Reuse the Bed Ash from Circulating Fluidized Bed Combustion on Mortar Mixture

This paper investigates mortars consisting of various circulating fluidized bed combustion (CFBC) bed ash contents. The CFBC bed ash used in this study was obtained from Taiwan’s petroleum industry. This study presents experimental results on the flowability, compressive strength, drying shrinkage, scanning electronic microscopy (SEM) and mercury intrusion porosimetry (MIP) of mortar samples containing CFBC bed ash. The initial surface absorption tests (ISAT) and rapid chloride penetration test (RCPT) of mortar were used to measure water absorption and the ability to resist chloride ion characteristics for different mortar samples containing CFBC bed ash. CFBC bed ash is X-ray amorphous and consists of SiO2, Al2O3 and CaO compounds. As more cement is replaced by CFBC bed ash, the ISA rate increases but the compressive strength decreases. On the other hand, replacing sand with CFBC bed ash increase the compressive strength increases, but the ISA rate decreases. As the CFBC ash content increases, the slump decreases due to a reduction in the fineness modulus and the negative effect of CFBC particles. This study also shows that utilizing the proper amount of CFBC bed ash in mortar significantly improves sulfate resistance.