Relying on the independently developed combined pyrometallurgical-hydrometallurgical process, the company achieves the efficient recovery of valuable metals such as lead, zinc, and silver in lead ash. The lead recovery rate exceeds 95%. At the same time, the company strictly controls pollutant emissions and meets the national environmental protection standards (lead dust ≤ 0.5mg/m³, SO₂ ≤ 300mg/m³).

1. Pretreatment and Classification

Component Detection: Analyze the content of elements such as Pb (10%-60%) and Zn (15%-30%) in the lead ash through X-ray fluorescence spectrometry, and customize the process plan.

Screening and Briquetting: After removing impurities, use a disc pelletizer to make particles with a size of 3-10mm to improve the smelting efficiency.

2. Pyrometallurgical Smelting (Mainstream Process)

Sintering Roasting - Blast Furnace Smelting

Sintering Process: Oxidize lead sulfide at 850-1000℃, fix arsenic (As₂O₃ volatilizes), and generate a sintered block that can be smelted.

Blast Furnace Smelting: At a high temperature of 1100-1300℃, lead oxide is reduced to metallic lead (purity > 98%), and the lead content in the slag is less than 2%.