DE2449303A1 - PROCESS FOR CONTINUOUS SEPARATION AND RECOVERY OF HALOGEN-SUBSTITUTED INSULATING MATERIAL FROM WASTE INSULATED WIRE MATERIAL - Google Patents

Description

Process for the continuous separation and recovery of halogen-substituted-in Insulation material made from scrap of insulated wire material.

"The trfindung a process for continuously separating and recovering relates lialogen-substituted insulation material from waste insulated wire material by dissolving the lialogensubstituierten insulating material with a solvent and Ao separate thereof the undissolved insulating material and the metal parts of the dissolved insulation material without chemical change.

Ls are the most diverse methods for separating insulation material of waste from insulated wires has become known. These methods are based essentially on;

1.) mechanical separation, e.g. by scouring, rubbing or by unwinding;

2.) thermal separation, e.g. by incinerating the waste with destruction of the insulation material or the use of low temperatures to make the insulation material brittle, before it is separated mechanically and

3.) the chemical removal of the insulation material.

For example, it is known from US Pat. No. 3,226,815 for removal of insulation material from wire scraps is fed to a manually controlled stripping device with movable cutting claws use. It is also disclosed in U.S. Patents 3,507,425 and 2,956,717 known mechanical and thermal measures for removal Combine small sections of the insulation material "by first removing the part of the wire from which the insulation material is separated is to be cooled to a low temperature, whereupon the cooled insulation material facing each other

ÖAD ORIGINAL

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standing cutting knives are attached. From U.S. Patent 3,035,454 for example, is also a high tenacity process for the destruction of the insulation material known, oei which the organic Isolation material of the effect of a stream of hot; Nitrogen gas is exposed, causing a depolymerization of the insulating material he follows. From US Pat. No. 3,331,718 there is also a method for removing certain sections of Kan-shaped Insulation materials of Draiitmaterials known at which the selected districts with a chemical reactant. are brought into contact with removal of a film-forming insulation material.

Although the aforementioned known method for the Linzelfall may be suitable, it has been shown that none of these known Process for continuous separation and recovery of large amounts of insulation material and metal is suitable. In fact, it has been shown that the known processes mentioned Have disadvantages, which can be summarized as follows:

1.) There is a chemical change in the insulation material, why it cannot be used again;

2.) chemicals are introduced into the recovered metals, which adversely affect the usual known metal finishing processes can affect;

3.) the procedures cause comparatively high costs and

4.) the processes cause smoke formation; it becomes hydrogen chloride produced, furthermore ashes and the like, which either have to be removed or directly into the atmosphere below Contamination of the same can be drained.

The object of the invention was therefore to provide a process for continuous Separation and recovery of halogen-substituted insulation material from waste of insulated wire material to be reported,

ORlQMAL 50981 8/0307

which can be carried out easily and advantageously and not only enables the production of halogen-substituted insulation material, but aucii enables the metal conductor to be recovered without in the process, the problem parts of the known processes occur.

The invention relates to a process for the continuous separation and recovery of halogen-substituted insulation material from scrap of insulated wire material by dissolving the thermoplastic halogen-substituted insulation material with a solvent and separating the undissolved insulation material as well as the metal parts of the dissolved insulation material without chemical change of the same, which is characterized by this is that one

a) the halogen-substituted insulation material of the wire waste in a countercurrent extractor with an outlet for the solution of the dissolved insulation material and an outlet for the undissolved solid constituents of the insulation material by continuously bringing the waste into contact with a countercurrent organic solvent for the halogen-substituted insulation material Temperature from 20 to 183 ⁰ C "solves that one

b) the resulting solution of the halogen-substituted insulation material withdraws from one outlet of the extractor and removes the undissolved parts of the insulation material and the metal waste discharges the second outlet and introduces it into a washing chamber, in which the undissolved parts of the insulation material 'and the metal waste are brought into contact with countercurrently introduced water with removal of organic solvent and that he

c) from the solution of the halogen-substituted insulation material separating the organic solvent and isolating the solvent for reuse.

The method of the invention can thus be carried out in a conventional manner will:

ORIGINAL BATHROOM 509818/0307

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The halogen-substituted insulation material of the wire waste is first dissolved in an organic solvent at elevated temperature and the remaining metal and undissolved Isolation material is separated. The solution of the halogenated insulation material can then be advantageous Way, either centrifuged or filtered. The solution of the halogen-substituted insulation material can then either be subjected to a spray drying process or dried and fragmented in a conventional manner Separation of the insulation material from the solvent. The recovered halogenated insulation material can then be removed and re-used, for example in an extrusion coating process. Furthermore, the isolated solvent can be recycled for further use.

The recovered insulation material can, for example, be reused in a device for the extrusion coating of wires, i.e. for the insulation of wires. The method of the invention also enables more valuable recovery Metals from wire scraps, whereby the metal can be recovered without burning off the insulation material and without formation hydrogen chloride, smoke, ash and the like polluting the air. The method of the invention thereby enables the recovery of ilalogen-substituted Insulation material and metal without chemical change, neither of the halogen-substituted insulation material nor of the metal.

Common wastes can be used to carry out the method of the invention can be used, whereby the wire scraps can consist of small fragmented particles.

The method according to the invention can, for example, be used in a plant can be carried out as shown in the attached flow diagram. From this flow diagram it follows that the to be worked up Waste from insulation material and metal parts are first brought into contact with a solvent that the halogen-substituted

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tuierte insulation material dissolved from the solvent and the solution filtered and removed for impurities and undissolved Components is centrifuged, whereupon the halogen-substituted Solution containing insulation material is dried or worked up and the recovered, halogen-substituted Isolation material is removed and the isolated solvent is recycled for reuse.

To carry out the process of the invention, the usually Accruing waste from fie tall parts and insulation material are used, such as shredded wire waste, which from a conductive metal, for example aluminum, an aluminum alloy, copper, a copper alloy and the like as well as an insulation material made of, for example, polyvinyl chloride, Copolymerizing Vinyl Chloride, Polyethylene, Polypropylene, Polyamides such as nylon, Teflon and other polymeric materials.

According to the flow diagram shown in the drawing, the Waste material introduced into the extractor 12> in which it is brought into contact in countercurrent with a solvent preheated to 20 to 183, for example to 177 ° C, whereby the halogen-substituted insulating material is dissolved. The insoluble solids are then placed in the wash chamber 13 transferred, in which it is brought into contact with water in countercurrent which is to be achieved that the organic solvent still adhering to the insoluble solid constituents Will get removed. The insoluble solids, e.g. polypropylene, polyethylene, copper and aluminum, are then in a liquid separator 14 transferred, in which residual Solvent and water are separated from the solid components. . ·

The solvent-water stream with, for example, 5 to 20 % solvent from the washing chamber 13 is then pumped into the tank 21.

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The solid substances withdrawn from the washing chamber 13 consist to a high percentage of metal and practically contain no more chlorides. The material therefore represents an excellent one. The starting material for charging metal recovery furnaces. On the other hand, however, the material can also initially be a Be subjected to pyrolysis before it is processed into metal.

The solution of solvent and halogen-substituted insulation material with a content of Ilalogen-substituted insulation material of for example 0.01 to 25 ° s, for example 1.0 to 25 %, is then pumped through a series filter system 15 with a coarse filter, which is present Metal particles filtered off and other particles of insoluble solids. Smaller particles are filtered off by the arrangement of a fine filter. The material filtered off by the filter system can then be fed to a metal recovery furnace or else be recycled in the extractor 12. The solution of the halogen-substituted insulation material is pumped into the tank 16, from which the preheater 17 is fed. The mixture of halo-substituted iso ^ lationsmaterial and solvent in the T <16 ank a homogeneous solution is maintained at about 38 ⁰ C by passing the solution is continuously circulated through a heater tank in this shape. In the preheater .17, the solution is then heated to about 4S ⁰ C, after which it is fed to an evaporator 18 which is operated for example at a pressure of 0.2 to 0.9 atmospheres and at a temperature of 32-149 ⁰ C. . The solids accumulating in the evaporator (nominal solids content 99 %) leave the evaporator in a practically dry state through an outlet. Conveniently, the solids are pumped out by means of a pump 24, preferably a Moynotype pump. In an advantageous manner, a tank 25 (slops tank) can also be provided, specifically for the purpose of use during commissioning and for flushing out the evaporator.

The solvent vapors with a content of about 1 liter of water are

which is condensed and then pumped to the solvent feed tank 20 and the pure solvent tank 11. In general, the flow between the two tanks is split 50:50. The water absorbed by the scrap metal insulation mixture or the water absorbed during the process is removed in the solvent tower 19. The 1 % water in the solvent stream is mixed with the stream withdrawn overhead from the water tower 22 (e.g. 4.1 to 7.1 % water), with a mixture of approximately 3.9 % water being fed to the solvent tower 19

2 is obtained. This material is then worked up, for example in an 8 kg / cm tower, to produce a product solvent which is withdrawn from the bottom of the tower with a content of about 0.32% V.wasser. The solvent is then cycled into the pure solvent storage tank 11.

The solvent-water wash stream (with e.g. about 9i> solvent) is mixed with the solvent withdrawn overhead from the solvent tank with e.g. about 11.7% water in the water tower feed tank 21, resulting in a Lin feed mixture for the water tower 22 of about 84.5 % Water yields.

The water tower 22 is operated at a pressure of, for example, one atmosphere and provides water as a product which contains about 0.043 % solvent and which is drawn off from the bottom of the tower. This water is then pumped into the pure water storage tank 23. The solvent with, for example, 4.1 to 7.1 % water drawn off overhead from the water tank 22 is then pumped into the solvent feed tank 20.

The method of the invention enables a practically complete one Recovery of halogen-substituted ionic material as well Metal from the wastes used to carry out the process of the invention, which is used to carry out the process used solvents can always be reused in a recycling process. Using the example of the flow diagram The method explained can of course be modified in the most varied of ways.

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A wide variety of conventional solvents can be used to carry out the process of the invention. Especially the following are advantageously used: tetrahydrofuran, methyl ethyl ketone, Methyl butyl ketone, dimethylformamide, dimethylacetamide, Toluene, petroleum ether, acetone, N-methylpyrrole, I-lethylene chloride and Mixtures thereof. Tetrahydrofuran, N-methylpyrrole, ethyl ethyl ketone, methyl butyl ketone, Dimethylformamide, dimethylacetamide, toluene and Proven methylene chloride. The solvents can be used alone or in combination with one another at temperatures up to the boiling point of the solvent or solvent mixture provided that the temperature does not exceed the decomposition temperature or the degradation temperature of the insulation material to be recovered.

The method of the invention does not need to be moisture-free Atmosphere.

The method according to the invention can be modified in various ways or modified. For example, the solution can be dried or separated from halogen-substituted isolating material and solvents can be carried out in a thin / wipe film evaporator, or else with the same Success using a spray drying process or using a steam atomizer.

example

Crushed wire waste, consisting of metallic copper, polyvinyl chloride, polyethylene, cross-linked polyethylene, polyamide (nylon), polypropylene and textile material was introduced into a countercurrent extractor of the Gifford-Wood type and brought into contact ^{with tetrahydrofuran at a temperature of 31 ° C in countercurrent in the extractor} . The heated tetrahydrofuran was continuously fed into the extractor in the vicinity of the outlet opening for the undissolved solid constituents, as was in turn in the vicinity of the inlet opening for the waste material to be processed.

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The polyvinyl chloride-tetrahydrofuran solution was filtered using a coarse filter (Cuno type) and then through a series of fine 25 micron polypropylene filters for fine filtration. The filtered polyvinyl chloride-tetrahydrofuran solution was then ^{heated to 49 °} C. and introduced into a thin-film evaporator of the type known from US Pat. No. 3,348,600, from which dry fragmented polyvinyl chloride and clean, clear tetrahydrofuran are drawn off.

The withdrawn tetrahydrofuran was over a standard distillation device recycled for reuse in the extractor, as well as the water wash solution used for washing the undissolved solids was used. The recovered polyvinyl chloride was then used for reuse in the Packaged as part of an extrusion coating process. Further the undissolved solids were used for metal recovery purposes packed in a metal recovery furnace.

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Claims (4)

2U9303 -Ί0-claimsclie 1. Process for the continuous separation and recovery of halogen-substituted Insulation material from scraps of insulated wire material by dissolving the halogen-substituted insulation material with a solvent and separating the undissolved Insulation material as well as the metal parts of the dissolved insulation material without chemical change of the same, characterized in that, that he a) the halogen-substituted insulation material of the wire waste in a countercurrent extractor with an outlet for the solution of the dissolved insulation material and an outlet for the undissolved solid components by continuously bringing the waste into contact with a countercurrent organic solvent for the halogen-substituted insulation material at a temperature of 20 to 183 ⁰ C solves that one b) the resulting solution of the halogen-substituted insulation material from one outlet of the extractor and withdraws the undissolved parts of the insulation material and the metallic waste discharges from the second outlet and introduces it into a washing chamber, in which the undissolved parts of the insulation material and the Metal scraps are brought into contact with countercurrent water with removal of organic solvents 'and that one c) separating the organic solvent from the solution of the halogen-substituted insulation material and isolating the solvent for the purpose of reuse. 2. The method according to claim 1, characterized in that one dissolves in step a) from the waste of insulated wire material polyvinyl chloride or a copolymer of vinyl chloride. 509818/0307 - S. -
■ * M * 3. The method according to claim 1, characterized in that the organic solvent methyl ethyl ketone, methyl butyl ketone, Dimethylformamide, dimethylacetamide, tetrahydrofuran, toluene, methylene chloride, petroleum ether, acetone, N-methylpyrrole or mixtures used hereof. 4. The method according to claim 1, characterized in that a solution of halogen-substituted insulation material is withdrawn from the extractor, which contains 0.01 to 25 VoI.- ⁰ * of halogen-substituted insulation material. 5 |. Process according to Claims 1 to 4, characterized in that one the solution of halogen-substituted insulation material obtained in step 1 filtered before further processing. Process according to one of Claims 1 to 4, characterized by the additional process step of centrifuging the solution the halogen-substituted insulation material. Process according to one of Claims 1 to 4, characterized in that the halogen-substituted insulation material is obtained from the solution of the halogen-substituted insulation material by evaporating the solvent in a thin-film evaporator which is operated at a pressure of about 0.2 to about 0, 9 atmospheres and at a temperature of about 32 to 149 ⁰ C is operated. B \ A method according to claim 1, characterized in that the solution of the halogen-substituted insulating material, which is removed from the extractor, from about 0.01 or 1.01 to 14.6 parts by volume of I contains halogen-substituted insulation material. Process according to Claim 1, characterized in that the solution of the halogen-substituted insulation material is used for the purpose of removal insoluble constituents is filtered and that the filtered solution is heated to a temperature of about 49 ° C. 509818/0307 Blank page