📅 February 2026 · ⏱ 6 min read · BSiO₂ Pty Ltd
The global construction industry faces a carbon crisis. Portland cement production alone releases approximately 6 billion tonnes of CO₂ annually — roughly 8% of total global greenhouse gas emissions. With global concrete production exceeding 10 billion tonnes per year and growing, the pressure to find lower-carbon alternatives to ordinary Portland cement (OPC) has never been greater.
In Australia, the built environment accounts for approximately 23% of national greenhouse gas emissions. The Green Building Council of Australia, Infrastructure Sustainability Council, and major construction clients including governments, universities, and large corporates are increasingly specifying green concrete requirements — including mandatory reductions in embodied carbon — for new projects.
Supplementary cementitious materials (SCMs) are the primary tool for reducing the carbon content of concrete without sacrificing structural performance. And diatomaceous earth is emerging as one of the most promising SCMs — particularly for applications where pozzolanic reactivity, porosity reduction, and durability are priorities.
A pozzolan is a material that, in the presence of water, reacts chemically with calcium hydroxide (Ca(OH)₂) — a by-product of cement hydration — to form additional calcium silicate hydrate (CSH) gel. CSH is the compound that gives concrete its strength and durability. The reaction is called the pozzolanic reaction, and it is the same mechanism exploited by fly ash, silica fume, and metakaolin — the most commonly used SCMs in the Australian construction industry.
The key requirement for a pozzolan is a high content of reactive amorphous silica. This is precisely what diatomaceous earth provides — 80.2% amorphous + opaline silica (confirmed by Agon Environmental XRD, October 2025), with a specific surface area of 494.4 m²/kg (HRL Technology, December 2025) that provides exceptional reactivity.
Peer-reviewed research on Portland cement porous concrete (PCPC) incorporating diatomaceous earth has produced remarkable results that have attracted significant interest from the Australian construction research community.
At 15% DE replacement of OPC — compared to control concrete. Statistically significant (ANOVA p<0.05).
At this substitution level, pozzolanic benefits outweigh dilution effects — the sweet spot for DE in concrete.
Every tonne of cement replaced reduces CO₂ by approximately 800 kg — DE has a much lower embodied carbon footprint.
The compressive strength improvement is the headline result, but researchers have identified a range of additional performance benefits from DE incorporation in concrete:
Research into the use of diatomaceous earth as an SCM in Australian concrete is active and growing. Queensland University of Technology (QUT) and the University of New South Wales (UNSW) are both investigating DE-based concrete formulations. The Australian construction industry's push toward low-carbon concrete — driven by Infrastructure Australia's carbon reduction requirements, the Green Star rating system, and federal procurement policy — is creating strong demand for domestically produced, well-characterised SCMs.
BSiO₂ Pty Ltd is engaged with research institutions and is available to supply product for research programs. Our independently certified product — with confirmed amorphous silica content, particle size distribution, and specific surface area — provides the characterisation data that research programs require.
| Parameter | BSiO₂ Certified Result | Relevance for Concrete |
|---|---|---|
| Amorphous Silica Content | 80.2% (Agon Environmental XRD) | High reactive silica content — key pozzolanic driver |
| Specific Surface Area | 494.4 m²/kg (HRL Technology) | High surface area = high reactivity with Ca(OH)₂ |
| Particle Size D50 | 156 µm (HRL Technology) | Within range for SCM incorporation — grinding may enhance reactivity |
| Cristobalite | Not detected (Agon Environmental) | No crystalline silica concern in mix design |
| Supply format | 1 tonne FIBC bulka bags | Suitable for trial batching and production volumes |
BSiO₂ Pty Ltd welcomes enquiries from concrete technologists, research institutions, and construction companies interested in trialling DE as an SCM. We can supply product at research volumes (50–100 kg bags for trial batching) or wholesale volumes (1 tonne bulka bags) for production-scale trials. Product documentation including full laboratory reports is available.
Contact Richard West for product supply to concrete research programs, trial batching, or production-scale procurement.
