Flue gas desulfurization by natural recyclable manganese ore in packed bed reactor and its performance prediction by random pore model.

[Display omitted] • Natural manganese dioxide ore was used as a recyclable sorbent for sulfur dioxide removal. • Kinetic study of the above reaction was accomplished using thermogravimeter apparatus. • Breakthrough curves were obtained in the packed-bed reactor by online mass spectrometer. • Recycling and pore size modification of reacted sorbent by water-washing were performed. • Simulation of packed-bed lifespan by random pore model and kinetic parameters was done. Various grades of manganese dioxide ores, as a natural recyclable sorbent, can be used in dry flue gas desulfurization (FGD) at moderate temperatures (350–450 °C). This research provided low- and high-grade manganese dioxide ores to examine SO 2 removal in a packed bed reactor. To obtain characteristic parameters of mineral sorbents, XRD, XRF, BET, and mercury porosimetry were employed. Then, kinetic parameters of desulfurization reaction were determined using thermogravimeter analyzer (TGA) and random pore model (RPM) for a single pellet. In desulfurization experiments of simulated flue gas in a packed bed reactor and mass spectrometer (MS) apparatus, the breakthrough times were measured under various operating conditions. The onset of these breakthrough times or life-time of MnO 2 reactor for the SO 2 removal was predicted successfully by RPM for a packed bed reactor using related kinetic constants from TGA. In addition, reacted sorbets were recycled multiple times after washing with water. Not only does this simple method separate MnSO 4 from unreacted sorbents as a valuable byproduct to reduce the FGD cost, but it also improves pore size distribution (PSD) of mineral MnO 2 by creating large pores. Modified PSD of this recycled sorbent caused increased breakthrough time. [ABSTRACT FROM AUTHOR]