Filter presses for mining: tailings volume reduction and dry stacking, gold, copper and iron concentrate dewatering, abrasion-resistant cloth and feed pump selection.

Tailings and Concentrate Dewatering

Part of mining and mineral processing.

Quick answer: In mining, a filter press is bought for one of two reasons — to shrink tailings volume and recover process water, or to dry a saleable concentrate to a transportable moisture. The two jobs need different machines. Tailings duty is dominated by abrasion and cycle count; concentrate duty is dominated by achieving a moisture target without over-drying into a dust problem.

Tailings: the job is water, not solids

Filtered tailings (often called dry stack) exist because tailings dams fail and because water is scarce. The engineering question is rarely “can a filter press dewater this” — it usually can — but whether the cycle count needed to keep up with the mill is economic.

What decides that:

  • Fines content. Ultra-fine tailings from regrind circuits filter slowly and blind cloth quickly. Cycle time, not plate area, becomes the limiting factor.
  • Abrasion. Silica-rich tailings wear cloth, feed pump wet ends and plate sealing faces. Consumables, not capital, dominate the ten-year cost.
  • Water balance. If filtrate is returned to the mill, the value of recovered water often justifies the press on its own in arid regions.

More detail: tailings dewatering and volume reduction, and the honest comparison in filter press vs decanter centrifuge for tailings.

Concentrates: hitting a moisture window

Gold, copper and iron concentrates are usually sold on a moisture specification. Too wet and you pay freight on water and risk cargo liquefaction; too dry and you create dust losses and handling problems. Membrane (diaphragm) plates earn their cost here because the squeeze step gives you control over the last few percent.

See automatic concentrate filter presses and concentrate dewatering practice.

Cloth is the consumable that decides your uptime

In mining duty the filter cloth is replaced far more often than anything else on the machine, and the wrong cloth costs more in lost cycles than it ever saved in purchase price. Monofilament weaves release cake better and resist blinding; multifilament and staple weaves capture finer particles but blind faster on abrasive feeds.

Relevant reading: filter cloth for mining concentrate and tailings, what causes cloth blinding, and how often cloth should be replaced.

Feed pumps take the same abuse

A mining feed pump has to move a thickened, abrasive slurry against a pressure that climbs through the cycle. Pump choice is not an accessory decision — an undersized or wrong-type pump produces long tails at the end of every cycle and wears out predictably.

See slurry pumps for mineral processing and how to choose a feed pump.

Equipment

Frequently asked questions

Is filtered tailings always better than a tailings dam?

Not automatically. Dry stacking removes dam failure risk and recovers water, but it adds continuous operating cost and needs a stacking area and equipment. It becomes clearly favourable where water is expensive, seismic risk is high, or regulators require it.

How much can a filter press reduce tailings volume?

It varies with the ore and the starting slurry density, so anyone quoting a single number without seeing your material is guessing. The meaningful figure is your cake moisture after a test on your actual tailings, which is why we ask for a sample.

Do I need membrane plates for tailings?

Often no. Tailings are usually stacked rather than sold, so the moisture target is set by stackability and haulage, not by a sales specification. Recessed chamber plates frequently reach it. Membranes matter more on concentrates.

Why does my cycle time get longer over the first months?

Almost always progressive cloth blinding from fines and scale, sometimes combined with feed density drift. It is a cloth and conditioning problem, not usually a machine fault.

Send us a tailings or concentrate sample and we will run a filtration test before recommending anything — see filtration testing and trials, or contact us.