Retrofitting Existing Fluidized Bed Power Plants for Waste-Derived Fuels and CO2 Capture

ended

The goal of this project is to improve the sustainability and rentability of existing coal-fired fluidized bed power plants by means of substitution of coal by waste-derived fuels and integration of CO2 capture technology while maximizing the efficiency, availability, and load flexibility of the power plant. Retrofit concepts of fluidized bed boilers are developed to enable the utilization of waste-derived fuels up to 100 %. The boiler efficiency is maximized by applying oxygen carrier aided combustion. Furthermore, retrofit concepts are developed for more than 90% CO2 capture by means of oxy-fuel and chemical looping combustion, as well as for CO2 utilization or storage. The flexibility of power generation is optimized with respect to ramp-up/down speed, minimum load, and flexible operation of an electrolyzer. The availability of the boiler is maximized by avoiding fouling, corrosion, and erosion of heat exchangers and refractory. Multipollutant emission reduction technologies are used to comply with regulations. The project will demonstrate and assess the developed retrofit concepts in a real environment by tests in a 1 MWth pilot plant and a commercial boiler. The load flexibility and fluidized bed hydrodynamics of the retrofitted power plants will be evaluated by means of dynamic process simulations and CFD simulations, respectively. Finally, the project will provide an environmental, techno- and socio-economic assessment of the developed concepts, in particular for coal regions in transition. These concepts will enable operators of these CFB boilers to use their existing assets beyond the phase-out of coal. The use of waste as fuel is an economic solution due to its low (or even negative) price and permanent availability. Capture, utilization and/or storage of CO2 will support the goal of many utilities to reduce their carbon footprint. Flexible operation of these boilers can be used by power utilities to stabilize the electrical grid.