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Process intensification options are explored for near‐carbon‐neutral, natural‐gas‐fueled combined cycle (CC) power plants, wherein the conventional combustor is replaced by a series of chemical‐looping combustion (CLC) reactors. Dynamic modeling and optimization are deployed to design CLC‐CC power plants with optimal configuration and performance. The overall plant efficiency is improved by optimizing the CLC reactor design and operation, and modifying the CC plant configuration and design. The optimal CLC‐CC power plant has a time‐averaged efficiency of 52.52% and CO₂capture efficiency of 96%. The main factor that limits CLC‐CC power plant efficiency is the reactor temperature, which is constrained by the oxygen carrier material. CLC exhaust gas temperature during heat removal and gas compressor to gas turbine pressure ratio are the most important operating variables and if properly tuned, CLC‐CC power plants can reach high thermodynamic efficiencies. © 2018 American Institute of Chemical EngineersAIChE J, 65: e16516 2019

Chemical‐looping combustion (CLC) is a promising and efficient method for power generation with in situ CO₂capture. In this work, we focus on high‐pressure fixed‐bed CLC reactors integrated with combined cycle (CC) power plants. Specifically, the dynamic nature of fixed‐bed chemical‐looping reactors and the many kinetically controlled reactions necessitate the use of dynamic modeling to evaluate power plant performance, efficiency, stability, and feasibility under transient operation. We present a dynamic model for an integrated CLC–CC power plant and transient analyses of the integrated plant performance. A network of dynamically operated fixed‐bed reactors fed with natural gas comprises the CLC plant component. A dynamic model is developed and tuned to match the performance of a commercial combined cycle power plant. The transient variations of the integrated plant in terms of power, temperature, and pressure profiles are presented. The simulation results show that despite the inherent batch‐type operation of the CLC reactor, the operation of the combined cycle is relatively unaffected, and there are small oscillations of approximately 2 % around the desired steady‐state conditions.