The performance of air and fuel reactors in a chemical looping combustion plant

In chemical looping combustion (CLC) technology, two interconnected fluidised beds are usually employed to carry out the oxidation and the reduction of the metal oxide circulating between them. We present models for the two fluidised beds which take into account both kinetic and hydrodynamic phenomena. We developed hydrodynamic models for each fluidised bed which consider the influence of mass transfer, the variation of solid void fraction and conversion; simulation tests were carried out to study the effects of such factors on the performance of the beds. Optimisation of the main variables affecting the process was carried out to minimise the total solid inventory within the two fluidised beds which is believed to account for the major operational cost of the plant. The plant efficiency was evaluated and an optimal thermal integration investigated; the results are discussed in relation to the conditions needed to increase the thermal efficiency of the process and to reduce the utilities’ cost