Fluidization Dynamics of a New Two-Staged Fuel Reactor for Chemical Looping Gasification

Abstract

A new staged fuel reactor (FR), which integrates a bubbling bed and a spouted fluidized bed, is proposed in the present work with regard to lowering the pressure drop of the staged FR during chemical looping applications. In order to gain insights into the gas−solid fluid dynamics of the new design, a cold experimental setup was established. The fluidization dynamics of the staged FR was investigated based on the pressure pulsation signal analysis using time domain analysis, power spectral density analysis, wavelet analysis, and the Hurst exponent analysis by the R/S method. There are four flow types of funnel-like flow, spout-fluidization, spouting motion, and unsteady spouting motion to be classified, and the transition boundaries of the corresponding flow types were determined. The design provides a way to lower the overall pressure drop of FR and then reduces the fan energy consumption to hold the oxygen carrier particle circulation.

Three-Dimensional Full-Loop Simulation of Gas–Solid Flow Behaviors in a Chemical Looping Gasification System with a Two-Staged Fuel Reactor

“…The simulated CLG system was based on our earlier work 38 and the experimental work of Guo et al 9 Specifically, we replaced the single-stage FR with a two-stage FR and also made corresponding adjustments to other structures to ensure the stability of the whole system. Figure 4 illustrates the schematic and dimensions of the CLG, including an enlarged view of the two-staged FR.…”

“…The MP-PIC method described in Section 2 was implemented in the open-source multiphase flow program MFiX. 35 In order to verify the numerical model, the experiment of Guo et al 9 was simulated. In the experiment, a two-stage FR that combined a bubbling bed and a spouted bed was tested for a CLG system.…”

“…Table shows the parameter settings for different simulation cases. The V FR , W , and H ranges were basically selected based on the experimental conditions, ,, and some adjustments were made to facilitate parameter sensitivity analysis. Note that case 3 is the base case, in which V FR , H , and W are 0.15 m/s, 0.12 m, and 8.4 mm, respectively.…”

“…8 However, the high pressure drop incurred often results in high energy consumption. Recently, Guo et al 9 proposed a structure of two-staged FR in the CLG system which combined a bubbling bed with a spouted bed. They also established a cold-state experimental apparatus for the two-stage FR and explored the fluidization dynamics and flow pattern transitions.…”