Original Article

Distribution behavior and deportation of arsenic in copper top-blown smelting process

¹ State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization, Kunming University of Science and Technology, Kunming 650093, China
² Faculty of Metallurgical and Energy Engineering, Kunming University of Science and Technology, Kunming 650093, China

^* e-mail: libokmust@163.com

Received: 22 November 2022
Accepted: 12 August 2023

Abstract

In recent years, the impurity content in copper concentrate increases gradually with the consumption of high-grade copper ore. When the arsenic content in the raw materials increases, large amounts of arsenic enter the sulfuric acid system, resulting in large amounts of waste acid that put great pressure on production and environmental protection. Using the distribution characteristics of arsenic in each phase, the possibility of enriching arsenic in the form of stable arsenates in the slag was investigated to enrich arsenic in the form of stable arsenates in the slag. It is shown that increasing CaO content in slag at relatively low temperatures, controlling the slag type and changing the slag composition effectively improved the ability of the slag to absorb arsenic. Based on a theoretical analysis used to optimize the process parameters and determine a reasonable slag type, an oxygen-enriched top-blown smelting experiment was conducted with mixed copper concentrates. The mechanism of arsenic fixation in smelting slag at a smelting temperature of 1180 °C (1453 K) was investigated, and the results showed that the As content in slag was increased by 20∼50% and decreased by 10∼30% and 10∼20% in the dust and matte, respectively. Thus, arsenic is fixed in silicate in the form of stable arsenate, which can be an effective and safe treatment solution for copper smelting processes.