JPS6148961B2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to an evaporator for solvent recovery.

The present inventor has previously provided a safe solvent recovery device with good heat transfer efficiency, in which the inner circumferential wall of an evaporator that accommodates and evaporates and heats waste solvent has a heat pipe structure.

The present invention can prevent heat dissipation to areas other than the heat absorption part of the evaporator with a heat pipe structure, and
To provide an evaporator for solvent recovery, which can heat an endothermic part to the highest temperature, increase heat transfer efficiency, save electric power, and shorten the time required for solvent recovery.

The present invention will be explained below based on examples.

FIG. 1 shows an embodiment of the present invention, in which a solvent container 2 that can be taken in and out of an evaporator 1 is configured to evaporate and heat the solvent with an evaporator 3 having a heat pipe structure. The evaporator 1 is formed into a box shape with an evaporator 3 and a lid 4, each having a heat insulating structure on the outer periphery. The internal space 7 formed by the inner circumferential walls 5 and 6 of the evaporator 1 has a space 18 normally used for storing waste solvent.
A general-purpose solvent container 2 such as a can can be housed in and taken out from an evaporator 3 with a lid 4 which is hinged so as to be openable and closable. As shown in the figure, the inner peripheral wall 5 of the evaporator 3 is a bottomed double cylindrical heat pipe having a predetermined withstand pressure between a cylindrical heat pipe inner wall 8 and a heat pipe outer wall 9 formed of a non-magnetic stainless steel plate or the like. A predetermined amount of a working fluid 11 of a high boiling point organic substance such as water or dowsum is sealed in a small gap 10 between the inner wall 8 of the heat pipe and the outer wall 9 of the heat pipe. It is preferable to use an appropriate working fluid 11 that corresponds to the evaporation temperature of the solvent to be recovered, and to seal the space 10 under reduced pressure. An electromagnetic induction heating device 12 is disposed at the bottom of the inner circumferential wall 5 having a bottomed double cylindrical heat pipe structure, and a carbon steel plate 18 is integrally attached to the inside of the bottom surface of the heat pipe outer wall 9. A ferromagnetic material 13 such as a chromium-nickel steel plate can be uniformly inductively heated via a non-magnetic heat pipe outer wall 9. The electromagnetic induction heating device 12 includes a spiral induction coil 15 supported by a support base 14 and wound with a predetermined number of turns, arranged parallel to the bottom surface of the inner circumferential wall 5 at a predetermined interval, and connected to a high-frequency oscillator (not shown). ) and is also connected to a predetermined ground connection so that it can be operated electromagnetically. A temperature sensor 16 installed at the lower part of the inner circumferential wall 5, a timer of a control device (not shown), etc. are used to heat the waste solvent loaded into the solvent container 2 according to a predetermined value so that the solvent can evaporate. .
17 is a solvent outflow pipe for connecting to a condensing device (not shown); 18 is a connector detachably connected to the can opening 19 of the solvent container 2; 20 is a connector pressing spring; 21
2 is a pressure regulating device for the internal space 7, 22 is an assistant for the lid body, and 23 is a handle for the solvent container.

Then, the solvent container 2 loaded with a predetermined amount of waste solvent is stored in the internal space 7 of the evaporator 1, and the predetermined connections are made to the condensing device, control device, etc., the temperature and timer are set, and the power is turned on. Then, the electromagnetic induction heating device 12 is activated. The magnetic lines of force generated from the induction coil 15 of the electromagnetic induction heating device 12 are transmitted to the heat pipe outer wall 9 via the non-magnetic heat pipe outer wall 9.
A magnetic circuit is formed through the ferromagnetic material 13 inside. An eddy current flows through the ferromagnetic material 13 due to the magnetic field lines passing through the ferromagnetic material 13, heating the ferromagnetic material 13 by Joule loss, and absorbing heat at the bottom of the bottomed double cylindrical heat pipe structure of the inner peripheral wall 5. area is heated. When the heat absorbing section is heated, the working fluid 11 sealed in the space 10 is heated and evaporated, and flows into the space 1 toward the bottom and circumferential side of the heat pipe inner wall 8, which is the cooling section.
0 flows through the heat pipe, and the latent heat obtained in the heat absorption part is released to the inner wall 8 of the heat pipe and stored in the internal space 7.
, and quickly and uniformly transfers a large amount of heat from the heat absorbing section to the cooling section. The steam condenses in the cooling section, and the condensed working fluid 11 flows back to the heat absorption section due to its own weight. In this way, a large amount of heat transfer occurs repeatedly over the bottom and circumferential sides of the solvent container. Therefore, even though the electromagnetic induction heating device, which is the heating source for the waste solvent, is installed outside the inner peripheral wall, it is possible to directly heat the working fluid inside the inner peripheral wall, minimizing wasted heat radiation. It can be prevented and heat pipe heating can be performed. Moreover, since the heat absorbing portion of the heat pipe structure can be heated to the highest temperature, the heat transfer efficiency can be increased. In addition, when the outer wall of the heat pipe, which is the inner peripheral wall of the heat pipe structure, is made of stainless steel, conventionally there was a problem of low heat transfer efficiency, but in the present invention, heating can be performed directly inside the outer wall of the heat pipe, so the thermal conductivity is The outer wall of the heat pipe, which has a small diameter, acts as a heat insulator and prevents heat from being radiated to the outside, thereby further increasing heat pipe heating and improving the efficiency of heat transfer to the waste solvent. In addition, the bottomed, double-cylindrical inner peripheral wall can sufficiently separate the solvent from the heating source, and because the heating is generated by eddy current generated by magnetic lines of force, no flames are generated, further increasing safety. . Then, the solvent is heated to a constant temperature for a predetermined period of time, and the solvent is heated to the canister 19 and the connector 1.
8. The solvent is condensed in a condensing device connected as specified through the solvent outflow pipe 17, and the solvent is sequentially recovered in a recovery can (not shown).

FIG. 2 shows another embodiment of the inner peripheral wall 5 and the electromagnetic induction heating device 12 of the present invention. The heat absorption part of the bottom surface of the heat pipe outer wall 9 of the inner peripheral wall 5 is integrally formed with a ferromagnetic material such as a carbon steel plate or 18 chromium nickel steel plate, and a heat-resistant tempered glass is provided between the inner peripheral wall 5 and the electromagnetic induction heating device 12. A thin heat insulating plate 23 made of a ceramic plate, a non-magnetic stainless steel plate, or the like is provided.

In this example, the heat absorbing part on the bottom of the inner peripheral wall can be directly heated by induction, and the same effect as above can be achieved.In addition, the heat insulating plate can prevent heat dissipation to the surrounding area, and the electromagnetic induction heating device can be heated by radiant heat. It is possible to reduce the insulation limit and improve durability.

In the above embodiment, the inner circumferential wall has a bottomed double cylindrical structure as the heat pipe structure of the evaporator, but the bottom surface of the inner circumferential wall may have a flat heat pipe structure. It is also possible to arrange the pipes appropriately.

In addition, in the above example, a gravity-type thermosiphon type heat pipe structure with a simple structure and reliable operation was used. It is okay to do so.

Furthermore, in the above embodiments, electromagnetic induction heating is performed using a high frequency method, but a low frequency method using commercial frequencies may also be used. In this case, for example, by increasing the number of windings of the induction coil and attaching a non-magnetic highly conductive material to the ferromagnetic material described above, the heat generation of the heated part can be increased and the heating efficiency can be increased. It is something. In addition to the spiral shape, the induction coil can be shaped into an annular coil or can be distributed in an appropriate number of shapes. Further, although the electromagnetic induction heating device itself does not generate heat, it can be hermetically housed in a box made of a non-magnetic material such as a stainless steel plate if necessary.

Additionally, 18 is commonly used for storage of waste solvents.
Although the description has been made regarding cans, the present invention can be similarly applied to general-purpose cans such as 20 cans, drum cans, and other solvent containers.

Note that the waste solvent may be directly charged into the evaporator and heated instead of being charged into the solvent container and heated.

As described above, in the present invention, not only can the heat generated by the heating source be efficiently transferred to the waste solvent by the evaporator having a heat pipe structure, but also the heat absorption part of the evaporator has a heat pipe structure. Since the evaporator itself is heated by induction, the evaporator itself can generate heat directly, reducing heat dissipation to the surrounding area and preventing unnecessary heating.Also, the heat absorption part of the heat pipe structure can be heated to the highest temperature, increasing heat transfer efficiency. This will save power, reduce solvent recovery time, and reduce the amount of time needed for solvent recovery.

[Brief explanation of the drawing]

FIG. 1 is a partially omitted vertical sectional view of one embodiment of the present invention, and FIG. 2 is a partially omitted partially sectional view of another embodiment of the invention. 2... Solvent container, 3... Evaporator, 5... Inner peripheral wall, 9... Heat pipe outer wall, 12... Electromagnetic induction heating device.

Claims (1)

[Scope of Claims] 1. The evaporator has a heat pipe structure so that waste solvent can be stored and evaporated and heated, and an electromagnetic induction heating device is disposed in the endothermic part of the heat pipe structure so as to perform induction heating. Evaporation equipment for solvent recovery. 2. The inner circumferential wall of the evaporator has a bottomed double cylindrical heat pipe structure, and the outer wall of the heat pipe on the outer surface of the inner circumferential wall is formed of a non-magnetic material, and a ferromagnetic material is arranged inside the bottom surface of the outer wall of the heat pipe. 2. The evaporator for solvent recovery according to claim 1, wherein the heat absorbing portion has a heat pipe structure. 3 The bottom surface of the inner circumferential wall of the evaporator has a flat heat pipe structure, the outer wall of the heat pipe on the outer surface of the inner circumferential wall is formed of a non-magnetic material, and a ferromagnetic material is arranged inside the outer wall of the heat pipe to form a heat pipe. The evaporator for solvent recovery according to claim 1, wherein the evaporator has a heat absorbing section. 4. Any one of claims 1 to 3, which is an evaporator having a heat pipe structure, in which a solvent storage container such as an 18 can or drum can for charging waste solvent is accommodated in and out of the evaporator. An evaporation device for solvent recovery as described in .