Boral trials MCi Pozzlock in lower-carbon concrete

Boral has trialled concrete containing a lower-footprint cementitious material developed by MCi Carbon in Australia. The work used Pozzlock, a synthetic pozzolan made at MCi’s Myrtle demonstration plant in Newcastle, and progressed to field trials at Boral’s Maldon cement works in New South Wales.

From a demonstration plant to field trials

The significance lies in the industrial route, not a generic promise. MCi Carbon produced the material at Myrtle and Boral moved it into field conditions as part of a project exploring supplementary cementitious materials for infrastructure concrete. SmartCrete Cooperative Research Centre led the programme with Transport for NSW and the University of Technology Sydney.

Pozzlock uses mineral carbonation: CO2 reacts with mineral-rich feedstocks, producing stable carbonates alongside a cementitious material. According to information released about the trial, each tonne of MCi cementitious material can avoid up to 0.5 t of CO2. That is a potential material-level estimate, not a measured reduction across Boral’s entire operation or every concrete mix.

What a new pozzolan must prove

For a cement producer, a field trial is not yet commercial adoption. The central question is whether the material can enter real formulations with repeatable workability, strength, durability, feedstock availability and specification control. The Maldon experience matters because it moves the discussion from producing a sample to concrete performance under applied conditions.

It also shows that decarbonisation routes are not interchangeable. Partial replacement of high-emission components acts in the cement or concrete formulation; mineral carbonation turns CO2 and minerals into a new input. Both require their own technical and commercial validation before scale-up.

The Knergy Angle

Boral’s trial illustrates a practical industry lesson: lowering concrete’s footprint requires combining levers and measuring them where they affect the product. Supplementary materials and mineral carbonation can reduce reliance on carbon-intensive components; in parallel, a clinker kiln must control fuel, flame, oxygen and thermal stability. H2/O2 injection into the pyroprocess can be a complementary lever to improve combustion reactivity or enable alternative fuels, but it does not replace Pozzlock validation or make a mix lower-carbon by itself. The right sequence is to separate the hypotheses: first demonstrate material performance in the mix; then quantify its footprint with clear system boundaries; and, in parallel, evaluate kiln-process measures through a heat balance, fuel analysis and controlled trial.

Limits before scale-up

This trial brings a materials technology closer to infrastructure use without claiming a complete solution. If Boral and its partners repeat the performance at scale, the next filter will be industrial: supply, certification, cost and the ability to integrate the material consistently. For cement plants, that discipline is more useful than an isolated carbon figure: it shows which lever changes the product, which changes the process and what evidence remains before investment.