Comparison of Exergy Losses for Reformers Involved in Hydrogen and Synthesis Gas Production

A user-coded, customized methodology for exergy balance and analysis of chemical and thermal processes is developed with the Aspen HYSYS process simulator, to assess and explain exergy loss in steam methane reforming. Exergy analysis is presented for four configurations of primary and secondary reformers to produce synthesis gas: (1) an autothermal reformer (ATR) alone, (2) a top-fired reformer (TFR) alone, (3) ATR-TFR configured in parallel, and (4) ATR-TFR configured in series. The same states and feed conditions, i.e., mass flow rate, temperature, pressure, and feed gas composition, are applied to the four reformer configurations considered, with the single ATR showing the lowest exergy loss of about 0.43 W kg(-1) of dry productivity.