Introduction to the main process of pyrometallurgical smelting of cathode copper

The main process of cathode copper pyrometallurgy

Before the 1970s, the commonly used copper smelting equipment in pyrometallurgy was blast furnace, reverberatory furnace and electric furnace. The common disadvantages of these processes are high energy consumption, low sulfur utilization rate and environmental pollution. Due to the global energy and environment The problem is prominent, which has prompted the rapid development of copper metallurgy technology since the 1980s. The traditional smelting method has been gradually eliminated, and the enhanced smelting technology represented by flash smelting and molten pool smelting has emerged. The most important breakthrough is oxygen. wide application.

(1) Flash smelting includes three types of flash furnaces of International Nickel Corporation, Outokumpu flash furnaces and vortex top blowing smelting.

Since the Outokumpu flash furnace was put into operation in the Harjavalta smelter in Finland in 1949, 42 have been put into operation so far. The blister copper produced by this method accounts for about 45% of the world's blister copper output, ranking first among all smelting methods. The characteristics of the method are: high smelting speed, low energy consumption, continuous and stable production of high-concentration S02 flue gas suitable for acid production, matte grade up to 60%-70%, etc. High copper slag (containing Cu up to 2.5%) ) can be reduced to 0.3%-0.5% after flotation.

(2) molten pool smelting

Including Teniente copper smelting method, 3 diamond method, Vanukov steelmaking method, Isa smelting method, Norlanda method, top blowing rotary converter method (TBRC), silver copper smelting method, Shuikoushan copper smelting method (Oxygen-enriched bottom blowing molten pool smelting) and other 8 kinds.

2, the hydrometallurgical process

Due to the continuous decline of copper ore grade and the increase of complex ores that are difficult to handle, people pay more and more attention to hydrometallurgy. Solvent extraction electrowinning (SX-EW) technology for copper extraction has been used in the United States, Chile, Zambia, Peru , Australia and Mexico and other places to promote the application, greatly improve the recovery rate of copper and reduce production costs.

Modern copper hydrometallurgy technology includes sulfated roasting-leaching-electrowinning, leaching-extraction-electrowinning, bacterial leaching, etc. It is suitable for heap leaching of low-grade complex ores, copper oxide ores, and copper-containing waste ores. , tank leaching or in situ leaching. The process of wet smelting can be simply divided into 3 steps: leaching, extraction, electrolysis.

Leaching: is the process of separating the copper element in the ore in the form of ions. The ore used for leaching may be a deeper deposit (in-situ leaching), but this is rarely the case. The more common method is heap leaching, The object of leaching is low-grade ores.