Volume 58

Experimental Investigation of a Novel Simulated Moving Bed Reactor for Stable and Near-Zero-Emission Methane Chemical Looping Combustion Kai Liu, Taixiu Liu, Jiquan Luo, Yang Li, Qibin Liu, Hongguang Jin

Abstract

Chemical looping combustion technology enables low-energy CO2 capture and is a promising low-carbon utilization approach for fossil fuels. As a solid-phase reactant, the oxygen carrier must undergo repeated involvement in the chemical looping process. In contrast to conventional approaches based on circulating fluidized beds or moving beds, this study proposes a simulated moving bed (SMB) reactor using multiple fixed beds arranged in both series and parallel configurations. By implementing a programmed gas?switching strategy, the reactor achieves the approximation of a steady-state moving bed process through inherently unsteady fixed-bed operations. By controlling gas inlet positions, the system can flexibly operate under either co-current or counter-current flow conditions. This novel reactor design features a simplified structure and mitigates the stringent requirements for mechanical strength and wear resistance of oxygen carrier materials typically associated with conventional moving bed reactors, while retaining the advantages of high fuel conversion efficiency and oxygen carrier utilization rate inherent to moving bed systems. We experimentally investigatefundamental reactor characteristics in the reduction stage of the chemical looping combustion process, including the weight hourly space velocity (WHSV) and the corresponding number of fixed-bed reactors in series. The optimal WHSV was determined to be 0.036h-1 for 1073K and three reactors, under which the methane conversion and CO2 selectivity reached 99.23% and 94.99%, respectively. Based on the identified optimal operating conditions, we introduce a gas?switching strategy for the novel SMB reactor. Experimental results demonstrated that the proposed novel chemical looping combustion method exhibits favorable performance and stability, offering a new pathway for the low-carbon utilization of fossil fuels through chemical looping technologies.

Keywords Chemical looping combustion, CO2 capture, simulated moving bed reactor