Peirce-Smith Converters: Automation, Design, Operation and Environmental Improvements at Kansanshi Copper Smelter

Proceedings, Vol. Proceedings of the 58th Conference of Metallurgists Hosting Copper 2019, 2019

Dyussekenov, Nurzhan

Kansanshi Copper Smelter commenced operation in March 2015. The smelter features four Peirce- Smith Converters (PSCs) operated in a three hot, two blowing configuration. This paper describes some of the process automation and design features implemented to maximize operational and environmental performance. To ensure that the converters were easy to operate, efficient, and were protected in emergency situations such as power failures or loss of tuyere air supply a significant focus was placed on automated sequences initiated by “one button” operator commands or otherwise automatically by the Distributed Control System (DCS). Examples include: main converter roll-in and roll-out sequences; emergency roll-out in the event of power failure; and the charging sequences for reagents (silica and reverts). Other automated features configured for the PSCs were specifically aimed at maximizing converter capacity and reducing the environmental impact from fugitive emissions. These features include: “one button” in-stack charging; automated restriction of blowing rate based on the available acid plant capacity; and fully-automated control logic for the Secondary Ventilation System. In-stack charging allows anode furnace oxide slag to be poured into the PSCs while the converters are still blowing and still sending off-gas to the acid plant. PSC Secondary Ventilation control logic was configured to require minimum input from the operators while ensuring maximum utilization of the available draft from the ventilation system. Highly automated PSC controls contribute to high utilization, averaging 41.2 in-stack hours per day. INTRODUCTION Kansanshi Copper Smelter (KCS) is located near Solwezi at Kansanshi copper mine in Zambia's Northwestern province. The smelter treats concentrate produced at Kansanshi mine as well as Sentinel mine located 150 km west of Solwezi. Four Peirce-Smith Converters (PSCs) are installed at KCS. The nominal capacity of each converter is to treat 350 t of copper matte and produce up to 250 t of blister copper per batch. Normally three PSCs are hot, with two able to operate (produce off-gas), and the third converter on hot standby. The fourth converter is normally under cold repairs. The blister charge size is relatively low for the matte charged due to the unavailability of tank house or other high copper scrap.

Keywords: Copper 2019, COM2019