Reaction Mechanism and Distribution Behavior of Arsenic in the Bottom Blown Copper Smelting Process

Abstract

Abstract:The control of arsenic, a toxic and carcinogenic element, is an important issue for all copper smelters. In this work, the reaction mechanism and distribution behavior of arsenic in the bottom blown copper smelting process (SKS process) were investigated and compared to the flash smelting process. There are obvious differences of arsenic distribution in the SKS process and flash process, resulting from the differences of oxygen potentials, volatilizations, smelting temperatures, reaction intensities, and mass transfer processes. Under stable production conditions, the distributions of arsenic among matte, slag, and gas phases are 6%, 12%, and 82%, respectively. Less arsenic is reported in the gas phase with the flash process than with the SKS process. The main arsenic species in gas phase are AsS (g), AsO (g), and As 2 (g). Arsenic exists in the slag predominantly as As 2 O 3 (l), and in matte as As (l). High matte grade is harmful to the elimination of arsenic to gas. The changing of Fe/SiO 2 has slight effects on the distributions of arsenic. In order to enhance the removal of arsenic from the SKS smelting system to the gas phase, low oxygen concentration, low ratios of oxygen/ore, and low matte grade should be chosen. In the SKS smelting process, no dust is recycled, and almost all dust is collected and further treated to eliminate arsenic and recover valuable metals by other process streams.

Effects of Matte Grade on the Distribution of Minor Elements (Pb, Zn, As, Sb, and Bi) in the Bottom Blown Copper Smelting Process

“…Most copper is produced by the pyrometallurgical processes. The oxygen bottom blown copper smelting process is a newly developed intensified smelting process, which has been widely applied in copper production in China in the past 10 years [1,2]. This process was first industrially tested in the Shuikoushan (SKS) smelter in 1990 and was named originally as the "SKS process", which is now also referred to as BBS (bottom blown smelting) or BBF (bottom blown furnace).…”

“…The SKS smelting furnace, which is key to the SKS process, is a horizontal cylindrical reactor similar to the Noranda furnace or the Teniente furnace [1]. However, they still exhibit some development of bottom blown technology, the oxygen-enriched bottom blowing copper continuous converting process has been developed and commercially applied in Dongying Fangyuan II Smelter [6] and Henan Yuguang Smelter, respectively [7], and the process schematic diagram is shown in Figure 2.…”

Development and Application of SKSSIM Simulation Software for the Oxygen Bottom Blown Copper Smelting Process

“…One part is ∆G θ ij , the standard Gibbs free energy of the formation of component i in phase j under the system's temperature and standard pressure. It modifies the impact of temperature on standard Gibbs free energy and can be calculated by Equation (2).…”

“…Later, the process was also called the BBS (bottom blown smelting) or BBF (bottom blown furnace) process. As has been widely discussed in recent years [1,2,6], fundamental studies related to the SKS process are required urgently. Shui et al [7,8] studied the bath surface wave and mixing phenomena in a SKS furnace.…”

“…The oxygen bottom blown bath smelting process is a newly developed intensifying smelting process, which has been widely applied to copper [1,2], lead [3,4], and antimony [5] production in China. The first industrial test of the oxygen bottom blown copper smelting process was carried out in the Shuikoushan (SKS) smelter in 1990 and was thus named the SKS process.…”