JPS61238929A - Recovering method for aluminum - Google Patents

Abstract

PURPOSE:To separate Al from paper without changing the properties of Al and to recover Al in the high yield by cutting finely an Al foil sheet pasted with an Al foil and paper, introducing it in the inside of a cylindrical screen and beating it with a high-velocity rotary knife. CONSTITUTION:A cutting wastage of an Al foil sheet which is used as a wrapping paper and pasted with the Al foil and paper or a spent Al foil sheet is cut in several mm breadth. The finely cut piece is introduced in the inside of a vertical cylindrical screen of a crushing granulator and a blade-shaped rotary knife of the inside part is rotated in about 2,000rpm to beat the fine piece of the Al foil sheet. Al is separated from the paper and beaten on the inside wall of the screen with the centrifugal force and made to a granule having a spherical or an irregular shape and discharged together with the paper powder through the small holes of the screen. The Al granule is separated from the paper powder by sieving these with a rotary sieve. Since a combustion method and the use of a reagent are not adopted in the removal of the paper, Al can be recovered in high yield without changing the properties thereof.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method for effectively recovering aluminum from cut scraps, used scraps, etc. of aluminum foil paper used for packaging and the like.

Conventional technology Aluminum foil paper, which is made by laminating aluminum foil and paper, has been widely used for various packaging purposes. A large amount of waste products such as scraps are generated. Therefore, from the standpoint of effective resource utilization, it is desired to effectively recover aluminum from these waste products.

Conventionally, the common method for separating and recovering aluminum from aluminum foil paper has been to incinerate these scraps, burn the paper, and recover aluminum. However, implementing this incineration method requires a large amount of thermal energy, requires a large amount of equipment investment for exhaust, dust prevention, etc., and the aluminum oxidizes during incineration, reducing recovery efficiency. There are drawbacks such as low purity of recovered aluminum because carbon generated by burning paper adheres to aluminum. Therefore, various methods have recently been developed, such as a method of separating aluminum by treatment with chemicals, and a method of disintegrating paper and aluminum by applying mechanical stirring in water.

As a representative example of the method of treatment with the above-mentioned drug, Patent No. 10
There is one disclosed in '76152 (see Japanese Patent Publication No. 515-18058). In this method, shredded aluminum foil paper is immersed in a 10-30% nitric acid solution and stirred to separate aluminum and paper.

Further, a representative example of a method of stirring and disintegrating in water is disclosed in Japanese Patent No. 1155444 (see Japanese Patent Publication No. 57-45815).

This method uses aluminum foil paper with water in a pulper (
The fibers of valves, waste paper, etc. are fed into a machine that loosens them, and the fibers are agitated and disintegrated using rotating blades.

Problems to be Solved by the Invention Among the conventional methods of recovering aluminum from aluminum foil paper as described above, the method of treating with chemicals not only requires a large investment in equipment to prevent pollution caused by waste liquid and gas, but also
It is technically difficult to separate only aluminum from the mixture after chemical treatment, and it is still necessary to heat the chemical solution to accelerate separation, wash with water and dry after separation, etc. The disadvantage is that the cost is extremely high.

However, the underwater agitation and disintegration method using a pulper requires a large amount of equipment cost and energy for post-disintegration processing, that is, dust removal, dehydration, drying, etc., and the processing water becomes white water containing paper fibers, making it difficult to use. There are drawbacks such as the need for processing equipment.

The present invention eliminates all the drawbacks of the conventional collection methods as described above, and effectively converts aluminum from aluminum foil paper waste at low cost without incineration, without using any chemicals or water, and without causing pollution. The aim is to provide a method for recovering waste.

Means for Solving the Problems In the aluminum recovery method of the present invention, aluminum foil paper, which is made by bonding aluminum foil and paper, is shredded into small pieces and then charged into a cylindrical jar or screen having a large number of small holes. ,
The aluminum and paper are separated by beating with a blade rotating at high speed inside the cylindrical screen, and the granular aluminum pieces and paper powder discharged from the small holes are sieved.

Function As mentioned above, the method of the present invention is to disintegrate aluminum foil paper shredded into small pieces by pure dry mechanical means without using water or chemicals. The foil paper is separated into aluminum and paper, and the aluminum is struck against the inner wall of the cylindrical screen by centrifugal force to form granules, and these granular aluminum pieces are discharged from the small holes of the cylindrical screen together with the paper powder. The paper powder discharged together with the granular aluminum pieces generates static electricity during sieving, becomes flocculent, remains on the sieve, and is separated from the aluminum pieces.

Example Hereinafter, specific examples of the method of the present invention will be described in detail.

First, aluminum foil paper for packaging (foil thickness 20P?7g)
Cutting waste and used waste are shredded into small pieces with several widths. Although any method of shredding may be used, a general office saw sawer was used in this example.

This large number of small pieces is then charged into a vertical cylindrical screen of a crusher and granulator. As this crushing and granulating machine, ■Furano Sea Mill (trade name) manufactured by Fuji Denki Omotesakusho was used. The cylindrical screen is a cylinder made of stainless steel plate with many small holes of 3 different inner diameters, and the inside has a 1.5KW
A blade-shaped rotary blade is provided that is driven by an electric motor and rotates at high speed.

The rotary blade is rotated at approximately 2000 rpm to strike small pieces of aluminum foil paper. Then, the aluminum and paper are separated, and the aluminum is struck against the inner wall of the cylindrical screen by centrifugal force and rotated, becoming spherical or irregularly shaped granules, which are discharged to the outside through the small holes of the cylindrical screen together with the paper powder.

When the amount of foil paper waste in the cylindrical screen decreases, new foil paper waste is replenished and the above operation is performed continuously.

The granular aluminum pieces discharged from the small holes of the cylindrical screen together with the paper powder are separated into a suitable mesh size (3 in this example).
Pass it through a rotating sieve (using a mesh mesh) to separate it from the paper powder.

At this time, the paper powder generates static electricity, aggregates, and becomes flocculent, so that it is easily separated from the aluminum pieces, remains on the sieve, and is discarded.

In this way, granular aluminum lamb pieces with a diameter of about 1 to 3 mm were obtained. The yield (weight ratio) of aluminum pieces to the raw material foil paper layer was 70% or more. This aluminum piece was highly pure dust with a metal purity of 98% or more, and it was possible to recover metal aluminum by using it as a raw material for remelting.

In addition, for beating the aluminum foil paper in the method of the present invention, it is possible to use not only the above-mentioned Furano Sea Mill but also various machines having the same type of function, and for sieving, not only a rotary sieve but also a vibrating sieve and an inclined sieve can be used. Other types of sieves may also be used.

Effects of the Invention As is clear from the above explanation, according to the method of the present invention,
Aluminum pieces that can be used for remelting can be recovered from aluminum foil paper waste at a high yield without using water or chemicals, without incineration, and with a small amount of power. Therefore, aluminum can be recovered at low cost without causing pollution, which greatly contributes to the utilization of resources.

Claims (1)

[Claims] Aluminum foil paper, which is made by bonding aluminum foil and paper, is shredded into small pieces, then placed in a cylindrical screen with many small holes, and struck with a blade rotating at high speed inside the cylindrical screen to form aluminum. A method for recovering aluminum, which comprises separating aluminum from paper and sieving the granular aluminum pieces and paper powder discharged from the small holes.