关键词: 铁尾矿, 加气混凝土, 托贝莫来石, 性能

Abstract: Autoclaved aerated concrete was prepared with lean vanadium and titanium magnetite tailing as main raw material and characterized, and the influential factors on the preparation were examined. The results showed that the optimal conditions of preparation were obtained as the mass ratio of iron ore tailing to silica sand, lime, cement and gypsum at 45:20:19:14:2, content of Al powder 0.09% and mass ratio of water to materials 0.60. Under the optimal conditions, the compressive strength of final concrete product was 3.52 MPa, and dry bulk density 620.8 kg/m3, which accorded with the national standards of autoclaved aerated concrete. The product was mostly composed of low crystallinity and amorphous C-S-H gel and hydrates, iron ore tailing particles and ettringite before high pressure steaming treatment. A large amount of tobermorite with good crystallization formed in the autoclaved product, and mixed with the rest of hydration products, leading to the crystallized network of dense mesh structure with the crystal clusters and aggregates of other aquatic products, which promoted the performance of autoclaved aerated concrete.

Key words: iron ore tailing, autoclaved aerated concrete, tobermorite, property