| Abstract
| - The influence of the heat-flux axial profiles on the main variables of an industrial primary steamreformer (i.e., outlet methane conversion, process gas temperature, tube-skin temperature, andequilibrium approach) has been studied. By means of adjustments of the heat flux along thetube length, two different optimization problems have been proposed: (a) maximum methaneconversion for a given maximum allowable tube-skin temperature and (b) minimum tube-skintemperature for a fixed methane conversion, both for constant heat duty. The defined optimizationproblems have been solved using a one-dimensional heterogeneous model. This mathematicalformulation accounts for the strong mass-transfer resistances by an appropriate solution of thematerial balances within the catalyst. An equivalent annular model has been used to representthe complex geometry of the catalyst particle. The simulation and optimization results indicatethat the heat flux strongly influences the reactor performance. Indeed, adequate selections ofthe heat-flux distribution along the reactor length would increase the production rate and/orextend the tube lifetime significantly.
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