Impact of CaO and CaCO3 addition on agglomeration/defluidization and heavy metal emission during waste combustion in fluidized-bed

Under different operating parameters the addition of Ca compounds (either CaO or CaCO3) could prolong defluidization time. The emission trends of the different heavy metals were largely similar despite having different volatility properties. After the occurrence of defluidization in the sand bed, the heavy metal emission increased significantly. When CaO or CaCO3 was added, the majority of the results suggested that the heavy metal emission concentration is lower than that in the case when no Na was added. The presence of CaO or CaCO3 shows equal potential in reducing the heavy metal emission. Comparison of the impact of CaO or CaCO3 on the agglomeration/defluidization process and heavy metal emission shows CaCO3 to be more effective in inhibiting defluidization.