Simulation and Optimization of Hydrogen Fueled Mobile Power Plant Based on Methylcyclohexane-Toluene-Hydrogen Cycle

Increase in CO2 emissions from fossil fuels has threatened the future security of human race. The addition of a renewable and environment friendly energy source to the present energy mix is essentially required. Hydrogen economy is one of the potential solutions for the clean environment and sustainable energy. However, the economical and safe storage of hydrogen is the biggest hurdle in the success of hydrogen on a commercial scale. Hydrogen storage in the form of an organic hydride such as methylcyclohexane, is not only safe, but well developed technology. In the present study, a 2 megawatt hydrogen based mobile power plant is conceptualized and simulated. The concept of the methylcyclohexane-toluene-hydrogen system is employed where the hydrogen required for the gas turbine is obtained from the dehydrogenation of methylcyclohexane. The heat energy required for the highly endothermic dehydrogenation reaction is provided by the turbine exhaust gases. A base-case flowsheet is visualized and the parametric sensitivity of the mobile power plant is studied. The optimization of the operating variables yields the thermal efficiency of the plant as 35.44% and the required methylcyclohexane flowrate equal to 24.96 kmol/h. The modification of the base-case flowsheet, for the optimized conditions, by the regenerative scheme together with the interstage cooling of the two-stage compressor system increased the thermal efficiency of the mobile power plant to 36.79% and decreased the required amount of fresh methylcyclohexane flowrate to 24.04 kmol/h.