JP5404019B2 - Recycling method for waste aluminum products - Google Patents

Description

  The present invention relates to a recycling method for waste aluminum products, and is particularly suitable for reuse as a secondary material for steel making (for example, a deoxidizing material) or as a main raw material for an aluminum secondary alloy for used aluminum cans. It relates to the recycling method used.

  Conventionally, various techniques for collecting and recycling used beverage cans have been proposed. For example, as a treatment method for reusing used aluminum cans as a raw material for dissolving aluminum can plates, the aluminum cans are cut with a crusher, and the cut aluminum pieces are placed in a rotary kiln and fired at 550 ° C to 600 ° C. After burning and removing the surface coating, etc., it is put into an impact mill and repeatedly hitting and colliding with a striking plate or repulsion plate rotating at high speed, and forming into aluminum pellets (aluminum small spherical lump), It has been proposed that aluminum pellets remain as they are when the size is large, and are collected into a briquette machine and formed into a larger aluminum lump for reuse (see, for example, Patent Document 1).

  In addition, as a treatment method for separating and reusing steel pellets and aluminum pellets from a mixture of used steel cans and aluminum cans, the mixed beverage cans can be cut into pieces with a cutting machine. It is also proposed to put in a rotary kiln, heat to 450 ° C to 500 ° C, separate into steel pieces and aluminum pieces with a magnetic separator after heating, and form the separated aluminum pieces into aluminum pellets with a granulator (For example, refer to Patent Document 2).

  Furthermore, as a processing method for taking out the aluminum material of the lid part and the steel material of the trunk part separately from the used steel can and reusing them, the steel can is crushed with an impact crusher, and then the crushed pieces are removed. Heating with a rotary kiln to burn and remove surface coating, etc., and processing each piece of steel material and aluminum material after heating into steel pellets and aluminum pellets by a two-stage system of coarse granulator and granulator There has been proposed a method of separating into steel pellets and aluminum pellets using a magnetic separator after molding (see, for example, Patent Document 3).

JP-A-8-49023 JP-A-9-192640 JP-A-10-57931

  However, in the conventional recycling methods for waste aluminum products, all of them are granulated into a granular form called aluminum pellets for reuse. There is an inconvenience. Note that “granulation” in this case is different from the usual “granulation” technology in which powder is granulated and solidified to form pellets. It relates to a technique of forming into a granular form by force.

  That is, as the above inconvenience, the granulator used for pelletization is heavily worn, leading to an increase in running cost for maintaining the function, and a great amount of power energy is forced to drive, There is a point. In other words, the continuous operation of the granulator causes the holes in the screen to wear out and gradually collapse, resulting in non-uniform pellet size, an increase in the size of crushed powder, and maintenance and parts replacement frequency. This will cause an increase and a decrease in yield. For this reason, it has become an obstacle to establishing a business of reusing used aluminum cans as resources.

  In addition, the specific gravity of aluminum pellets is so low that it is difficult to reuse as an auxiliary material for steelmaking. That is, there are things that fall from the conveyor when thrown into the final melting furnace and cause the yield of the final melting amount to deteriorate, or those that blow up when reaching the final melting furnace and do not reach the lower part of the furnace There is.

  When recycling used aluminum cans, even if the used aluminum cans are cut before heating, it is possible to sort out non-steel foreign matter, regardless of the sorting and removal of steel foreign matter. -Removal tends to be difficult, and may be formed into aluminum pellets with foreign matter mixed in, resulting in a significant decrease in the purity of aluminum.

  The present invention has been made in view of such circumstances, and its purpose is to recycle waste aluminum products that can omit a granulation step and obtain a recyclable raw material with high specific gravity and high purity. It is to provide a processing method.

  In order to achieve the above object, the present invention targets a recycling method for waste aluminum products, and is a temperature condition capable of preventing oxidation in a heating furnace in which the waste aluminum product is in a reducing atmosphere. A heat treatment process for dry distillation in a predetermined temperature range, a crushing process for crushing and cutting into aluminum pieces after the heat treatment process, and a briquette molding for compressing and solidifying the aluminum pieces after the crushing treatment process to form aluminum briquettes A process. Here, as said predetermined temperature range, 400 degreeC-500 degreeC, Especially 400 degreeC-450 degreeC are mentioned as a preferable thing.

  In the case of this specific matter, the heat treatment process makes it possible to thermally decompose the surface-treated paints and coating materials, or moisture and impurities adhering to the surface without oxidizing the waste aluminum product. Impurities other than the aluminum alloy, which is the original material, can be removed from the aluminum product and annealed. Next, in the crushing process, the annealed waste aluminum product after heat treatment is crushed and cut into aluminum strips, and the aluminum strips are compressed and solidified in the briquette forming process to produce high specific gravity and high purity aluminum. Briquette will be obtained. This aluminum briquette is reused as a secondary material for steel making such as a deoxidizing material or a raw material for a new aluminum product. In addition, in particular, in the heat treatment process, a heat-sealable heating furnace, a circulation fan, and a heating gas generation chamber are used. Circulation supply to the generation chamber is performed, and combustion exhaust gas generated by burning pyrolysis gas in the heating gas generation chamber is supplied to the heating furnace as a heating source for dry distillation in a reducing atmosphere (claim 1). In this case, the pyrolysis gas generated by dry distillation in the heating furnace is combusted in the heating gas generation chamber, and the combustion exhaust gas is returned to the heating furnace, so that the heat treatment in the reducing atmosphere in the heat treatment process is reliably performed. It will be.

  In this invention, when a large number of waste aluminum products are used as press raw materials in a state of light compression molding into a rectangular shape, the press scrap is released from the light compression molding state and separated into individual waste aluminum products. A foreign matter removing step for removing foreign matter adhering to or mixed in the waste aluminum product from the waste aluminum product in an individually separated state as a pre-step of the heat treatment step. (Claim 2). In this case, it is possible to specify a recycling method in accordance with the actual situation such as collection of waste aluminum products and handling after collection. Since the waste aluminum product separated in the release process is subjected to the foreign matter removal process in that state, it is easier to remove the foreign matter than the conventional method of removing the foreign matter after first crushing and cutting the waste aluminum product. It can be performed reliably, and can contribute to the high purity of the aluminum briquette that will be the final recycled product.

  In addition, the cutting step of cutting the aluminum briquette formed by the briquetting molding step into a size corresponding to the purpose of reuse as a recycled product can be executed as a subsequent step of the briquetting molding step. . In this case, it is possible to adjust the size and weight to the optimum according to the application for which the recycled product is reused, and the handling property and the certainty of reuse are improved.

More specifically, for used aluminum cans as waste aluminum products, the heat treatment process is dry-distilled in the temperature range of 400 ° C to 500 ° C, and crushing and cutting into aluminum strips with a width of 15 mm or less in the crushing process. In the briquette molding step, it can be compressed and solidified into an aluminum briquette having a specific gravity of 2.2 g / cm ³ or more. In this case, it can be embodied as a recycling method for producing a recycled product using a used aluminum can as a starting material. That is, it is removed by thermal decomposition of the surface paint, etc. in a state in which oxidation is reliably prevented by heating in the above temperature range, and the aluminum strip is cut into an aluminum strip having a width of 15 mm or less to make the aluminum strip a material. Thus, the compressed and solidified aluminum briquette can be reliably molded to a high specific gravity of 2.2 g / cm ³ or more.

  As described above, according to the method for recycling aluminum cans according to any one of claims 1 to 4, a paint or coating material that has been surface-treated without oxidizing waste aluminum products by a heat treatment step, Alternatively, moisture and impurities adhering to the surface can be thermally decomposed, so that impurities other than the aluminum alloy that is the original material can be surely removed from the discarded aluminum product and annealed. become. Next, the aluminum pieces produced by crushing and cutting the waste aluminum product after heat treatment in the crushing process can be compressed and solidified in the briquette forming process to obtain aluminum briquettes with high specific gravity and high purity. By using briquette, it becomes possible to obtain a recycled product that is reused as a secondary material for steelmaking such as a deoxidizing material or a raw material for a new aluminum product. In particular, in the heat treatment process, a heatable furnace that can be sealed, a circulation fan, and a heated gas generation chamber are used to heat the combustion exhaust gas by burning pyrolysis gas generated by dry distillation in the heating furnace in the heated gas generation chamber. Since it is made to return to a furnace, the heat processing in the reducing atmosphere in a heat processing process can be performed reliably.

  According to the second aspect, by adding the release step and the foreign matter removal step as the pre-process, it is possible to specify a recycling method that meets the actual situation such as collection of waste aluminum products and handling after the collection. In particular, since the foreign matter removal process is performed in the state of the waste aluminum product separated by the release process, foreign matter removal is easier and more reliable than the conventional method of removing foreign matter after first crushing and cutting the waste aluminum product. As a result, the aluminum briquette that will be the final recycled product can be highly purified.

  In addition, according to claim 3, by adding a cutting step as a post-process, it is possible to adjust the size and weight to the optimum size according to the application for which the recycled product is reused. Certainty can be improved.

Furthermore, according to the fourth aspect, the present invention can be embodied as a recycling method for manufacturing a recycled product using a used aluminum can as a starting material. That is, it is possible to remove the surface paint and the like in a state in which oxidation is reliably prevented by heating in a temperature range of 400 ° C. to 500 ° C. An aluminum briquette made by compressing and solidifying a piece as a material can be reliably molded to a high specific gravity of 2.2 g / cm ³ or more.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a process diagram of a recycling method for waste aluminum products according to an embodiment of the present invention. The present invention includes a heat treatment process P3 using a dry distillation reduction-type heating furnace that can be carbonized in a reducing atmosphere, a crushing process process P4 that is shredded and cut into pieces of aluminum using a shredder after the heat treatment, and a crushing process. It is characterized in that it is combined with a briquette molding step P5 in which a later aluminum strip is used as a material and molded into an aluminum briquette by a briquette machine. That is, in the heat treatment step P3, the paint or coating material that has been surface-treated without oxidizing the waste aluminum product, or moisture and impurities attached to the surface are thermally decomposed. By this heat treatment process P3, impurities (including the above-mentioned paint and the like) other than the original aluminum alloy are removed and annealed from the discarded aluminum product. Next, in the crushing step P4, the annealed waste aluminum product after heat treatment is crushed and cut with a shredder to form aluminum strips (for example, about 15 mm or less in width), and the aluminum strips in the briquette forming step P5. A predetermined high specific gravity and high purity aluminum briquette is obtained by molding and solidifying into a predetermined size with a predetermined compression force by a briquette machine.

  Next, a specific example for a used aluminum can as a waste aluminum product will be described. Here, the aluminum can is a beverage can made of an aluminum alloy (hereinafter simply referred to as “aluminum”). Generally, the body portion is made of an A3000 series aluminum alloy and the lid portion is made of an A5000 series. It is formed of an aluminum alloy.

  Generally, used aluminum cans are collected separately by a waste collection company or collected in a mixed state with steel cans and then sorted into steel cans. In order to supply, it is made into a rectangular lump called so-called aluminum can scrap. The aluminum can scrap 10 is lightly pressed together by a predetermined amount and compressed and molded into a state where individual aluminum cans are lightly crushed, and is formed mainly for convenience of transportation and handling. Recycling companies that have supplied such aluminum can scrap 10 are recycled as steelmaking auxiliary materials (for example, deoxidizing materials) after the processing steps P1 to P6 described below are performed. Products 14, 14,...

  As a processing method for manufacturing a recycled product 14 as a secondary material for steel making, a necessary treatment due to the fact that the starting raw material is the aluminum can scrap 10 and the removal of foreign substances that can be sorted relatively easily are performed. Necessary to adjust the specifications such as size, weight, etc. according to the use destination of recycled products It is divided into post-processing steps. The pretreatment process includes a release process P1 and a foreign matter removal process P2, and the present process process includes a heat treatment process P3, a crushing process process P4, and a briquette molding process P5, and the post-treatment process is a cutting process. P6 is provided.

  Hereinafter, each process will be described in detail with reference to FIG. 2 in addition to FIG. In the release process P1, an impact force or a vibration force is applied to the aluminum can scrap 10 to separate and release the aluminum can scrap 10 into individual aluminum cans 11, 11,. The aluminum cans 11, 11,... Are peeled one by one from the scraps 10 of the aluminum cans without being crushed using a so-called release machine. In this release process P1, the aluminum can scrap 10 is transported from the stock yard by, for example, an excavator loader, and placed on the input conveyor 21 at a predetermined timing, and is input to the impact type uniaxial crusher 22 as the release machine by the input conveyor 21. To do. The impact type uniaxial crusher 22 is rotated in the impact type uniaxial crusher 22 to release the bond and peel it off. Further, the vibration feeder 23 absorbs the released impact and disperses them one by one. The aluminum cans 11, 11,..., Which are dispersed separately, are sent to the next foreign matter removing step P2. As the vibration feeder 23, for example, a lower vibrator coil spring support type may be used.

  For example, an apron conveyor 24 having a tail equipped with a hopper 24a may be used for conveyance from the release process P1 to the foreign substance removal process P2. That is, the aluminum cans 11, 11,... Separated from the vibration feeder 23 are put into the hopper 24 a and stored in the hopper 24 a. A fixed amount is conveyed to the conveyor 25. Here, the apron conveyor is a chain conveyor that can be conveyed in large quantities with a steep inclination (for example, an inclination angle of 45 degrees). A plate called an apron is attached to the conveyor chain, and the object is conveyed by advancing the conveyor chain. Is conveyed to an upper position.

  The foreign matter removing process P2 performs sorting / removal of foreign matter / dangerous materials by manual sorting, and sorting / removal of steel foreign matter by magnetic sorting (magnetic sorting). The hand sorting is performed based on the operator's visual recognition while flowing the aluminum cans 11, 11,... Supplied by the apron conveyor 24 to the hand sorting conveyor 25, and the magnetic separation is performed by a magnetic separator (for example, a permanent magnet suspension belt type magnetic separation). Machine) 26 to select and automatically discharge steel foreign objects (eg, nails, screws, etc.). The objects of hand sorting are foreign substances (for example, food cans other than empty beverage cans, confectionery cans, etc.) and dangerous substances (spray cans, etc.) mixed in aluminum cans 11, 11,. And dangerous materials are collected in the container C1 and disposed of.

  The aluminum cans 11, 11,... That have undergone the foreign matter removal step P2 are, for example, by a quantitative supply means comprising a pool conveyor 27 with a storage tank having a temporary storage function and a quantitative dispensing function, and an apron conveyor 28 capable of quantitative and continuous supply. In order to realize uniform heating in the heating furnace 29 to the heating furnace 29 of the heat treatment P3 in the next step, a constant amount is supplied at a predetermined flow rate and is continuously supplied.

  In the heat treatment P3, the surface paint or coating of the aluminum can 11 is thermally decomposed by exposing the aluminum can 11, 11,... To a high temperature inert gas at a predetermined temperature that is fired under reducing conditions in a non-oxygen atmosphere. Thus, while preventing oxidation of the aluminum can 11, impurities other than the original aluminum alloy are removed from the aluminum can 11, and at the same time, the aluminum can 11 is fired.

  As an equipment for realizing such heat treatment P3, in the present embodiment, the aluminum cans 11, 11,... Are dry-distilled under reducing conditions while being maintained in a non-oxygen atmosphere in which oxygen is almost absent or oxygen is not present. A reductive carbonization type heating furnace (rotary kiln) 29 configured to be able to be used is used. This heating furnace 29 is provided with a hopper 29a for storing aluminum cans 11, 11,... Supplied by an apron conveyor 28 on the inlet side and a double damper 29b, while a double damper is also provided on the outlet side. 29c is provided, and the aluminum cans 11, 11,... To be heated can be supplied (introduced) while the inside is kept sealed by alternately opening and closing the respective double dampers 29b, 29c. The heating furnace 29 is provided with a cyclone dust collector 30, a circulation fan 31, and a heating gas generation chamber 32 constituted by a complete combustion furnace, and pyrolytic gas (combustible gas) generated by dry distillation in the heating furnace 29. .. Are exhausted completely, and the combustion exhaust gas is recirculated to the heating furnace 29 to heat the aluminum cans 11, 11.

  Then, by the operation of the circulation fan 31, the pyrolysis gas containing aluminum dust generated in the heating furnace 29 is led out from the heating furnace 29 and sent to the cyclone dust collector 30, and the aluminum dust is separated and recovered from the pyrolysis gas in the cyclone dust collector 30. The remaining pyrolysis gas from which the aluminum dust has been removed is sent to the heated gas generation chamber 32. The heated gas generation chamber 32 is supplied with fuel gas (for example, LP gas) from an external fuel supply source (for example, LP gas cylinder) 33 and completely burns the fuel gas and the pyrolysis gas. The high-temperature combustion gas (combustion exhaust gas) is adjusted to a temperature that serves as a firing condition and to a predetermined temperature that can prevent oxidation of the aluminum can 11, and then circulated in the heating furnace 29. As a result, it is possible to reliably prevent the aluminum can 11 from being oxidized in the heating furnace 29 and to thermally decompose impurities such as the surface paint and coating of the aluminum can 11 under a firing temperature condition lower than the melting point of the aluminum alloy. The temperature conditions should be adjusted. As such temperature conditions, the aluminum cans 11, 11,... Can be heated in a temperature range of 400 ° C. to 500 ° C., preferably in a temperature range of 400 ° C. to 450 ° C. It is preferable that the heating temperature with respect to ... is substantially 410 ° C. The aluminum dust separated and collected by the cyclone dust collector 30 can be a kind of recycled product as a fired powder of aluminum. The surplus gas in the heated gas generation chamber 32 is released to the atmosphere through a bag filter after the cooling process.

  Next, the aluminum can that has been baked by the heat treatment (hereinafter referred to as “aluminum baked can”) is crushed and cut into the aluminum strips 12 in the subsequent crushing process P4. At this time, the aluminum calcined can taken out from the heating furnace 29 through the damper 29c on the outlet side is led out to the outlet conveyor 34 constituted by, for example, a steeply inclined apron conveyor, and after being cooled by air while being conveyed by the outlet conveyor 34 Then, it is put into the shredder 36 through a switching damper chute 35 that can be discharged. As a result, when an abnormal situation occurs, for example, when a predetermined amount or more of aluminum calcined cans flow out to the transfer line, the switching damper chute 35 is switched to the abnormal discharge side, and the incremented aluminum calcined cans are transferred to the container C2. So that the continuous operation of the subsequent steps P4, P5 and P6 can be maintained. The aluminum baking cans stored in the container C2 can be returned to the inlet side of the outlet conveyor 34 again.

As the shredder 36 used in the crushing process step P4, for example, a uniaxial crusher may be used. A single-shaft grinder crushes and cuts an aluminum calcined can introduced from a hopper between a cemented carbide rotary blade and a fixed blade. It is discharged as a piece 12, and the larger one is scraped up and the above crushing and cutting are repeated. The aluminum strip 12 produced by the crushing process P4 has a crushing width (cutting width) of about 15 mm or less for increasing the specific gravity, which is the required quality of the briquette 13 in the next briquetting molding process P5. preferable. In particular, it is preferable that the crushing width is substantially 10 mm or less and the bulk specific gravity is about 0.7 t / m ³ . Further, in terms of crushing efficiency, a rotary blade arranged in a V shape is preferable.

In the briquette molding process P5, the aluminum strips 12, 12,... Are compressed and solidified to mold the briquette 13 having a shape and high specific gravity required as a recycled product. The shape may be formed into a columnar shape having a circular or elliptical cross section, or a prismatic shape having a cross section such as a triangle or a quadrangle, and the size is about 100 mm at maximum when the shape is a cylindrical shape. The diameter may be preferably about 60 to 80 mm, and the degree of compression may be a specific gravity of substantially 2.2 g / cm ³ or more, for example. In order to mold such a briquette 13, a predetermined amount of aluminum strips 12, 12,... . As described above, the briquette 13 having a high purity and a uniform specific gravity up to the inside and a required high specific gravity (about 2.2 g / cm ³ or more) can be molded.

  The briquette molding process P5 is performed using a briquette molding machine 39, and the cutting process P6 is performed by attaching a cutting machine 40 to the briquette molding machine 39. On the other hand, in order to supply the aluminum strips 12, 12,..., The aluminum strips 12, 12,... Discharged from the shredder 36 are dropped onto the belt conveyor 37, and then to the briquette molding machine 39 by the belt conveyor 38. It can be supplied separately. Moreover, the cutting waste generated in the cutting process P6 described later is returned to the briquette molding process P5 and is compressed and solidified together with the aluminum strips 12, thereby improving the yield and contributing to the higher specific gravity.

  In the cutting process P6, when the briquette 13 is too large or too heavy as a recycled product with the size and weight as it is, the briquette 13 is cut to the weight and size according to the use of the recycled product. Recycled products. As the cutting machines 40a and 40b for executing the cutting process P6, for example, an aluminum circular saw cutting machine including a carbide circular saw may be used in consideration of cutting efficiency. For use as a secondary material for steel making (deoxidation material), if the briquette 13 is, for example, about 80 mm in diameter, a flat cylindrical cutting piece that weighs about 200 g when cut to a length of about 18 mm. 14, 14,... Recycling by forming such a flat cut piece 14, that is, a flat cut piece 14 whose both end faces are flat and the height (length) between both end faces is extremely short compared to the diameter. It becomes possible to sufficiently ensure the handleability at the time of use of the product, particularly the stability at the time of conveying the conveyor, and it is possible to surely avoid the occurrence of inconvenience such as falling down.

  In the case of the recycling method according to the present embodiment as described above, a secondary material for steelmaking (deoxidation) is obtained by using a used aluminum can as a raw material, omitting the granulation step in the conventional method and pelletizing (granulating). The recycled product 14 having a high specific gravity (eg, 2.2 g / cm 3) and high purity (eg, an aluminum alloy component of 96% by weight or more) that can be reused as a material can be manufactured. For this reason, it is possible to omit the installation of the granulator, which was necessary in the conventional method, and accordingly, the increase in the maintenance frequency and the deterioration of the yield due to the wear of the granulator are prevented, and the cost required for them. Both reduction of power consumption and reduction of power energy for driving can be realized. In addition, the cut piece 14 as a recycled product has a shape that is stable even when placed on the conveyor, so that it can be stably supplied to the final melting furnace and has the required weight, so that the final melting is possible. If it is put into the furnace, it can reach the lower part of the furnace without fail, and can contribute to the improvement of steelmaking quality. Furthermore, unlike the conventional method of cutting and cutting into pieces before the heat treatment, the foreign matter removing step P2 is performed in a state where the aluminum can scraps 10 are separated into individual aluminum cans 11 before the heat treatment. Since the crushing process P4 is performed after the process P3, it is possible to more easily and reliably remove foreign substances other than steel foreign substances that can be magnetically selected. Thereby, compared with the conventional method in which the case where it is easily formed into aluminum pellets with foreign matter mixed in is easily generated in this embodiment, the final recycled product can be highly purified.

  In particular, the foreign matter is removed by manual selection or magnetic separation without crushing the aluminum can in the stage before heating, and the surface coating or the like is subjected to thermal decomposition (dry distillation) in a reducing atmosphere in the heat treatment step P3. Due to the removal, it is possible to further increase the purity of the final recycled products 13 and 14. Furthermore, since the briquette molding process P5 is performed by using the aluminum strip 13 that has been annealed by the heat treatment process P3 and then chopped by the crushing process process P4, the final recycled products 13 and 14 Higher specific gravity can also be achieved.

  It should be noted that dust containing aluminum dust passes through a dust collection duct (not shown) from various places in the cover 34a of the outlet conveyor 34, the shredder 36, the briquette molding machine 39, and the cutting machine 40 to a cyclone dust collector (not shown). In this cyclone dust collector, aluminum dust is collected, and fine powder mainly containing carbon remaining after the aluminum dust is removed is collected by a bug filter (not shown). These aluminum dust and carbon fine powder can be reused separately.

<Other embodiments>
In addition, this invention is not limited to the said embodiment, Various other embodiments are included. That is, in the embodiment described above, aluminum cans, which are mainly used beverage containers, have been described as raw materials for recycled products. However, the present invention is not limited thereto, and other aluminum containers and aluminum alloys such as aluminum sashes are used as materials. You may make it apply the recycling processing method of this embodiment by making the aluminum product manufactured and discarded after that into the raw material of a recycled product. In these cases, as with aluminum can scrap, waste aluminum products are lightly pressed at a waste collector and supplied to a recycling processor in the form of aluminum scrap, and the recycling processor starts recycling processing from this form. Therefore, the above embodiment can be applied.

  In the above embodiment, the case where aluminum cans are targeted and the scraps of these aluminum cans are used as starting materials has been described. However, it is of course possible to start the foreign matter removing step P2 for the collected aluminum cans without using the form of aluminum can scrap.

It is a block process diagram showing an embodiment of the present invention. It is a schematic diagram which shows the manufacturing line of a recycled product.

Explanation of symbols

P1 Release process P2 Foreign matter removal process P3 Heat treatment process P4 Crushing process P5 Briquette molding process P6 Cutting process 29 Heating furnace 31 Circulating fan 32 Heating gas generation chamber

Claims (4)

A heat treatment step in which the waste aluminum product is subjected to dry distillation in a predetermined temperature range which is a firing temperature condition and a temperature condition capable of preventing oxidation in a heating furnace in a reducing atmosphere;
Crushing process after crushing and cutting after heat treatment process into aluminum pieces,
A briquette molding process that compresses and solidifies the aluminum pieces after the crushing process and molds them into aluminum briquettes;
In the heat treatment step, a heatable furnace, a circulation fan, and a heating gas generation chamber are used, and the pyrolysis gas generated by heating in the heating furnace is circulated to the heating gas generation chamber by the operation of the circulation fan. The waste aluminum product is characterized in that it is supplied as a heat source for dry distillation of the combustion exhaust gas generated by burning pyrolysis gas in the heating gas generation chamber in a reducing atmosphere to the heating furnace. Recycling method. A method for recycling waste aluminum according to claim 1,
A release process in which a large number of waste aluminum products are lightly compression-molded into a rectangular shape as a starting material, and the press scrap is released from the light compression-molded state and separated into individual waste aluminum products. A waste aluminum product recycling process in which a foreign matter removing step for removing foreign matter adhering to or mixed in the waste aluminum product from the separated waste aluminum product is executed as a pre-process of the heat treatment step. Method. A method for recycling aluminum waste products according to claim 1 or claim 2,
A recycling method for waste aluminum products, wherein a cutting process for cutting aluminum briquettes formed by the briquetting molding process into a size corresponding to the purpose of reuse as a recycled product is performed as a subsequent process of the briquetting molding process. A recycling method for waste aluminum products according to any one of claims 1 to 3,
Targeting used aluminum cans as waste aluminum products, the heat treatment process is dry-distilled in the temperature range of 400 ° C to 500 ° C, crushing and cutting into aluminum strips with a width of 15 mm or less in the crushing process, and 2 in the briquette molding process A method for recycling waste aluminum products that is compressed and solidified into aluminum briquettes having a specific gravity of 2 g / cm ³ or more.

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