A study on principal component for chemically recuperated gas turbine with natural gas steam reforming (1st report, system characteristics of CRGT and design of reformer)

Small-and-medium-sized gas turbines widely spread for distributed power and combined heat and power. However, most of their generating efficiencies are less than 35% because of simple cycle. Chemically recuperated gas turbine (CRGT) is an advanced cycle, which recovers exhaust heat by endothermic reaction converting fuel into hydrogen-rich gas, and several papers report that CRGT would be effective to improve generating efficiency of the simple cycle GT in feasibility study. Also, the CRGT using methanol steam reforming has been demonstrated, but the components and system operation has not been assessed technically in case of natural gas. In order to realize the CRGT with natural gas steam reforming, we applied the CR system to a commercial 4 MW simple cycle GT and surveyed effects of several parameters on the static mass and heat balance. On the basis of typical mass and heat balance, we also designed a heat recovery reformer by numerical analysis considering mass and heat transfer and chemical reaction.