The original 10kt/a vertical retort plant was operated by Fengxian Zinc Products. In August 2001 a 50kt/a expansion was commissioned and included distillation facilities to refine all the zinc from this expansion to SHG. The 10kt and 50kt streams were operated as separate entities. However in 2008 the original 10kt vertical retort plant was replaced by a new plant capable of 80kt/a. This raised the plant's capacity to the current 160kt/a.