JPH1119625A - Vacuum evaporation separation recovering method and device therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To shorten the time required for treatment, to improve treatment capability, to reduce a running cost and to recover vaporized materials with high purity. SOLUTION: This method is to successively separate and recover the various vaporized materials by changing the degrees of vacuum within respective chambers while holding the internal temps. of vacuum evaporation chambers 15, 35 and 51 arranged in one or plural sets constant respectively. These degrees of vacuum are preferably changed by the operation of vacuum pumps and the supply of an inert gas and/or a reducing gas, and are normally changed within the range of 800 to 10<-5> Torr.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vacuum evaporation separation / recovery method in which a plated product, a mixture, a compound, a deposit and the like applied to the surface of a processed material are sequentially and efficiently evaporated and recovered in a vacuum. It concerns the device.

[0002]

2. Description of the Related Art For example, when zinc, nickel, lead, oil or their oxides plated on the surface of an automobile body, home appliances, computer-related equipment, various sludges or the like are recovered by vacuum heating, the conventional methods are used. In the vacuum heating method described above, since there is no convection heating, the rate of temperature rise from 0 to about 500 ° C. in the low temperature period is very slow. Therefore, when dezincing as much as 6,000 tons of scrap per month, Since the equipment specifications are large and the initial cost is high, there is no cost advantage and there is no practicality. In order to solve the above problem, it is conceivable to perform oxidative heating in a low temperature period and vacuum heating in an evaporation period. In this case, however, metal oxides are formed, so the vacuum evaporation temperature has to be raised, and In order to remove the plating, the temperature must be increased over time, which is disadvantageous in that there is no cost advantage as in the above case.

In order to solve such a problem, the inventor of the present invention puts a material to be vacuum-evaporated into a furnace having a heating means, and in a oxidizing atmosphere a predetermined temperature (0 to 180 ° C. at which oxidation does not occur). ), The temperature is maintained, and then the inside of the furnace is maintained at the designated evaporation temperature, and a vacuum is applied by a pressure reducing means. A vacuum evaporation separation / recovery method was proposed in which a plurality of recovery devices were connected to each other and condensed and recovered in the recovery device.
No. 16248).

[0004]

However, in the above-mentioned method, after the processing object is charged into the furnace, the degree of vacuum in the furnace is made constant and the temperature is raised at each evaporation temperature of the recovered material. A considerable amount of time is spent, leaving problems in terms of throughput and running costs. Further, in the case of heating in a vacuum state, the temperature rise in the central portion is very slow, the temperature distribution is poor, and the recovery purity is poor.

Accordingly, the present invention can further reduce the time required for processing as compared with the above-mentioned conventional improved method,
It is an object of the present invention to provide a vacuum evaporation separation / recovery method and apparatus capable of improving the processing capacity and reducing the running cost, and recovering the evaporated matter with high purity.

[0006]

SUMMARY OF THE INVENTION The present invention provides various types of evaporants by maintaining a constant temperature in one or more vacuum evaporation chambers and changing the degree of vacuum in each chamber. The above problem has been solved by a vacuum evaporation separation and recovery method characterized by sequentially separating and recovering. The degree of vacuum is preferably changed by operating a vacuum pump and supplying an inert gas and / or a reducing gas, and is usually changed in a range of 800 to 10 ^-5 Torr.

In the present invention, the temperature in the processing chamber is raised in advance. Since the temperature can be raised under a positive pressure or a normal pressure, convection heating and conduction heating by radiation can be used. The time required for warming can be significantly reduced. In the case of the conventional heating under a condition where the degree of decompression is high and convection does not occur, particularly 200
Although the temperature rise in the range of 500 ° C. was very slow and the temperature distribution was poor, as described above, in the case of the present invention, the temperature rise did not take much time and the temperature distribution was good.

Further, in the conventional method, convection does not occur even when the temperature is raised to the target temperature, so that the temperature distribution is poor and the purity of the evaporatively recovered substance is low. However, in the case of the present invention, the temperature distribution is low. Well, the purity of the evaporative recovery is high. Furthermore, since the decompression processing time to the target degree of vacuum is shorter than the heating processing time to the target temperature of the processed product, the method according to the present invention is more efficient than the conventional method. Processing capacity is high and running costs are low.

FIG. 3 is a graph showing this fact. The normal pressure of a processed material (steel scrap) having a size of 500 × 810 × 700 mm, a weight of 2367 kg and a depth of 350 mm as a temperature measurement depth at the center. (760 Torr), the surface temperature and the center temperature under vacuum (0.05 To
The transition of the surface temperature and the center temperature under rr) is shown over time (the horizontal axis represents the time required for temperature rise, and the vertical axis represents the temperature). The line (A) there is the surface temperature under normal pressure, the line (B) is the center temperature under normal pressure,
Line (C) is the surface temperature under vacuum, and line (D) is the center temperature under vacuum.

As is clear from this graph, the temperature rises to the inside in a shorter time under normal pressure than under vacuum, and the difference between the surface temperature and the center temperature is smaller (temperature Good distribution). For example, if the center temperature is 5
Although it takes 4 hours under vacuum to raise the temperature to 00 ° C., it takes only 2 and a half hours under normal pressure, and the difference between the surface temperature and the center temperature after 4 hours is as follows. It is about 300 ° C under vacuum, while about 100 ° C under normal pressure.
° C. From these facts, it is clear that the method according to the present invention in which the temperature is raised under normal pressure or positive pressure is more advantageous than the conventional method in which the temperature is raised under vacuum.

The following table compares the purity of recovered metals in the conventional method and the method according to the present invention. For example, in the conventional method, the degree of vacuum is 65 to 75 Torr.
While the purity of cadmium evaporated and recovered when the temperature is raised to 300 ° C. in the range of r is 87.6, in the method according to the present invention, the temperature is maintained at 650 ° C. and the degree of vacuum is 65 ° C. The purity of cadmium evaporated and recovered when it is changed to the range of ~ 75 Torr is 97.6, which is higher than that of the conventional method. Such a tendency is also observed at other temperatures.

[Table 1]

The present invention proposes a method in which dioxin is prevented from being regenerated from the residual gas by subjecting the processed material to vacuum evaporation, and the gas is rendered non-polluting and discharged. To this end, at least the vacuum-evaporation chamber arranged at the forefront stage is used to remove one processed product containing chloride.
Vacuum evaporation is performed in the range of 0 ^-1 to 10 ^-5 Torr.

In the present invention, preferably, in addition to the depressurizing action by the vacuum pump, an inert gas and / or
Alternatively, a reducing gas is supplied. This is because it is difficult to control the decompression value to a constant value by using a decompression control using only a vacuum pump, and an inert gas is supplied to assist the control.

Further, if the pressure is a reduced pressure of about 760 to 10 ^-5 Torr, if the oxides are remarkably decomposed and evaporated from the processing substance, oxidation in the processing chamber, oxidation of the processing substance, oxidation of the evaporation substance, etc. occur, and the recovery rate A number of problems occur, such as a decrease in recovery, a reduction in recovery purity, oxidation of residual processed products, and oxidative deterioration of components in the processing chamber. In order to avoid such a problem, in the present invention, when the degree of pressure reduction is low, a reducing gas is added to control the pressure reduction.

Further, in the present invention, when the powder is reduced and recovered as the separated and recovered product, a reduced gas and a reduced powder such as coke are mixed. The powder material collected by a bag filter, a cyclone device or the like is often very fine oxide. In the case of reducing and evaporating and recovering this fine oxidized substance under reduced pressure, the gas does not reach the central part with the reducing gas alone, the evaporation recovery rate is poor, and heavy metals remain in the residue. Can not be disposed of. In the present invention, in order to solve this problem, a powder reduced product such as coke is mixed and processed into a powder processed product so as to be uniform (the location where the gas around the center of the processed product is poor around the gas). Auxiliary reduction.), Reducing the reduction time and increasing the rate of evaporation and reduction of the reduced substance.

In these treatments, the mixture of the powder treatment and the powder reducing agent is subjected to a pressure reduction of 10 ⁻² to 10 ⁻⁵ Torr.
By treating at a temperature of 500 ° C. to 1300 ° C., good results can be obtained. Further, by mixing the powder of coke or the like with the solid of the processed powder, danger such as explosion can be avoided.

Further, the present invention relates to an apparatus constituted by connecting a plurality of vacuum evaporation chambers having different degrees of vacuum, wherein a passage chamber is interposed between the evaporation chambers, and the evaporation chamber and the passage chamber are connected to each other by L.
We propose a vacuum evaporation separation and recovery device characterized by being arranged in a letter shape.

When the vacuum evaporation chambers are connected linearly,
Due to the stroke, it is difficult to use a pusher mechanism using a cylinder to transport the processed product. However, when the product is arranged in an L-shape as described above, it can be used.
The configuration can be simplified. When the vacuum evaporation chambers are directly connected, it is difficult to adjust the pressure between the two evaporation chambers. However, in the present invention, since the pressure adjustment chamber is provided between the connected evaporation chambers, the pressure adjustment between the evaporation chambers is extremely difficult. It will be easier.

The pressure regulating chamber also serves to prevent the evaporant in the previous evaporation chamber from flowing into the next evaporation chamber. That is, since the temperature of the pressure control chamber is not raised, almost no evaporant precipitates and does not flow into the next chamber to lower the recovery purity of the evaporate. Further, since the evaporant precipitates, the vacuum sealability between the chambers is not hindered, and the aging of the seal is prevented.

Further, the apparatus according to the present invention is provided with a vacuum double door in which an airtight door is double arranged at the exhaust port of each evaporation chamber (double seal double door system). As a result, the vacuum sealability is improved, and even if the sealability of one door is poor, the sealability is maintained by the other door. With this vacuum double door, it is possible to collect the collected material during the temperature rise and to operate continuously (when the collected material is collected during the temperature rise, the collected material may burn, the vacuum furnace may be oxidized, Since the heat may damage the vacuum seal,
In the past, it was always collected after the temperature was lowered. ). Also,
Because of this vacuum double door, each evaporation chamber can be used not only as a vacuum evaporation chamber but also as a general atmosphere furnace or a steaming chamber.

[0021]

Embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a schematic configuration diagram of an apparatus according to the present invention for carrying out a method according to the present invention. In FIG. 1, reference numeral 1 denotes a carry-in apparatus for carrying a processed product 2 to be subjected to a vacuum evaporation process in the present apparatus; It is attached to the first transport device 3. A preheating furnace 5 provided with a stirrer (usually a fan) 4 is arranged in the middle of the first transporting device 3, and is supplied to the first transporting device 3 by the loading device 1 and transported.
Is preheated by passing through the preheating furnace 5.

The preheating furnace 5 heats the processed product 2 to a temperature at which the processed product 2 is not oxidized (usually 0 to 180 ° C.). The preheating furnace 5 is arranged at a stage preceding the vacuum evaporating chamber separately from a vacuum evaporation chamber described later. By doing so, the preheating furnace 5 can be a normal pressure furnace type without using a vacuum furnace type, and the manufacturing cost can be reduced to about one third. Further, by using the normal pressure furnace type, it becomes possible to provide facilities such as mesh belt conveyance which cannot be provided by the vacuum furnace type.

A second transfer device 8 extending in a direction orthogonal to the first transfer device 3 and reaching the vacuum purge chamber 7 is attached to the tip of the first transfer device 3. The second transfer device 8 is provided with a first cylinder 9 (usually an air cylinder) at a rear end thereof, and the processed product 2 on the second transfer device 8 is sent into the vacuum purge chamber 7 by the action. The vacuum purge chamber 7 is provided with a vacuum door 10 on the outside and a vacuum door 11 in the furnace on the inside. When the processing product 2 is carried in, the vacuum door 11 in the furnace is closed and the vacuum door 10 is opened. After the article 2 is carried in, the vacuum door 10 is also closed.

Numeral 12 denotes a device for recovering the evaporated substance in the vacuum purge chamber 7, which includes a booster pump 13 and a rotary.
The pump 14 is connected to the pump 14. The booster pump 13 and the rotary pump 14 are evacuated to a vacuum
The pressure in the vacuum chamber 7 is reduced to a level of the order of 10 ^-2 Torr, and then the pressure in the vacuum chamber 7 becomes substantially the same as that of the first evaporation chamber 15. Pressure is restored until A heat insulating door 16 is provided at a boundary between the vacuum purge chamber 7 and the first evaporation chamber 15. Usually, the vacuum purge chamber 7 and the first evaporation chamber 15 are arranged so as to have an L-shape.

When the inside of the vacuum purging chamber 7 and the inside of the first evaporating chamber 15 have the same pressure by the above operation, the in-furnace vacuum door 11 and the heat insulating door 16 are opened, and the processed article 2 is moved to the vacuum purging chamber. Then, the vacuum door 11 and the heat insulating door 16 in the furnace are closed. At the start of the operation, the first evaporating chamber 15 is set to a preset temperature and a preset vacuum degree in advance,
The degree of vacuum is adjusted while keeping the temperature constant (the same applies to each of the evaporation chambers described later).

In the first evaporating chamber 15, a metal recovery unit 18 and a powder recovery unit 19 are installed via a vacuum double door 17. Further, following the powder recovery device 19, the diffusion pump 2
0, a holding pump 21, a booster pump 22, and a rotary pump 23 are provided. The operation of the diffusion pump 20, the holding pump 21, the booster pump 22, and the rotary pump 23 controls the degree of vacuum in the first evaporation chamber 15 after the processing product 2 is fed.

FIG. 2 shows the configuration of the vacuum double door 17 (the same configuration is applied to the vacuum double door described later). A vacuum door chamber is provided between the exhaust port 91 of the evaporation chamber 15 and the exhaust pipe 92. A vacuum double door 17 is installed in the vacuum door chamber 93. The vacuum double door 17 is composed of two doors 96 fixed to a rod 95 of a cylinder 94 installed in the upper part of the vacuum door chamber 93 and moving up and down integrally. A packing 97 is provided in two upper and lower stages to achieve an airtight seal by slidingly contacting the inner wall surface of the chamber 93.

The vacuum double door 17 has such a simple structure, the construction cost and the equipment cost are low, and even if the sealing state of one of the two doors 96 is the convection heat in the evaporation chamber 15, For example, even if the door 96 becomes defective, there is an advantage that the seal of the other door 96 can secure the entire sealing property.
Further, since the vacuum door chamber 93 is relatively small, the absolute amount of the stains deposited in the chamber is small, and facility management such as cleaning is easy. Further, since the vacuum double door 17 is installed in the vicinity of the exhaust port, the vacuum pump side is closed and the exhaust port side is opened so that the vacuum evaporation chamber 15 can be used also as an atmosphere furnace or a steam furnace. It becomes possible. As described above, since the vacuum double door 17 is provided, by closing the same, the first evaporation chamber 1 is closed.
The evaporant can be recovered during the temperature rise in 5, and there is no time loss due to the temperature drop as in the conventional case.

The first evaporating chamber 15 contains a heater-2.
4 and a gas stirring device 25 are provided, and the temperature of the inside of the first evaporation chamber 15 is controlled by the action thereof. Metal evaporates that are heated by vacuum heating and evaporated in the first evaporating chamber 15 are collected by a metal recovery device 18, and powder evaporates are collected by a powder recovery device 19.

In some cases, the degree of vacuum in the vacuum purging chamber 7 and the first evaporating chamber 15 cannot be controlled by the pumps alone. In such a case, an inert gas (generally, nitrogen gas or argon gas) is used. And a reducing gas (generally hydrogen gas, carbon monoxide or NH ₃ decomposition gas) are supplied into the vacuum purge chamber 15. 26 is an inert gas cylinder, 27 is a reducing gas cylinder, and a gas line 28 extending from them is connected to the vacuum purge chamber 7 and the first evaporation chamber 15 via a vacuum valve. Reference numeral 29 denotes a second cylinder provided at the outer end of the first evaporation chamber 15.

At the outlet side of the first evaporation chamber 15, the insulated door 3 in the furnace is provided.
0 is installed, and a vacuum door 32 that opens and closes the inlet side of the first pressure adjustment chamber 31 is installed to face this. When the in-furnace heat insulating door 30 and the vacuum door 32 are opened, the second cylinder 29 transfers the processed product 2 in the first evaporating chamber 15 to the first pressure adjusting chamber 31.
Plays the role of pushing inside. Also in the first pressure adjustment chamber 31,
A third cylinder 33 for sending out the processed product 2 in the room is provided. The movement of the processed product in the first pressure adjustment chamber 31 is low.
It depends on the raster drive.

A second evaporating chamber 35 is connected to the first pressure adjusting chamber 31 via a vacuum door 34 and a heat insulating door 34a so as to have an L-shape. After the processing in the first evaporation chamber 15 is completed, the first pump is operated by the diffusion pump 20, the holding pump 21, the booster pump 22, and the rotary pump 23.
When the degree of vacuum in the evaporation chamber 15 and the first pressure regulating chamber 31 is adjusted, or when the degree of vacuum in both chambers becomes the same by opening the bypass solenoid valve (described later). The same applies between the evaporation chamber and the pressure adjustment chamber),
When the insulated door 30 and the vacuum door 32 are opened, the processing product 2 in the first evaporation chamber 15 is pushed into the first pressure adjustment chamber 31 by the action of the second cylinder 29. After pushing the processed product 2,
The furnace insulation door 30 and the vacuum door 32 are closed.

The second evaporating chamber 35 has substantially the same configuration as the first evaporating chamber 15, and includes a heater 36, a gas stirring device 37 and a fourth cylinder 38, and a metal recovery device 40 through a vacuum double door 39. And a powder recovery device 41 are provided. A diffusion pump 42 having a holding pump 43, a booster pump 44, and a rotary pump 45 are provided after the powder recovery device 41. And the insulated door 4 in the furnace
6. A second pressure adjusting chamber 48 is connected via a vacuum door 47.

The second pressure adjusting chamber 48 is provided in the first pressure adjusting chamber 31.
Similarly, a fifth cylinder 49 is provided, to which the vacuum door 5 is attached.
The third evaporating chamber 51 is connected via the heat insulating door 50a so as to have an L-shape. The third evaporating chamber 51 has substantially the same configuration as the above-described evaporating chamber, and includes a heater 52, a gas stirring device 53, and a sixth cylinder 54, and a vacuum double door 55.
, A metal recovery device 56 and a powder recovery device 57 are installed, and a diffusion pump 59 equipped with a holding pump 58, a booster pump 60, and a rotary pump 61 are installed. The insulated door 62 in the furnace and the vacuum door 6
A cooling chamber is connected via 3.

When the processed product 2 is sent into the first pressure adjustment chamber 31, the degree of vacuum in the second evaporation chamber 35 and the first
The degree of vacuum in the pressure adjustment chamber 31 is adjusted, and when both chambers have substantially the same pressure, the vacuum door 34 and the heat insulating door 34a are simultaneously opened. Then, the processed product 2 is pushed from the first pressure adjustment chamber 31 into the second evaporation chamber 35 by the action of the third cylinder 33,
After the completion of the pushing, the heat insulating door 34 is closed.

In the second evaporation chamber 35, the first evaporation chamber 1
Similarly to 5, the degree of vacuum is controlled by the action of the rotary pump 45 and the like, and the temperature is controlled by the heater 36. Further, if necessary, control by an inert gas, a reducing gas, or the like is performed. Is performed. Then, a metal evaporant that evaporates as a result of vacuum heating of the processed product 2 is collected by the metal recovery device 40, and powder oxide and the like generated at that time are recovered by the powder recovery device 41. When the degree of vacuum is 100 Torr or more, the rate of temperature rise of the processed product 2 is increased by a method such as convection heating by stirring with the gas stirring device 37.

After the processing in the second evaporation chamber 35 is completed, the operation of opening the bypass solenoid valve or the rotary pump 4
5. The degree of vacuum in the second evaporation chamber 35 and the second pressure adjustment chamber 48 is controlled by the operation of the booster pump 44, the diffusion pump 42, the holding pump 43 and the like. Next, the furnace heat insulating door 46 and the vacuum door 47 are opened, and the processed product 2 is pushed into the second pressure adjusting chamber 48 by the fourth cylinder 38, and then the furnace heat insulating door 46 and the vacuum door 47 are closed. The movement of the processed product 2 in the second pressure adjustment chamber 48 is performed by the cylinder 49.

When the processed product 2 is sent into the second pressure adjustment chamber 48 in this manner, the degree of vacuum in the third evaporation chamber 51 and the degree of vacuum in the second pressure adjustment chamber 48 are adjusted in the same manner as described above. Then, when both chambers have substantially the same pressure, the vacuum door 50 is opened. Then, the processed product 2 is pushed from the second pressure adjustment chamber 48 into the third evaporation chamber 51 by the action of the fifth cylinder 49, and after the pushing is completed, the vacuum door 50 and the heat insulating door 50a are closed.

In the third evaporation chamber 51, similarly to the first and second evaporation chambers 15, 35, a rotary pump 61 is provided.
The degree of vacuum is controlled by the action of, for example, the temperature is controlled by the heater 52, and the control by an inert gas, a reducing gas or the like is performed as necessary. Then, the metal evaporant that evaporates as a result of vacuum heating the processed product 2 is collected by the metal recovery device 5.
6 and powder oxides generated at that time are collected by a powder collecting device 57.

As described above, in the apparatus according to the present invention, the evaporation chambers 15, 35, 51, the vacuum purge chamber 7, and the pressure adjustment chambers 31, 48 are arranged in an L-shape. There are merits in product transportation. That is, when an air cylinder is used to move the processed product between the evaporation chambers, the stroke of the cylinder is usually only one evaporation chamber. Therefore, when the evaporation chambers are linearly connected, a plurality of cylinders are connected. It cannot work over the evaporation chamber. However,
Since the apparatus according to the present invention is arranged in an L-shape as described above, unloading of the processed product 2 from each of the evaporation chambers 15, 35, 51 is performed by the cylinders 2 installed in the respective evaporation chambers 15, 35, 51.
9, 38, 54, and the removal of the processed product 2 from the first and second pressure regulation chambers 31, 48 can be achieved by the cylinders 33, 49 installed in the respective chambers. Can be simplified.

A cooling chamber is connected to the third evaporation chamber 51.
This cooling chamber may be a single chamber, but it is preferable to provide a plurality of chambers in series in consideration of a situation where the cooling section is too short to sufficiently cool in the case of a large amount of processing or the like. In the illustrated example, the cooling chamber is divided into three chambers, a first cooling chamber 64, a second cooling chamber 65, and a third cooling chamber 66.
The chambers are separated by vacuum doors 67 and 68, respectively.

Each of the cooling chambers 64 to 66 is provided with a stirrer 69.
The first cooling chamber 64 includes a seventh cylinder 70. Reference numeral 71 in each cooling chamber indicates a cooling fin tube. Further, to each of the cooling chambers 64 to 66, a line from the inert gas cylinder 26 and the reducing gas cylinder 27 is connected via a double vacuum door 72, respectively, and a recovery device 73, a booster pump 74, and a The tally pump 75 is connected.

After the completion of the evaporation process in the third evaporation chamber 51,
Operation of the rotary pump 75 and the booster pump 74;
Or, when the pressure in the first cooling chamber 64 becomes substantially the same as the pressure in the third evaporation chamber 51 by opening the solenoid valve of the bypass,
The furnace heat insulating door 62 and the vacuum door 63 open. Then, when the processing product 2 is pushed into the first cooling chamber 64 by the operation of the seventh cylinder 54, the in-furnace heat insulating door 62 and the vacuum door 63 are closed.

Next, an inert gas is supplied from the inert gas cylinder 26 into the first cooling chamber 64 until the pressure in the chamber becomes about normal pressure, and the processed material 2 is rapidly cooled by stirring with the stirring device 69.
At that time, cooling water is passed through a cooling fin tube 71 extending into the room to accelerate the cooling speed. After cooling to the set temperature in this way, an inert gas is supplied into the second cooling chamber 65 at the same pressure as the first cooling chamber 64, or the operation of the rotary pump 75 and the booster pump 74, Alternatively, after controlling the pressure in the second cooling chamber 65 by opening the solenoid valve of the bypass, the vacuum door 67 is opened, and the processed product 2 is conveyed into the second cooling chamber 65 by roller driving. .

In the second cooling chamber 65, the same operation as in the first cooling chamber 64 is performed, and the processed product 2 is rapidly cooled. The heat exchange of the inert gas is performed between the cooling fin tube 71, the double vacuum door 72, and the water in the double cooling chamber. Here, the processed product 2 cooled to the set temperature is transported to the third cooling chamber 66 in the same manner as described above, and is further rapidly cooled in the same manner as described above.

When the processed product 2 is cooled to the set temperature, the vacuum door 76 outside the furnace is opened, and the processed product 2 is carried out of the cooling chamber by a roller drive. Thereafter, the out-of-furnace vacuum door 76 closes,
After the air is sucked into the cooling chamber 66 by a rotary pump 75 and a booster pump 74 to make the cooling chamber 66 a pressure of the order of 10 ^-2 Torr, an inert gas is introduced. The processed product 2 after the processing is sent to the processing reversing device 78 by the roller drive of the out-of-furnace transfer device 77, and is carried out of the furnace from there.

In the processing of metal-treated products including plastics and woods containing or not containing metals, the double vacuum doors 17, 39 and 55 are closed and the double vacuum doors 80 and 8 are closed.
8 (closed during the vacuum evaporation separation and recovery process), the first evaporating chamber 15, the second evaporating chamber 35 and the third evaporating chamber 51 are made into an atmosphere furnace or a steaming chamber, and plastic and wood containing metals are used. Put it in a steamed state.

In the case where the processed product 2 contains dioxin, a treatment for preventing its regeneration and converting it into a non-polluting gas is performed. That is, a gas heating device 81 is installed in the first evaporation chamber 15 and the second evaporation chamber 35 via the double vacuum door 80, where the first evaporation chamber 15 and the second evaporation chamber 3 are located.
5 is heated to about 1100 ° C.

Following the gas heating device 81, the neutralizing agent layer 82
Is provided with a gas neutralization layer 83 and a gas combustion chamber 84. The gas neutralization layer 83 is steam-cooled,
By passing the gas heated to 00 ° C. through it, it is cooled to room temperature in about 10 seconds, thereby preventing regeneration of dioxin and neutralizing treatment by the neutralizing agent layer 82. Next, the gas is sent to a gas combustion chamber 84, where it is burned, and then discharged through a cyclone 85 and a bag filter 86 as a pollution-free gas by a blower 87.

In each of the evaporation chambers 15, 35 and 51, a gas cooling chamber 90 having a liquid recovery tank 89 is installed via double vacuum doors 80 and 88, and when no dioxin is contained, the gas is cooled. When it is sent to the gas cooling chamber 90 and passes through it, a part of it is turned into oil by the cooling temperature and becomes liquid recovery tank 8.
Collected in 9 The gas that has not been turned into oil is gas neutralized layer 8
After being sent to 3 and neutralized, it is released in the same process as above.

Tables 2 and 3 show tests conducted to show that dioxin treatment can be effectively performed in the method and apparatus according to the present invention, that is, the steaming method under normal pressure and the vacuum heating according to the present invention. Depending on the method, 60
It shows the residue composition analysis values when treated at 0 ° C. and 800 ° C. (Table 2) and when the shredder dust is treated at 800 ° C. (Table 3).

[Table 2]

[Table 3]

According to the analysis values, the total amount of dioxin when the end-of-life vehicle was steamed at 600 ° C. was 0.404.
76.9 ng / n, whereas that in the case of vacuum heating is only 0.00017 ng / n.
The total amount of dioxin in the case of steaming at 0 ° C. is 0.3727 ng / n, whereas that in the case of vacuum heating is only 0.001521 ng / n (lower column in Table 2). Dioxin total amount when steamed at 800 ° C. is 23.405 ng /
n is 0 in the case of vacuum heating (lower column in Table 3). From this, it can be said that the dioxin treatment in the present invention is sufficiently satisfactory.

The following Tables 4 and 5 show the toxic equivalent concentration (TEQ), that is, the dioxin content in the waste gas. It can be seen that the total amount of dioxin gas shown in the lowermost column is smaller than that of the other cases in the case of vacuum processing. Thus, in the case of the method according to the present invention, the regeneration of dioxin is effectively prevented because, in the case of vacuum evaporation, the intermolecular distance for dioxin generation becomes too wide, and the opportunity for reaction is very large. It is presumed to be less.

[Table 4]

[Table 5]

The apparatus shown in FIG.
Although five and 51 are connected in series, a configuration in which the evaporation chamber 35 or the evaporation chambers 35 and 51 are omitted is also possible.

[0055]

The present invention is as described above, and the time required for processing is short to control the degree of vacuum in the processing chamber while keeping the temperature constant, so that the processing time is improved and the running cost is improved. This is very useful because it enables the cost to be reduced, and further enables the evaporant to be recovered with high purity.

According to the third and eighth aspects of the present invention, it is possible to easily control the reduced pressure value and to suppress the oxidation of the processed material and the evaporant in the processing chamber.

According to the fourth aspect of the present invention, the reduced gas and the reduced solid coexist by uniformly mixing and treating the reduced powder such as coke with the processed powder. Thus, there is an effect that the reduction time can be shortened and the rate of evaporation and recovery of the reduced substance can be increased.

According to the fifth and ninth aspects of the present invention, in the case where the processed product contains dioxin, it can be prevented from being regenerated by vacuum treatment, and can be discharged without pollution. effective.

According to the seventh aspect of the present invention, since a general cylinder can be used for transferring the processed material, there is an effect that the entire apparatus can be simplified and the cost can be reduced.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of an apparatus according to the present invention.

FIG. 2 is a diagram showing a configuration of a vacuum double door in the device according to the present invention.

FIG. 3 is a graph showing the time required for raising the temperature of the surface and the central portion of the processed material in the method according to the present invention and the conventional method.

[Explanation of symbols]

 5 Preheating furnace 7 Vacuum purge chamber 15 First evaporating chamber 17 Vacuum double door 18 Metal recovery unit 19 Powder recovery unit 20 Diffusion pump 21 Holden pump 22 Booster pump 23 Rotary pump 24 Heater Tar 26 Inert gas cylinder 27 Reducing gas cylinder 35 Second evaporation chamber 51 Third evaporation chamber 81 Gas heating device 83 Gas neutralization layer 84 Gas combustion chamber

[Procedure amendment]

[Submission date] November 13, 1997

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Table 4

[Correction method] Change

[Correction contents]

[Table 4]

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] Table 5

[Correction method] Change

[Correction contents]

[Table 5]

Claims (13)

[Claims] 1. A method in which one or a plurality of provided vacuum evaporation chambers are kept at a constant temperature, and various evaporates are sequentially separated and recovered by changing the degree of vacuum in each of the chambers. Vacuum evaporation separation and recovery method. 2. The vacuum evaporation separation and recovery method according to claim 1, wherein the degree of vacuum is changed within a range of 800 to 10 ^-5 Torr while keeping the temperature constant. 3. The operation of a vacuum pump, wherein the change in the degree of vacuum is
3. The vacuum evaporation separation and recovery method according to claim 1, wherein the method is performed by supplying an inert gas and / or a reducing gas. 4. The vacuum evaporation separation and recovery method according to claim 1, wherein, when the powder is recovered as the separated and recovered material, a reduced gas and a reduced powder such as coke are mixed. 5. At least in the vacuum evaporation chamber disposed at the forefront stage, a treated product containing a chloride is treated at 10 ^-1 to 10 ^-5.
The vacuum evaporation separation and recovery method according to any one of claims 1 to 4, wherein the generation of dioxin and other toxic chlorides can be suppressed by performing a vacuum evaporation treatment in the range of Torr. 6. One or a plurality of vacuum evaporation chambers having means for raising the temperature of a room under normal pressure or positive pressure, and means for controlling the degree of vacuum in the room while maintaining a set temperature. Characteristic vacuum evaporation separation and recovery equipment. 7. The apparatus according to claim 6, wherein a plurality of vacuum evaporation chambers having different degrees of vacuum are connected in series, and a pressure adjustment chamber is interposed between the evaporation chambers, and the evaporation chamber and the pressure adjustment chamber. And a vacuum evaporation separation / recovery device, wherein the devices are arranged in an L-shape. 8. The vacuum evaporation separation and recovery apparatus according to claim 6, wherein said vacuum degree control means is a vacuum pump and a supply means of an inert gas and / or a reducing gas. 9. A means for heating an evaporative gas generated in at least the vacuum evaporation chamber disposed at the forefront stage, and a gas neutralizer for cooling while neutralizing the evaporative gas heated by the heating means. The vacuum evaporative separation / recovery apparatus according to any one of claims 6 to 8, further comprising: means for burning the gas neutralized by the gas neutralizing means. 10. A vacuum double door in which an airtight door is double arranged at an exhaust port of the evaporation chamber.
The vacuum evaporation separation and recovery device according to any one of the above. 11. A preheating furnace for preheating a treated product so as not to oxidize a treated product is provided in front of the foremost evaporating chamber at a distance from the evaporating chamber without being directly connected to the evaporating chamber. A vacuum evaporation separation and recovery apparatus according to any one of the above. 12. The vacuum evaporation separation and recovery apparatus according to claim 6, further comprising a plurality of cooling chambers for cooling the processed material subjected to the vacuum evaporation separation and recovery processing over time. 13. The vacuum evaporation separation / recovery device according to claim 6, wherein a powder recovery device is installed in the vacuum evaporation chamber together with a metal recovery device.