Oxy-CFB combustion technology for use in power-generation applications

Abstract

Implementation of circulating fluidized bed (CFB) boilers in the energy sector has witnessed a steady increase owing to their afforded advantages of operational flexibility in terms of compliance with several low-grade fuels and in-situ DeSOx and DeNOx capabilities. In recent years, the rise in global warming and development of intermittent power-generation technologies have stressed the need for development of techniques to afford high-efficiency low-emission (HELE) power-generation, effective carbon capture and storage, and flexible operation of thermal power plants. To meet these demands, the Future Energy Plant Convergence Research Center (FEP CRC) has investigated oxy-combustion technologies for CFB boilers that use low-grade fuels with calorific values <5000 kcal/kg while maintaining high operational efficiency and low pollutant emission. Of key interest in this study is the operation of the proposed system under rapid load variations over a wide operating range, including an oxy-combustion test with high oxygen concentration more than 40% within oxidants. Efforts in this regard are underway through pilot experiments performed using demonstration-scale facilities and multidimensional numerical simulations. Additionally, studies have been performed to identify materials for use in the said high-efficiency boilers and develop techniques for exhaust-system water recovery. In this paper, the current conclusions from the research activities of FEP CRC will be presented.