JP3149284B2 - Vacuum evaporation recovery method and apparatus - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for efficiently evaporating a plated product, a solid, a mixture, a liquid mixture, a shredder product, a powder, a granule, etc. applied to the surface of an object to be processed in a vacuum (hereinafter referred to as "evaporation"). The present invention relates to a method and an apparatus for vacuum evaporation recovery using a screw conveyor which collects by vacuum evaporation.

[0002]

2. Description of the Related Art Dalai powder, oil of cutting waste, water,
In addition, when removing zinc, nickel, and the like plated on the surface of an automobile body by vacuum evaporation, the rate of temperature rise in a low temperature period in a vacuum furnace has been remarkably increased because conventionally, only radiant heating was performed. It was late. Therefore, in the case of performing a large amount of processing, it is necessary to increase the equipment specifications or to prepare a number of equipments, so that initial costs and running costs are extremely high, and there is a problem that cost merit is lost.

[0003]

As described above, small articles such as powders, shredders, and granules have a problem that when heated in a vacuum furnace, the rate of temperature rise is slow and there is no cost advantage. Was. Then, an object of the present invention is to provide a vacuum evaporation recovery method and an apparatus which do not have such a problem.

[0004]

According to the present invention, a vacuum heating chamber into which an object to be processed is charged is depressurized and then heated.
In a vacuum evaporation and recovery method for condensing and solidifying an evaporant that evaporates in vacuum from the surface of the object to be collected and recovered, the object to be processed, which has been charged into a vacuum-replaced inlet-side vacuum replacement chamber, is depressurized from the inlet-side vacuum replacement chamber. Further, after being further charged into a heated vacuum heating chamber and collecting the evaporant that evaporates from the surface in the process of transferring the object to be processed to the outlet side by a screw conveyor installed in the vacuum heating chamber, A vacuum evaporation and recovery method characterized in that the object to be treated is taken out from the vacuum-exchanged outlet-side vacuum substitution chamber, and a vacuum heating chamber equipped with a decompression device that can be sealed and covered with a heat insulating material, On the inlet side and the outlet side, a vacuum replacement chamber equipped with an airtight door for the vacuum heating chamber and capable of reducing the pressure inside is installed, and the evaporant generated in the vacuum heating chamber is solidified and solidified. The recovery device deployed, also screw into the internal space of the vacuum heating chamber while a heating unit at the inner wall of the vacuum heating chamber - has solved the above problems with a vacuum evaporator and recovery device, formed by installing a conveyor.

[0005]

[Work] Since the objects to be treated put into the vacuum heating chamber are heated while being mixed with the rotation of the screw conveyor, the objects to be treated are heated uniformly and quickly, and the heating efficiency is good.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a longitudinal sectional view of an apparatus suitable for carrying out the method according to the present invention, and FIG. 2 is a side view thereof. In the drawing, reference numeral 1 denotes a sealable, usually cylindrical vacuum heating chamber, which has a sealable inlet side vacuum replacement chamber 2 and an outlet side vacuum replacement at one end (inlet side) upper surface and the other end (outlet side) lower surface. Room 3 is installed. Each of the vacuum replacement chambers 2 and 3 is provided with a decompression device 4, 5 respectively.
It has.

The vacuum heating chamber 1 is formed by covering a cylindrical inner retort 6 with a heat insulating material 7 while maintaining a gap, and a heating means 8 such as a resistance heater is provided in the gap. The object to be processed 22 put into the vacuum heating chamber 1 is heated by the heating means 8 from the outside.

Reference numeral 9 denotes a screw conveyor inserted into the inner retort 6 of the vacuum heating chamber 1, which is rotatably supported on both sides of the vacuum heating chamber 1. Reference numeral 10 denotes a rotary driving device such as a motor for driving the screw conveyor to rotate, and is disposed outside the vacuum heating chamber 1. This screw conveyor 9
In the case where there is, the object to be processed 22 is well mixed and uniformly processed at the time of rotation, and heat flow is improved, so that the rate of temperature rise is also increased.

Reference numeral 11 denotes a charging port for an object to be processed, which is formed above the one end (inlet side) of the vacuum heating chamber 1 so as to pass through the outer retort 12 and communicate with the chamber. Room 2 is installed. Input port 1 of inlet side vacuum replacement chamber 2
An airtight door 13a is provided at one connection portion, and an airtight door 13b for supplying an object to be processed is provided at an upper portion. A discharge port 14 is provided below the other end (outlet side) of the vacuum heating chamber 1 so as to pass through the outer retort 12 and communicate with the inside of the chamber. Is installed.
The airtight door 1 is also connected to the outlet 14 connection portion of the outlet side vacuum replacement chamber 3.
5 are deployed.

A heat exchanger 16 having a fan 17 is connected to the outlet side vacuum replacement chamber 3, and a cooling gas is circulated through the outlet side vacuum replacement chamber 3 to be discharged from the vacuum heating chamber 1 into the replacement chamber. The object to be heated is cooled without oxidation. The heat exchanger 16 and the fan 17 may be incorporated in the outlet side vacuum replacement chamber 3 in some cases. Reference numeral 18 denotes a discharge door provided in the outlet-side vacuum replacement chamber 3, which is opened to discharge the cooled workpiece.

Reference numeral 19 denotes an evaporant recovery port formed so as to penetrate the retort 12 outside the vacuum heating chamber 1 and communicate with the chamber.
The collection device 20 is connected to it. The recovery device 20 includes a decompression device 21.
By reducing the pressure in the vacuum chamber 0, the vacuum evaporant generated in the vacuum heating chamber 1 is recovered through the evaporate recovery port 19.

Next, a procedure for processing an object to be processed using the apparatus having the above configuration will be described in order. a. The insides of the vacuum heating chamber 1 and the inlet-side vacuum replacement chamber 2 are depressurized by the decompression devices 21 and 4, respectively. b. The inside of the vacuum heating chamber 1 is heated by the heating means 8 to raise the temperature. c. The supply airtight door 13b of the inlet side vacuum replacement chamber 2 is opened. d. The workpiece 22 is charged into the inlet-side vacuum replacement chamber 2. e. After closing the airtight door 13b, the pressure in the inlet side vacuum replacement chamber 2 is reduced by the pressure reducing device 4.

F. The hermetic door 13a of the inlet side vacuum replacement chamber 2 is opened, and after the object 22 is dropped into the vacuum heating chamber 1, the hermetic door 13a is closed. g. Starting the rotation drive device 10 and screw conveyor 9
Is rotated to gradually transfer the processing object 22 to the outlet side while mixing. h. The object to be processed 22 is continuously heated by the heating means 8 while being transferred by the screw conveyor 9, and as a result, the temperature is raised and the deposits on the surface are evaporated in vacuum. This vacuum evaporate is collected by the collection device 20 and condensed and solidified. i. When the workpiece 22 reaches the workpiece outlet 14, the workpiece 22 is dropped into the replacement chamber by using the airtight door 15 of the outlet side vacuum replacement chamber 3, and then the airtight door 15 is closed again.

J. The workpiece 22 that has fallen into the outlet side vacuum replacement chamber 3 is cooled by the cooling gas supplied from the heat exchanger 16 by the fan 17. k. After the cooled workpiece 22 is taken out by opening the discharge door 18, the discharge door 18 is closed, and the pressure in the outlet side vacuum replacement chamber 3 is reduced by the pressure reducing device 5. l. The above steps are repeated.

When a test for confirming the effectiveness of the method according to the present invention was performed under the following conditions, the results shown in FIG. 3 were obtained. Degree of vacuum 5 × 10 ^-3 Torr Workpiece 150Kg Electric quantity 70Kw Temperature measuring point Workpiece center Outer retort dimensions Inner diameter 600mm, length 2000m
m

A curve A in FIG. 3 shows a heating curve when the object to be processed is heated from inside and outside by rotating the screw conveyor 9 by the method according to the present invention, and a curve B shows the conventional surface heating only. FIG. 3 shows a heating curve in such a case. As is clear from this graph, it was confirmed that when the method according to the present invention was used, the temperature rise was faster for 3 to 4 and a half hours as compared with the conventional method.

[0017]

As described above, the present invention is capable of performing non-oxidizing treatment of an object to be processed, heating and raising the temperature quickly and efficiently, improving the processing capacity and reducing the running cost. It is very useful because it can recycle waste and reuse the recovered evaporates such as zinc, oil and water, and can also solve environmental problems caused by industrial waste.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a configuration example of an apparatus for performing a method according to the present invention.

FIG. 2 is a side view of the device shown in FIG.

FIG. 3 is a graph showing test results of a heating rate of an object to be processed;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Vacuum heating chamber 2 Inlet side vacuum replacement chamber 3 Outlet side vacuum replacement chamber 4 Decompression device 5 Decompression device 6 Inner retort 7 Insulation material 8 Heating means 9 Screw conveyor 10 Rotary drive device 11 Processing object inlet 12 Outer retort 13a Airtight Door 13b Airtight door 14 Workpiece discharge port 15 Airtight door 16 Heat exchanger 17 Fan 18 Discharge door 19 Evaporated matter recovery port 20 Recovery device 21 Decompression device 22 Workpiece

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁷ , DB name) F26B 5/04

Claims (2)

(57) [Claims] In a vacuum evaporation and recovery method in which a vacuum heating chamber into which an object to be processed is charged is depressurized and then heated to condense and solidify an evaporant that evaporates from the surface of the object to be vacuum-recovered, vacuum replacement is performed. The object to be processed, which has been charged into the inlet-side vacuum replacement chamber, was further charged from the inlet-side vacuum replacement chamber into a vacuum heating chamber in a depressurized and heated state, and the object to be processed was set in the vacuum heating chamber. A vacuum evaporation and recovery method, wherein after evaporating the material that evaporates under vacuum from the surface during the transfer to the outlet side by a screw conveyor, the object to be processed is taken out of the vacuum-replaced chamber on the outlet side. 2. A vacuum heating chamber, which can be hermetically sealed and covered with a heat insulating material and provided with a decompression device, is provided on its inlet side and outlet side.
Each of the vacuum heating chambers is provided with an airtight door and a vacuum replacement chamber capable of decompressing the inside is provided, and a recovery device for condensing and solidifying the evaporant generated in the vacuum heating chamber is provided. A vacuum evaporation and recovery apparatus comprising a heating means disposed on an inner wall and a screw conveyor provided in an internal space of the vacuum heating chamber.