Experimental study on rice husk combustion in a vortexing fluidized-bed with flue gas recirculation (FGR)

► The combustion behavior of rice husk in a vortexing fluidized-bed combustor (VFBC) is studied. ► Under optimal operation condition, the combustion efficiency of rice husk can reach 99%. ► Effect of FGR can be attributed to the dilute effects, thermal effects, and chemical effects of CO2. ► There is an inverse dependency between the NOx and CO concentrations at the exit of VFBC.