Red Mud Should Not Be Hidden in Concrete: Taking It Apart with ARBOK RedMud

Red mud (bauxite residue) accumulates at more than 4 billion tonnes worldwide and grows by about 150 million tonnes a year, while only 2–5% of it is used. A recent proposal from scientists in Ireland mixes red mud into concrete, replacing 20–30% of cement. We compare this route with ARBOK RedMud, a containerised process that separates red mud into caustic soda, process water and a dry mineral residue at 2–3 kWh/m³ without reagents, membranes or consumables. For a line of 10 modules handling about 1,500 tonnes of mud a day, caustic soda and water alone bring about USD 5,000 a day and avoided disposal a further USD 15,000–75,000, or USD 7–26 million a year before any sale of the residue.