Experimental investigation of the effect of microwave power on the chemical looping gasification of aquatic plant water hyacinth

In this study, the gaseous products and tar characteristics of chemical looping gasification of aquatic plant water hyacinth were investigated under different microwave powers. It was found that the total gas production, the proportion of (CO and H2), and the cold gas efficiency increased from 0.54 Nm3/kg, 49.73 %, 66.52 % to 0.68 Nm3/kg, 67.76 %, and 78.66 %, respectively, as the microwave power increased from 400 to 1000 W. However, the yield of tar was reduced with the increasing microwave power. With the increase of microwave power, the specific surface area is increased due to the formation of pores on the surface of the oxygen carrier. Besides, the addition of microwave power promotes the release of lattice oxygen, which brings a higher reduction degree of Fe species in the oxygen carrier. Furthermore, the carbon attached to the surface of the oxygen carrier changes from fragmented carbon deposition to layered carbon deposition, which effectively avoids the rapid deactivation of the oxygen carrier. Therefore, the gasification reaction rate can be increased and better gas quality be obtained under higher microwave power conditions for chemical looping gasification of water hyacinth.