Systems and methods for biomass gasifier reactor and receiver configuration

A solar-driven chemical plant, comprising:

• a solar thermal receiver aligned to absorb concentrated solar energy from one or more solar energy concentrating fields including 1) an array of heliostats, 2) solar concentrating dishes, and 3) any combination of the two, where the solar thermal receiver has cavity walls;
• a solar driven chemical reactor that has multiple reactor tubes in a downdraft configuration located inside the solar thermal receiver, where in the multiple reactor tubes particles of biomass are gasified in the presence of a carrier gas in an endothermic gasification reactions to produce hydrogen and carbon monoxide products at an exit temperature from the tubes exceeding 1000 degrees C.;
• and
• an aperture 1) open to an atmosphere of the Earth or 2) covered with a transparent window, to pass the concentrated solar energy into the solar thermal receiver to impinge on the multiple reactor tubes and cavity walls of the receiver, wherein the reactor tubes serve the dual functions of 1) segregating the biomass gasification reaction environment from the atmosphere of the solar thermal receiver and 2) transferring solar energy by absorption and re-radiation, convection, and conduction to the reacting particles to drive the endothermic gasification reactions of the particles of biomass flowing through the reactor tubes, and wherein high heat transfer rates of the materials making up the cavity walls and the reactor tubes allow the particles biomass to achieve a high enough temperature necessary for substantial tar destruction to less than 200 mg/m̂3 and preferably less than 50 mg/m̂3 and gasification of greater than 90 percent of the carbon content of the particles into reaction products including hydrogen and carbon monoxide gas in a very short residence time between a range of 0.01 and 5 seconds.