外加磁场对磁流化床烟气脱硫过程的影响

Influence of Applied Magnetic Field on Flue Gas Desulfurization Process in a Magnetically Fluidized Bed

研究了磁流化床脱硫过程中外加磁场对流化状态、脱硫效率和脱硫产物特性的影响,并分析了磁场强化脱硫的机理.结果表明:随着磁场的增强,磁流化床经历了3个阶段.在鼓泡流化状态下,床层压降不稳定,脱硫效率低;在磁稳流化状态下,床层压降小,脱硫效率快速提高;在磁聚状态下,床层压降较大,脱硫效率提高.兼顾脱硫效率和能源消耗两方面的要求,在磁稳流化状态下进行烟气脱硫是适宜的.此外,对脱硫产物微观形貌和化合物成分的分析表明:磁场改变了铁磁颗粒表面脱硫产物的附着方式,并促进了S(IV)的氧化,提高了SO2的吸收速率,从而提高了磁流化床的脱硫效率.

Influence of applied magnetic field on fluidization behavior, desulfurization efficiency and desulfurization products characteristics were investigated for flue gas desulfurization in a magnetically fluidized bed. Results show that, as magnetic field intensity increases, fluidization behavior presents three different states. When the bed is under bubbling fluidization, bed pressure drop is unstable and desulfurization efficiency is low. When the bed is magnetically stabilized, bed pressure drop is low and desulfurization efficiency increases rapidly. When the bed is magnetically focused, bed pressure drop is high and desulfurization efficiency increases. The magnetically stabilized bed is appropriate for flue gas desulfurization at a high efficiency and low energy consumption. Moreover, based on analysis of microstructure of desulfurization products and compound compositions, magnetic field changes adhering style of desulfurization products on the surface of ferromagnetic particles and enhances oxidation of S （IV） and SO2 adsorption rate, which lead to the increase of desulfurization efficiency.