From Mine Tailings to Technology: Cementitious Strategies for Lithium, Alumina & Iron Mining By-Products

Western Australian School of Mines Symposium | April 2025

As with any mining process, metal production from all mineral deposits incurs the inevitable production of mineral residues. The global push for sustainable resource management has placed increasing pressure on the mining industry to find viable solutions for processing by-product residue materials. Lithium mining, crucial for battery technologies, generates substantial by-products, including lithium aluminosilicate residue (LASR). While traditionally considered an abundant “waste material”, especially in Western Australia, LASR has the potential to be re-engineered into value-added products through embodiment into cements. One particular example is via geopolymerisation, a low-carbon alternative to conventional Portland cement with comparable mechanical properties.

At the 3rd Western Australian School of Mines: Minerals, Energy and Chemical Engineering Symposium, Ramon Skane presented work exploring how lithium mine by-products can be re-engineered into value-added construction materials through geopolymerisation.

Characterising Lithium Processing Residues

The work focused on detailed materials characterisation of lithium aluminosilicate residues using:

• X-ray fluorescence (XRF)

• Particle size distribution (PSD)

• Quantitative X-ray diffraction (XRD)

• SEM / EDS microstructural analysis

The LASR analysed consists primarily of an aluminosilicate (HAlSi2O6) – a by-product from β-spodumene ore leaching – alongside α-quartz, β-quartz and minor phases including bassanite, rutile, lithium sulfate, gypsum, sodium ferrite and an amorphous fraction. Such mineralogical composition suggests potential suitability for alkali-activated systems, provided reactivity and particle distribution are appropriately managed.

From Residue to Binder

The research investigated encapsulating LASR within geopolymer composites — a low-carbon alternative to conventional Portland cement.

Preliminary synthesis results demonstrated that lithium processing residues can be incorporated into geopolymer systems to produce structurally relevant compressive strengths within ranges comparable to conventional cementitious binders.

While optimisation remains system-specific, the findings confirm technical feasibility.

Importantly, this approach:

• Reduces reliance on clinker-based binders

• Diverts mineral residues from disposal pathways

• Embeds value within existing mining supply chains

  
  

A Broader Mine Waste Framework

The study also situates LASR within a wider mine-waste valorisation landscape.

Comparable opportunities exist across:

• Kaolin clay mining residues

• Fly ash and coal combustion by-products

• Red mud from alumina processing

• High-amorphous metallurgical slags

The common denominator is mineralogical potential.

When properly characterised, many residues contain reactive aluminosilicate phases capable of contributing to cementitious systems.

The barrier is not just the chemistry.

It is process control, standardisation, and durability validation.

Engineering the Transition

As critical minerals production scales, residue volumes will grow in parallel.

Transforming tailings into engineered construction materials offers:

• Reduced disposal liabilities

• Lower embodied carbon in downstream infrastructure

• Diversified revenue streams for mining operators

But success requires rigorous characterisation, controlled geopolymer synthesis and an understanding of long-term performance.

Residue utilisation must be engineered, not assumed.

Reformix continues to explore pathways for converting mining by-products into technically validated, commercially viable material systems.

The work continues.