Heavies

Copper-zinc materials do not have a fixed classification system, and their classification is primarily based on the varying elemental composition of each product.

Copper-zinc materials are typically sourced from waste processing plants equipped with simple mechanical separation equipment (such as gravity separation or flotation) but lack manual sorting capabilities. These plants are prevalent in developed regions like Europe, Australia, and North America, where high labor costs make manual sorting unfeasible. As a result, they export mixed copper-zinc materials to countries with lower labor costs for further processing.
Copper-zinc materials primarily originate from high-copper, small-sized Zorba materials, which are often sourced from automobile shredding facilities. Other sources include household and industrial waste shredding facilities.

The value of copper-zinc materials lies in their copper-based metals (red metals), including brass, yellow copper, and insulated copper wires. Circuit boards are also a valuable component. Additionally, copper-zinc materials sometimes contain keys, coins, or other precious metals, often made of yellow copper, nickel, or silver, which hold significant value. The actual sorting and sampling of copper-zinc materials should not deviate significantly from the agreed-upon values, typically within 1-2%.

Traditional processing methods for copper-zinc materials involve machine-based sorting followed by manual sorting. Machine-based sorting includes techniques like cyclone separation, vibrating screen separation, and water washing. Manual sorting involves hand-picking and separating the various materials within the copper-zinc material. The resulting products are sorted into categories like broken brass, broken yellow copper, wire materials, broken circuit boards, broken zinc, and broken aluminum.
In recent years, a new processing method has emerged, which utilizes substitution and reduction reactions to extract valuable metals from copper-zinc materials. The first step involves separating the zinc/aluminum components, which account for the largest proportion of the material. The second step involves melting the remaining materials into alloy ingots. The third step uses solution and reduction reactions to extract high-value metals like gold, silver, palladium, and copper from the alloy ingots.
This new processing method has the advantage of eliminating the need for manual sorting, reducing personnel costs. However, it requires significant investment in equipment and construction, ranging from 50 million to 100 million yuan. Additionally, this method has potential environmental pollution risks, necessitating investments in wastewater treatment and management.

The detection methods for copper-zinc materials (Heavies) primarily involve sampling and testing. The first step is to collect a representative sample, typically ranging from 300 kg to 500 kg. When collecting samples, it is essential to:
1. Take samples from multiple containers.
2. Take samples from the top, middle, and bottom of the material pile.
After collecting samples, there are two detection methods:
1. Manual sorting and weighing of each component.
2. Melting the sample into a uniform metal block and conducting spectroscopic analysis.

Copper-zinc materials are typically sent to factories with low labor costs, where they can be manually sorted on a large scale. Due to the potential environmental pollution risks associated with processing copper-zinc materials, some countries, including China, have banned their importation. As a result, the most common destinations for copper-zinc materials are sorting factories in Thailand and Malaysia. Some high-quality copper-zinc materials can be sent back to China for further processing after polishing and cleaning.

When trading copper-zinc materials, it is essential to pay attention to the agreed-upon values for copper-based metals (red metals). The quoted data for copper-zinc materials often comes from historical data of similar products or downstream data, rather than actual testing. Even when suppliers conduct their own sorting and testing, their lack of expertise in manual sorting can lead to inaccurate data. Therefore, when evaluating copper-zinc materials, it is crucial to request as many actual product images as possible for analysis and identification. If the actual product does not match the quoted images, the supplier should be held responsible.
During the transaction process, it is essential to agree on the metal content and the acceptable deviation range. Typically, a deviation of 3% for metal content and 1-2% for copper-based metals is acceptable. If the deviation exceeds this range, there is a reasonable basis for filing a claim.