Fluidization and reaction behavior in chemical looping gasification of lignite

Abstract

Chemical looping gasification (CLG) is a recommended method for lignite gasification, and the product syngas is a mixture of H₂, CO, and other gases. Much attention has been paid to coal gasification using a fluidized bed for syngas production. In this study, the performance of syngas preparation from CLG using a fluidized bed and CaSO₄–CuO as the oxygen carrier was evaluated. To better understand the fluidization process, coal fluidized bed experiments were carried out. Based on the cold-state, syngas obtained from CLG under hot-state conditions was analyzed. The results show that a reaction time of 5 min is recommended for more CO generation. At the same time, a H₂/CO molar ratio of around 1 can be achieved. The energy consumption of syngas generation using CaSO₄–CuO CLG with lignite is 399.75 kJ mol⁻¹, lower than that of syngas generation using the traditional coal reaction with pure oxygen and steam. This indicates that this is an advanced method for preparing syngas, providing a basis for industrial amplification operations.