ASPEN Metal and Mining

Mining & Metals

Lead & Zinc

We cover the lead and zinc chain end to end — from ore preparation through the roast–leach–electrowin route to special high grade zinc, and across the secondary, residue and lead refining circuits that sit around it.

Lead & zinc process chain

Simplified flowsheet · ASPEN scope

ZINC — ROAST · LEACH · ELECTROWIN FEEDMine & Ore Prep 01Concentration 02ZnS Roasting 03Leaching 04Purification 05Electrowinning SHG ZnMelting & Casting OFF-GAS & ACID 06Gas Cleaning 07Sulphuric Acid RESIDUES & SECONDARIES 08Residue Treatment 09Waelz Processing 10Secondary Zinc LEAD Pb CONCENTRATE 11aLead Smelting 11bLead Refining 12 — CROSS-CUTTING Environmental Systems

Zinc — primary route

01

Mine & Ore Preparation

Run-of-mine handling, crushing and grinding circuits, stockpile and blending strategy, and ore sorting where the deposit justifies it.

02

Concentration

Differential flotation to separate galena from sphalerite, regrind circuits, thickening, filtration and concentrate handling.

03

ZnS Roasting

Fluidised-bed roasting of zinc sulphide concentrate to calcine, with waste-heat recovery and a strong, steady SO₂ stream to the acid plant.

04

Leaching

Neutral and hot-acid leach circuits, and iron removal by the jarosite, goethite or hematite route depending on residue strategy.

05

Purification

Zinc dust cementation in stages to remove copper, cadmium, cobalt and nickel before the solution reaches the cellhouse.

06

Electrowinning

Cellhouse layout, current density and energy balance, cooling, stripping machines and cathode handling.

07

Melting & Casting

Induction melting, alloying to SHG, Zamak or continuous-galvanising grades, and jumbo or ingot casting and stacking.

Off-gas and acid

08

Gas Cleaning

Waste-heat boilers, cyclones, electrostatic precipitators, wet scrubbing and mercury removal to condition roaster gas for the acid plant.

09

Sulphuric Acid

Double-contact double-absorption plants, heat recovery, tail-gas treatment and acid storage and handling.

Secondaries and residues

10

Waelz Processing

Rotary kiln treatment of zinc-bearing residues and EAF dust to produce Waelz oxide, including washing and de-halogenation.

11

Secondary Zinc

Recovery from EAF dust, drosses, ashes and galvanising residues, and integration of secondary feed into the primary circuit.

12

Residue Treatment

Jarosite and goethite handling, stabilisation, metal recovery from leach residues, and tailings and storage design.

Lead

13

Lead Smelting & Refining

Sinter–blast furnace, ISF and direct-smelting routes; drossing, softening, desilverising and refining to LME-grade lead.

Cross-cutting

14

Environmental Systems

Baghouses, scrubbers, fugitive emission capture, effluent treatment and water recycling across the whole complex.