Semi-batch Chemical-looping Reactors Integrated with Combined Cycle Power Plants Operating at Transient Electricity Demand

Chemical-looping combustion (CLC) is a promising process for power generation with low energy penalty and in-situ CO2 capture. In this work, we focus on the integration of high-pressure, fixed-bed CLC reactors with combined cycle (CC) power plants. We deal with the discontinuous operation of fixedbed reactors and the dynamic simulation of CLC-CC power plants, which is nontrivial. Modern power plants have to operate in response to daily and seasonal fluctuations in power demand, and balance the electric grid input from renewable sources to maintain grid reliability. Thus, dynamic simulation and optimization of novel power plant configurations with integrated CO2 capture functions, in response to changing fuel loads are critical in addressing the dynamicity of the electricity market. Given the complexity of the regulatory controllers implemented in a power plant, a supervisory control system is proposed to dynamically optimize the power plant efficiency. The optimal plant efficiency is estimated at 48.9% by optimizing the operation strategy of the CLC reactors. The dynamic analysis shows that the discontinuous operation of batch-type reactors only slightly affects the process efficiency and stability. Dynamic optimization is performed for the fossil-fueled power plant, demonstrating the potential of improvement in the time-averaged real-time efficiency by 1.53% points, with corresponding savings in coal consumption.