Development of a Dynamic Cathode Ejector Model for Solid Oxide Fuel Cell-Gas Turbine Hybrid Systems

James D Maclay,Jacob Brouwer,G Scott Samuelsen

doi:10.1115/1.4003774

Abstract

Solid oxide fuel cell-gas turbine (SOFC-GT) hybrid systems are attractive for future power generation with ultra-low criteria pollutant and greenhouse gas emissions. One of the challenges for SOFC-GT systems is to sufficiently pre-heat incoming air before it enters the fuel cell cathode. An ejector for cathode exhaust recirculation has the benefits of reliability, low maintenance, and cost compared to either recuperators or cathode recirculation blowers, which may be also be used for air pre-heating. In this study, a dynamic Simulink model of an ejector for cathode exhaust recirculation to pre-heat incoming fuel cell air has been developed. The ejector is to be utilized within a 100 MW SOFC-GT dynamic model operating on coal syngas. A thorough theoretical development is presented. Results for the ejector were found to be in good agreement with those reported in literature.

Highlights

The need for advanced coal based power generation has led to the concept of an integrated gasification fuel cell system (IGFC)
The main power block in this system is comprised of a solid oxide fuel cell (SOFC) integrated with a gas turbine (GT) operating on coal syngas
The main benefits of IGFC systems are that they allow operation on an abundant and cheap fuel and by using syngas in place of solid coal many of the toxic emissions associated with coal based power generation are removed

Summary

Scott Samuelsen

Solid oxide fuel cell-gas turbine (SOFC-GT) hybrid systems are attractive for future power generation with ultra-low criteria pollutant and greenhouse gas emissions. One of the challenges for SOFC-GT systems is to sufficiently pre-heat incoming air before it enters the fuel cell cathode. An ejector for cathode exhaust recirculation has the benefits of reliability, low maintenance, and cost compared to either recuperators or cathode recirculation blowers, which may be be used for air pre-heating. A dynamic Simulink model of an ejector for cathode exhaust recirculation to pre-heat incoming fuel cell air has been developed. The ejector is to be utilized within a 100 MW SOFC-GT dynamic model operating on coal syngas. Results for the ejector were found to be in good agreement with those reported in literature.

Introduction

Model Development

Results and Discussion

Conclusions