Solid fuels reduced oxygen carrier

The authors also propose a CFB reactor set-up for CLC operation with solid fuels (see Figure 4). A high velocity riser is suggested for the oxidizer, and a down-flow moving bed or bubbling fluidized bed for the reducer in which the solid fuel is fed. A low-velocity bubbling bed or turbulent fluidized bed thus acts as deep reduction reactor and separator for oxygen carriers from fly ash and unbumt carbon. In this... 

The oxidized solid oxygen carrier is subsequently circulated into reactor 2, where it is reduced by the fuel (which is consequently oxidized) either to metal or to a reduced oxide form. 

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