Radical Innovation for Zero-Emissions Alumina Production: The AlSiCal Technology

The AlSiCal technology represents a radical innovation in the alumina industry, offering a zero-emissions solution to the global challenges of sustainability and material supply security. By processing non-bauxitic materials (anorthosite rock), AlSiCal co-produces alumina, silica, and calcium carbonate without generating bauxite residue or other solid waste. The technology can operate as a CO2
sink, enabling net-negative CO2 emissions by the production of calcium carbonate via CO2 injection. The technology was invented and proved at Technology Readiness Level 4 (laboratory scale) in a Research and Innovation project funded by the European Commission, the AlSiCal project (GA820911). The technology has shown techno-economic feasibility, environmental benefits, and potentially positive social impacts. This manuscript introduces the AlSiCal technology and explores its potential to reshape the alumina and aluminum value chains, by contributing substantially to international goals of environmental sustainability, economic competitiveness, and social acceptance and engagement.