HPSA™

Selective Mineral Liberation at Coarser Particle Sizes

High-Pressure Slurry Ablation (HPSA™) is a patented mechanical liberation technology that directs opposing, high-velocity slurry streams into a collision chamber. The resulting particle-to-particle impacts fracture the material along natural grain boundaries and differences in mineral hardness. Unlike conventional grinding, HPSA does not require grinding media or chemical reagents and concentrates mechanical energy directly on the particles that need to be liberated.

This selective breakage mechanism can liberate valuable minerals at coarser particle sizes while limiting unnecessary breakage of the surrounding gangue. Reducing overgrinding also means fewer fines and slimes, a cleaner particle-size distribution and improved conditions for downstream flotation, leaching, gravity separation, magnetic separation or sizing. Where valuable minerals or contaminants occur as coatings on harder particles, HPSA can also remove softer surface layers, expose cleaner mineral surfaces and improve separation efficiency.

HPSA can be installed at several points within an existing flowsheet. Potential positions include ball mill feed or partial mill replacement, cyclone underflow, regrind feed, cyclone overflow ahead of flotation, intermediate process streams and tailings retreatment circuits. Its modular, skid-mounted configuration allows the technology to supplement existing grinding capacity, relieve a constrained mill or treat previously uneconomic tailings and low-grade stockpiles without requiring a completely new processing plant.

Key Benefits

Selective Liberation and Improved Recovery

By exploiting hardness contrasts and natural mineral boundaries, HPSA directs breakage towards mineral associations rather than indiscriminately reducing the size of the entire feed. Coarser liberation can improve valuable-mineral exposure while preserving a more favourable particle-size distribution. This can increase concentrate grade and recovery or allow downstream separation stages to operate more efficiently.

Lower Energy Consumption and OPEX

HPSA eliminates grinding media and operates without chemical reagents within the liberation stage. Lower energy intensity, reduced consumable demand, fewer mechanical components and simpler maintenance can significantly decrease operating expenditure. Disa reports an energy requirement of approximately 3–10 kWh/t, wear costs below US$2/t and equipment availability above 95%, although actual results depend on the ore and operating conditions.

Reduced CAPEX and Flexible Integration

The modular, skid-mounted system can potentially replace or supplement selected grinding and regrinding duties while occupying a smaller footprint than conventional milling infrastructure. Controls, electrical systems, piping, collision chambers, sump and guarding can be incorporated into the unit, simplifying site installation. Depending on the application, this may reduce the need for large foundations, grinding-media handling systems and additional downstream stages. Installation can be completed in weeks rather than months, shortening the route from project approval to production.

Cleaner Mineral Surfaces and Better Downstream Performance

Particle-to-particle collisions can detach softer gangue coatings, oxidised layers or surface-bound contaminants from harder host particles. This surface-cleaning effect can expose valuable mineral surfaces to collectors or lixiviants, improving flotation and leaching response. It can also support applications such as phosphate upgrading, graphite purification, uranium remediation and filter-sand regeneration, where surface coatings directly affect product quality or separation performance.

Mining Applications

HPSA has potential across copper, nickel, zinc, lead and molybdenum circuits; gold, silver and PGM processing; lithium, graphite and rare-earth mineral beneficiation; and iron ore, phosphate, potash, chromite, fluorspar and mineral-sands applications. It is also particularly relevant for tailings, middlings and low-grade stockpiles containing valuable minerals that remain locked or surface-coated after conventional processing.

The strongest opportunities are generally found in circuits affected by high grinding energy consumption, excessive fines generation, poor flotation selectivity, incomplete surface cleaning or restricted mill capacity. For these applications, HPSA can be evaluated as a selective liberation stage, with ore-specific testwork used to determine its optimum flowsheet position and quantify the expected improvements in recovery, grade, throughput, CAPEX and OPEX.