Fusion Science and Technology / Volume 52 / Number 3 / October 2007 / Pages 756-760
Technical Paper / The Technology of Fusion Energy - Nonelectric Applications
The paper proposes a conceptual design of hydrogen production system with unused biomass wastes and steam generated from high temperature nuclear power systems including fusion reactor. A reaction of interest is expressed as a formula, (C6H10O5)n + nH2O => 6nH2 + 6nCO, which is accompanied by a large quantity of endothermic reaction. Basic experiments have been made of thermal decomposition of cellulose, specimen as biomass resource, with the aid of high temperature steam of 1000 deg C heated by an infrared image furnace. The endothermic quantity was evaluated from a numerical model in which measured temperatures are employed. The numerical results for endothermic quantity agreed well with the theoretical value of 816 kJ/mol. To discuss the technical feasibility of the present process, the conceptual design of a hydrogen production reactor system of heat exchanger type was made with the numerical results and heat transfer correlations for helium and steam flow. The present biomass based process, producing both electricity and more hydrogen than other processes such as water or steam electrolysis using an equivalent quantity of heat source, is characterized as an efficient hydrogen production method using nuclear thermal energy, which simultaneously contributes to reduce biomass wastes.