Production of Syngas
Solar radiation is collected and concentrated and heats particles (or bed material) in the particle receiver to approximately 950°C. These particles are stored in the hot particle storage system to be used as required by the bubbling fluidized bed gasifier (BFBG). In the other process, the solid fuel is fed to the BFBG, where it reacts with steam (the fluidizing agent for the BFBG) at 850°C to produce syngas, a gaseous mixture comprising predominantly H2 and CO. The heat required by the endothermic gasification reactions is provided by hot bed material transferred from the hot particle storage system (under solar mode) and the cooled particles are transported back to the cold particle storage system via the fast fluidized bed combustor (FFBC). When stored hot particles are not available, the cooled-bed material from the BFBG is heated up and transported back to BFBG by high velocity flue gas through a cyclone. The residual char within the bed material from BFBG is burned with air (the fluidizing agent for the FFBC) in the FFBC. Additional fuel is required in the FFBC when the residual char is insufficient to provide the necessary heat for the gasification process and to overcome heat losses. Fine particles and contaminants in the syngas are removed in the gas cleaning system before it is synthesized in the Fischer-Tropsch (FT) reactor at 260°C and 26bar. The FT liquids are refined into diesel and gasoline.