To break through the bottlenecks of conventional HPAL—extreme equipment corrosion resistance requirements, high CAPEX/OPEX, and limited Ni/Co recovery—BGRIMM has developed a series of laterite nickel pressure leaching technologies built on inverse leaching and two-stage pressure leaching, providing an economical solution for processing "transitional" laterite ores containing 1.2%–1.5% Ni.

Core Technologies

Inverse Leaching Process – Reverses the traditional sequence by applying atmospheric leaching to limonite and autoclave leaching to serpentine. System temperature drops from 250–270°C to 150°C, and pressure from 4–5 MPa to 0.4–0.5 MPa, eliminating dependence on high-grade titanium equipment and significantly lowering the construction threshold.

Two-Stage Pressure Leaching– Recovers unreleased slurry waste heat from the first-stage limonite HPAL and uses it for "thermal transfer" high-pressure neutralization with second-stage serpentine pulp. This achieves simultaneous iron precipitation and enhanced leaching, solving the challenge of unlocking Ni/Co in serpentine.

Key Performance

Ni & Co recovery: increased from 75%–80% to 90%–92%

Acid consumption: reduced from 850–950 kg/t to 600–650 kg/t

CAPEX: ↓ 35%

OPEX: ↓ 20%–25%

Second-stage serpentine Ni leaching: >97% (total Ni leaching rate up to 93.81%)

Fe & Al in solution: reduced to <1 g/L, lowering alkali consumption in downstream neutralization

Validation & Strategic Value

Bankable feasibility studies show CAPEX and OPEX of less than 10 USD/lb-Ni and 2.6 USD/lb-Ni, respectively—just 40% of HPAL's CAPEX and 65–70% of atmospheric leaching's OPEX. Pilot-scale tests, pilot plant trials, and bankable feasibility studies have been completed for multiple typical laterite nickel deposits in Indonesia and the Philippines. 

As global nickel supply tightens and Indonesia's nickel policy tightens further, this technology series offers a reliable pathway to efficiently monetize low-grade laterite ores and vast stockpiles of transitional resources overseas—especially critical for the EV battery supply chain.