Thermodynamic analysis and process simulation of syngas production from methane using CoWO4 as oxygen carrier

Cobalt tungstate (CoWO4) is proposed as an oxygen carrier (OC) in a Chemical Looping Partial Oxidation of methane process (CLOP) to produce syngas (CO + H2). A thermodynamic analysis and process simulation of the CLPO of CH4 by CoWO4 as OC is presented. HSC and Aspen Plus software were used for the equilibrium calculations and process simulation, respectively. A basis of 4 kmol/h of CH4 was employed. Sensitivity analyses were performed to determine optimal operating process conditions. Results in the fuel reactor indicate no carbon formation and a T = 752 °C and a feed of CoWO4 = 1.4 kmol/h, thus producing 6.68 and 3.20 kmol/h of H2 and CO, respectively (H2/CO = 2). While, the oxidation reactor resulted in T = 502 °C and a H2O feed of 6.6 kmol/h, producing 5.6 kmol/h of pure H2. Thermal efficiency (86-92%) and syngas yield (89.6%) were calculated and compared to similar CL processes reported in the literature.