Refining & Grade Specs

Zinc Refining Methods and Grade Specifications

The transformation of Zinc concentrate into refined products suitable for industrial use requires specialized metallurgical and chemical processes. Zinc is refined into 4 primary commercial forms, each serving specific end-use sectors.

Refining Processes

The primary refining and processing pathways for Zinc include:

1. Flotation concentration
2. Roasting and electrolytic refining (RLE process)
3. Imperial Smelting Process (ISP)

Product Forms and Grade Specifications

Refined Zinc is available in the following commercial forms, each with specific purity requirements:

Quality Standards and Benchmarks

International standards for Zinc products are established by organizations such as ASTM International and various national standards bodies. Pricing is referenced against LME assessments. These standards define minimum purity levels, acceptable impurity limits, and testing methodologies that facilitate international trade.

Refining Capacity and Geography

Global refining capacity for Zinc is concentrated in a limited number of countries. China controls approximately 33% of primary production and plays a significant role in downstream refining. Efforts to diversify refining capacity are a key priority for governments seeking to reduce supply chain dependencies, particularly in the galvanizing steel and iron sector.