Reformer and membrane modules for methane conversion: experimental assessment and perspectives of an innovative architecture.

An innovative concept for steam methane reforming (SMR), based on reformer and membrane modules (RMMs), has been developed and tested to investigate its performance, in terms of feed conversion, on an industrial scale. A major benefit of the proposed RMM configuration is a shift of the chemical equilibrium of SMR reactions, achieved by removing the hydrogen produced at high temperature through the integration of highly selective palladium-based membranes, which enhances the yield of product. In this manner the process can operate at temperatures as low as 600-650 °C, compared to the 850-880 °C range used in conventional plants, and allows for the use of a low-temperature heat source. This Full Paper discusses experimental data on feed conversion at different operating parameters, gathered during 1000 h of testing, and processes these data to optimize the overall architecture, defining the maximum achievable feed conversion. An overall conversion of 59% is achieved with two-step reactions at a reforming temperature of 620 °C. A conversion as high as 90% can be obtained with a three-step architecture at 650 °C by properly extending the design parameters within reasonable limits.