Introduction
Aluminum scrap is one of the most valuable recyclable materials due to its high value and abundance in the waste stream. In order to maximize the value of aluminum scrap, its recovery and recycling must not only be simple and cost-effective, but also be sustainable and create a circular production process. In order to effectively promote aluminum scrap recycling, attention should be paid to the pre-treatment of aluminum scrap. It should first be cut into slices, and the efficiency and cost of slicing should be improved so as to achieve an ideal aluminum resource recycling system.
Section I
As a very difficult material to process in situ, aluminum scrap is often pre-processed before processing and recycled. In traditional pre-treatment methods, scrap aluminum pieces are firstly cut into small slices with thickness of 0.04-6mm and then further processed to obtain secondary aluminum products. To do this, pre-treatment technology is essential. However, Aluminum cuttings requires a high level of cuttings technology in order to maximize efficiency and ensure product quality. The common pre-treatment methods for aluminum scrap include guillotine cutting, one-time drawing, semi-continuous tension drawing, continuous tension drawing, etc.
Guillotine cutting is the most widely used pre-treatment method for aluminum scrap since it is simple and cost-effective. It is used to cut an aluminum sheet with a thickness of 0.04-6mm into a suitable length and width. The cut pieces can then be further processed. It is a one-time processing method that produces scrap pieces with varying lengths and widths.
The one-time drawing technique is similar to guillotine cutting, but a larger number of pieces are produced in this method. They are usually of a smaller size, with a thickness of 0.03-0.3mm, and a length of 20-60 mm. The pieces are then sorted and further processed.
The semi-continuous tension drawing method relies on the tension of the aluminum strip being drawn through a multi-stage rolling system. The resulting pieces have an accurate size and thickness, generally within 0.2-2mm.
The continuous tension drawing method is similar to the semi-continuous tension drawing method, but the sheet is pulled through a continuous system with different rollers and roller speed. This method yields pieces with accurate size, thickness and length, and theoretically, no material loss.
Section II
The current status of aluminum scrap pre-treatment in China can be divided into three stages according to the types of slicing equipment and technical processes.
The first stage is large manual cutting equipment. In this stage, there are mostly active shears, medium-sized and small shears, which are usually driven by manual labor and electricity. These techniques are characterized by low control accuracy, large cutting errors, manual control, and low precision. The process is more suitable for the large and thick aluminum sheet.
The second stage is mechanical guillotine cutting equipment. Mechanical guillotine cutting is the most widely used pre-treatment method for aluminum scrap due to its simple and cost-effective features. The process is characterized by good controlling accuracy, low cutting errors, fast cutting speed and high output.
The third stage is automatic cutting equipment. In this stage, mostly automatic cutting equipment is used, such as laser cutting and plasma cutting. These methods are characterized by higher control accuracy and cutting precision, faster cutting speed and better material utilization.
Conclusion
Aluminum recycling has become increasingly important in recent years due to its high value and abundance in the waste stream. In order to maximize the value of aluminum scrap, pre-treatment methods such as guillotine cutting, one-time drawing, semi-continuous tension drawing and continuous tension drawing should be employed. These methods vary in their level of accuracy, cutting errors, speed, and material utilization. Current aluminum pre-treatment methods in China can be divided into three stages according to the types of slicing equipment and processes, namely large manual cutting equipment, mechanical guillotine cutting equipment, and automatic cutting equipment. In order to promote aluminum scrap recycling, attention should be paid to pre-treatment of aluminum scrap, and further improve the efficiency and cost of slicing should be made so as to achieve an ideal aluminum resource recycling system.
