As of March 2021, the Guixi refinery in China, which is owned by Jiangxi Copper Corporation, was ranked as the world’s top copper refinery by capacity. At the time, the Guixi refinery had a refining capacity of 1.1 million metric tons of refined product per year. Shandong Fangyuan, with a capacity of 700 thousand metric tons, was the world’s second largest copper refinery. China is home to more than half of the world’s largest copper refineries.

If you are into table format data : here it is :

Company / RefineryCapacity in 1,000 metric tons
Shandong Fangyuan(China)700
Dave Hubei(China)600
Yunnan Copper(China)500
Birla (India)500
Steclite Refinery(India)460
Pyshma Refinery(Russia)460
Jinchuan (Fangchenggang)(China)450
Toyo. Niihama(Japan)450
Amarillo(United States)450
Chuquicamata Refinery(Chile)450
Onsan Refinery(South Korea)440
Hamburg (Germany)416
El Paso(United States)415
Las Ventanas (Chile)410
Baiyin (China)400
Best(Top) copper producers in the world