opening and closing the passage 8 is provided.
[0026]
The storage level adjuster 2 communicates a bottom portion thereof with a bottom portion of the distillation still 1 through a liquid phase communication passage 26 and a gas phase portion of the upper portion through a gas phase communication portion 27. The storage level adjuster 2 is provided with a processing liquid storage level sensor 2 s for detecting the storage level of the liquid to be distilled L in the storage level adjuster 2. As will be described later in detail, the control unit 7 controls the opening / closing of the processing liquid supply electromagnetic valve V2 based on the detection information of the processing liquid storage level sensor 2s, thereby controlling the processing liquid L to be stored in the distillation still 1. The liquid level Ls is configured to be maintained within a set liquid level height range.
[0027]
As shown in FIG. 1, an antifoaming agent supply means D connects an antifoaming agent tank 40 for storing an antifoaming agent such as a silicon-based antifoaming agent, and the antifoaming agent tank 40 to the distillation still 1. An antifoaming agent supply passage 41, an antifoaming agent supply electromagnetic valve V5 for opening and closing the antifoaming agent supply passage 41, and the defoaming agent in the antifoaming agent tank 40 through the antifoaming agent supply passage 41 to the distillation still 1. A defoamer supply pump 42 for feeding under pressure is provided.
Then, as will be described in detail later, the control unit 7 opens the defoaming agent supply solenoid valve V5 during the set time for defoaming agent supply, and switches the defoaming agent supply pump 42 on. It is configured to operate at a set rotation speed to supply a set amount of the defoamer to the distillation still 1. As the set amount, assuming a plurality of types of liquid to be distilled having different components, the amount is smaller than the amount of the antifoaming agent considered to be the minimum necessary to prevent foaming of the plurality of types of liquid to be distilled. The antifoaming agent supply pump 42 is set to an amount, for example, about 1/2 or 1/3 of the minimum necessary amount. And the time is set so that the set amount of the antifoaming agent can be supplied.
[0028]
As shown in FIG. 1, the steam discharge passage 3 is connected to the distillation still 1 at a connection port 1w formed at the upper end portion of the distillation still 1. The gas-liquid separation unit 30, the condenser 5, and the buffer tank 6 are provided in this order from the upstream side in the steam flow direction, a portion between the condenser 5 and the buffer tank 6 in the steam discharge path 3, and a buffer. A check valve 12 is provided at each of the locations downstream of the tank 6 in the steam flow direction, and the outside air introduction means I is provided at a position between the gas-liquid separation unit 30 and the condenser 5 in the steam discharge path 3. It is provided so that outside air is introduced into the steam discharge path 3.
[0029]
As shown in FIGS. 1 and 2, the gas-liquid separation unit 30 is entirely located above the connection port 1 w of the steam discharge path 3 in the distillation still 1 and separated by the gas-liquid separation unit 30. The mist is provided so that a liquid portion of the mist is returned to the distillation still 1 by its own weight.
Further, a shielding means S is provided to shield the droplets of the liquid to be distilled L that are scattered due to bumping of the liquid to be distilled L in the distillation still 1 from scattering into the gas-liquid separation section 30.
[0030]
Next, based on FIG. 2, the gas-liquid separation unit 30, the installation form of the gas-liquid separation unit 30, and the shielding means S will be described.
The gas-liquid separation unit 30 is formed in a substantially cylindrical box shape whose axial direction is oriented vertically, and steam flows in from a circular steam inlet 30i at the bottom and from a circular steam outlet 30e at the top. It is provided in the middle of the steam discharge path 3 so that the steam flows out. A filter 31 is provided in the gas-liquid separation unit 30, and an inspection window 30 m is provided on a side wall of the gas-liquid separation unit 30, which is air-tightly shielded with transparent glass.
[0031]
The distillation pot side discharge path portion 3u connecting the distillation still 1 and the gas-liquid separation unit 30 in the steam discharge path 3 is formed to be bent into an arc having a central angle of approximately 90 °, and the arc-shaped distillation pot side discharge path. The portion 3u is positioned such that, in plan view, the axis of the distillation pot side discharge path section 3u is along the radial direction of the distillation pot 1 and the opening at the tip of the distillation pot side discharge path section 3u faces upward in the vertical direction. The end is provided so as to communicate with the connection port 1 w of the distillation still 1.
The vapor inlet 30i of the gas-liquid separation unit 30 is connected to the distal end of the distillation pot side discharge passage portion 3u with the axial direction thereof pointing in the vertical direction. It is provided in a state where it is supported.
Therefore, the liquid component in which the mist separated in the gas-liquid separation unit 30 has become liquid can be returned to the distillation still 1 by passing through the distillation-stand-side discharge path portion 3u.
[0032]
The droplets of the liquid to be distilled L which are scattered due to bumping of the liquid to be distilled L in the distillation still 1 have straightness, and as shown in FIG. The inner diameter of the discharge path portion 3u (that is, the diameter of the connection port 1w of the still 1) and the bent form are such that all or almost all of the droplets of the liquid to be distilled L scattered straight from inside the still 1 are subjected to gas-liquid separation. The shielding means S is configured so as to hit the inner surface of the distillation pot side discharge passage portion 3u before reaching the steam inlet 30i of the section 30 and the distillation pot side discharge passage portion 3u of the steam discharge passage 3.
In other words, the inner diameter and the bent form of the distillation pot side discharge path portion 3u are defined by the imaginary straight line P so as to pass through the connection port 1w from each part of the liquid level Ls of the liquid to be distilled L in the set liquid level height range. There is no liquid surface portion of the to-be-distilled liquid L that can be pulled so as to pass through the vapor inlet 30i of the gas-liquid separation section 30 when pulled, or the range is set as narrow as possible.
[0033]
In setting the diameter and the bending shape of the distillation pot side discharge passage portion 3u as described above, when bumping occurs in the liquid L to be distilled in the distillation pot 1, an abrupt change in the distillation pot 1 occurs. In order to sufficiently reduce the increase in pressure, the inner diameter of the distillation channel side discharge passage portion 3u is set to be as large as possible.
Since the inner diameter of the distillation pot side discharge passage portion 3u is set to be large enough to sufficiently reduce a sudden pressure increase in the distillation pot 1 when bumping occurs, bumping occurs in the distillation pot 1. In this case, it is possible to prevent the liquid to be distilled L from overflowing into the distillation pot side discharge passage portion 3u of the steam discharge passage 3, so that the set liquid level height range can be set high. Become.
Since the set liquid level height range can be set high, the heat transfer area for heating the to-be-distilled liquid L stored in the distillation still 1 can be increased, and the heating efficiency can be increased. Therefore, the size of the distillation still 1 can be reduced.
[0034]
Further, a disc-shaped disk having a diameter larger than the diameter of the steam inlet 30i is provided so as to shield the droplets of the liquid to be distilled L from scattering from the vapor inlet 30i of the gas-liquid separator 30 into the gas-liquid separator 30. The baffle plate 32 is disposed concentrically with the steam inlet 30i at a distance from the steam inlet 30i and opposed to the steam inlet 30i by using a baffle plate support rod 33, and the baffle plate 32 shields the baffle plate 32. Means S are constituted.
In other words, in providing the baffle plate 32, as shown in FIG. 2, when the virtual straight line P is drawn as described above, the liquid to be distilled L which can be drawn so as to pass through the vapor inlet 30i of the gas-liquid separator 30. Is provided so as to intersect the baffle plate 32 with a virtual straight line P drawn from the liquid surface portion so as to pass through the vapor inlet 30i. Is prevented from being scattered from the vapor inlet 30i of the gas-liquid separation unit 30 into the gas-liquid separation unit 30.
[0035]
As shown in FIGS. 1 and 2, a pair of sensor mounting holes which are hermetically shielded by transparent glass in a state where they are diametrically opposed to each other are formed in a portion 3 u of the steam discharge path 3 on the distillation pot side. A transmission-type bubble detection optical sensor 34 including a light-emitting portion 34e and a light-receiving portion 34r is provided using the pair of sensor mounting holes.
That is, the liquid to be distilled L foams in the still 1 and the bubbles of the liquid to be distilled L are set between the light emitting section 34e and the light receiving section 34r in the still path 3u. When flowing into the detection area of the bubble detecting optical sensor 34, the light receiving unit 34r decreases the amount of received light to detect a bubble presence state. Thus, a bubble detecting means for detecting a bubble existing state in which bubbles are present in a portion of the steam discharge path 3 upstream of the outside air introduction means by the outside air introduction means I in the steam flow direction.
Further, the distillation path on the distillation pot side 3u of the steam discharge path 3 is located upstream of the detection area of the bubble detection optical sensor 34 in the direction of flow of the vapor, and is airtightly shielded by transparent glass. An inspection window 3m is provided.
[0036]
As shown in FIGS. 1 and 2, the outside air introduction means I includes an outside air introduction path 35 branched from a location between the gas-liquid separation unit 30 and the condenser 5 in the steam discharge path 3, and the outside air introduction path. An external air introduction solenoid valve V6 for opening and closing the passage 35 is provided.
Further, the steam discharge passage 3 is located downstream of the connection point of the outside air introduction passage 35, that is, the outside air introduction point by the outside air introduction means I, and functions as a steam discharge passage closing means. A steam discharge passage solenoid valve V7 is provided.
As will be described later in detail, the control section 7 closes the steam discharge passage solenoid valve V7 and opens the outside air introduction solenoid valve V6, thereby allowing outside air to pass through the outside air introduction passage 35 to the steam discharge passage 3. While preventing the introduced outside air from flowing toward the condenser 5 and flowing only toward the distillation still 1. That is, by opening the outside air introduction solenoid valve V6, the outside air introduction means I is operated to introduce outside air.
[0037]
As shown in FIG. 1, the buffer tank 6 is configured to store a distillate in a state where a vapor phase is formed in the upper part, and the vapor discharge path 3 is connected to the vapor phase of the buffer tank 6. I have.
A distillate discharge path 13 is connected to the lower end of the buffer tank 6. The distillate discharge path 13 has a distillate discharge pump 14 for discharging distillate from the buffer tank 6, and a distillate discharge pump 13. A distillate discharge solenoid valve V3 for opening and closing the liquid discharge passage 13 is provided.
The buffer tank 6 is provided with a distillate level sensor 6s for detecting the storage level of the distillate stored inside.
[0038]
Next, the control operation of the control unit 7 will be described.
When an operation start command is issued from the operation panel 28, the control unit 7 opens the treatment liquid supply solenoid valve V2, the heating steam solenoid valve V4, and the steam discharge passage solenoid valve V7, and discharges residual liquid. Vacuum valve V1, the defoaming agent supply electromagnetic valve V5, and the outside air introduction electromagnetic valve V6 are closed, and the residual liquid discharge pump 9 and the defoamer supply pump 42 are stopped. 4 is operated to start the distillation separation processing operation.
That is, the inside of the distillation still 1 is decompressed, and the to-be-distilled processing liquid L is supplied to the distillation still 1 through the processing liquid supply path 10 by the suction force by the reduced pressure so that the storage level is within the set range. The steam for heating is passed through the heater H and the heating jacket 1j for flowing the heat medium, and the liquid L to be distilled in the distillation still 1 is heated. Then, the pressure in the distillation still 1 is reduced and the liquid L to be distilled is heated, so that the component to be distilled and separated is evaporated from the liquid to be distilled L, and the vapor of the component to be distilled and separated is vaporized. The mist is removed by the liquid separation unit 30 and flows through the steam discharge passage 3. The vapor of the component to be distilled and separated flowing through the steam discharge passage 3 is cooled by the cooling water in the condenser 5 and liquefied. The liquefied distillate is stored in the buffer tank 6, and the component to be subjected to distillation separation is distilled and recovered from the liquid to be distilled L.
The liquid component in which the mist separated in the gas-liquid separation unit 30 has become liquid returns to the distillation still 1 via the distillation-side discharge passage portion 3u.
Further, even if bumping occurs in the liquid to be distilled L in the still 1, the splash of the liquid to be distilled L that is scattered is shielded by the inner surface of the distillation path 3u and the baffle plate 32. It is prevented from being scattered downstream of the gas-liquid separation section 30 in the steam discharge path 3 in the steam flow direction.
[0039]
During the above-mentioned distillation separation processing operation, the liquid level Ls of the liquid to be distilled L in the storage level adjuster 2 is adjusted to the set liquid level height based on the detection information of the processing liquid storage level sensor 2s of the storage level adjuster 2. The opening and closing of the processing liquid supply solenoid valve V2 is controlled so as to maintain the range. Since the liquid level Ls of the liquid L to be distilled in the still 1 is the same as the liquid level Ls of the liquid L to be distilled in the storage level adjuster 2, the liquid level Ls of the liquid L to be distilled in the still 1 is set. Is maintained within the set liquid level range.
That is, when the liquid level Ls of the liquid L to be distilled becomes lower than the lower limit of the set liquid level height range, the processing liquid supply electromagnetic valve V2 is opened. Then, the liquid L to be distilled is supplied to the distillation still 1 through the processing liquid supply path 10, and the liquid level Ls of the storage level adjuster 2 rises in the same manner as the liquid level Ls of the distillation still 1 rises. When the liquid level Ls of the storage level adjuster 2 reaches the upper limit of the set liquid level height range, the processing liquid supply solenoid valve V2 is closed, and the supply of the liquid L to be distilled to the distillation still 1 is performed. Is stopped.
[0040]
Further, based on the detection information of the distillate level sensor 6s of the buffer tank 6, the opening and closing control of the distillate discharge solenoid valve V3 and the distillate are controlled so that the storage level of the distillate in the buffer tank 6 is maintained within a set range. The start / stop control of the discharge pump 14 is executed.
That is, when the storage level of the buffer tank 6 exceeds the upper limit, the distillate discharge solenoid valve V3 is opened, and the distillate discharge pump 14 is operated to discharge the distillate from the buffer tank 6, When the storage level of the buffer tank 6 reaches the lower limit value with the discharge, the distillate discharge solenoid valve V3 is closed, and the distillate discharge pump 14 is stopped, and the distillation from the buffer tank 6 is stopped. The discharge of the liquid is stopped.
[0041]
During the distillation separation operation, the control unit 7 monitors the detection information of the foam detection optical sensor 34, and every time the foam detection optical sensor 34 detects The external air introduction / defoaming agent supply control in which the distillation separation operation is interrupted, the external air introducing means I is operated to introduce the external air, and the defoaming agent supply means D is operated to supply the defoaming agent in a set amount. Execute.
That is, in the outside air introduction / defoaming agent supply control, the control unit 7 stops the vacuum pump 4, closes the heating steam solenoid valve V4 and the steam discharge passage solenoid valve V7, and then controls the outside air introduction solenoid valve V6. Then, the defoaming agent supply electromagnetic valve V5 is opened and the defoaming agent supply pump 42 is operated. After that, when the defoaming agent supply set time has elapsed, the outside air introduction electromagnetic valve V6 and the defoaming agent supply The solenoid valve V5 is closed and the defoaming agent supply pump 42 is stopped, then the heating steam solenoid valve V4 and the steam discharge passage solenoid valve V7 are opened, and then the vacuum pump 4 is operated. .
[0042]
That is, in the outside air introduction / defoaming agent supply control, the supply of the heating steam to the heating heater H and the heating medium flowing heating jacket 1j is stopped, the heating operation of the heating means K is stopped, and the vacuum pump 4 is stopped. Is stopped and the distillation separation operation is interrupted, outside air is introduced into the steam discharge path 3 through the outside air introduction path 35, and the introduced outside air is caused to flow back through the steam discharge path 3 toward the distillation still 1, whereby steam is removed. The bubbles of the liquid to be distilled L present in the discharge path 3 are pushed back into the still 1 to prevent the bubbles of the liquid to be distilled L from flowing downstream of the gas-liquid separator 30 in the vapor flow direction. In addition, the defoamer is supplied to the distillation still 1 through the defoamer supply path 41 in a set amount.
Each time the bubble detection state is detected by the bubble detection optical sensor 34, the defoaming agent is supplied to the distillation still 1 by a set amount, so that the foaming of the liquid to be distilled L can be appropriately suppressed. An appropriate amount of antifoaming agent can be supplied without becoming excessive.
Further, when the outside air introduction / antifoaming agent supply control is executed, the outside air flows through the filter 31 in the reverse direction, so that the clogging of the filter 31 is also eliminated.
[0043]
When a residual liquid discharge command for discharging the residual liquid remaining in the distillation still 1 is issued, the residual liquid discharge electromagnetic valve V1 is opened and the residual liquid discharge pump 9 is operated. Therefore, the residual liquid is forcibly discharged from the still 1.
Incidentally, the residual liquid discharge command is configured to be artificially instructed by the operation panel 28.
Alternatively, a process end detecting means for detecting a process end corresponding to the end of the distillation separation process is provided, and based on the process end detecting means detecting the process end, the residual liquid discharge command is instructed. It can be configured to be.
By the way, as the processing end detecting means, for example, an operation time setting unit for setting an operation time for performing the distillation separation processing operation is provided, and after the distillation separation processing operation is started, the operation time setting unit is set. It can be configured to detect that the processing end has been reached based on the elapse of the operation time.
[0044]
When an operation stop command is issued from the operation panel 28, the processing liquid supply solenoid valve V2 and the heating steam solenoid valve V4 are closed, and the vacuum pump 4 is stopped when a set time elapses after closing these valves. Then, the distillation separation processing operation is stopped.
[0045]
Incidentally, when the component to be subjected to distillation separation is water, for example, the pressure inside the still 1 is reduced to about 12.7 kPa, and the inside of the still 1 is heated to about 70 ° C.
[0046]
[Second embodiment]
Hereinafter, a second embodiment of the present invention will be described. However, the same components and components having the same operations as those of the first embodiment are denoted by the same reference numerals to avoid redundant description, and description thereof will be omitted. Mainly, a configuration different from the first embodiment will be described.
As shown in FIG. 6, in the second embodiment, the outside air introduction means I and the solenoid valve V7 for the steam discharge passage in the first embodiment are omitted, and the outside air introduction means I and the solenoid valve V7 for the steam discharge passage are omitted. The configuration is the same as that of the first embodiment except that the control operation of the control unit 7 is different in connection with the omission of.
[0047]
Hereinafter, portions of the control operation of the control unit 7 different from those of the first embodiment will be described.
When an operation start command is issued from the operation panel 28, the control unit 7 opens the treatment liquid supply solenoid valve V2 and the heating steam solenoid valve V4, and also performs the residual liquid discharge solenoid valve V1 and the defoaming agent. With the supply electromagnetic valve V5 closed and the residual liquid discharge pump 9 and the defoamer supply pump 42 stopped, the vacuum pump 4 is operated to start the distillation separation processing operation.
[0048]
During the distillation separation operation, the control unit 7 monitors the detection information of the foam detection optical sensor 34, and every time the foam detection optical sensor 34 detects The defoaming agent supply control for operating the defoaming agent supply means D to supply the set amount of the defoaming agent is executed.
That is, in the defoaming agent supply control, the control unit 7 opens and deactivates the defoaming agent supply electromagnetic valve V5 in a state where the operation of the vacuum pump 4 and the open state of the heating steam electromagnetic valve V4 are continued. The foam supply pump 42 is operated, and after that, when the set time for defoamer supply has elapsed, the defoamer supply electromagnetic valve V5 is closed and the defoamer supply pump 42 is stopped.
[0049]
That is, in the defoaming agent supply control, the defoaming agent is supplied to the defoaming agent supply passage 41 while the heating operation of the heating means K and the depressurization of the distillation still 1 by the vacuum pump 4 are continued, and the distillation separation processing operation is continued. And the set amount is supplied to the distillation still 1 through the heater.
Each time the bubble detection state is detected by the bubble detection optical sensor 34, the defoaming agent is supplied to the distillation still 1 by a set amount, so that the foaming of the liquid to be distilled L can be appropriately suppressed. An appropriate amount of antifoaming agent can be supplied without becoming excessive.
[0050]
[Another embodiment]
Next, another embodiment will be described.
(A) An embodiment in which the gas-liquid separation unit 30 is omitted from the configuration in each of the first and second embodiments is also possible.
[0051]
(B) In each of the first and second embodiments, the installation position of the bubble detection optical sensor 34 can be changed.
For example, it may be provided so as to detect the state of the presence of bubbles in the still 1.
Alternatively, it may be provided so as to detect the presence of bubbles above the baffle plate 32 in the gas-liquid separation unit 30, that is, on the downstream side in the vapor flow direction. In this case, even if bumping occurs in the liquid to be distilled L in the still 1, the scattered droplets of the liquid to be distilled L are shielded by the inner surface of the distillation path 3u and the baffle plate 32. Since the glass in the sensor mounting hole can be prevented from being stained, maintenance related to cleaning the glass in the sensor mounting hole can be reduced.
[0052]
(C) The specific configuration of the bubble detection means is not limited to the transmission type bubble detection optical sensor 34 exemplified in each of the above embodiments. For example, the configuration may be a reflection type optical sensor. Good.
[0053]
(D) The distillation pot side discharge path portion 3u of the vapor discharge path 3 is bent so as to shield the droplets of the liquid to be distilled from scattering to the gas-liquid separation unit 30, and the steam discharge path portion 3u In configuring the shielding means S, the bent form is not limited to the form exemplified in each of the above embodiments. For example, it may be bent in a V shape.
[0054]
(E) The still 1 is usually made of a metal such as stainless steel. When an acidic solution to be distilled is to be treated, the inner surface of the still 1 is made of Teflon or the like in order to prevent corrosion of the still 1. Coating with acid resistant material. Therefore, when coating the inner surface of the still 1, the heat transfer performance is reduced by the coating film, so that the heating medium flowing heating jacket 1 j is preferably omitted.
[0055]
(F) The shape of the ceramic main body 15 is not limited to a straight cylindrical shape as exemplified in the above embodiment, and various shapes such as a U-shaped cylindrical shape and a J-shaped cylindrical shape are possible. In order to simplify the shape, a straight cylindrical shape is most preferable.
[0056]
(G) The heating heat medium flowing through the heater H is not limited to steam as exemplified in the above embodiment, and various heat media such as hot water and oil can be used.
(H) The specific configuration of the heating means K is not limited to the heater H using the heating heat medium as a heat source as exemplified in the above embodiment. For example, it can be constituted by an electric heater provided in the still 1 or an electric heater provided so as to perform a heating action from the outside of the still 1.
[Brief description of the drawings]
FIG. 1 is a block diagram showing an overall configuration of a vacuum distillation apparatus according to a first embodiment.
FIG. 2 is a vertical sectional view of a distillation still and a gas-liquid separation unit of the vacuum distillation apparatus according to the first embodiment.
FIG. 3 is a longitudinal sectional view of a heater of the vacuum distillation apparatus according to the first embodiment.
FIG. 4 is a plan view of a heater of the vacuum distillation apparatus according to the first embodiment.
FIG. 5 is a cross-sectional plan view of a heater of the vacuum distillation apparatus according to the first embodiment.
FIG. 6 is a block diagram showing an overall configuration of a vacuum distillation apparatus according to a second embodiment.
FIG. 7 is a block diagram of a conventional vacuum distillation apparatus.
[Explanation of symbols]
1 distillation still
1w connection port
3 Steam discharge path
3u distillation pot side discharge channel
4 Suction means
5 Condenser
7 control means
30 Gas-liquid separation unit
30i steam inlet
32 Baffle
34 Foam detection means
D Antifoaming agent supply means
I Outside air introduction means
K heating means
S Shielding means
V7 Steam discharge path closing means

Claims (8)

A distillation still equipped with a heating means for heating the stored liquid to be distilled,
Suction means for performing a suction action on a steam discharge passage connected to the distillation still to reduce the pressure inside the distillation still,
A condenser for liquefying the steam flowing through the steam discharge path, and
A gas-liquid separation unit that separates mist from the steam flowing through the steam discharge passage by a specific gravity difference from the steam is located entirely above a connection port of the steam discharge passage in the distillation still and the gas-liquid separation A vacuum distillation apparatus provided such that a liquid component in which the mist separated in the section becomes liquid returns to the distillation still by its own weight. The vacuum distillation apparatus according to claim 1, further comprising a shielding unit that shields a droplet of the liquid to be distilled scattered due to bumping of the liquid to be distilled in the distillation still from scattering into the gas-liquid separation unit. A distillation-pot-side discharge path portion connecting the distillation still and the gas-liquid separation unit in the vapor discharge path is bent so as to shield the droplets of the liquid to be distilled from scattering into the gas-liquid separation unit. 3. The vacuum distillation apparatus according to claim 2, wherein said shielding means is formed at a portion of the distillation path on the distillation pot side. A baffle plate is arranged in a state facing the vapor inlet so as to shield the droplets of the liquid to be distilled from scattering from the vapor inlet of the gas-liquid separator into the gas-liquid separator. 4. The vacuum distillation apparatus according to claim 2, wherein said shielding means is constituted by a plate. A distillation still equipped with a heating means for heating the stored liquid to be distilled,
Suction means for performing a suction action on a steam discharge passage connected to the distillation still to reduce the pressure inside the distillation still,
A condenser for liquefying the steam flowing through the steam discharge path, and
Outside air introduction means for introducing outside air into the steam discharge path,
Foam detection means for detecting a bubble presence state in which bubbles are present in the steam flow direction upstream portion from the outside air introduction point by the outside air introduction means in the distillation still or the steam discharge path,
A vacuum distillation apparatus provided with control means for causing the outside air introduction means to perform an outside air introduction operation based on the detection of the presence state of the foam by the foam detection means. Steam discharge path closing means for closing a downstream portion of the steam discharge path in the steam flow direction from the outside air introduction point is provided,
6. The vacuum distillation apparatus according to claim 5, wherein the control unit is configured to close and operate the steam discharge passage closing unit based on the detection of the bubble presence state by the foam detection unit. Defoaming agent supply means for supplying an antifoaming agent to the still is provided,
7. The control means is configured to operate the antifoaming agent supply means to supply a set amount of the antifoaming agent based on the detection of the foam presence state by the foam detecting means. 8. The vacuum distillation apparatus according to claim 1. A distillation still equipped with a heating means for heating the stored liquid to be distilled,
Suction means for performing a suction action on a steam discharge passage connected to the distillation still to reduce the pressure inside the distillation still,
A condenser for liquefying the steam flowing through the steam discharge path, and
Foam detection means for detecting the presence of foam in the distillation still or the steam discharge path,
Defoaming agent supply means for supplying an antifoaming agent to the distillation still,
A vacuum distillation apparatus provided with control means for operating the antifoaming agent supply means to supply a set amount of the antifoaming agent based on detection of the foam presence state by the foam detecting means.

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