1. Upstream – Zinc Ore Smelting
China has abundant zinc ore reserves, accounting for nearly 20% of the world’s total, second only to Australia. Moreover, China is also a major producer of zinc ore, with its output accounting for more than one-third of the global total, ranking first in the world. The smelting process involves: extracting and refining zinc ore to obtain zinc sulfide concentrate, which is then reduced into pure zinc using either pyrometallurgical or hydrometallurgical methods to produce zinc ingots.
In 2022, China’s zinc ingot output reached 6.72 million tons. The cost of zinc ingots ultimately determines the price of spherical zinc powder, which is generally estimated at 1.15 to 1.2 times the price of zinc ingots.
2. Zinc Powder – Atomization Method
In a reverberatory or converter furnace, zinc ingots with a purity of 99.5% are heated to 400–600°C to be melted. After melting, the zinc is transferred to a refractory crucible and atomized under heating and insulation conditions, with compressed air at a working pressure of 0.3–0.6 MPa. The atomized and cooled zinc powder is collected in a zinc powder dust collector and then fed into a multi-layer vibrating screen. Through the vibration of the screen body, the zinc powder is separated into different fineness grades and moved into packaging drums.
3. Zinc Powder – Ball Milling Method
This includes both dry and wet methods, resulting in dry flaky zinc powder or paste-like flaky zinc powder. For example, wet ball milling can produce a paste of flake zinc powder slurry. Atomized zinc powder is mixed with aliphatic hydrocarbon solvents and a small amount of lubricant, then ground in a ball mill. When the desired fineness and flake shape are achieved, the slurry is discharged and filtered to form a filter cake with a metal content of over 90%. After mixing, the filter cake becomes zinc powder slurry used in coatings, with a metal content of over 90%.
Post time: May-30-2025
