Investigation of hydrogen production in a circulating fast fluidized bed reactor using numerical simulations

Abstract

Oxidative reforming of methane for efficient production of hydrogen in a circulating fast fluidized bed reactor (CFFBR) at low pressure and oxygen distribution has been simulated and evaluated. It has been found that the oxidative reforming of methane is inexpensive alternative route to the conventional steam reforming of methane processes. Also, the potential application of in situ heat integration in the CFFBR is very promising for energy savings. A comparison between co-feed and oxygen distribution configurations is investigated. The performance of the CFFBR with co-feed configuration is profoundly affected by the development of hot spot temperatures along the length of the reactor. The distribution of oxygen mitigates the temperature along the length of the reactor and eliminates the development of hot spot temperatures and reactor thermal runaway. The results show that the combination of oxygen distribution with part of oxygen directly fed into the reactor is efficient configuration for production of hydrogen and produces almost 100% conversion of methane and high yield of hydrogen up to 2.351 at 70% of the dimensionless reactor length. The sensitivity analysis shows that careful selection of the operation conditions is necessary for best reactor performance.