Scale-up experiments of SO(2) removal and the promoting behavior of NO in moving beds at medium temperatures

The dry flue gas desulfurization (FGD) method was studied, which is a part of the integrated removal of multi-pollutants at medium temperatures. Although dry flue gas treatment is a simple and effective method, it is still a highly empirical-led application technology. A superior desulfurization adsorbent, fine powder of NaHCO(3) (hereinafter called fine NaHCO(3)), was selected by scale-up experiments. A deep understanding of the reaction process and mechanism is then explored, which helps the further optimization of dry desulfurization. Based on the multi-factor experiments for NaHCO(3), the effect mechanism of NO on desulfurization using NaHCO(3) is also proposed. The conversion of SO(3)(2−) → SO(4)(2−) is promoted by the existence of NO. Therefore, a slight decline can be found. According to the influences of the SO(2) concentration and the residence time, it is concluded that the diffusion of SO(2) into the channel of NaHCO(3) is the rate-limiting step. Impressively, the reaction process of reactants was clearly studied by in situ FTIR spectroscopy to determine the whole process. Moreover, the recycling of NaHCO(3) is the main direction for reducing adsorbent consumption in the next step. The predictable insights are beneficial for profoundly understanding the gas composition synergetic interaction for the SO(2) removal by the dry treatment using NaHCO(3).