Attrition behavior of calcium-based waste during CO2 capture cycles using calcium looping in a fluidized bed reactor

The effects of reaction temperature, fluidization number, particle size and number of calcination/carbonation cycles on attrition and CO2 uptake characteristics of carbide slag during the calcium looping cycles were investigated in a fluidized bed reactor. The attrition behaviors of carbide slag and limestone were also compared. Higher calcination temperature in 850-950 degrees C improves the attrition rate of carbide slag particles. CO2 uptake capacity of carbide slag increases with fluidization number in carbonation. As fluidization number increases from 7 to 15, the mean diameter of carbide slag particles decreases by 4% and the attrition rate increases by 1.7 times after 10 cycles. Smaller particles show higher attrition resistance during the cycles. The breakage of larger particles of limestone is more severe than that of carbide slag during the cycles. CO2 uptake capacity of the carbide slag is practically identical to that of limestone in short carbonation duration (e.g. 5 min) during the cycles. The effects of the number of calcination/carbonation cycles on the mean diameter and the attrition rate of carbide slag are less than those of limestone. Carbide slag possesses higher attrition resistance than limestone during the multiple CO2 capture cycles. (C) 2016 The Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.