A modified membrane SMR reactor to produce large-scale syngas: modeling and multi objective optimization

In this research, a conventional steam methane reforming (SMR) reactor is modified to enhance CH4 conversion and decreasing pressure drop considering membrane and distributed feeding policy. In the proposed structure, some feeding points are considered along the membrane reactor and steam is injected to the reactor through feeding nodes. It is demonstrated that a suitable distributed feeding policy improves performance of SMR process. The modified membrane reactor is modeled based on the mass and energy conservation laws. In the optimization section, the optimal rate of steam injection at considered nodes are calculated to maximize CH4 conversion and minimize pressure drop based on the multi-objective optimization considering coke formation limitations. The elitist non-dominated sorting genetic algorithm is employed to obtain the Pareto frontier in two objective spaces. The single optimal solution is selected from Pareto frontier by the decision-making methods including Shannon Entropy, LINMAP and TOPSIS. The results show that as well as lower pressure drop and higher methane conversion, hydrogen production is improved about 18.09% in the optimized configuration based TOPSIS methods.