Influence of process variables on gasification of corn silage in supercritical water

Gasification of 5 wt % (DOM) corn silage in supercritical water was investigated in a continuous flow reactor. The influence of pressure, temperature, and residence time on the gas yield was determined. Changing the pressure in the range 250-400 bar did not alter the gas yield. The temperature was varied from 300 to 700 degrees C. At higher temperature, the conversion of biomass in supercritical water was completed. At lower temperature, the biomass is partly converted, and the gas yield is decreased. Residence time variations from 0.6 to 10 min revealed for each investigated temperature that with longer residence time, gas yield increased until a maximum was reached. Gas composition changed with residence time and temperature. At higher temperature, more hydrogen, methane, and ethane were obtained. The gas yield can be modeled in the studied conditions by assuming a zero-order kinetic.