Non-isothermal modeling of the flue gas desulphurization process using a semi-dry spouted bed reactor

A mathematical model is developed for investigation of SO2 removal in a powder particle spouted bed (PPSB) for non-isothermal operating condition. For this aim, the stream-tube model which was already validated for such systems is applied for hydrodynamics of solid and gas phases, and then by using the conservation laws of mass and energy, the governing equations for gas and solid phases are derived and solved numerically. The published experimental data in the literature are used to validate the accuracy of the proposed model. The results show that the model is capable of predicting the behaviour of this system properly. Also the optimum performance of this system is investigated by studying the effects of different parameters such as bed height, molar ratio of sorbent to acid gas (Ca/S) and inlet concentration of SO2.

Research highlights▶ SO2 removal using hydrated lime slurry in a semi-dry spouted bed reactor was studied using combined stream-tube, mass transfer and non-isothermal models. ▶ Considering heat and mass exchange between phases has significant effect on the precision of the model and the results. ▶ Advantage of this complicated and comprehensive model in which heat and mass exchange between phases and the simple isothermal models lies in its more accurate results.