Thermal Modeling and Analysis of a Novel CHP Plant Employing Solid Oxide Fuel Cell and MSW Gasification

The paper deals with the thermal modeling and performance assessment of a municipal solid waste (MSW) gasification fuelled combined heat and power (CHP) plant employing solid oxide fuel cell (SOFC). Both air and steam are considered as gasifying agents for the MSW gasification. The SOFC has been used for the generation of power while the residual heat in the burnt gases is used to produce steam from using a heat recovery steam generator (HRSG) where a certain amount of steam is fed to the gasifier and the rest is utilized for process heating. Thermal and exergetic efficiencies, fuel energy savings ratio (FESR), SOFC output voltage and sustainability index (SI) are the key performance parameters for the plant. The plant offers best performance at an equivalence ratio of 0.25, fuel utilization factor of 0.9 and current density of 2000 A/m2. The maximum values of the thermal and exergetic efficiencies are 64.49% and 57.77%, respectively while maximum FESR is 64% and environmental sustainability index is 2.368, observed at the favorable operating conditions. However, the maximum net power obtainable from the proposed CHP plant is found to be 1821 kW and the maximum heat available for process heating is 360 kW when the current density is raised to as high as 6000 A/m2.