Reforming performances for the double-walled reactor tubes with Na2CO3/MgO composite thermal storage was examined by an intermittent heating The intermittent heating of the reactor tubes is composed of the heat-discharge (or cooling) mode and the subsequent heating mode. The heat-discharging mode simulates a fluctuating Insolation for cloud passages The heating mode simulates a heating of reactor due to concentrated solar radiation by using an electric furnace. The internal tube of the reactor was packed with the 2wt%Ru/Al2O3 catalyst balls while the thermal storage materials were filled in the annular region of the reactor tubes The reactor was heated up to 920 degrees C in the cylindrical electric furnace and the CH4/CO2 mixture was fed into the internal catalyst tube at gas hourly space velocity (GHSV) of 12500 h(-1).
Through the cooling mode and the subsequent heating mode, temperature variations of reactor tubes, catalyst and composite material, H-2/CO ratio variations of effluent gas from the reactor, higher heating value (HHV) power of reformed gas were respectively examined for the double-walled reactor tubes and a single-wall reactor tube without the thermal storage.