Investigation on performance optimization of a novel microreactor with multiple-pulsation combustion for methanol steam reforming to hydrogen production for proton exchange membrane fuel cell

Amid the global push for sustainable development, the advancement of green energy has become essential. Proton exchange membrane fuel cells (PEMFCs) have garnered significant attention due to their high efficiency and low environmental impact. Specifically, PEMFCs operating on methanol achieve an efficiency of 20-30 %, whereas those using hydrogen can reach efficiencies of 50-60 %. In order to address the challenges of hydrogen storage and transportation, this study designs a ready-to-use micro-combustion-methanol steam reforming (MCMSR) reactor and further proposes a multiple-pulsation reactor based on this design. The inlet structure of the micro-combustor is optimized by introducing graded steps, which enhance the burner's heat transfer performance and improve wall temperature uniformity by approximately 21.6 %. For reactor optimization, increasing the inlet temperature of the reforming zone reduces the temperature gradient in the reforming region, resulting in a 36.4 % reduction in methanol fuel consumption compared to the primitive reactor. Additionally, under conditions where the input flow rate of the H2O/CH3OH mixture is 10-6 kg/s and the molar fraction ratio of H2O/ CH3OH is 0.9, the reactor achieves a hydrogen production mass flow rate of 6.894 x 10-8.