Optimal Operation Analysis of IGFC System

Abstract

Electrical energy consumption in Thailand increased annually which affects to decrease amount of fossil fuels, an important source of power generation. Thus, biomass, waste from agricultural product, is considered as an alternative source of power generation. Integrated biomass gasification combined cycle is common process for transformation and utilization of biomass to produce electrical energy. However efficiency can be greatly enhanced by using fuel cell technology. Solid oxide fuel cell (SOFC) has received considerable attention in this research because SOFC can operate effectively at the same condition with gasification process. As a result, integration between SOFC and biomass gasification processes can make the high overall plant efficiency. This research studies co-operation system of biomass gasification and power plant technology that called IGFC (integrated gasification fuel cell). This research aims to find the optimal operating conditions in order to make highest power efficiency from rice straw. The operating variables considered include temperature and pressure of gasifier and SOFC, air-to-biomass ratio and steam-to-biomass ratio. Aspen plus is used to perform a simulation in this study. In order to make highest power efficiency, the optimal operating conditions are 3.4 of air-to-biomass ratio, 0.6 of steam-to-biomass ratio, 1000 ˚C of temperature of gasifier, 1000 ˚C of fuel cell temperature, 1 bar of gasifier pressure and 0.5 bar of fuel cell pressure. This condition can generate net power output is 651.35 kW and efficiency is 59.17 %

Keywords: Biomass gasification; Electrical energy; Power generation; Solid oxide fuel cell.