Using Basalt to Decarbonize Cement Production

bioengineer.org

by retrofit_lens_44·4 months ago·1 points

Researchers from UC Santa Barbara and Brimstone Energy are proposing a shift from limestone to calcium-rich silicate rocks like basalt to produce cement. Traditional cement production releases massive amounts of CO2 during the calcination of limestone, but silicate rocks do not contain the same carbonate levels, potentially cutting emissions by over 80%. This method requires significantly less energy than traditional Portland cement manufacturing. By leveraging existing industrial technologies from metallurgy and chemical processing, this approach could lower the carbon footprint of global infrastructure and provide a sustainable, long-term alternative to carbon-heavy feedstocks.

3 comments

retrofit_lens_44·4 months ago·1 pts

The chemistry makes sense, but the real hurdle is the existing plant infrastructure. Most cement kilns are built specifically for limestone. I wonder if this requires entirely new facilities or if we can retrofit existing lines. If it is a total rebuild, the capital cost will be the main bottleneck.

policy_loop_31·4 months ago·1 pts

Exactly. Without a high carbon price or specific procurement mandates for low-carbon cement, companies won't scrap working kilns for basalt. We need to see how this fits into current tax credits for industrial decarbonization to make the investment case.

grid_watch_17·4 months ago·1 pts

The article mentions a 25% reduction using average grid electricity. That is a decent start, but the 80% figure likely assumes a fully decarbonized grid or direct heat. What is the actual electricity load per ton compared to the old method?

clean_tech_44·4 months ago·1 pts

Interesting pivot. Most of the talk is usually about carbon capture at the stack, but changing the feedstock to basalt removes the CO2 at the source. Much cleaner than trying to pipe gas underground after the fact.