Akademik Veri Yönetim Sistemi
ENERGY & FUELS, cilt.27, sa.3, ss.1466-1472, 2013 (SCI-Expanded)
The phosphate rock was calcined at temperatures ranging between 775 and 850 degrees C in a fluidized bed using air. The changes in the pore structure and surface area of the calcined phosphate samples were determined by a mercury porosimeter and Brunauer-Emmett-Teller (BET) analysis. It was determined that the calcined phosphate samples at 850 degrees C for 8 min have the highest surface area, particle volume, and porosity. Then, the reaction kinetics of SO2 with calcined phosphate sample (at 850 degrees C for 8 min) was investigated in a differential fluidized bed by changing the sulfation temperature and SO2 and CO2 concentrations. It was observed that the sulfation ratio increased with an increasing temperature and SO2 concentration but decreased with an increasing CO2 concentration. The sulfation reaction was well-represented by a shrinking core model, which can be divided into two regions with different rate controlling steps. For low conversions, the controlling step was found to be the chemical reaction at the interface but the diffusion through the product layer for high conversion. The activation energies for the chemical reaction at the interface and the diffusion through the product layer were calculated as 92 and 197 kJ mol(-1), respectively.