Patent ID: 8287610

Claim:
A method for at least partially reacting biomass particles to form reaction products comprising hydrogen and carbon monoxide, the method comprising the steps of: a) providing a solar-thermal reactor comprising an outer protection shell and one or more inner reaction shells having an inlet and an outlet, the outer protection shell having an opening to the atmosphere for transmission of solar energy; b) flowing a gas stream from the inlet to the outlet of the reaction shell, the gas stream comprising entrained biomass particles at the inlet of the one or more inner reaction shells, the volume average equivalent spherical particle diameter of the biomass particles being between 10 micron and 10 mm; and c) rapidly heating the biomass particles in the reactor through solar thermal heating to a temperature of at least 950Â° C. at least in part by exposing the reactor to a source of concentrated sunlight, wherein the biomass particles react to form products comprising hydrogen and carbon monoxide, wherein the temperature of at least 950Â° C. is used to at least bypass formation of tar, where the ash content of the biomass particles exiting the solar-thermal reactor is less than 15% and conversion of the non-ash components of the biomass particles is greater than 50%.