Why Can Aluminum Be Recycled?
Aluminum metal has strong corrosion resistance. Except for some aluminum chemical containers and devices, aluminum is almost not corroded during use, and the loss is very small. It can be recycled and recycled many times. Therefore, aluminum is highly recyclable. . After steel, aluminum is currently the most used metal in the world. Among non-ferrous metals, aluminum ranks first in terms of reserves, output and consumption. In 1997, the production and consumption of aluminum in the world reached 22 million tons and 23 million tons respectively. Aluminum is used in a wide range of applications. Civil, military, construction, transportation, transportation, electronic telecommunications, household appliances, electric power, machinery… Aluminum alloys are almost ubiquitous in all walks of life. The ratio of primary aluminum to secondary aluminum in developed countries is close to or exceeds 1:1.
Because of this, the recycling of waste aluminum has become a work that countries all over the world attach great importance to, and has become an important industry. With the increase of output and usage, the amount of waste aluminum products is also increasing. Moreover, many aluminum products are disposable, and the time from the finished product to the loss of use value of the product is relatively short. Therefore, these waste miscellaneous materials have become a source of pollution. The question of how to use recycling is very urgent, so how many times can aluminum be recycled?
This article will introduce you to the benefits of recycling aluminum, the process of recycling aluminum, the best aluminum scrap, and the question of how much aluminum you can get back after it is recycled.
What Are Some Of The Benefits Of Recycling Aluminum?
- Cost saving
Waste aluminum recycling is generally recovered from factories, enterprises, and manufacturing industries. In factories, some unqualified and unusable waste aluminum products are piled up in warehouses and have been depreciated. Scrap equipment with use value, scrap aluminum shavings in metal smelting factories, and other scrap metal materials, etc. Even if these scrap aluminum and scrap aluminum products have lost their original value, if these scrap aluminum and equipment are recycled Reproduction and utilization will not only reduce the production cost of the enterprise, but also save resources.
- Save energy
Recycling aluminum uses about 5% of the energy required to smelt bauxite to regenerate it, thereby creating secondary aluminum; visually seeing the energy required to convert alumina into aluminum saves a lot of resources.
- Environmental protection and energy saving
Recycled aluminum would use 5% of the energy that would be needed to create the same amount from raw materials. The benefits relative to CO2 emissions depend on the type of energy used. Electrolysis can use electricity from non-fossil fuel sources such as nuclear, geothermal, hydro power generation, or solar energy to complete. Aluminum production is attracted to cheap sources of electricity. Efficient production and recycling are good for the environment.
- The recycling of recycled aluminum cannot be ignored
The white dross of primary aluminum production and secondary recycling operations still contains useful amounts of aluminum and can be extracted industrially. Aluminum billets are produced in this process, together with highly complex scrap. This waste is unmanageable. It reacts with water, releasing
Out gasses (including mixtures including hydrogen, acetylene, and ammonia) in which they spontaneously ignite on contact with air; contact with moist air will result in the formation of large quantities of ammonia gas released.
What Process Is Used To Recycle Aluminum?
1、Classification
Primary classification of aluminum scrap, grading and stacking, such as pure aluminum, deformed aluminum alloy, casting aluminum alloy, mixed materials, and so on. All incoming raw materials are stored in separate areas, and the inventory is managed and utilized according to the quantity, chemical composition, recovery rate and cost.
For scrap aluminum products, it is necessary to disassemble, remove the steel and other non-ferrous metal parts connected with aluminum, and then made into scrap aluminum through cleaning, crushing, magnetic separation, drying and other processes; for thin and loose pieces of scrap aluminum, it is necessary to use hydraulic metal baler to press into a packet; for steel-core aluminum stranded wire, it should be separated from the steel core first, and then wind the aluminum wire into a coil.
2、Pre-processing
The purpose of pretreatment of scrap aluminum has four purposes: one is to remove the scrap of aluminum mixed with other metals and impurities; two is the scrap of aluminum according to the composition of the classification, so that the alloy composition to get the maximum degree of use; three is the scrap of aluminum surface oil, oxides and coatings, etc. to deal with; four is to make the aluminum scrap containing the most economic and reasonable use of aluminum. The final result of pretreatment is to treat the aluminum scrap into a furnace material that meets the furnace conditions.
Pretreatment technology mainly includes:
A, sorting, that is, sorting out plastics, rubber and other non-aluminum materials.
B, washing, i.e. washing off the oil and other substances in the aluminum scrap.
C, paint removal, in order to reduce the pollution generated by incomplete combustion of the surface coating of scrap aluminum, should focus on the paint removal treatment of coated scrap aluminum before entering the furnace.
Pre-treatment at the same time, but also separated out a variety of non-aluminum substances, to get the pure aluminum scrap, which is also a necessary safeguard for melting high-quality aluminum alloy.
3、Processing
After pre-treatment, part of the recycled aluminum will be cold processed to turn it into powdered aluminum, and the other part will be recycled by heavy media beneficiation, parabolic beneficiation and other methods.
A、Remelting
Scrap aluminum should be dried before melting to remove moisture, lubricants, oil and so on. Generally available reverse drying furnace and box drying furnace. In the modern drying production line are equipped with exhaust gas combustion chamber, dust collector, the exhaust gas, waste water purification treatment.
Most of the recovered scrap aluminum is remelted back to the furnace, casting for recycled aluminum ingots, or a small portion of scrap aluminum for direct reforming and utilization. Pretreated aluminum scrap in the furnace melting, refining and adjusting the alloy composition, generally in the reflector furnace and electric furnace. There are double chambers (preheating chamber and melting chamber) in the furnace. Refining is an important part of melting, which includes melting aluminum or alloy liquid surface to add flux cover, so as to avoid the liquid aluminum by air oxidation, while passing into the liquid to impose the stirring effect, to promote which inclusions and hydrogen separation out.
- Heavy media classification
Aluminum alloys of different compositions have different densities and can be sorted by heavy media. Generally speaking, aluminum-magnesium alloy, aluminum-magnesium-silicon alloy than aluminum-zinc alloy, aluminum-copper alloy, aluminum-silicon alloy density is small, and heavy-media sorting can be in accordance with their density to carry out effective sorting. Heavy media sorting is considered to be one of the most effective gravity sorting methods, based on lower basic investment and operating costs, with higher cost processing methods to create the final product.
What Is The Best Aluminum To Scrap?
Aluminum scrap is a common name for recycled aluminum, and it is also the main raw material for recycled aluminum. Aluminum scrap can be divided into “new aluminum scrap” and “old aluminum scrap”. New aluminum scrap refers to the process waste produced by downstream aluminum processing enterprises and foundry enterprises in the production process, that is, products that are scrapped due to unqualified performance; Old scrap aluminum refers to scrap aluminum and scrap aluminum parts purchased from the society, that is, scrap aluminum produced in life, including old aluminum doors and windows, aluminum parts in scrapped cars and machinery, aluminum conductors and aluminum metal parts in scrapped power grids wait. Aluminum scrap generally refers to old scrap aluminum and new scrap aluminum that is sold to recycling or recycling aluminum companies.
There may not be the best scrap aluminum, it mainly depends on the current scrap aluminum market. It’s worth noting that some types of aluminum that are commonly sought after in scrap yards include:
Clean Aluminum Scrap: This includes items such as aluminum cans, clean aluminum foil, and clean aluminum sheet. These items are usually easy to collect and can be recycled efficiently.
Extrusion scrap: This includes items such as aluminum framing, door and window frames. These items contain a higher percentage of aluminum than other types of scrap, making them ideal for recycling.
Cast Aluminum Engine Blocks: These are often found in old car engine blocks and can produce large amounts of aluminum when scrapped.
Aluminum Wheels: Aluminum wheels for cars and trucks fetch a premium due to their relatively high aluminum content.
Can You Obtain 99.9% Aluminium Through Recycling?
99.9% pure aluminum is obtained through the recycling process. Aluminum recycling involves melting aluminum scrap or waste and refining it to remove impurities. Multiple recycling and refining steps can be applied to increase the purity of the aluminum. While achieving 100% purity is challenging, it is possible to obtain 99.9% pure aluminum through recycling technology.
