Numerical Simulation of Oxidative Conversion of Methane to Synthesis Gas in a Reversed Flow Reactor

A numerical model for the POX steam-oxygen conversion of methane to synthesis gas in a reversed flow nonpremixed filtration combustion reactor with a reversed flow of a steam-methane mixture and a continuous supply of oxygen to the center of the reactor is carried out. The calculations were performed for the oxygen/methane molar ratio of 0.47 and steam/methane molar ratio of 0.5, in the parametric region close to the limit for the feasibility of the scheme. Various modes of initiation and control of flow reversal are considered, and dependences of the combustion temperature and the composition of products on the characteristics of the process are obtained. A comparison of the established cyclic mode of conversion with the predictions of the equilibrium model shows that the kinetic constraints lead to a higher combustion temperature and incomplete conversion of methane. At high temperatures, the conversion proceeds via the initial soot formation during the pyrolysis of methane and the subsequent reaction of soot with steam.