Optimal design of combined cycle power plants with fixed-bed chemical-looping combustion reactors

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 CO2 capture 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. (c) 2018 American Institute of Chemical Engineers AIChE J, 65: e16516 2019