Utilization of copper tailing for autoclaved sand–lime brick

The influences of the batch ingredients and the autoclaving processes on the properties of autoclaved sand–lime brick from low SiO2 content copper tailing were studied. The results show that the copper tailing with low content of SiO2 can be used to produce autoclaved sand–lime bricks meeting GB11945-1999 for Mu 15 sand–lime brick, if only the proportion of the copper tailing in the brick batch does not exceed 50% (% by mass) and appropriate proportions of river sand and sand powder are added to compensate for the low SiO2 content. XRD and SEM analyses show that the main hydrothermal reaction products in the brick are 0.9 nm, 1.1 nm and 1.4 nm tobermorite phases, and the andradite in the copper tailing nearly does not take part in the autoclaving reaction.