Mineral Tailings Settlement

PAM for Mining Tailings — Water Recovery That Pays for Itself 20x

A gold mine running five settling ponds and still overflowing in the rainy season is a flocculant problem, not a pond problem. At 7-10 day settling times and 200+ NTU recycled water, the polymer is under-specified for the fines. Move to a 26M MW APAM at around 25 g/ton ore and settling drops to hours rather than days, turbidity to the mid-teens NTU, and water recycling from roughly 45% to 65% — which is what lets a site run three ponds instead of five and free the land. The figures below work that through.

We supply mining-grade APAM to copper, gold, iron ore, and phosphate operations across South America, Africa, Australia, and Southeast Asia. Our factory ships 5,000+ tons annually to the mining sector alone.

PAM Selection by Ore Type

Thickener Operation

The thickener is the heart of tailings management. Without PAM, iron ore thickeners operate at 30-50% of design capacity because fine particles settle too slowly. With our APAM, settling rate improves 10-50x.

• Conventional thickener: APAM 15-20M MW, 15-30 g/ton ore
• High-rate thickener: APAM 20-25M MW, 20-40 g/ton ore
• Paste thickener (dry stacking): APAM 22-28M MW, 30-60 g/ton ore

Paste thickening produces 65-72% solids underflow — no tailings dam needed. This eliminates $100M-500M in dam construction costs. It requires ultra-high MW PAM (25-28M). We produce APAM up to 28M MW, among the highest available commercially.

Worked Example: Gold Tailings, 30,000 ton/day

Modelled, not a delivered project. The comparison below is what the MW step change does on fine gold tailings — the numbers are engineering estimates for a 30,000 ton/day circuit, not measurements from a named site.

The failure mode is a generic 12M MW grade sold into a duty that needs more reach. Fine gold tailings (5-50 µm) need ultra-high MW for effective bridging, and moving to 26M MW is a change you can make without touching dosage or hardware — which is why it is worth ruling out before anyone proposes a second thickener.

Water Recovery Economics

Mining consumes 1-3 tons of water per ton of ore. In water-scarce regions (Atacama, Pilbara, Rajasthan), water costs $1.50-3.00/m³ due to desalination or long-distance pumping.

Batch Consistency for Mining

A single bad PAM batch can shut down a thickener for hours — costing $50,000-200,000 in lost production. Our quality system addresses this:

• MW tolerance: ±0.5M (tighter than industry standard ±1.0M)
• Solid content: ≥90%
• Dissolution time: ≤90 minutes
• Residual monomer: ≤0.05%
• Retained samples: 200-500g per batch, kept 24 months

We export orders to multiple export markets. Mining is our largest sector. We have dedicated mining grades — not repurposed water treatment PAM.

Frequently Asked Questions

Why does my thickener overflow turbidity spike after changing PAM batches?

Almost always a batch consistency issue. A 1M MW difference shifts optimal dosage by 10-20%. Our ±0.5M tolerance minimizes this. If you experience turbidity spikes after a batch change, run a quick jar test to recalibrate — takes 30 minutes. We can also compare your batch against our retained sample to confirm if it is within spec.

How do I handle high-clay laterite tailings?

Clay minerals consume PAM through surface adsorption without contributing to floc formation. Two approaches: (1) Use higher hydrolysis APAM (30-35%) — extra charge overcomes clay interference. (2) Pre-treat with coagulant (alum or ferric chloride, 50-100 g/ton) to neutralize clay charge before adding PAM. Approach 2 typically reduces PAM consumption by 30-40%.

What is the difference between conventional and paste thickening?

Conventional thickeners produce 55-65% solids underflow — flows like liquid, needs a tailings dam. Paste thickeners produce 65-72% solids — behaves like toothpaste, can be stacked without a dam. Paste thickening requires ultra-high MW PAM (25-28M) at higher dosages, but eliminates the cost and liability of a tailings dam entirely.