Strategies for arsenic pollution control from copper pyrometallurgy based on the study of arsenic sources, emission pathways and speciation characterization in copper flash smelting systems

Huihui Zhou; Guijian Liu; Liqun Zhang; Chuncai Zhou; Md Manik Mian; Ayesha Imtiyaz Cheema

doi:10.1016/j.envpol.2020.116203

Strategies for arsenic pollution control from copper pyrometallurgy based on the study of arsenic sources, emission pathways and speciation characterization in copper flash smelting systems

Environ Pollut. 2021 Feb 1:270:116203. doi: 10.1016/j.envpol.2020.116203. Epub 2020 Dec 8.

Authors

Huihui Zhou¹, Guijian Liu², Liqun Zhang³, Chuncai Zhou⁴, Md Manik Mian¹, Ayesha Imtiyaz Cheema¹

Affiliations

¹ CAS Key Laboratory of Crust-Mantle Materials and the Environments, School of Earth and Space Sciences, University of Science and Technology of China, Hefei, 230026, China; State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, The Chinese Academy of Sciences, Xi'an, Shanxi, 710075, PR China.
² CAS Key Laboratory of Crust-Mantle Materials and the Environments, School of Earth and Space Sciences, University of Science and Technology of China, Hefei, 230026, China; State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, The Chinese Academy of Sciences, Xi'an, Shanxi, 710075, PR China. Electronic address: lgj@ustc.edu.cn.
³ School of Resource and Environmental Engineering, Anhui University, Hefei, 230601, China.
⁴ School of Resources and Environmental Engineering, Hefei University of Technology, Hefei, 230009, China.

PMID: 33321434
DOI: 10.1016/j.envpol.2020.116203

Abstract

Arsenic in copper flash smelting (FS) systems not only affects the quality of products but also poses significant technological and environmental problems. Based on the assessment of arsenic mass partitioning in the FS system, arsenic elimination in off-gassing and tailings is 22%, and most of the arsenic output (69%) is recycled in the FS system. Circulating arsenic, especially arsenic in recycled dust and slag concentrate, is the key reason for high-arsenic-content feed. Dust-type recycled materials (RMs) contribute much more arsenic to the feed than slag-type RMs. Flash smelting furnace electrostatic precipitator (FSF ESP) dust contributes makese the largest contribution to arsenic among the dust-type RMs of mixed dust, especially trivalent arsenic, followed by FSF and flash converting furnace waste heat boiler (FCF WHB) dust, which contributes pentavalent arsenic. FCF WHB dust exhibits a relatively low arsenic content, consisting mainly of As(V)-O. Slag-type recycled materials contribute As(V)-O to the total feed, and As(III) originates from copper concentrates. Considering the arsenic contribution and environmental risk, reducing the recovery of FSF ESP dust can greatly decrease the arsenic grade of FSF feed and volatile As₂O₃. As one of the main arsenic sources in feed, FSF slag concentrate should be carefully disposed of if separated from feed materials because of its high arsenic-related environmental risk. In contrast, WHB dust and FCF slag are more suitable as RM due to their high copper content and low arsenic risk.

Keywords: Arsenic; Chemical speciation; Flash copper smelting; Mass partitioning; Occurrence mode.

MeSH terms

Arsenic* / analysis
Copper / analysis
Dust
Environmental Pollution
Metallurgy

Substances

Dust
Copper
Arsenic