Mapping the operating performance of a novel internally circulating fluidized bed reactor applied to chemical looping combustion

Chemical looping combustion is a promising technology for minimizing the energy penalty of CO₂ capture. To accelerate the scale-up and commercialization of this technology for pressurized operation, the internally circulating reactor (ICR) was recently proposed. ICR integrates the two reactors, cyclones, loop seals and solids transport lines of the conventional chemical looping configuration into a single unit that simplifies design and operation. This work reports the ICR operating performance over a range of operating parameters applied to chemical looping combustion (CLC). The concept proved relatively simple to operate, allowing the oxygen-carrier circulation rate to be controlled over a wide range by varying the bed loading and the air reactor feed rate. Fully autothermal CLC operation was demonstrated as an illustration of the ease of ICR operation. Gas leakage between the two reactor chambers decreased strongly with decreasing solids loading, resulting in CO₂ capture and purity up to 94% for the lowest bed loading. The data showed that significant room for further optimization of the solids transport ports in the reactor exists, which will further increase the CO₂ separation performance. These results demonstrate the promise of ICR concept and provide valuable insights for the design of larger-scale units in future work.