Recycling background

The global electronic information industry is rapidly expanding at a compound annual growth rate of 7%, directly driving the annual generation of electronic waste to exceed 50 million tons. Among them, waste chips have become a “resource rich collective” due to their high integration – a single ton of waste chips contains about 300 grams of gold (80-100 times the grade of natural gold mines), 20-30 kilograms of copper, and silicon matrix accounts for more than 60%, making it a “metal deposit at your fingertips”.

Chip recycling production line: multi process collaborative architecture

The entire production line follows the logic of “material dissociation → grading and sorting → pollution control”, integrating four core units: PNMP mill, airflow specific gravity separation, electrostatic separation, and pulse dust removal, to achieve efficient separation and clean production of “metal silicon”.

Vibration feeding: stable feeding

By using a vibrating feeder, the waste chips are evenly transported to the grinding machine. Control the feed rate to avoid overloading or idling of the grinding machine due to “feed fluctuations” and ensure the continuity of subsequent processes.

PNMP powder mill: achieving material dissociation

The chip is made up of metal circuits (copper, gold, etc.) tightly bonded to a silicon substrate. The grinding machine breaks the block shaped chip into 30-60 mesh fine powder through mechanical impact force and shear force, causing the metal particles to dissociate from the silicon substrate (particles exist independently). This step is the foundation for subsequent sorting – only when the material particles are separated can the differences in density and conductivity be utilized.

Airflow specific gravity separation: sorting of coarse metal particles

The specific gravity separation of airflow utilizes the density difference between metals (copper 8.96g/cm ³, gold 19.32g/cm ³) and silicon (2.33g/cm ³). In the rising airflow field, coarse metal particles are collected first due to rapid settling, and silicon powder enters the subsequent process with the airflow, with a preliminary purity of>85%. Process value: Pre coarse separation of 60% -70% coarse metal particles significantly reduces the subsequent electrostatic separation load and improves overall efficiency.

Electrostatic Sorting: Purification of Fine Particle Metals

Electrostatic sorting is based on the difference in conductivity between metals (good conductors) and silicon (insulators). In a high-voltage electrostatic field, metal particles are adsorbed and detached from the material flow by the electrode due to conductivity, while silicon powder moves along the original trajectory due to insulation. For fine particles (such as copper powder) separated by air flow density, it is possible to achieve a metal purity of ≥ 98%, overcoming the pain point of difficult recovery of fine powder in traditional processes.

Pulse dust removal

Pulse dust removal adopts a filter bag filtration+pulse cleaning mechanism: the exhaust gas is intercepted by a membrane filter bag with pores ≤ 1 μ m, and the system sprays compressed air pulses every 1-2 minutes to shake off the dust to the ash hopper. The concentration of dust in the treated exhaust gas is ≤ 10mg/m ³, which meets the GB 16297 standard. The collected dust can be reused, achieving zero discharge of solid waste.

Recycling value and significance

The chip recycling production line achieves a metal particle coverage rate of over 90% (particle size 10-500 μ m), copper and gold recovery rates of 95% and 98%, and silicon substrate recovery rate of over 90% through the dual sorting process of airflow and electrostatic separation. The purity of recycled metal meets electronic grade standards, and the purity of copper powder is ≥ 99.5%, which can be directly reused for chip manufacturing; After purification, silicon powder is used in the photovoltaic and semiconductor industries. Single ton processing reduces CO ₂ emissions by 1.2 tons, avoids 10kg heavy metal pollution, and combines high resource efficiency, high-value products, and significant environmental benefits.