A comparison of two different flow types on performance of a thermally coupled recuperative reactor containing naphtha reforming process and hydrogenation of nitrobenzene

Refineries have been looking for proper ways of improving reformer performance by enhancing the octane number of the product via increasing the aromatics’ compounds. To reach this goal, the endothermic catalytic naphtha reforming is coupled with the exothermic hydrogenation of nitrobenzene to aniline in a multifunctional heat exchanger reactor through the process intensification concept. Considering the higher thermal efficiency as well as the smaller size of the coupled reactor, utilizing this reactor is given priority. In this novel configuration, the first and the second reactor of the conventional naphtha reforming process are exchanged with the coupled reactors contain the endothermic naphtha reforming in the shell side and the hydrogenation reaction in the tube side. Both co-current and counter-current modes of flow are examined during the operation considering various studies in literature which show the superiority of co-current flow compared with the counter-current flow. The result of current study is compared with the corresponding results for conventional tubular reactor (CTR). The results show higher aromatic production as much as 18.73% and 16.48% in the co-current and counter-current mode, respectively. Hydrogen molar flow rate increases about 5 kmol/h by using counter-current flow regime, compared with the CTR.