Development of large steelmaking slag blocks using a new carbonation process

Porous slag blocks (1 m³) were produced by carbonation of steelmaking slag over a period of 12 days. The compressive strength and bulk density of the blocks were 18·4 ± 3·3 MPa and 2·4 g/cm³, respectively. To make a large block, the optimum amount of water and bulk density of the compact were 5·3–6·3 mass% and 2·30–2·37 g/cm³, respectively. The carbonation reaction occurred homogeneously in the blocks, and the amount of CO₂ that reacted with the slag was approximately 6 mass% at all depths from the surface of the block. When left exposed to various weather conditions for 1 year, the blocks showed no cracks or destruction.