Gold Flotation Processing Plant

1. Crushing & Grinding: Dissociate Gold Particles 

Gold is often locked inside sulfide minerals or gangue—so the first step is to break down the ore to expose gold particles:

● Crushing: Jaw crushers (primary) and cone crushers (secondary) reduce large ore chunks (500–800mm) to 20–30mm.

● Grinding: Ball mills grind the crushed ore into a fine partical. This critical step ensures gold particles are fully separated from other minerals.

2. Ore Pulp Conditioning (Reagent Addition)

The ground gold ore pulp is mixed with water to form solid-content slurry. Then 3 types of reagents are added to prepare gold for flotation:

● Collector:  Makes gold’s surface more hydrophobic (e.g., xanthates, dithiophosphates). Gold particles now “stick” to air bubbles.

● Frother:  Creates stable, small air bubbles (e.g., pine oil, methyl isobutyl carbinol). These bubbles carry gold to the surface.

● Modifier: Adjusts pulp pH (e.g., lime to make it alkaline) and suppresses unwanted minerals (e.g., silica) from attaching to bubbles.

3.Flotation Separation: The Core Stage

The conditioned slurry is fed into flotation cells. Agitators mix the slurry and disperse fine air bubbles. The hydrophobic gold-bearing particles attach to the bubbles and rise to form a froth concentrate, which is skimmed off.

● Rougher Flotation:  The first stage aims to produce a primary concentrate.

● Scavenger Flotation: Catches any valuable particles missed in the rougher stage.

●  Cleaner Flotation: Further purifies the rougher concentrate by removing unwanted impurities, resulting in a high-grade final product.

4.Concentrate Cleaning & Dewatering 

The initial concentrate may still contain small amounts of gangue. It’s sent to additional flotation cells (cleaning stages) to remove impurities. Then:

● Thickening: Concentrate is fed into a thickener to reduce water content.

● Filtering: Filter presses or vacuum filters dry the concentrate to 10–15% moisture—making it easy to transport to smelters.