Abstract
Aiming at hydrogen production system using heat produced by a nuclear reactor at about 300 degrees centigrade, we are developing a dimethyl ether (DME) steam reformer, hydrogen purification systems as well as catalysts for DME reforming. The use of heats from a nuclear reactor suppresses the CO_2 concentration change in atmosphere. In our developments, a catalyst, which is mixed oxides, produced hydrogen at a rate of about 2000 L/h per catalyst volume (L) at about 300 degrees centigrade. Then, the DME steam reformer achieved a hydrogen production rate of about, at least, 1.4 Nm3/h at about 300 degrees centigrade, by absorbing heat from the supplied steam. The hydrogen production system by the DME steam reforming above is to be demonstrated using a thermal power plant. DME steam reforming by using waste heat and utilization of the produced hydrogen in a combined cycle power plant can reduce fuel, for instance, by about 17% compared to the case of the direct DME combustion. If necessary, byproduced CO2 may be injected into coal seam, increasing CH_4 production by substitution of CO_2 for CH_4 on coal, where CO_2 adsorption is expected to be stronger than the CH_4 adsorption.