JP4155871B2 - Vacuum evaporation concentrator - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a vacuum evaporation concentrator.
[0002]
[Prior art]
In the chemical industry that uses various aqueous solutions such as plating, the vacuum evaporation concentrator can recover and use the aqueous solution, so that the components can be used effectively, and the discharge of the wastewater itself can be made unnecessary. At that time, it is widely used because of the effect that the waste water treatment and the equipment therefor become unnecessary.
[0003]
Here, many types of vacuum evaporation concentrators are described in, for example, “Vacuum Evaporator (1)” (Non-Patent Document 1) by Shinzo Sumitani. Therefore, there was no compact thing that could be easily installed between certain facilities.
[0004]
[Non-Patent Document 1]
Shinzo Sumiya “Vacuum Evaporator (1)” Chemical Factory, Vol. 6, No. 8, pp. 81-84, August 1962, published by Nikkan Kogyo Shimbun, Inc.
[Problems to be solved by the invention]
In a conventional vacuum evaporative concentration apparatus, an evaporative boiling can part that generates the vapor of the liquid to be treated and a cooling condensation chamber part that cools and condenses the vapor supplied from the evaporative boiling can part are provided separately. Therefore, a large area is required for installation of the apparatus, the height is high, and a connection pipe is required, making it difficult to make the system compact.
[0006]
Here, for the purpose of downsizing, the inventors of the present invention prototyped a vacuum evaporation concentrating apparatus in which piping for connecting them was omitted and a cooling condensing chamber part was provided at a position adjacent to the upper part of the evaporation boiling can part.
[0007]
However, at that time, foam or mist generated in the liquid to be treated inside the evaporative boiling can is brought into the cooling condensation chamber together with the vapor, and should not be originally included in the liquid condensed and recovered in the cooling condensation chamber. There arises a problem that a large amount of non-volatile components are contained in the liquid to be treated.
[0008]
An object of the present invention is to provide a reduced-pressure evaporative concentration apparatus that improves the above-described conventional problems, that is, is compact but does not contain non-volatile components in the liquid to be treated on the evaporative condensed water side. And
[0009]
[Means for Solving the Problems]
In order to solve the above-described problems, the reduced-pressure evaporative concentration apparatus of the present invention provides steam supplied from the evaporative boiling can portion adjacent to the upper portion of the evaporative boiling can portion that generates the vapor of the liquid to be treated. A cooling condensing chamber that cools and condenses the liquid, and a vapor passage provided above the evaporation surface that guides the vapor of the liquid to be processed evaporated from the evaporation surface of the liquid to be processed to the upper part of the cooling condensation chamber, and cooling condensation In a vacuum evaporation concentrating apparatus having a cooling serpentine tube for condensing the vapor of the liquid to be treated in the chamber and around the vapor passage, the liquid or solid in the vapor boiling can reaches the cooling condensation chamber This is a vacuum evaporation / concentration device having a mist removal means in the vapor passage for preventing the evaporation, and with such a configuration, the vacuum evaporation / concentration device is compact and does not contain non-volatile components in the liquid to be treated on the evaporation condensed water side. Is possible.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
In the present invention, when the mist removing means is composed of a bubble cap tray and a laminate of hydrophobic fiber webs, it is possible to more effectively prevent non-volatile components from being mixed in the liquid to be treated on the evaporation condensed water side. can do.
[0011]
In order to obtain a high effect, it is preferable that the bubble cap tray is disposed on the vapor boiling can side of the vapor passage and the web of hydrophobic fibers is disposed on the cooling condensation chamber side.
[0012]
As the resin constituting the hydrophobic fiber, a resin having low wettability to water is selected. Examples of such resins include fluorine resins such as polytetrafluoroethylene, polyvinylidene resins, and polyolefin resins such as polyethylene and polypropylene, but are inexpensive and polyolefin resins that have a low environmental impact during final disposal. It is desirable that
[0013]
It is desirable to select a web laminate composed of such fibers so that the distance between the fibers constituting the fibers is about 10 to 200 μm. Moreover, it is desirable to arrange | position so that the lamination direction may become perpendicular | vertical and at right angles with the flow direction of a vapor | steam. With such a configuration, mist in water vapor can be more effectively removed.
Such a laminate of webs is held by a metal or resin net having a relatively coarse opening having an opening of 2 to 3 mm, for example.
[0014]
Here, the reduced pressure evaporation concentration apparatus of the present invention will be described with reference to the drawings.
FIG. 1 shows a model cross-sectional view of an example of a vacuum evaporation and concentration apparatus of the present invention.
The vacuum evaporating and concentrating apparatus 1 is a cylindrical cooling unit that cools and condenses the vapor supplied from the evaporative boiling can 2 adjacent to and above the cylindrical evaporative can 2 that generates the vapor of the liquid 3 to be treated. A cylindrical vapor passage 5 provided above the evaporation surface 3a, which has a condensation chamber portion 4 and guides the vapor of the treatment liquid evaporated from the evaporation surface 3a of the treatment liquid 3 to the upper portion of the cooling condensation chamber portion 4. A vacuum evaporating and concentrating device comprising a cooling serpentine tube 4a for condensing the vapor of the liquid to be treated in the cooling condensing chamber 4 and around the vapor passage, and the liquid in the vapor boiling can 2 Alternatively, it is a vacuum evaporation concentrating device in which a bubble cap tray 5a and a laminate 5b of hydrophobic fiber webs are arranged in the vapor passage 5 as mist removing means for preventing the solid from reaching the cooling condensation chamber.
[0015]
A cooling condensing tube 4a is concentrically arranged around the cooling condensing chamber portion 4, the steam passage (cylindrical shape expanding on the upper side of the bubble cap tray 5a in the middle), and the steam passage 5. . In this example, since the uppermost part of the cooling serpentine tube 4a is disposed at a position lower than the outlet of the steam passage 5, the entire cooling serpentine tube 4a is effectively used. In this example, a single row of cooling serpentine tubes is provided, but a plurality of rows of cooling serpentine tubes may be used. Furthermore, in order to improve the contact efficiency between the airflow and the cooling serpentine tube 4a, a baffle plate may be provided so that the airflow around the cooling serpentine tube flows in a zigzag shape.
[0016]
In this vacuum evaporation concentrating apparatus 1, the steam boiling can part 2 is provided with a heater 2a for heating the liquid 3 to be treated, and a heating medium (water vapor in this example) is supplied from the inlet 2a1 to the outlet 2a2. By feeding, the liquid 3 to be processed is heated to a predetermined temperature. At this time, the liquid 3 to be treated in the steam boiling can part 2 is circulated from the bottom of the steam boiling can part 2 through the piping and the introduction pipe 2b by the action of the pump P1.
[0017]
In addition, in this vacuum evaporation concentrator 1, the liquid 3 to be treated is heated inside the steam boiling can 2 and it is not necessary to provide a heat exchanger or the like. .
[0018]
Thus, the volatile component of the liquid 3 to be treated heated by the heat medium evaporates from the evaporation surface 3a, is led to the vapor passage 5, and the bubble cap tray 5a provided in the vapor passage 5 and the hydrophobic fibers (this In the example, the laminate 5b of polypropylene) reaches the upper portion of the cooling condensing chamber 4 in a state where liquid or solid components such as splashes are sufficiently removed. Here, polypropylene nets (apertures of about 3 mm) 5c1 and 5c2 are arranged above and below the hydrophobic fiber web laminate 5b to hold the hydrophobic fiber web laminate 5b. Has been.
[0019]
The inside of the cooling condensing chamber 4 is directed from the inlet 4a1 to the outlet 4a2 of the helical cooling pipe 4a, that is, the cooling condensing chamber 4 is moved from the bottom to the top of the refrigerant (in this example, the cooling water is directed from the bottom to the top). Therefore, the vapor having reached the cooling condensing chamber portion is condensed and liquefied in the cooling condensing chamber portion 4.
[0020]
The condensed liquid is discharged to the condensate receiver 10 outside the vacuum evaporation concentrating device 1 from the discharge port 4b for discharging the liquid provided in the lower wall portion of the cooling condensing chamber section 4 to the outside of the cooling condensing chamber section. When the condensate in the condensate receiver 10 increases and the liquid level reaches a predetermined position, it is discharged outside the condensate receiver 10 by the action of the pump P2.
[0021]
It should be noted that the inside of the vacuum evaporation concentrating device needs to be kept in a reduced pressure state for efficient concentration, but the exhaust port 4c1 for exhausting inside the cooling condensing chamber 4 is different from the exhaust port 4b. Separately, it is provided at a higher position in the cooling condensation chamber portion 4 than the discharge port 4b. For this reason, the condensed liquid accumulated in the cooling condensation chamber portion 4 does not reach the exhaust port 4c1, and efficient exhaust is maintained.
[0022]
It is most desirable that the lower end of the baffle plate 4d is lower than the lower end of the cooling serpentine tube 4a as in this example.
[0023]
Furthermore, in this example, the exhaust port 4 c 1 is provided in the vicinity of the steam passage 5. Here, since the steam passage 5 has a columnar shape and is arranged concentrically with the cylindrical cooling condensing chamber 4, the exhaust port 4 c 1 is provided near the center of the cooling condensing chamber 4. Therefore, the condensed liquid accumulated in the cooling condensation chamber portion 4 is more reliably collected because the cooling condensation chamber portion 4 is arranged at a position separated from the discharge port 4b provided in the lower wall portion of the cooling condensation chamber portion 4. Reaching the exhaust port 4c1 is prevented.
[0024]
In FIG. 1, the exhaust port 4 c 1 and the pipe connected to the exhaust port 4 c 1 are cross-sectional views on the surface having the connection port 4 c 2 connected to the outside of the vacuum evaporation concentrating device 1, but it is difficult to understand. As shown in the perspective view (partial view), these pipes occupying the cross section of the steam passage 5 are extremely small, and the flow of steam from the steam boiling can 2 to the cooling condensing chamber 4 is not hindered by these pipes. . The connection port 4c2 is connected to an external exhaust pump P3.
[0025]
Further, as shown in FIG. 1, the airflow in the cooling condensing chamber 4 once reaches a position lower than the lower end of the cooling serpentine tube 4a inside the cooling condensing chamber 4 and then reaches the exhaust port 4c1. Since the baffle plate 4d as an airflow guiding means for guiding is provided, the condensable component (usually moisture) in the airflow reaching the exhaust port 4c1 is removed as much as possible, so that the exhaust efficiency is high. Since the pressure inside the vacuum evaporation concentrating device can be further reduced, the evaporation efficiency is improved.
[0026]
In this example, two exhaust ports 4c1 are provided on the side surface of the cylindrical steam passage 5 at target positions (positions rotated by 180 °) with respect to the center thereof, and are sucked into the two exhaust ports 4c1. The cooling condensing chamber section 4 has two air flows, and cooling by the cooling serpentine tube 4a becomes more efficient. As described above, it is desirable that the exhaust port is provided with a plurality of the exhaust ports, usually two to four, spaced apart from each other.
[0027]
【The invention's effect】
The vacuum evaporation / concentration apparatus of the present invention is a vacuum evaporation / concentration apparatus that is compact but does not contain non-volatile components in the liquid to be treated on the evaporation condensed water side.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of a model showing an example of a vacuum evaporation and concentration apparatus according to the present invention.
FIG. 2 is a model perspective view (partial view) in the vicinity of a steam passage.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Vacuum evaporation concentrating apparatus 2 Evaporative boiling can part 2a Heater 3 Processed liquid 3a Evaporating surface 4 Cooling condensing chamber part 4a Cooling snake tube 4a1 Inlet 4a2 Discharge port 4b Discharge port 4c1 Exhaust port 4c2 Connection port 4d Baffle plate 5 Steam passage 5a Bubble cap tray 5b Hydrophobic fiber web laminate 5c1, 5c2

Claims (4)

A cooling condensing chamber for cooling and condensing steam supplied from the evaporative boiling can adjacent to the upper part of the evaporative boiling can generating the vapor of the liquid to be treated;
A vapor passage provided above the evaporation surface that guides the vapor of the treatment liquid evaporated from the evaporation surface of the treatment liquid to the upper portion of the cooling condensation chamber;
In a reduced pressure evaporation concentrating apparatus provided with a cooling serpentine tube for condensing the vapor of the liquid to be treated in the cooling condensing chamber and around the vapor passage,
Mist removal means for preventing from reaching the liquid or solid vapor boil cans portion cooling and condensing chamber possess a steam passage,
A discharge port for discharging the liquid condensed in the cooling condensing chamber to the cooling condensing chamber portion lower wall portion or the cooling condensing chamber portion wall bottom portion to the outside of the cooling condensing chamber portion;
A pump for discharging the condensed liquid connected to the outlet;
Separately from the exhaust port, and an exhaust port for exhausting the inside of the cooling condensing chamber at a higher position in the cooling condensing chamber than the exhaust port,
An exhaust pump connected to the exhaust port; and
The cooling condensation chamber portion of the air flow once the vacuum evaporation apparatus according to claim Rukoto of having a stream guiding means for guiding to reach the exhaust port after reaching the lower cooling condensation chamber portion inside the cooling flexible tube position .   The reduced-pressure evaporative concentration apparatus according to claim 1, wherein the mist removing means comprises a bubble cap tray and a laminate of hydrophobic fiber webs. The cooling condensing chamber is cylindrical or substantially cylindrical, and a cylindrical or substantially cylindrical steam passage is arranged at the center thereof, and spiral cooling serpentine tubes are arranged concentrically around the steam passage, and The reduced-pressure evaporative concentration apparatus according to claim 1 or 2, wherein the exhaust port is provided in the vicinity of the vapor passage . The reduced-pressure evaporative concentration apparatus according to claim 3, wherein a plurality of the exhaust ports are provided apart from each other .

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