Overview of Pyrometallurgical Recovery Process for Precious Metals
Types of Precious Metals
Precious metals include gold (Au), silver (Ag), platinum (Pt), osmium (Os), iridium (Ir), ruthenium (Ru), rhodium (Rh), and palladium (Pd). These eight metals are highly valued due to their rarity and expense.
Waste Materials Containing Precious Metals
Scrap items and off-cuts containing precious metals can be found in various sources such as:
– Wasted electrical and electronic equipment, including old mobile phone boards, chips, flex circuits, SIM cards; discarded computer motherboards, CPUs, RAM sticks, connectors.
– Jewelry scrap.
– VCD player boards, electronic components, etc.
– Gold-plated items and electronic components.
– Various silver-containing waste materials.
Process Flow for Pyrometallurgical Recovery of Precious Metals from Electronic Waste
The recovery process for precious metals from electronic waste can be divided into two stages: pre-treatment and post-treatment. Pre-treatment involves mechanical processing methods, while post-treatment includes pyrometallurgy, hydrometallurgy, and bioleaching.
Pyrometallurgical processes mainly consist of incineration smelting, high-temperature oxidation smelting, slag flotation technology, and arc furnace sintering.
Basic Principles of Pyrometallurgical Processes
The fundamental principle of pyrometallurgy is to use high temperatures within a metallurgical furnace to decompose non-metallic substances, allowing precious metals to melt into other metallic melts or molten salts, which are then separated. Non-metallic materials, primarily from printed circuit boards, typically separate as slag, whereas precious metals form alloys with other metals, which are subsequently refined or processed via electrolysis. Key pyrometallurgical techniques include incineration smelting, high-temperature oxidation smelting, slag flotation, and arc furnace sintering.
Characteristics of Pyrometallurgical Recovery Process for Precious Metals
This method is characterized by its simplicity and high recovery rate. It can handle all forms of electronic waste, with the primary precious metals recovered being Au, Ag, and Pd.
For more information about the pyrometallurgical recovery process for precious metals, contact Guanma Machinery. We provide specific solutions based on project analysis!
