Thermal management for chemical looping systems with chemical production

Chemical looping technology is a promising pathway to realize a clean production of value-added chemicals with less energy penalty. Its core concept, utilizing heat storage in the cycled solid materials to maintain an efficient operation, needs further confirmation. Here, a combined thermal management method is firstly proposed to achieve an autothermal operation for chemical looping system. New dual fast fluidized bed reactors with optimal reaction temperatures are designed to match the redox reaction rates, while heat integration and exergy cost assessment are conducted to locate the source of thermodynamic irreversibility and interpret the cost formation process. The heat transfer between high temperature exhaust gases and low temperature inlet streams contributes to the main thermodynamic irreversibility and exergy cost. The external energy demand for system gets a maximum 62.37% decrement, the exergy efficiency shows a maximum 9.00% increment and the unit exergy cost for oxygen production gains a maximum 42.18% decrement. (C) 2019 Elsevier Ltd. All rights reserved.