The production of Portland cement (PC) is responsible for 8-10 % of the global anthropogenic CO2 emissions. PC and PC-based blends are the most common binder in concrete production (< 99 % of cases). As PC is accountable for 74-81% of the CO2 footprint, substantial climate impact reductions for concrete requires eco-innovation at the cement level.
One of the most promising technologies to lower CO2 emissions consists in partially replacing traditional PC with industrial byproducts displaying cementitious properties, such as blast furnace slag from iron production, or coal combustion fly ashes from power generation, but their availability and properties are rather constrained.
A diversification of local (secondary) raw materials to extend partial substitution of PC is ongoing.