Modeling of an integrated two-stage biomass gasifier and solid oxide fuel cell system

A new conceptual integrated two-stage biomass gasifier and solid oxide fuel cell (SOFC) system is proposed and a multi-physics model for predicting the performance of this system is developed. A method coupling the modeling equations of a quasi 2-D model for SOFC, a 1-D model for pyrolysis reactor, and 0-D model for the remaining components is applied. Several parametric studies are conducted using the model developed. With the main objective of operating this system being maximizing the net power output, the results for the parametric studies conducted show that the number of SOFC stacks, the mass ratio of air to steam entering the gasifier, and the temperature of the pre-heated air entering the gasifier should be taken as high as possible; whereas the moisture ratio of the wet biomass should be minimized; and there is an optimum point for the rotational speed of the pyrolysis reactor. For the considered input data and the range of parameters studied, the maximum net power output of the system is found to be 93 kW. At this condition, the useful heat output, the electrical efficiency of the system, and the fuel utilization efficiency are calculated as 71 kW, 25%, and 44%, respectively.

► A new integrated two-stage biomass gasifier and SOFC system is proposed. ► A multi-physics model for predicting the performance of this system is developed. ► For the given data, the maximum net power output that can be achieved is 93 kW. ► At this condition, electrical efficiency of the integrated system is found as 25%.