Distillation processing device

Abstract

To provide a distillation processing device, which can prevent bubbles from mixing in steam generated by heating liquid to be treated, in cooling and liquidizing the steam.SOLUTION: A distillation processing device according to the present invention is provided with: a heating tank in which liquid to be treated including low-boiling components whose boiling point is below a predetermined temperature and high-boiling components whose boiling point is over the predetermined temperature is stored; a heating mechanism that heats the liquid to be treated stored in the heating tank at the predetermined temperature; a steam outlet formed at an upper part of the heating tank; a steam passage connected to the steam outlet; a cooler that cools and liquidizes steam flowing through the steam passage; and an inflation chamber, inserted into the steam passage arranged closer to the heating tank than the cooler, which is configured to inflate air bubbles flowing from the steam outlet into the steam passage.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a distillation treatment apparatus, and more particularly to a distillation treatment apparatus used for the disposal and recycling of waste liquid generated in the manufacturing process of plated parts, electronic parts, semiconductor parts, etc. [Background technology]

[0002] Waste liquid generated in plating processes such as chrome plating, nickel plating, and zinc plating (hereinafter referred to as plating waste liquid) contains additives such as reducing agents, oxidizing agents, and brighteners in addition to plating metal ions. Therefore, plating waste liquid is disposed of after adding a coagulant or the like to it to cause the plating metal to be coagulated and precipitated and removed. In addition, when the plating waste liquid is an aqueous solution, the plating waste liquid is heated to evaporate the water, concentrated, and reduced in volume, and then disposed of as industrial waste.

[0003] For example, a vacuum distillation apparatus is used to concentrate and reduce the volume of the water-soluble waste liquid. In the vacuum distillation apparatus, the water-soluble waste liquid is heated under a pressure lower than normal pressure. This allows the water in the water-soluble waste liquid to evaporate at a temperature lower than normal pressure. Therefore, when the water-soluble waste liquid is heated, chemical reactions of the components contained in the aqueous solution waste liquid (e.g., additives contained in plating waste liquid) can be suppressed, and the water can be evaporated stably.

[0004] In a vacuum distillation apparatus, waste liquid is placed in a reduced pressure treatment tank and heated to boil the water contained in the waste liquid, and the resulting steam is taken out from a steam outlet at the top of the treatment tank. The steam taken out from the steam outlet is cooled and condensed by a condenser and discharged as distilled water.

[0005] When the water-soluble waste liquid contains a foaming component, bubbles are generated as the water in the waste liquid boils, and the bubbles may rise together with the steam and move from the steam outlet to the condenser. Since the bubbles contain the components in the waste liquid, when the bubbles are introduced into the condenser together with the steam, the components in the waste liquid are contained in the distilled water. Therefore, when the water-soluble waste liquid containing the foaming component is distilled under reduced pressure, a defoaming agent is added to the waste liquid to suppress the generation of bubbles. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2000-061203 A Summary of the Invention [Problem to be solved by the invention]

[0007] As described above, the waste liquid concentrated and reduced in volume by the vacuum distillation apparatus (concentrated waste liquid) is usually disposed of as industrial waste. Meanwhile, in recent years, there has been a demand for reusing concentrated waste liquid. However, since the defoaming agent is a component that is not originally contained in the water-soluble waste liquid, in order to reuse the concentrated waste liquid when a defoaming agent is used, it is necessary to remove the defoaming agent from the concentrated waste liquid. In response to this, instead of using a defoaming agent, a method has been adopted in which a metal net (wire mesh demister) is installed in front of the steam outlet to separate the bubbles generated in the treatment tank from the steam, and only the steam is discharged from the steam outlet.

[0008] However, when a large amount of bubbles is generated in the treatment tank, or when the bubbles grow and become large enough to fill the treatment tank, there is a problem in that the bubbles pass through the wire mesh demister and overflow from the steam outlet.

[0009] Here, we have described the case where water-soluble waste liquid is distilled under reduced pressure as the liquid to be treated. However, similar problems arise when water-insoluble waste liquid is distilled under reduced pressure, and when both water-soluble and water-insoluble waste liquids are distilled at normal pressure.

[0010] The problem to be solved by the present invention is to prevent air bubbles from being mixed into the vapor generated by heating a liquid to be treated in a distillation treatment apparatus when the vapor is cooled and liquefied. [Means for solving the problem]

[0011] The distillation treatment apparatus according to the present invention, which has been made to solve the above problems, comprises: a heat treatment tank for accommodating a liquid to be treated that contains a low-boiling point component having a boiling point equal to or lower than a predetermined temperature and a high-boiling point component having a boiling point higher than the predetermined temperature; a heating mechanism for heating the liquid to be treated contained in the heat treatment tank to the predetermined temperature; A steam outlet formed in an upper portion of the heat treatment tank; a steam flow path connected to the steam outlet; a cooler for cooling and liquefying the steam flowing through the steam flow passage; an expansion chamber that is inserted in the steam flow path on the heat treatment tank side relative to the cooler and is configured to expand bubbles that have flowed into the steam flow path from the steam outlet; The present invention is characterized by comprising:

[0012] In the distillation treatment apparatus according to the present invention, the liquid to be treated is typically a waste liquid of a treatment liquid or a cleaning liquid used in the manufacturing process, assembly process, or cleaning process of metal parts, plated parts, electronic parts, semiconductor parts, etc., but other solutions can also be used as the liquid to be treated. Any solution containing a low boiling point component and a high boiling point component can be the liquid to be treated, regardless of whether it is a water-soluble solution or a water-insoluble solution. When the liquid to be treated is a waste liquid of a treatment liquid or a cleaning liquid, the low boiling point component is typically water, and the high boiling point component is a treatment component or a cleaning component inherently contained in the treatment liquid or the cleaning liquid.

[0013] In the distillation treatment apparatus according to the present invention, when the liquid to be treated is contained in the heat treatment tank and heated to the predetermined temperature by the heating mechanism, only the low boiling point components boil and generate steam. This steam rises in the heat treatment tank and flows into the steam flow path from the steam outlet. In order to efficiently allow the steam generated in the heat treatment tank to flow into the steam flow path from the steam outlet, it is preferable that the steam outlet is formed at a position as high as possible in the heat treatment tank, but it is sufficient that it is formed above the planned liquid level of the liquid to be treated contained in the heat treatment tank. The steam that flows into the steam flow path passes through the expansion chamber and heads toward the cooler, where it is cooled and liquefied. Here, if the liquid to be treated is foamable, bubbles are generated as the low boiling point components boil, and these bubbles may flow into the steam flow path from the steam outlet together with the steam. The bubbles that flow into the steam flow path expand and become large in the expansion chamber, and become liquid by bursting or by multiple bubbles coming into contact and collapsing, and remain in the expansion chamber. Therefore, even if bubbles flow into the steam flow path from the heat treatment tank, the bubbles are prevented from heading toward the cooler.

[0014] The expansion chamber is configured to expand the bubbles flowing from the steam outlet into the steam flow passage, meaning that the internal pressure of the expansion chamber is configured to be lower than the internal pressure of the steam flow passage from the steam outlet to the expansion chamber, and examples of this include the expansion chamber being configured to have a flow passage cross-sectional area larger than the flow passage cross-sectional area of ​​the steam flow passage, or being provided with a pressure reducing means for reducing the pressure inside the expansion chamber below that of the steam flow passage. In this case, the expansion chamber is configured so that at least a part of the steam that flows into the expansion chamber from the steam outlet through the steam flow passage is not liquefied but passes through the steam flow passage toward the cooler. With this configuration, low boiling point components contained in the liquid to be treated can be separated and recovered from high boiling point components. Effect of the Invention

[0015] According to the distillation treatment apparatus of the present invention, when the vapor generated by heating the liquid to be treated in the heat treatment tank is cooled and liquefied, it is possible to prevent air bubbles from being mixed into the vapor. [Brief description of the drawings]

[0016] [Figure 1] FIG. 1 is a schematic diagram showing an embodiment in which a distillation treatment apparatus according to the present invention is applied to a waste liquid regeneration apparatus. [Diagram 2] FIG. 13 is a schematic diagram showing a modified example of the waste liquid regenerating device. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] An embodiment in which the distillation treatment apparatus according to the present invention is applied to a waste liquid regeneration apparatus will be described below with reference to Fig. 1. Fig. 1 is a schematic overall configuration diagram of the waste liquid regeneration apparatus. The waste liquid regeneration apparatus 1 is an apparatus for removing unnecessary substances from waste liquids such as treatment liquids and cleaning liquids used in the manufacturing process of plated parts, electronic parts, semiconductor parts, etc., and regenerating (recycling) them as treatment liquids, etc., and is equipped with a heat treatment tank 2 in which waste liquid as a liquid to be treated is stored, a heat exchanger 3, and a circulating water tank 4. The heat exchanger 3 and the circulating water tank 4 correspond to the cooler and recovery tank of the present invention, respectively.

[0018] The heat treatment tank 2 is a pressure-resistant, substantially cylindrical container, and an immersion-type heat exchanger 21 consisting of a coiled piping is disposed at the bottom inside the tank. The immersion-type heat exchanger 21 has an inlet 211 and an outlet 212 that open to the side of the heat treatment tank 2, and a refrigerant supply pipe 213 and a refrigerant return pipe 214 are connected to the inlet 211 and the outlet 212, respectively. The refrigerant return pipe 214 is connected to the input side of the compressor 5 via a dryer 217, a capillary tube 218, and a heat exchanger 7. The refrigerant supply pipe 213 is connected to the output side of the compressor 5, and this refrigerant supply pipe 213 is connected to the inlet 211 of the heat exchanger 21 via an air-cooled condenser 215.

[0019] A refrigerant gas as a heating medium pressurized by the operation of the compressor 5 is supplied to the immersion-type heat exchanger 21 through the refrigerant supply pipe 213 via the air-cooled condenser 215. The refrigerant gas pressurized and supplied to the immersion-type heat exchanger 21 exchanges heat with the liquid to be treated in the heat treatment tank 2 while passing through the immersion-type heat exchanger 21, thereby heating the liquid to be treated. The refrigerant gas, whose temperature has been reduced by the removal of heat, flows through the refrigerant return pipe 214, passes through the dryer 217 and the capillary tube 218, and becomes a low-pressure, low-temperature refrigerant gas. In this embodiment, the heating mechanism of the present invention is composed of the immersion-type heat exchanger 21, the compressor 5, the refrigerant supply pipe 213, the refrigerant return pipe 214, the air-cooled condenser 215, and the refrigerant gas circulating therethrough.

[0020] If the pressure and temperature of the refrigerant gas supplied to the immersion-type heat exchanger 21 are excessively high, crystals may form in the waste liquid in the heat treatment tank 2 and adhere to the immersion-type heat exchanger 21, or high-boiling-point components in the waste liquid may be distilled. To avoid such problems, a fan controller 216 is installed in the refrigerant supply pipe 213 between the air-cooled condenser 215 and the inlet 211, and the heat exhaust fan 2151 of the air-cooled condenser 215 is operated according to the pressure of the refrigerant gas in the refrigerant supply pipe 213. When the heat exhaust fan 2151 operates, the refrigerant gas in the air-cooled condenser 215 is cooled, and the pressure and temperature of the refrigerant gas flowing from the air-cooled condenser 215 through the refrigerant supply pipe 213 to the immersion-type heat exchanger 21 are reduced and adjusted to an appropriate pressure and temperature.

[0021] A wire mesh demister 22 is disposed in the space above the immersion-type heat exchanger 21 in the heat treatment tank 2. In this embodiment, three upper and lower layers of wire mesh demisters 22 are disposed substantially horizontally in the heat treatment tank 2, but the wire mesh demisters 22 may be one or two layers, or may be four or more layers. When multiple layers of wire mesh demisters 22 are disposed, the mesh sizes of the multiple wire mesh demisters 22 may all be the same or different.

[0022] A steam outlet 23 is formed at the top of the side of the heat treatment tank 2, and a raw water inlet 24 is formed at the side near the center in the vertical direction. A concentrated liquid outlet 25 is formed at the bottom of the heat treatment tank 2. A level gauge 26 for measuring the liquid level inside the heat treatment tank 2 is installed at the side of the heat treatment tank 2. The level gauge 26 has a level protection pipe 261 that is attached to the side of the heat treatment tank 2 and communicates with the inside of the heat treatment tank 2, and a level sensor 262 arranged in the level protection pipe 261. An atmosphere communication pipe 27 is connected to the top of the level gauge 26 on the side of the heat treatment tank 2, and a temperature sensor 28 for detecting the temperature inside the heat treatment tank 2 is attached to the bottom of the heat treatment tank 2. A vacuum release valve 271 is attached to the end of the atmosphere communication pipe 27. By opening the vacuum release valve 271, the inside of the heat treatment tank 2 is communicated with the atmosphere and becomes atmospheric pressure.

[0023] A raw water supply pipe 242 having a raw water supply valve 241 inserted therein is connected to the raw water inlet 24. The raw water supply pipe 242 supplies raw water (waste liquid which is the liquid to be treated) stored in a raw water tank to the heat treatment tank 2. A concentrated liquid discharge pipe 253 having a concentrated liquid discharge valve 251 and a concentrated liquid discharge pump 252 inserted therein is connected to the concentrated liquid discharge port 25. The concentrated liquid discharge pipe 253 is connected to a concentrated liquid tank.

[0024] The separator 6, which is an expansion chamber, is connected to the steam outlet 23 via the first steam outlet pipe 231. The separator 6 is made of a pressure-resistant cylindrical container and is arranged so that the cylindrical axis is in the vertical direction. A wire mesh demister 61 is arranged horizontally in the upper part of the separator 6. The separator 6 is configured so that its flow path cross-sectional area (the cross-sectional area along a plane perpendicular to the paper surface in FIG. 1) is sufficiently larger than the flow path cross-sectional area of ​​the first steam outlet pipe 231, and the volume of the separator 6 is sufficiently larger than the volume of the first steam outlet pipe 231.

[0025] In this embodiment, the flow path cross-sectional area (inner cross-sectional area (cm 2 )) is S, the volume of the separator 6 (cm 3) is defined as V, it is preferable to configure the first steam outlet pipe 231 and the separator 6 so that the area S and the volume V satisfy the following formula (1). S = 1135 × V ~ 1650 × V (1)

[0026] The separator 6 has a function of expanding the gas that has flowed into the separator 6 through the first steam outlet pipe 231. In this embodiment, steam and bubbles flow into the separator 6 from the first steam outlet pipe 231, as will be described in more detail later. The above formula (1) was found by the present inventor as a condition under which the steam that has flowed into the separator 6 does not liquefy due to a temperature drop caused by adiabatic expansion, and the gas bubbles burst and liquefy due to the adiabatic expansion of the gas inside. For example, when the liquid to be treated is plating waste liquid, the inner diameter (diameter) of the first steam outlet pipe 231 is set to 32 mm (the area of ​​the inner cross section is 8.04 cm2). 2 ), the volume of separator 6 is 11772.76 cm 3 (Top and bottom diameter 20.7 cm, height 35 cm).

[0027] The separator 6 is connected to a lower portion thereof with an introduction passage 62 for returning the residue in the separator 6 to the heat treatment tank 2. The separator 6 is also connected to an upper portion thereof with a second steam outlet pipe 232. The second steam outlet pipe 232 passes through the inside of the heat exchanger 3, and is then connected to an ejector (pressure reducer) 9 attached to the circulating water tank 4 via a check valve (check valve) 8. A vacuum pressure sensor 91 is installed in the second steam outlet pipe 232 between the heat exchanger 3 and the check valve 8. The circulating water tank 4 is equipped with float-type level switches 41 and 42 for detecting the lower and upper limit positions of the liquid level, and a temperature sensor 43. The circulating water tank 4 is also provided with a distilled water outlet 44 at the upper portion of the side thereof and a reflux port 45 at the lower portion thereof. The distilled water outlet 44 is connected to a water intake pipe 443 in which a flow rate sensor 441 and a discharge valve 442 are inserted. When the compressor 5 is driven, the discharge valve 442 is opened, and the distilled water in the circulating water tank 4 (more precisely, the distilled water in the circulating water tank 4 that has exceeded the distilled water outlet 44) is discharged from the distilled water outlet 44 through the water intake pipe 443. When the compressor 5 stops, the discharge valve 442 is closed, and the distilled water is no longer discharged from the circulating water tank 4.

[0028] One end of a water pipe 452 with a vacuum circulation pump 451 inserted therein is connected to the reflux port 45. The heat exchanger 7 and the heat exchanger 3 are inserted in the water pipe 452, and the other end of the water pipe 452 is connected to the ejector 9. By the action of the vacuum circulation pump 451, the distilled water stored in the circulating water tank 4 is pressure-fed through the water pipe 452 from the reflux port 45 to the heat exchanger 7 and the heat exchanger 3 and then to the ejector 9. By pressure-fed distilled water to the ejector 9, the pressure inside the ejector 9 is reduced, and the second steam outlet pipe 232 is sucked, so that the insides of the second steam outlet pipe 232, the heat treatment tank 2, and the separator 6 are almost in a vacuum state. In the following description, the heat exchanger 3 is called the first heat exchanger 3, and the heat exchanger 7 is called the second heat exchanger 7.

[0029] In addition, when the liquid level in the circulating water tank 4 falls below the lower limit, the vacuum circulation pump 451 may run idle. Therefore, in this embodiment, when the float-type level switch 41 detects that the liquid level in the circulating water tank 4 has fallen below the lower limit, the entire device is stopped and an alarm is issued. When the liquid level in the circulating water tank 4 exceeds the upper limit, some malfunction may have occurred in the discharge valve 442, the water intake pipe 443, etc. Therefore, in this embodiment, when the float-type level switch 42 detects that the liquid level in the circulating water tank 4 has exceeded the upper limit, the entire device is stopped and an alarm is issued. As a means for outputting an alarm, a buzzer, a lamp, etc. may be used.

[0030] The second heat exchanger 7 is configured to pass low-temperature refrigerant gas through the refrigerant return pipe 214, and the distilled water flowing through the water guide pipe 452 exchanges heat with the refrigerant gas flowing through the refrigerant return pipe 214 when passing through the second heat exchanger 7. As a result, the distilled water is cooled and the refrigerant gas is heated.

[0031] Next, the operation of the waste liquid regeneration device 1 will be described by taking as an example the case where plating waste liquid generated in the manufacturing process or cleaning process of plated parts is treated using the waste liquid regeneration device 1. Note that the plating waste liquid contains plating processing liquid and water, with the water corresponding to the low boiling point component and the plating processing liquid corresponding to the high boiling point component.

[0032] First, the vacuum release valve 271 is closed and the vacuum circulation pump 451 is driven. Then, by the action of the vacuum circulation pump 451, the air in the circulating water tank 4 in the initial state (a state in which nothing is contained) passes through the water guide pipe 452, passes through the second heat exchanger 7 and the first heat exchanger 3, and is pumped to the ejector 9. As a result, the insides of the heat treatment tank 2, the first steam outlet pipe 231, the separator 6, and the second steam outlet pipe 232 are sucked and reduced in pressure.

[0033] Then, when the detection value of the vacuum pressure sensor 91 reaches a predetermined vacuum value (vacuum degree), the raw water supply valve 241 is opened, and the plating waste liquid is fed into the heat treatment tank 2 from the raw water inlet 24 through the raw water supply pipe 242. The amount (liquid level) of the plating waste liquid in the heat treatment tank 2 is detected by the level sensor 262, and the plating waste liquid continues to be fed into the heat treatment tank 2 until the liquid level of the plating waste liquid reaches a predetermined set value.

[0034] When the liquid level in the heat treatment tank 2 reaches a predetermined set value and the internal pressure of the heat treatment tank 2 reaches a predetermined vacuum value, the compressor 5 is driven. As a result, the refrigerant gas is pushed out from the compressor 5 and circulates through the air-cooled condenser 215, the refrigerant supply pipe 213, the immersion type heat exchanger 21, the refrigerant return pipe 214, the dryer 217, and the capillary tube 218 in this order, and returns to the compressor 5. The circulating refrigerant gas flows through the refrigerant supply pipe 213 in a state heated by the compressor 5 and flows into the immersion type heat exchanger 21. In addition, the air in the circulating water tank 4 is pressure-fed to the ejector 9 through the water guide pipe 452, generating a suction force, and the pressure in the heat treatment tank 2 drops below atmospheric pressure.

[0035] In this state, a predetermined amount of plating waste liquid is charged into the heat treatment tank 2 through the raw water charging port 24. The amount of plating waste liquid charged is set according to the volume of the heat treatment tank 2 and the height of the submerged heat exchanger 21, and the liquid level of the predetermined amount of plating waste liquid charged into the heat treatment tank 2 is located above the upper part of the submerged heat exchanger 21. In addition, the amount of distilled water discharged from the circulating water tank 4 is measured by the flow rate sensor 41. Then, while the plating waste liquid is being treated, an operation of, for example, 1 L of distilled water being discharged from the circulating water tank 4 and at the same time 1 L of plating waste liquid being charged into the heat treatment tank 2 through the raw water charging port 24 is continuously performed so that the liquid level of the plating waste liquid is always located above the upper part of the submerged heat exchanger 21.

[0036] The plating waste liquid introduced into the heat treatment tank 2 is heated by heat exchange with the refrigerant gas flowing through the immersion type heat exchanger 21 in a heated state. At this time, the fan controller 216 controls the driving of the fan 2151 of the air-cooled condenser 215 so that the temperature of the plating waste liquid in the heat treatment tank 2 becomes the boiling point of water under the pressure state in the heat treatment tank 2. As a result, the water contained in the plating waste liquid boils and evaporates to generate steam. The steam generated in the heat treatment tank 2 flows into the separator 6 from the steam outlet 23 through the first steam outlet pipe 231. The steam that has flowed into the separator 6 passes through the second steam outlet pipe 232, the heat exchanger 3, the check valve 8, and the ejector 9, and flows into the circulating water tank 4.

[0037] At least a part of the steam flowing through the second steam outlet pipe 232 is cooled by heat exchange with the refrigerant (water generated by liquefying the steam, as described later) flowing through the first heat exchanger 3 when passing through the first heat exchanger 3, and is liquefied into water (distilled water) and flows into the circulating water tank 4. The distilled water that flows into the circulating water tank 4 passes through the water guide pipe 452 from the return port 45 at the bottom of the circulating water tank 4 by the action of the vacuum circulation pump 451, passes through the second heat exchanger 7 and the first heat exchanger 3 in order, and is returned to the circulating water tank 4 through the ejector 9. When the distilled water flowing through the water guide pipe 452 passes through the second heat exchanger 7, the distilled water is cooled by heat exchange with the refrigerant gas that has been reduced in pressure and temperature in the capillary tube 218, and then, when passing through the first heat exchanger 3, the distilled water exchanges heat with the steam flowing through the second steam outlet pipe 232, thereby cooling and liquefying the steam.

[0038] On the other hand, when bubbles are generated by the components contained in the plating liquid as the water in the plating waste liquid evaporates in the heating treatment tank 2, the bubbles rise in the heating treatment tank 2 together with the steam. At this time, some of the bubbles are crushed by the wire mesh demister 22, become liquid, and are returned to the plating waste liquid. Also, the bubbles that reach the steam outlet 23 without being crushed by the wire mesh demister 22 flow from the steam outlet 23 into the first steam outlet pipe 231 together with the steam, and flow through the outlet pipe 231 into the separator 6. The bubbles that flow into the separator 6 expand and burst in the separator 6, become liquid, and remain in the separator 6. Also, even if some of the bubbles that flow into the separator 6 rise together with the steam in the same state (i.e., without bursting), they are crushed by the wire mesh demister 61 installed in the upper space in the separator 6, become liquid, and fall into the separator 6 to be stored. The residue in the separator 6 is returned to the heating treatment tank 2 through the introduction path 62. Since the bubbles are mainly formed from the plating processing liquid in the plating waste liquid, when the residue is returned to the heat treatment tank 2, the proportion of plating processing liquid in the plating waste liquid in the heat treatment tank 2 increases, and the plating waste liquid becomes concentrated.

[0039] By repeating the above operations, the water contained in the plating waste liquid stored in the heat treatment tank 2 is distilled and separated and collected in the circulating water tank 4, while the proportion of plating treatment liquid contained in the plating waste liquid in the heat treatment tank 2 increases and the plating waste liquid becomes concentrated. The concentrated plating waste liquid (concentrated liquid) is sucked from the heat treatment tank 2 by opening the discharge valve 251 and driving the discharge pump 252, and is collected in a storage tank through the concentrated liquid discharge port 25 and the concentrated liquid discharge pipe 253.

[0040] Thus, according to this embodiment, the plating waste liquid contained in the heat treatment tank 2 can be separated into water vapor, which is a low boiling point component, and the plating treatment liquid, which is a high boiling point component, and these can be recovered as reclaimed water and plating treatment liquid, respectively. The recovered plating treatment liquid does not contain components such as an antifoaming agent that are not originally contained in the plating treatment liquid, so the recovered plating treatment liquid can be reused. Furthermore, even if a large number of bubbles are generated by heating the plating waste liquid due to the absence of an antifoaming agent, the bubbles can be crushed by the wire mesh demister 22 arranged in the heat treatment tank 2 to separate the water vapor from the bubbles, and the bubbles can be further burst in the separator 6 to separate the water vapor from the bubbles. Moreover, in this embodiment, the wire mesh demister 61 is arranged in the upper space in the separator 6, and the bubbles that have not burst in the separator 6 are crushed and separated from the water vapor. Therefore, the water vapor generated by heating the plating waste liquid can be passed through the first heat exchanger 3 with the bubbles removed therefrom. The water vapor is cooled as it passes through the first heat exchanger 3 and turns into water, which is then recovered in the circulating water tank 4. However, the amount of plating treatment liquid contained in the water recovered in the circulating water tank 4 can be reduced, and this water can be used as reclaimed water.

[0041] [Variations] The present invention is not limited to the above-mentioned embodiment, and various modifications are possible. For example, in the first embodiment, the wire mesh demister 61 is disposed inside the separator 6, but as shown in FIG. 2, the wire mesh demister in the separator 6 can be omitted. In this case, the separator 6 is composed of only a simple cylindrical container, but if the amount of bubbles flowing into the separator 6 is small or the bubbles are prone to bursting, the bubbles can be liquefied even without the wire mesh demister in the separator 6. Whether or not to dispose the wire mesh demister in the separator 6 can be determined depending on the viscosity of the liquid to be treated supplied to the heat treatment tank 2, the degree of vacuum in the separator 6, and the like.

[0042] In addition, since the separator 6 utilizes the fact that bubbles expand and burst, for example, the inner wall of the separator 6 may be configured so that the expanded bubbles burst easily. Examples of a configuration that makes the expanded bubbles burst easily include attaching a needle-shaped member to the inner wall of the separator 6 with its pointed end facing inward, or roughening the inner wall surface of the separator 6 with a large number of protrusions, thorns, etc. Preferable examples of the location where the needle-shaped member is attached and the location where the inner wall surface is roughened include locations where the expanded bubbles tend to adhere, such as the upper surface of the separator 6 and the surface around the connection between the separator 6 and the second steam outlet pipe 232, but other locations may also be used. With such a configuration, the expanded bubbles can be burst before they burst, so that the time it takes for the bubbles to burst after they flow into the separator 6 can be shortened.

[0043] In the above embodiment, the distillation treatment device according to the present invention is used as a waste liquid regeneration device, but it can also be used as a waste liquid treatment device. In this case, the concentrated solution of plating waste liquid remaining in the heat treatment tank 2 is discarded. Even in the case of discarding, there is an advantage that it is easier to discard if the concentrated solution does not contain a defoaming agent.

[0044] [Aspects] It will be apparent to those skilled in the art that the above-described exemplary embodiments are illustrative of the following aspects.

[0045] (Item 1) A distillation treatment apparatus according to one aspect of the present invention comprises: a heat treatment tank for accommodating a liquid to be treated that contains a low-boiling point component having a boiling point equal to or lower than a predetermined temperature and a high-boiling point component having a boiling point higher than the predetermined temperature; a heating mechanism for heating the liquid to be treated contained in the heat treatment tank to the predetermined temperature; A steam outlet formed in an upper portion of the heat treatment tank; a steam flow path connected to the steam outlet; a cooler for cooling and liquefying the steam flowing through the steam flow passage; an expansion chamber that is inserted in the steam flow path on the heat treatment tank side relative to the cooler and is configured to expand bubbles that have flowed into the steam flow path from the steam outlet; It is equipped with the following.

[0046] According to the distillation treatment apparatus of paragraph 1, an expansion chamber is provided in the vapor flow path connecting the heat treatment tank and the cooler, so that even if bubbles consisting mainly of high boiling point components are generated by heating the liquid to be treated in the heat treatment tank and flow into the vapor flow path from the vapor outlet, the bubbles expand and break when they flow into the expansion chamber. Therefore, it is possible to prevent bubbles from being mixed into the vapor of low boiling point components when the vapor is cooled and liquefied.

[0047] (Item 2) The distillation treatment apparatus according to item 2 is the distillation treatment apparatus according to item 1, in which a demister made of a metal net is provided in the heat treatment tank.

[0048] According to the distillation treatment apparatus of the second aspect, it is possible to prevent bubbles generated in the heat treatment tank from rising within the heat treatment tank and reaching the vapor outlet.

[0049] (Item 3) The distillation treatment apparatus according to item 3 is the distillation treatment apparatus according to item 1 or 2, in which a demister made of a metal mesh is provided in the expansion chamber.

[0050] According to the distillation treatment apparatus of the third aspect, it is possible to prevent air bubbles that have flowed into the expansion chamber and not been destroyed in the expansion chamber from leaving the expansion chamber and heading toward the cooler.

[0051] (Item 4) The distillation treatment apparatus according to item 4 is the distillation treatment apparatus according to any one of items 1 to 3, further comprising a recovery tank for recovering a liquefied product produced when the vapor is cooled and liquefied in the cooler.

[0052] According to the distillation treatment apparatus of the fourth aspect, the liquefied product obtained by liquefying the vapor separated from the liquid to be treated can be easily recovered and reused.

[0053] (Item 5) The distillation treatment apparatus according to item 5 is the distillation treatment apparatus according to items 1 to 4, further comprising a pressure reducing mechanism that reduces the pressure inside a flow path from the heat treatment tank through the expansion chamber and the cooler to the recovery tank.

[0054] According to the distillation treatment apparatus of the fifth aspect, the low boiling point components contained in the liquid to be treated stored in the heat treatment tank can be boiled at a temperature lower than normal pressure. Also, bubbles generated by the boiling of the liquid to be treated can be efficiently expanded in the expansion chamber.

[0055] (Item 6) The distillation treatment apparatus according to item 6 is the distillation treatment apparatus according to any one of items 1 to 5, further comprising a reflux path for returning the residue accumulated in the expansion chamber to the heat treatment tank.

[0056] According to the distillation treatment apparatus of the sixth aspect, the bubbles expand and break in the expansion chamber, and the high boiling point components become liquid, and can be returned to the heat treatment tank and treated again. [Explanation of symbols]

[0057] 1...Waste liquid recycling device 2. Heat treatment tank 21…Immersion heat exchanger 213…Refrigerant supply pipe 214...Refrigerant return pipe 215…Air-cooled condenser 22…Wire mesh demister 23...Steam outlet 231…First steam outlet pipe 232…Second steam outlet pipe 24…Raw water input port 25…Concentrated liquid outlet 26…Liquid level gauge 27…Atmospheric communication pipe 28...Temperature sensor 3...Heat exchanger (first heat exchanger) 4…Circulating water tank 451…Vacuum Circulation Pump 452…Water pipe 5. Compressor 6…Separator 61…Wire mesh demister 62...Introduction path 7...Heat exchanger (second heat exchanger) 9…Ejector 91...Vacuum pressure sensor

Claims

1. a heat treatment tank for accommodating a liquid to be treated that contains a low-boiling point component having a boiling point equal to or lower than a predetermined temperature and a high-boiling point component having a boiling point higher than the predetermined temperature; a heating mechanism for heating the liquid to be treated contained in the heat treatment tank to the predetermined temperature; A steam outlet formed in an upper portion of the heat treatment tank; a steam flow path connected to the steam outlet; a cooler for cooling and liquefying the steam flowing through the steam flow passage; an expansion chamber that is inserted in the steam flow path on the heat treatment tank side relative to the cooler and is configured to expand bubbles that have flowed into the steam flow path from the steam outlet; A distillation treatment device comprising:

2. 2. The distillation treatment apparatus according to claim 1, wherein a demister made of a metal net is provided in the heat treatment tank.

3. 2. The distillation processing apparatus according to claim 1, wherein a demister made of a metal mesh is provided in the expansion chamber.

4. The distillation treatment apparatus according to claim 1 , further comprising a recovery tank for recovering a liquefied product produced when the vapor is cooled and liquefied in the cooler.

5. The distillation processing apparatus according to claim 4 , further comprising a decompression mechanism for decompressing an interior of a flow path extending from the heat treatment tank through the expansion chamber and the cooler to the recovery tank.

6. The distillation treatment apparatus according to any one of claims 1 to 5, further comprising a return passage for returning the material accumulated in the expansion chamber to the heat treatment tank.

7. The distillation treatment apparatus according to any one of claims 1 to 5, further comprising a residue recovery tank for recovering residue in the heat treatment tank.

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