Bubbling fluidized bed methanation study with resolving the mesoscale structure effects

To elucidate the influence of the changes in the mesoscale structure caused by microscale chemical reactions on the macroscale properties, continuity equations, simplified momentum equations, and pressure‐drop balance equation were introduced into the conventional reactor model to accurately analyze the mesoscale phenomenon in the fluidized bed methanation system, thereby avoiding the limitation due to the use of empirical correlations to describe the mesoscale structure. The reduction of gas volume and the variations of composition and physical properties due to methanation reactions were considered in this model, and the effects of these changes on the mesoscopic flow structures and the macroscopic properties of the entire reactor were further investigated. Several experiments of fluidized bed methanation were also carried out to verify the effectiveness of the proposed reactor model. The results showed that the suggested model can successfully predict the hydrodynamics and reaction behaviors under various operating conditions.