Temperature, steam flow rate and coal/biomass ratio in the feedstock are the key factors that affect the performances of co–gasification processes. A three-dimensional computational fluid dynamics (CFD) method matched with homogenous chemical reactions were used to visualize hydrogen concentration gradient in a fixed-bed reactor. The Eulerian-Eulerian CFD method was promoted to investigate the effect of various ranges of temperatures (700 to 950ºC), water flow rates (0.5×10-8 to 3.3×10-8 m3/s) and coal/biomass ratio (0 to 100%) on the gasification efficiency. All numerical operations were under time-dependent conditions by depicting concentration contours for H2 production. Using the CFD technique, the desirable circumstances for maximum H2 production were specified as temperature of 850°C, water flow rate of 1.9 × 10−3 m3/s and coal/biomass ratio of around 50%. A comparison between the simulation results and experimental gasification data was conducted to approve the CFD results, and there was an acceptable agreement among them.
