Effects of oxygen carrier mole fraction, velocity distribution on conversion performance using an experimentally validated mathematical model of a CLC fuel reactor

Highlights: • An experimentally validated computer model has been implemented in User Define Functions. • The validated model is used for a numerical study of CLC using CaSO₄ as oxygen carrier and H₂ as fuel. • Effects of mole fraction of CaS, temperature, fuel superficial feeding velocity were discussed. • The fuel feeding velocity has significant effect on the flow and conversion performance. • Operating temperature mainly affects the fuel conversion. - Abstract: Due to the severity of the worldwide climate change problem and the ocean acidification problem, chemical looping combustion (CLC) technology is studied worldwide by researchers in order to meet the urgency of carbon emission reduction after its concept has been put forward. An experimentally validated computer model has been implemented in Ansys-Fluent code with the most appropriate kinetic model implemented in User Define Functions. The validated model has been used to carry out a numerical study on a model fuel reactor using CaSO₄ as oxygen carrier and H₂ as fuel; is conducted in the present work. Effects of mole fraction of CaS, operating temperature, superficial feeding velocity magnitude of fuel and the diameter of oxygen carrier particles were discussed. The results indicate that the superficial feeding velocity of gaseous fuel has significant effects on the flow condition with fuel reactor and conversion performance, while operating temperature mainly affects the fuel conversion. The effects of particle diameter on flow condition within FR are obvious but insignificant on conversion performance of fuel. The mole fraction of CaS has the least effect among these three parameters. Several velocity distributions are also studied. The rectangle-trianble distributor results in better bubbles distributions, but the gain of higher fuel conversion rate is insignificant due to the low chemical activity of OC used in this study.